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Sample records for brain motor control

  1. Efficient foot motor control by Neymar’s brain

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    Eiichi eNaito

    2014-08-01

    Full Text Available How very long-term (over many years motor skill training shapes internal motor representation remains poorly understood. We provide valuable evidence that the football brain of Neymar da Silva Santos Júnior (the Brasilian footballer recruits very limited neural resources in the motor-cortical foot regions during foot movements. We scanned his brain activity with a 3-tesla functional magnetic resonance imaging (fMRI while he rotated his right ankle at 1Hz. We also scanned brain activity when three other age-controlled professional footballers, two top-athlete swimmers and one amateur footballer performed the identical task. A comparison was made between Neymar’s brain activity with that obtained from the others. We found activations in the left medial-wall foot motor regions during the foot movements consistently across all participants. However, the size and intensity of medial-wall activity was smaller in the four professional footballers than in the three other participants, despite no difference in amount of foot movement. Surprisingly, the reduced recruitment of medial-wall foot motor regions became apparent in Neymar. His medial-wall activity was smallest among all participants with absolutely no difference in amount of foot movement. Neymar may efficiently control given foot movements probably by largely conserving motor-cortical neural resources. We discuss this possibility in terms of over-years motor skill training effect, use-dependent plasticity, and efficient motor control.

  2. Motor control of handwriting in the developing brain: A review.

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    Palmis, Sarah; Danna, Jeremy; Velay, Jean-Luc; Longcamp, Marieke

    This review focuses on the acquisition of writing motor aspects in adults, and in 5-to 12-year-old children without learning disabilities. We first describe the behavioural aspects of adult writing and dominant models based on the notion of motor programs. We show that handwriting acquisition is characterized by the transition from reactive movements programmed stroke-by-stroke in younger children, to an automatic control of the whole trajectory when the motor programs are memorized at about 10 years old. Then, we describe the neural correlates of adult writing, and the changes that could occur with learning during childhood. The acquisition of a new skill is characterized by the involvement of a network more restricted in space and where neural specificity is increased in key regions. The cerebellum and the left dorsal premotor cortex are of fundamental importance in motor learning, and could be at the core of the acquisition of handwriting.

  3. Sensorless speed control of switched reluctance motor using brain emotional learning based intelligent controller

    International Nuclear Information System (INIS)

    Dehkordi, Behzad Mirzaeian; Parsapoor, Amir; Moallem, Mehdi; Lucas, Caro

    2011-01-01

    In this paper, a brain emotional learning based intelligent controller (BELBIC) is developed to control the switched reluctance motor (SRM) speed. Like other intelligent controllers, BELBIC is model free and is suitable to control nonlinear systems. Motor parameter changes, operating point changes, measurement noise, open circuit fault in one phase and asymmetric phases in SRM are also simulated to show the robustness and superior performance of BELBIC. To compare the BELBIC performance with other intelligent controllers, Fuzzy Logic Controller (FLC) is developed. System responses with BELBIC and FLC are compared. Furthermore, by eliminating the position sensor, a method is introduced to estimate the rotor position. This method is based on Adaptive Neuro Fuzzy Inference System (ANFIS). The estimator inputs are four phase flux linkages. Suggested rotor position estimator is simulated in different conditions. Simulation results confirm the accurate rotor position estimation in different loads and speeds.

  4. Sensorless speed control of switched reluctance motor using brain emotional learning based intelligent controller

    Energy Technology Data Exchange (ETDEWEB)

    Dehkordi, Behzad Mirzaeian, E-mail: mirzaeian@eng.ui.ac.i [Department of Electrical Engineering, Faculty of Engineering, University of Isfahan, Hezar-Jerib St., Postal code 8174673441, Isfahan (Iran, Islamic Republic of); Parsapoor, Amir, E-mail: amirparsapoor@yahoo.co [Department of Electrical Engineering, Faculty of Engineering, University of Isfahan, Hezar-Jerib St., Postal code 8174673441, Isfahan (Iran, Islamic Republic of); Moallem, Mehdi, E-mail: moallem@cc.iut.ac.i [Department of Electrical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of); Lucas, Caro, E-mail: lucas@ut.ac.i [Centre of Excellence for Control and Intelligent Processing, Electrical and Computer Engineering Faculty, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)

    2011-01-15

    In this paper, a brain emotional learning based intelligent controller (BELBIC) is developed to control the switched reluctance motor (SRM) speed. Like other intelligent controllers, BELBIC is model free and is suitable to control nonlinear systems. Motor parameter changes, operating point changes, measurement noise, open circuit fault in one phase and asymmetric phases in SRM are also simulated to show the robustness and superior performance of BELBIC. To compare the BELBIC performance with other intelligent controllers, Fuzzy Logic Controller (FLC) is developed. System responses with BELBIC and FLC are compared. Furthermore, by eliminating the position sensor, a method is introduced to estimate the rotor position. This method is based on Adaptive Neuro Fuzzy Inference System (ANFIS). The estimator inputs are four phase flux linkages. Suggested rotor position estimator is simulated in different conditions. Simulation results confirm the accurate rotor position estimation in different loads and speeds.

  5. Strong Functional Connectivity among Homotopic Brain Areas Is Vital for Motor Control in Unilateral Limb Movement

    Directory of Open Access Journals (Sweden)

    Pengxu Wei

    2017-07-01

    Full Text Available The mechanism underlying brain region organization for motor control in humans remains poorly understood. In this functional magnetic resonance imaging (fMRI study, right-handed volunteers were tasked to maintain unilateral foot movements on the right and left sides as consistently as possible. We aimed to identify the similarities and differences between brain motor networks of the two conditions. We recruited 18 right-handed healthy volunteers aged 25 ± 2.3 years and used a whole-body 3T system for magnetic resonance (MR scanning. Image analysis was performed using SPM8, Conn toolbox and Brain Connectivity Toolbox. We determined a craniocaudally distributed, mirror-symmetrical modular structure. The functional connectivity between homotopic brain areas was generally stronger than the intrahemispheric connections, and such strong connectivity led to the abovementioned modular structure. Our findings indicated that the interhemispheric functional interaction between homotopic brain areas is more intensive than the interaction along the conventional top–down and bottom–up pathways within the brain during unilateral limb movement. The detected strong interhemispheric horizontal functional interaction is an important aspect of motor control but often neglected or underestimated. The strong interhemispheric connectivity may explain the physiological phenomena and effects of promising therapeutic approaches. Further accurate and effective therapeutic methods may be developed on the basis of our findings.

  6. Strong Functional Connectivity among Homotopic Brain Areas Is Vital for Motor Control in Unilateral Limb Movement.

    Science.gov (United States)

    Wei, Pengxu; Zhang, Zuting; Lv, Zeping; Jing, Bin

    2017-01-01

    The mechanism underlying brain region organization for motor control in humans remains poorly understood. In this functional magnetic resonance imaging (fMRI) study, right-handed volunteers were tasked to maintain unilateral foot movements on the right and left sides as consistently as possible. We aimed to identify the similarities and differences between brain motor networks of the two conditions. We recruited 18 right-handed healthy volunteers aged 25 ± 2.3 years and used a whole-body 3T system for magnetic resonance (MR) scanning. Image analysis was performed using SPM8, Conn toolbox and Brain Connectivity Toolbox. We determined a craniocaudally distributed, mirror-symmetrical modular structure. The functional connectivity between homotopic brain areas was generally stronger than the intrahemispheric connections, and such strong connectivity led to the abovementioned modular structure. Our findings indicated that the interhemispheric functional interaction between homotopic brain areas is more intensive than the interaction along the conventional top-down and bottom-up pathways within the brain during unilateral limb movement. The detected strong interhemispheric horizontal functional interaction is an important aspect of motor control but often neglected or underestimated. The strong interhemispheric connectivity may explain the physiological phenomena and effects of promising therapeutic approaches. Further accurate and effective therapeutic methods may be developed on the basis of our findings.

  7. A binary motor imagery tasks based brain-computer interface for two-dimensional movement control

    Science.gov (United States)

    Xia, Bin; Cao, Lei; Maysam, Oladazimi; Li, Jie; Xie, Hong; Su, Caixia; Birbaumer, Niels

    2017-12-01

    Objective. Two-dimensional movement control is a popular issue in brain-computer interface (BCI) research and has many applications in the real world. In this paper, we introduce a combined control strategy to a binary class-based BCI system that allows the user to move a cursor in a two-dimensional (2D) plane. Users focus on a single moving vector to control 2D movement instead of controlling vertical and horizontal movement separately. Approach. Five participants took part in a fixed-target experiment and random-target experiment to verify the effectiveness of the combination control strategy under the fixed and random routine conditions. Both experiments were performed in a virtual 2D dimensional environment and visual feedback was provided on the screen. Main results. The five participants achieved an average hit rate of 98.9% and 99.4% for the fixed-target experiment and the random-target experiment, respectively. Significance. The results demonstrate that participants could move the cursor in the 2D plane effectively. The proposed control strategy is based only on a basic two-motor imagery BCI, which enables more people to use it in real-life applications.

  8. Automatic motor task selection via a bandit algorithm for a brain-controlled button

    Science.gov (United States)

    Fruitet, Joan; Carpentier, Alexandra; Munos, Rémi; Clerc, Maureen

    2013-02-01

    Objective. Brain-computer interfaces (BCIs) based on sensorimotor rhythms use a variety of motor tasks, such as imagining moving the right or left hand, the feet or the tongue. Finding the tasks that yield best performance, specifically to each user, is a time-consuming preliminary phase to a BCI experiment. This study presents a new adaptive procedure to automatically select (online) the most promising motor task for an asynchronous brain-controlled button. Approach. We develop for this purpose an adaptive algorithm UCB-classif based on the stochastic bandit theory and design an EEG experiment to test our method. We compare (offline) the adaptive algorithm to a naïve selection strategy which uses uniformly distributed samples from each task. We also run the adaptive algorithm online to fully validate the approach. Main results. By not wasting time on inefficient tasks, and focusing on the most promising ones, this algorithm results in a faster task selection and a more efficient use of the BCI training session. More precisely, the offline analysis reveals that the use of this algorithm can reduce the time needed to select the most appropriate task by almost half without loss in precision, or alternatively, allow us to investigate twice the number of tasks within a similar time span. Online tests confirm that the method leads to an optimal task selection. Significance. This study is the first one to optimize the task selection phase by an adaptive procedure. By increasing the number of tasks that can be tested in a given time span, the proposed method could contribute to reducing ‘BCI illiteracy’.

  9. Transferring brain-computer interfaces beyond the laboratory: successful application control for motor-disabled users.

    Science.gov (United States)

    Leeb, Robert; Perdikis, Serafeim; Tonin, Luca; Biasiucci, Andrea; Tavella, Michele; Creatura, Marco; Molina, Alberto; Al-Khodairy, Abdul; Carlson, Tom; Millán, José D R

    2013-10-01

    Brain-computer interfaces (BCIs) are no longer only used by healthy participants under controlled conditions in laboratory environments, but also by patients and end-users, controlling applications in their homes or clinics, without the BCI experts around. But are the technology and the field mature enough for this? Especially the successful operation of applications - like text entry systems or assistive mobility devices such as tele-presence robots - requires a good level of BCI control. How much training is needed to achieve such a level? Is it possible to train naïve end-users in 10 days to successfully control such applications? In this work, we report our experiences of training 24 motor-disabled participants at rehabilitation clinics or at the end-users' homes, without BCI experts present. We also share the lessons that we have learned through transferring BCI technologies from the lab to the user's home or clinics. The most important outcome is that 50% of the participants achieved good BCI performance and could successfully control the applications (tele-presence robot and text-entry system). In the case of the tele-presence robot the participants achieved an average performance ratio of 0.87 (max. 0.97) and for the text entry application a mean of 0.93 (max. 1.0). The lessons learned and the gathered user feedback range from pure BCI problems (technical and handling), to common communication issues among the different people involved, and issues encountered while controlling the applications. The points raised in this paper are very widely applicable and we anticipate that they might be faced similarly by other groups, if they move on to bringing the BCI technology to the end-user, to home environments and towards application prototype control. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. [Arm Motor Function Recovery during Rehabilitation with the Use of Hand Exoskeleton Controlled by Brain-Computer Interface: a Patient with Severe Brain Damage].

    Science.gov (United States)

    Biryukova, E V; Pavlova, O G; Kurganskaya, M E; Bobrov, P D; Turbina, L G; Frolov, A A; Davydov, V I; Sil'tchenko, A V; Mokienko, O A

    2016-01-01

    We studied the dynamics of motor function recovery in a patient with severe brain damage in the course of neurorehabilitation using hand exoskeleton controlled by brain-computer interface. For estimating the motor function of paretic arm, we used the biomechanical analysis of movements registered during the course of rehabilitation. After 15 weekly sessions of hand exoskeleton control, the following results were obtained: a) the velocity profile of goal-directed movements of paretic hand became bell-shaped, b) the patient began to extend and abduct the hand which was flexed and adducted in the beginning of rehabilitation, and c) the patient began to supinate the forearm which was pronated in the beginning of rehabilitation. The first result is an evidence of the general improvement of the quality of motor control, while the second and third results prove that the spasticity of paretic arm has decreased.

  11. Principles of Motor Recovery in Post-Stroke Patients using Hand Exoskeleton Controlled by the Brain-Computer Interface Based on Motor Imagery

    Czech Academy of Sciences Publication Activity Database

    Frolov, A. A.; Húsek, Dušan; Biryukova, E. V.; Bobrov, P.; Mokienko, O.; Alexandrov, A.V.

    2017-01-01

    Roč. 27, č. 1 (2017), s. 107-137 ISSN 1210-0552 Grant - others:Russian Ministry of Education and Science(RU) RFMEFI60715X0128 Institutional support: RVO:67985807 Keywords : brain computer interface * motor imagery * post-stroke and post-traumatic patients * arm and hand exoskeleton * proportional derivative controller * motor synergy * clinical application Subject RIV: IN - Informatics, Computer Science OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 0.394, year: 2016

  12. Fine motor control

    Science.gov (United States)

    ... gross (large, general) motor control. An example of gross motor control is waving an arm in greeting. Problems ... out the child's developmental age. Children develop fine motor skills over time, by practicing and being taught. To ...

  13. Brain-computer interface controlled gaming: evaluation of usability by severely motor restricted end-users.

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    Holz, Elisa Mira; Höhne, Johannes; Staiger-Sälzer, Pit; Tangermann, Michael; Kübler, Andrea

    2013-10-01

    Connect-Four, a new sensorimotor rhythm (SMR) based brain-computer interface (BCI) gaming application, was evaluated by four severely motor restricted end-users; two were in the locked-in state and had unreliable eye-movement. Following the user-centred approach, usability of the BCI prototype was evaluated in terms of effectiveness (accuracy), efficiency (information transfer rate (ITR) and subjective workload) and users' satisfaction. Online performance varied strongly across users and sessions (median accuracy (%) of end-users: A=.65; B=.60; C=.47; D=.77). Our results thus yielded low to medium effectiveness in three end-users and high effectiveness in one end-user. Consequently, ITR was low (0.05-1.44bits/min). Only two end-users were able to play the game in free-mode. Total workload was moderate but varied strongly across sessions. Main sources of workload were mental and temporal demand. Furthermore, frustration contributed to the subjective workload of two end-users. Nevertheless, most end-users accepted the BCI application well and rated satisfaction medium to high. Sources for dissatisfaction were (1) electrode gel and cap, (2) low effectiveness, (3) time-consuming adjustment and (4) not easy-to-use BCI equipment. All four end-users indicated ease of use as being one of the most important aspect of BCI. Effectiveness and efficiency are lower as compared to applications using the event-related potential as input channel. Nevertheless, the SMR-BCI application was satisfactorily accepted by the end-users and two of four could imagine using the BCI application in their daily life. Thus, despite moderate effectiveness and efficiency BCIs might be an option when controlling an application for entertainment. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Brain-Computer Interface application: auditory serial interface to control a two-class motor-imagery-based wheelchair.

    Science.gov (United States)

    Ron-Angevin, Ricardo; Velasco-Álvarez, Francisco; Fernández-Rodríguez, Álvaro; Díaz-Estrella, Antonio; Blanca-Mena, María José; Vizcaíno-Martín, Francisco Javier

    2017-05-30

    Certain diseases affect brain areas that control the movements of the patients' body, thereby limiting their autonomy and communication capacity. Research in the field of Brain-Computer Interfaces aims to provide patients with an alternative communication channel not based on muscular activity, but on the processing of brain signals. Through these systems, subjects can control external devices such as spellers to communicate, robotic prostheses to restore limb movements, or domotic systems. The present work focus on the non-muscular control of a robotic wheelchair. A proposal to control a wheelchair through a Brain-Computer Interface based on the discrimination of only two mental tasks is presented in this study. The wheelchair displacement is performed with discrete movements. The control signals used are sensorimotor rhythms modulated through a right-hand motor imagery task or mental idle state. The peculiarity of the control system is that it is based on a serial auditory interface that provides the user with four navigation commands. The use of two mental tasks to select commands may facilitate control and reduce error rates compared to other endogenous control systems for wheelchairs. Seventeen subjects initially participated in the study; nine of them completed the three sessions of the proposed protocol. After the first calibration session, seven subjects were discarded due to a low control of their electroencephalographic signals; nine out of ten subjects controlled a virtual wheelchair during the second session; these same nine subjects achieved a medium accuracy level above 0.83 on the real wheelchair control session. The results suggest that more extensive training with the proposed control system can be an effective and safe option that will allow the displacement of a wheelchair in a controlled environment for potential users suffering from some types of motor neuron diseases.

  15. Programmable dc motor controller

    Science.gov (United States)

    Hopwood, J. E.

    1982-11-01

    A portable programmable dc motor controller, with features not available on commercial instruments was developed for controlling fixtures during welding processes. The controller can be used to drive any dc motor having tachometer feedback and motor requirements not exceeding 30 volts, 3 amperes. Among the controller's features are delayed start time, upslope time, speed, and downslope time.

  16. Body representations in the human brain revealed by kinesthetic illusions and their essential contributions to motor control and corporeal awareness.

    Science.gov (United States)

    Naito, Eiichi; Morita, Tomoyo; Amemiya, Kaoru

    2016-03-01

    The human brain can generate a continuously changing postural model of our body. Somatic (proprioceptive) signals from skeletal muscles and joints contribute to the formation of the body representation. Recent neuroimaging studies of proprioceptive bodily illusions have elucidated the importance of three brain systems (motor network, specialized parietal systems, right inferior fronto-parietal network) in the formation of the human body representation. The motor network, especially the primary motor cortex, processes afferent input from skeletal muscles. Such information may contribute to the formation of kinematic/dynamic postural models of limbs, thereby enabling fast online feedback control. Distinct parietal regions appear to play specialized roles in the transformation/integration of information across different coordinate systems, which may subserve the adaptability and flexibility of the body representation. Finally, the right inferior fronto-parietal network, connected by the inferior branch of the superior longitudinal fasciculus, is consistently recruited when an individual experiences various types of bodily illusions and its possible roles relate to corporeal awareness, which is likely elicited through a series of neuronal processes of monitoring and accumulating bodily information and updating the body representation. Because this network is also recruited when identifying one's own features, the network activity could be a neuronal basis for self-consciousness. Copyright © 2015 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  17. Post-stroke Rehabilitation Training with a Motor-Imagery-Based Brain-Computer Interface (BCI)-Controlled Hand Exoskeleton: A Randomized Controlled Multicenter Trial.

    Science.gov (United States)

    Frolov, Alexander A; Mokienko, Olesya; Lyukmanov, Roman; Biryukova, Elena; Kotov, Sergey; Turbina, Lydia; Nadareyshvily, Georgy; Bushkova, Yulia

    2017-01-01

    Repeated use of brain-computer interfaces (BCIs) providing contingent sensory feedback of brain activity was recently proposed as a rehabilitation approach to restore motor function after stroke or spinal cord lesions. However, there are only a few clinical studies that investigate feasibility and effectiveness of such an approach. Here we report on a placebo-controlled, multicenter clinical trial that investigated whether stroke survivors with severe upper limb (UL) paralysis benefit from 10 BCI training sessions each lasting up to 40 min. A total of 74 patients participated: median time since stroke is 8 months, 25 and 75% quartiles [3.0; 13.0]; median severity of UL paralysis is 4.5 points [0.0; 30.0] as measured by the Action Research Arm Test, ARAT, and 19.5 points [11.0; 40.0] as measured by the Fugl-Meyer Motor Assessment, FMMA. Patients in the BCI group ( n = 55) performed motor imagery of opening their affected hand. Motor imagery-related brain electroencephalographic activity was translated into contingent hand exoskeleton-driven opening movements of the affected hand. In a control group ( n = 19), hand exoskeleton-driven opening movements of the affected hand were independent of brain electroencephalographic activity. Evaluation of the UL clinical assessments indicated that both groups improved, but only the BCI group showed an improvement in the ARAT's grasp score from 0 [0.0; 14.0] to 3.0 [0.0; 15.0] points ( p exoskeleton-assisted physical therapy can improve post-stroke rehabilitation outcomes. Both maximum and mean values of the percentage of successfully decoded imagery-related EEG activity, were higher than chance level. A correlation between the classification accuracy and the improvement in the upper extremity function was found. An improvement of motor function was found for patients with different duration, severity and location of the stroke.

  18. Visuo-motor coordination ability predicts performance with brain-computer interfaces controlled by modulation of sensorimotor rhythms (SMR

    Directory of Open Access Journals (Sweden)

    Eva Maria Hammer

    2014-08-01

    Full Text Available Modulation of sensorimotor rhythms (SMR was suggested as a control signal for brain-computer interfaces (BCI. Yet, there is a population of users estimated between 10 to 50% not able to achieve reliable control and only about 20% of users achieve high (80-100% performance. Predicting performance prior to BCI use would facilitate selection of the most feasible system for an individual, thus constitute a practical benefit for the user, and increase our knowledge about the correlates of BCI control. In a recent study, we predicted SMR-BCI performance from psychological variables that were assessed prior to the BCI sessions and BCI control was supported with machine-learning techniques. We described two significant psychological predictors, namely the visuo-motor coordination ability and the ability to concentrate on the task. The purpose of the current study was to replicate these results thereby validating these predictors within a neurofeedback based SMR-BCI that involved no machine learning. Thirty-three healthy BCI novices participated in a calibration session and three further neurofeedback training sessions. Two variables were related with mean SMR-BCI performance: (1 A measure for the accuracy of fine motor skills, i.e. a trade for a person’s visuo-motor control ability and (2 subject’s attentional impulsivity. In a linear regression they accounted for almost 20% in variance of SMR-BCI performance, but predictor (1 failed significance. Nevertheless, on the basis of our prior regression model for sensorimotor control ability we could predict current SMR-BCI performance with an average prediction error of M = 12.07%. In more than 50% of the participants, the prediction error was smaller than 10%. Hence, psychological variables played a moderate role in predicting SMR-BCI performance in a neurofeedback approach that involved no machine learning. Future studies are needed to further consolidate (or reject the present predictors.

  19. Toward brain-actuated car applications: Self-paced control with a motor imagery-based brain-computer interface.

    Science.gov (United States)

    Yu, Yang; Zhou, Zongtan; Yin, Erwei; Jiang, Jun; Tang, Jingsheng; Liu, Yadong; Hu, Dewen

    2016-10-01

    This study presented a paradigm for controlling a car using an asynchronous electroencephalogram (EEG)-based brain-computer interface (BCI) and presented the experimental results of a simulation performed in an experimental environment outside the laboratory. This paradigm uses two distinct MI tasks, imaginary left- and right-hand movements, to generate a multi-task car control strategy consisting of starting the engine, moving forward, turning left, turning right, moving backward, and stopping the engine. Five healthy subjects participated in the online car control experiment, and all successfully controlled the car by following a previously outlined route. Subject S1 exhibited the most satisfactory BCI-based performance, which was comparable to the manual control-based performance. We hypothesize that the proposed self-paced car control paradigm based on EEG signals could potentially be used in car control applications, and we provide a complementary or alternative way for individuals with locked-in disorders to achieve more mobility in the future, as well as providing a supplementary car-driving strategy to assist healthy people in driving a car. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Effects of Multi-Session Repetitive Transcranial Magnetic Stimulation on Motor Control and Spontaneous Brain Activity in Multiple System Atrophy: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Zhu Liu

    2018-05-01

    Full Text Available Background: Impaired motor control is one of the most common symptoms of multiple system atrophy (MSA. It arises from dysfunction of the cerebellum and its connected neural networks, including the primary motor cortex (M1, and is associated with altered spontaneous (i.e., resting-state brain network activity. Non-invasive repetitive transcranial magnetic stimulation (rTMS selectively facilitates the excitability of supraspinal networks. Repeated rTMS sessions have been shown to induce long-term changes to both resting-state brain dynamics and behavior in several neurodegenerative diseases. Here, we hypothesized that a multi-session rTMS intervention would improve motor control in patients with MSA, and that such improvements would correlate with changes in resting-state brain activity.Methods: Nine participants with MSA received daily sessions of 5 Hz rTMS for 5 days. rTMS targeted both the cerebellum and the bilateral M1. Before and within 3 days after the intervention, motor control was assessed by the motor item of the Unified Multiple System Atrophy Rating Scale (UMSARS. Resting-state brain activity was recorded by blood-oxygen-level dependency (BOLD functional magnetic resonance imaging. The “complexity” of resting-state brain activity fluctuations was quantified within seven well-known functional cortical networks using multiscale entropy, a technique that estimates the degree of irregularity of the BOLD time-series across multiple scales of time.Results: The rTMS intervention was well-attended and was not associated with any adverse events. Average motor scores were lower (i.e., better performance following the rTMS intervention as compared to baseline (t8 = 2.3, p = 0.003. Seven of nine participants exhibited such pre-to-post intervention improvements. A trend toward an increase in resting-state complexity was observed within the motor network (t8 = 1.86, p = 0.07. Participants who exhibited greater increases in motor network resting

  1. Post-stroke Rehabilitation Training with a Motor-Imagery-Based Brain-Computer Interface (BCI-Controlled Hand Exoskeleton: A Randomized Controlled Multicenter Trial

    Directory of Open Access Journals (Sweden)

    Alexander A. Frolov

    2017-07-01

    Full Text Available Repeated use of brain-computer interfaces (BCIs providing contingent sensory feedback of brain activity was recently proposed as a rehabilitation approach to restore motor function after stroke or spinal cord lesions. However, there are only a few clinical studies that investigate feasibility and effectiveness of such an approach. Here we report on a placebo-controlled, multicenter clinical trial that investigated whether stroke survivors with severe upper limb (UL paralysis benefit from 10 BCI training sessions each lasting up to 40 min. A total of 74 patients participated: median time since stroke is 8 months, 25 and 75% quartiles [3.0; 13.0]; median severity of UL paralysis is 4.5 points [0.0; 30.0] as measured by the Action Research Arm Test, ARAT, and 19.5 points [11.0; 40.0] as measured by the Fugl-Meyer Motor Assessment, FMMA. Patients in the BCI group (n = 55 performed motor imagery of opening their affected hand. Motor imagery-related brain electroencephalographic activity was translated into contingent hand exoskeleton-driven opening movements of the affected hand. In a control group (n = 19, hand exoskeleton-driven opening movements of the affected hand were independent of brain electroencephalographic activity. Evaluation of the UL clinical assessments indicated that both groups improved, but only the BCI group showed an improvement in the ARAT's grasp score from 0 [0.0; 14.0] to 3.0 [0.0; 15.0] points (p < 0.01 and pinch scores from 0.0 [0.0; 7.0] to 1.0 [0.0; 12.0] points (p < 0.01. Upon training completion, 21.8% and 36.4% of the patients in the BCI group improved their ARAT and FMMA scores respectively. The corresponding numbers for the control group were 5.1% (ARAT and 15.8% (FMMA. These results suggests that adding BCI control to exoskeleton-assisted physical therapy can improve post-stroke rehabilitation outcomes. Both maximum and mean values of the percentage of successfully decoded imagery-related EEG activity, were higher

  2. Electrophysiological Brain Activity during the Control of a Motor Imagery-Based Brain–Computer Interface

    Czech Academy of Sciences Publication Activity Database

    Frolov, A. A.; Aziatskaya, G.A.; Bobrov, P.D.; Luykmanov, R. Kh.; Fedotova, I.R.; Húsek, Dušan; Snášel, V.

    2017-01-01

    Roč. 43, č. 5 (2017), s. 501-511 ISSN 0362-1197 Institutional support: RVO:67985807 Keywords : brain–computer interface * neurointerface * EEG * motor imagery * EEG rhythm synchronization and desynchronization * independent component analysis * EEG inverse problem * neurorehabilitation Subject RIV: IN - Informatics, Computer Science OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8)

  3. Motor control for a brushless DC motor

    Science.gov (United States)

    Peterson, William J. (Inventor); Faulkner, Dennis T. (Inventor)

    1985-01-01

    This invention relates to a motor control system for a brushless DC motor having an inverter responsively coupled to the motor control system and in power transmitting relationship to the motor. The motor control system includes a motor rotor speed detecting unit that provides a pulsed waveform signal proportional to rotor speed. This pulsed waveform signal is delivered to the inverter to thereby cause an inverter fundamental current waveform output to the motor to be switched at a rate proportional to said rotor speed. In addition, the fundamental current waveform is also pulse width modulated at a rate proportional to the rotor speed. A fundamental current waveform phase advance circuit is controllingly coupled to the inverter. The phase advance circuit is coupled to receive the pulsed waveform signal from the motor rotor speed detecting unit and phase advance the pulsed waveform signal as a predetermined function of motor speed to thereby cause the fundamental current waveform to be advanced and thereby compensate for fundamental current waveform lag due to motor winding reactance which allows the motor to operate at higher speeds than the motor is rated while providing optimal torque and therefore increased efficiency.

  4. Advanced AC Motor Control

    Energy Technology Data Exchange (ETDEWEB)

    Kazmierkowski, M.P. [Institute of Control and Industrial Electronics, Warsaw University of Technology, Warszawa (Poland)

    1997-12-31

    In this paper a review of control methods for high performance PWM inverter-fed induction motor drives is presented. Starting from the description of an induction motor by the help of the space vectors, three basic control strategic are discussed. As first, the most popular Field Oriented Control (FOC) is described. Secondly, the Direct Torque and Flux vector Control (DTFC) method, which - in contrast to FOC - depart from idea of coordinate transformation and analogy with DC motor, is briefly characterized. The last group is based on Feedback Linearization Control (FLC) and can be easy combined with sliding mode control. The simulation and experimental oscillograms that illustrate the performance of the discussed control strategies are shown. (orig.) 35 refs.

  5. Electric vehicle motors and controllers

    Science.gov (United States)

    Secunde, R. R.

    1981-01-01

    Improved and advanced components being developed include electronically commutated permanent magnet motors of both drum and disk configuration, an unconventional brush commutated motor, and ac induction motors and various controllers. Test results on developmental motors, controllers, and combinations thereof indicate that efficiencies of 90% and higher for individual components, and 80% to 90% for motor/controller combinations can be obtained at rated power. The simplicity of the developmental motors and the potential for ultimately low cost electronics indicate that one or more of these approaches to electric vehicle propulsion may eventually displace presently used controllers and brush commutated dc motors.

  6. Human spinal motor control

    DEFF Research Database (Denmark)

    Nielsen, Jens Bo

    2016-01-01

    Human studies in the past three decades have provided us with an emerging understanding of how cortical and spinal networks collaborate to ensure the vast repertoire of human behaviors. We differ from other animals in having direct cortical connections to spinal motoneurons, which bypass spinal...... the central motor command by opening or closing sensory feedback pathways. In the future, human studies of spinal motor control, in close collaboration with animal studies on the molecular biology of the spinal cord, will continue to document the neural basis for human behavior. Expected final online...

  7. Combined EEG-fNIRS decoding of motor attempt and imagery for brain switch control: an offline study in patients with tetraplegia.

    Science.gov (United States)

    Blokland, Yvonne; Spyrou, Loukianos; Thijssen, Dick; Eijsvogels, Thijs; Colier, Willy; Floor-Westerdijk, Marianne; Vlek, Rutger; Bruhn, Jorgen; Farquhar, Jason

    2014-03-01

    Combining electrophysiological and hemodynamic features is a novel approach for improving current performance of brain switches based on sensorimotor rhythms (SMR). This study was conducted with a dual purpose: to test the feasibility of using a combined electroencephalogram/functional near-infrared spectroscopy (EEG-fNIRS) SMR-based brain switch in patients with tetraplegia, and to examine the performance difference between motor imagery and motor attempt for this user group. A general improvement was found when using both EEG and fNIRS features for classification as compared to using the single-modality EEG classifier, with average classification rates of 79% for attempted movement and 70% for imagined movement. For the control group, rates of 87% and 79% were obtained, respectively, where the "attempted movement" condition was replaced with "actual movement." A combined EEG-fNIRS system might be especially beneficial for users who lack sufficient control of current EEG-based brain switches. The average classification performance in the patient group for attempted movement was significantly higher than for imagined movement using the EEG-only as well as the combined classifier, arguing for the case of a paradigm shift in current brain switch research.

  8. Control of synchronous motors

    CERN Document Server

    Louis, Jean-Paul

    2013-01-01

    Synchronous motors are indubitably the most effective device to drive industrial production systems and robots with precision and rapidity. Their control law is thus critical for combining at the same time high productivity to reduced energy consummation. As far as possible, the control algorithms must exploit the properties of these actuators. Therefore, this work draws on well adapted models resulting from the Park's transformation, for both the most traditional machines with sinusoidal field distribution and for machines with non-sinusoidal field distribution which are more and more used in

  9. The kinematic portrait of a patient as an objective indicator of motor function in the process of neurorehabilitation with hand exoskeleton controlled by the brain – computer interface

    Directory of Open Access Journals (Sweden)

    А. А. Kondur

    2016-01-01

    Full Text Available The results of biomechanical analysis of the motor function of the arm of poststroke patient in the process of neuroreha bilitation with exoskeleton of the hand controlled by brain – computer interface are presented in this paper. At the beginning and end of the course it was registered the kinematic portrait of the patient– isolated random movements for each of the seven degrees of freedom as the paretic and intact arms.Angular accelerations were taken as an assessment of muscle forces, the number of reverse movements was taken as an assessment of joint spasticity, and the kinematic content of the movement as a description of pathological synergy arising after stroke. These parameters give an objective numerical asses sment of motor function as well as of rehabilitation technology effectiveness.

  10. Microprocessor controller for stepping motors

    International Nuclear Information System (INIS)

    Strait, B.G.; Thuot, M.E.

    1977-01-01

    A new concept for digital computer control of multiple stepping motors which operate in a severe electromagnetic pulse environment is presented. The motors position mirrors in the beam-alignment system of a 100-kJ CO 2 laser. An asynchronous communications channel of a computer is used to send coded messages, containing the motor address and stepping-command information, to the stepping-motor controller in a bit serial format over a fiber-optics communications link. The addressed controller responds by transmitting to the computer its address and other motor information, thus confirming the received message. Each controller is capable of controlling three stepping motors. The controller contains the fiber-optics interface, a microprocessor, and the stepping-motor driven circuits. The microprocessor program, which resides in an EPROM, decodes the received messages, transmits responses, performs the stepping-motor sequence logic, maintains motor-position information, and monitors the motor's reference switch. For multiple stepping-motor application, the controllers are connected in a daisy chain providing control of many motors from one asynchronous communications channel of the computer

  11. Quadcopter control in three-dimensional space using a noninvasive motor imagery based brain-computer interface

    Science.gov (United States)

    LaFleur, Karl; Cassady, Kaitlin; Doud, Alexander; Shades, Kaleb; Rogin, Eitan; He, Bin

    2013-01-01

    Objective At the balanced intersection of human and machine adaptation is found the optimally functioning brain-computer interface (BCI). In this study, we report a novel experiment of BCI controlling a robotic quadcopter in three-dimensional physical space using noninvasive scalp EEG in human subjects. We then quantify the performance of this system using metrics suitable for asynchronous BCI. Lastly, we examine the impact that operation of a real world device has on subjects’ control with comparison to a two-dimensional virtual cursor task. Approach Five human subjects were trained to modulate their sensorimotor rhythms to control an AR Drone navigating a three-dimensional physical space. Visual feedback was provided via a forward facing camera on the hull of the drone. Individual subjects were able to accurately acquire up to 90.5% of all valid targets presented while travelling at an average straight-line speed of 0.69 m/s. Significance Freely exploring and interacting with the world around us is a crucial element of autonomy that is lost in the context of neurodegenerative disease. Brain-computer interfaces are systems that aim to restore or enhance a user’s ability to interact with the environment via a computer and through the use of only thought. We demonstrate for the first time the ability to control a flying robot in the three-dimensional physical space using noninvasive scalp recorded EEG in humans. Our work indicates the potential of noninvasive EEG based BCI systems to accomplish complex control in three-dimensional physical space. The present study may serve as a framework for the investigation of multidimensional non-invasive brain-computer interface control in a physical environment using telepresence robotics. PMID:23735712

  12. Quadcopter control in three-dimensional space using a noninvasive motor imagery-based brain-computer interface

    Science.gov (United States)

    LaFleur, Karl; Cassady, Kaitlin; Doud, Alexander; Shades, Kaleb; Rogin, Eitan; He, Bin

    2013-08-01

    Objective. At the balanced intersection of human and machine adaptation is found the optimally functioning brain-computer interface (BCI). In this study, we report a novel experiment of BCI controlling a robotic quadcopter in three-dimensional (3D) physical space using noninvasive scalp electroencephalogram (EEG) in human subjects. We then quantify the performance of this system using metrics suitable for asynchronous BCI. Lastly, we examine the impact that the operation of a real world device has on subjects' control in comparison to a 2D virtual cursor task. Approach. Five human subjects were trained to modulate their sensorimotor rhythms to control an AR Drone navigating a 3D physical space. Visual feedback was provided via a forward facing camera on the hull of the drone. Main results. Individual subjects were able to accurately acquire up to 90.5% of all valid targets presented while travelling at an average straight-line speed of 0.69 m s-1. Significance. Freely exploring and interacting with the world around us is a crucial element of autonomy that is lost in the context of neurodegenerative disease. Brain-computer interfaces are systems that aim to restore or enhance a user's ability to interact with the environment via a computer and through the use of only thought. We demonstrate for the first time the ability to control a flying robot in 3D physical space using noninvasive scalp recorded EEG in humans. Our work indicates the potential of noninvasive EEG-based BCI systems for accomplish complex control in 3D physical space. The present study may serve as a framework for the investigation of multidimensional noninvasive BCI control in a physical environment using telepresence robotics.

  13. 46 CFR 111.70-3 - Motor controllers and motor-control centers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Motor controllers and motor-control centers. 111.70-3... ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Motor Circuits, Controllers, and Protection § 111.70-3 Motor controllers and motor-control centers. (a) General. The enclosure for each motor controller or motor-control...

  14. The neural optimal control hierarchy for motor control

    Science.gov (United States)

    DeWolf, T.; Eliasmith, C.

    2011-10-01

    Our empirical, neuroscientific understanding of biological motor systems has been rapidly growing in recent years. However, this understanding has not been systematically mapped to a quantitative characterization of motor control based in control theory. Here, we attempt to bridge this gap by describing the neural optimal control hierarchy (NOCH), which can serve as a foundation for biologically plausible models of neural motor control. The NOCH has been constructed by taking recent control theoretic models of motor control, analyzing the required processes, generating neurally plausible equivalent calculations and mapping them on to the neural structures that have been empirically identified to form the anatomical basis of motor control. We demonstrate the utility of the NOCH by constructing a simple model based on the identified principles and testing it in two ways. First, we perturb specific anatomical elements of the model and compare the resulting motor behavior with clinical data in which the corresponding area of the brain has been damaged. We show that damaging the assigned functions of the basal ganglia and cerebellum can cause the movement deficiencies seen in patients with Huntington's disease and cerebellar lesions. Second, we demonstrate that single spiking neuron data from our model's motor cortical areas explain major features of single-cell responses recorded from the same primate areas. We suggest that together these results show how NOCH-based models can be used to unify a broad range of data relevant to biological motor control in a quantitative, control theoretic framework.

  15. 'Motor control center obsolescence'

    International Nuclear Information System (INIS)

    Irish, C.S.

    2003-01-01

    A significant and growing problem within the global nuclear industry is the aging of motor control center (MCC) components. MCC's have a very important role in the safety and critical to generation requirements of a nuclear power plant. Although many OEM's MCC's such as ITE/Telemechanique, GE, Westinghouse, Cutler Hammer, Klockner Moeller, etc. have been used throughout the global nuclear industry, they all have one common aspect obsolescence. Obsolescence of various components within the MCC's such as molded case circuit breakers, starters, relays, heaters, contactors, etc. are impacting the reliability of the MCC to serve its intended function. The paper will discuss the options which the nuclear industry is faced with to increase the reliability of the MCC's while maintaining design control, qualification and meeting budget constraints. The options as listed below shall be discussed in detail with examples to enhance the readers understanding of the situation: 1) Component by component replacement: The hurdles associated with trying to find equivalent components to replace the obsolete components while still worki (mechanically and electrically) in the original cubicle will be presented. 2) Complete MCC cubicle with new internal components replacement: The process of supplying a replacement cubicle, with all new internal components and new door to replace the original cubicle will be discussed. The presentation will conclude with a comparison of the advantages and dis-advantages of the two methods to bring the MCC to an as new condition with the overall goal of increasing reliability. (author)

  16. A real-time brain-machine interface combining motor target and trajectory intent using an optimal feedback control design.

    Directory of Open Access Journals (Sweden)

    Maryam M Shanechi

    Full Text Available Real-time brain-machine interfaces (BMI have focused on either estimating the continuous movement trajectory or target intent. However, natural movement often incorporates both. Additionally, BMIs can be modeled as a feedback control system in which the subject modulates the neural activity to move the prosthetic device towards a desired target while receiving real-time sensory feedback of the state of the movement. We develop a novel real-time BMI using an optimal feedback control design that jointly estimates the movement target and trajectory of monkeys in two stages. First, the target is decoded from neural spiking activity before movement initiation. Second, the trajectory is decoded by combining the decoded target with the peri-movement spiking activity using an optimal feedback control design. This design exploits a recursive Bayesian decoder that uses an optimal feedback control model of the sensorimotor system to take into account the intended target location and the sensory feedback in its trajectory estimation from spiking activity. The real-time BMI processes the spiking activity directly using point process modeling. We implement the BMI in experiments consisting of an instructed-delay center-out task in which monkeys are presented with a target location on the screen during a delay period and then have to move a cursor to it without touching the incorrect targets. We show that the two-stage BMI performs more accurately than either stage alone. Correct target prediction can compensate for inaccurate trajectory estimation and vice versa. The optimal feedback control design also results in trajectories that are smoother and have lower estimation error. The two-stage decoder also performs better than linear regression approaches in offline cross-validation analyses. Our results demonstrate the advantage of a BMI design that jointly estimates the target and trajectory of movement and more closely mimics the sensorimotor control system.

  17. User Experience May be Producing Greater Heart Rate Variability than Motor Imagery Related Control Tasks during the User-System Adaptation in Brain-Computer Interfaces

    Science.gov (United States)

    Alonso-Valerdi, Luz M.; Gutiérrez-Begovich, David A.; Argüello-García, Janet; Sepulveda, Francisco; Ramírez-Mendoza, Ricardo A.

    2016-01-01

    Brain-computer interface (BCI) is technology that is developing fast, but it remains inaccurate, unreliable and slow due to the difficulty to obtain precise information from the brain. Consequently, the involvement of other biosignals to decode the user control tasks has risen in importance. A traditional way to operate a BCI system is via motor imagery (MI) tasks. As imaginary movements activate similar cortical structures and vegetative mechanisms as a voluntary movement does, heart rate variability (HRV) has been proposed as a parameter to improve the detection of MI related control tasks. However, HR is very susceptible to body needs and environmental demands, and as BCI systems require high levels of attention, perceptual processing and mental workload, it is important to assess the practical effectiveness of HRV. The present study aimed to determine if brain and heart electrical signals (HRV) are modulated by MI activity used to control a BCI system, or if HRV is modulated by the user perceptions and responses that result from the operation of a BCI system (i.e., user experience). For this purpose, a database of 11 participants who were exposed to eight different situations was used. The sensory-cognitive load (intake and rejection tasks) was controlled in those situations. Two electrophysiological signals were utilized: electroencephalography and electrocardiography. From those biosignals, event-related (de-)synchronization maps and event-related HR changes were respectively estimated. The maps and the HR changes were cross-correlated in order to verify if both biosignals were modulated due to MI activity. The results suggest that HR varies according to the experience undergone by the user in a BCI working environment, and not because of the MI activity used to operate the system. PMID:27458384

  18. Torque control for electric motors

    Science.gov (United States)

    Bernard, C. A.

    1980-01-01

    Method for adjusting electric-motor torque output to accomodate various loads utilizes phase-lock loop to control relay connected to starting circuit. As load is imposed, motor slows down, and phase lock is lost. Phase-lock signal triggers relay to power starting coil and generate additional torque. Once phase lock is recoverd, relay restores starting circuit to its normal operating mode.

  19. Increased motor cortex excitability during motor imagery in brain-computer interface trained subjects

    Science.gov (United States)

    Mokienko, Olesya A.; Chervyakov, Alexander V.; Kulikova, Sofia N.; Bobrov, Pavel D.; Chernikova, Liudmila A.; Frolov, Alexander A.; Piradov, Mikhail A.

    2013-01-01

    Background: Motor imagery (MI) is the mental performance of movement without muscle activity. It is generally accepted that MI and motor performance have similar physiological mechanisms. Purpose: To investigate the activity and excitability of cortical motor areas during MI in subjects who were previously trained with an MI-based brain-computer interface (BCI). Subjects and Methods: Eleven healthy volunteers without neurological impairments (mean age, 36 years; range: 24–68 years) were either trained with an MI-based BCI (BCI-trained, n = 5) or received no BCI training (n = 6, controls). Subjects imagined grasping in a blocked paradigm task with alternating rest and task periods. For evaluating the activity and excitability of cortical motor areas we used functional MRI and navigated transcranial magnetic stimulation (nTMS). Results: fMRI revealed activation in Brodmann areas 3 and 6, the cerebellum, and the thalamus during MI in all subjects. The primary motor cortex was activated only in BCI-trained subjects. The associative zones of activation were larger in non-trained subjects. During MI, motor evoked potentials recorded from two of the three targeted muscles were significantly higher only in BCI-trained subjects. The motor threshold decreased (median = 17%) during MI, which was also observed only in BCI-trained subjects. Conclusion: Previous BCI training increased motor cortex excitability during MI. These data may help to improve BCI applications, including rehabilitation of patients with cerebral palsy. PMID:24319425

  20. Increased motor cortex excitability during motor imagery in brain-computer interface trained subjects

    Directory of Open Access Journals (Sweden)

    Olesya eMokienko

    2013-11-01

    Full Text Available Background: Motor imagery (MI is the mental performance of movement without muscle activity. It is generally accepted that MI and motor performance have similar physiological mechanisms.Purpose: To investigate the activity and excitability of cortical motor areas during MI in subjects who were previously trained with an MI-based brain-computer interface (BCI.Subjects and methods: Eleven healthy volunteers without neurological impairments (mean age, 36 years; range: 24–68 years were either trained with an MI-based BCI (BCI-trained, n = 5 or received no BCI training (n = 6, controls. Subjects imagined grasping in a blocked paradigm task with alternating rest and task periods. For evaluating the activity and excitability of cortical motor areas we used functional MRI and navigated transcranial magnetic stimulation (nTMS.Results: fMRI revealed activation in Brodmann areas 3 and 6, the cerebellum, and the thalamus during MI in all subjects. The primary motor cortex was activated only in BCI-trained subjects. The associative zones of activation were larger in non-trained subjects. During MI, motor evoked potentials recorded from two of the three targeted muscles were significantly higher only in BCI-trained subjects. The motor threshold decreased (median = 17% during MI, which was also observed only in BCI-trained subjects.Conclusion: Previous BCI training increased motor cortex excitability during MI. These data may help to improve BCI applications, including rehabilitation of patients with cerebral palsy.

  1. A versatile stepping motor controller for systems with many motors

    International Nuclear Information System (INIS)

    Feng, S.K.; Siddons, D.P.

    1989-01-01

    A versatile system for controlling beamlines or complex experimental setups is described. The system as currently configured can control up to 32 motors, with all motors capable of full speed operation concurrently. There are 2 limit switch inputs for each motor, and a further input to accept a reference position marker. The motors can be controlled via a front panel keyboard with display, or by a host computer over an IEEE-488 interface. Both methods can be used together if required. There is an ''emergency stop'' key on the front panel keyboard to stop the motion of all motors without losing track of the motors' position. 3 refs., 4 figs., 1 tab

  2. Motor sequence learning-induced neural efficiency in functional brain connectivity.

    Science.gov (United States)

    Karim, Helmet T; Huppert, Theodore J; Erickson, Kirk I; Wollam, Mariegold E; Sparto, Patrick J; Sejdić, Ervin; VanSwearingen, Jessie M

    2017-02-15

    Previous studies have shown the functional neural circuitry differences before and after an explicitly learned motor sequence task, but have not assessed these changes during the process of motor skill learning. Functional magnetic resonance imaging activity was measured while participants (n=13) were asked to tap their fingers to visually presented sequences in blocks that were either the same sequence repeated (learning block) or random sequences (control block). Motor learning was associated with a decrease in brain activity during learning compared to control. Lower brain activation was noted in the posterior parietal association area and bilateral thalamus during the later periods of learning (not during the control). Compared to the control condition, we found the task-related motor learning was associated with decreased connectivity between the putamen and left inferior frontal gyrus and left middle cingulate brain regions. Motor learning was associated with changes in network activity, spatial extent, and connectivity. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Brain control and information transfer.

    Science.gov (United States)

    Tehovnik, Edward J; Chen, Lewis L

    2015-12-01

    In this review, we examine the importance of having a body as essential for the brain to transfer information about the outside world to generate appropriate motor responses. We discuss the context-dependent conditioning of the motor control neural circuits and its dependence on the completion of feedback loops, which is in close agreement with the insights of Hebb and colleagues, who have stressed that for learning to occur the body must be intact and able to interact with the outside world. Finally, we apply information theory to data from published studies to evaluate the robustness of the neuronal signals obtained by bypassing the body (as used for brain-machine interfaces) versus via the body to move in the world. We show that recording from a group of neurons that bypasses the body exhibits a vastly degraded level of transfer of information as compared to that of an entire brain using the body to engage in the normal execution of behaviour. We conclude that body sensations provide more than just feedback for movements; they sustain the necessary transfer of information as animals explore their environment, thereby creating associations through learning. This work has implications for the development of brain-machine interfaces used to move external devices.

  4. Optimization analysis of propulsion motor control efficiency

    Directory of Open Access Journals (Sweden)

    CAI Qingnan

    2017-12-01

    Full Text Available [Objectives] This paper aims to strengthen the control effect of propulsion motors and decrease the energy used during actual control procedures.[Methods] Based on the traditional propulsion motor equivalence circuit, we increase the iron loss current component, introduce the definition of power matching ratio, calculate the highest efficiency of a motor at a given speed and discuss the flux corresponding to the power matching ratio with the highest efficiency. In the original motor vector efficiency optimization control module, an efficiency optimization control module is added so as to achieve motor efficiency optimization and energy conservation.[Results] MATLAB/Simulink simulation data shows that the efficiency optimization control method is suitable for most conditions. The operation efficiency of the improved motor model is significantly higher than that of the original motor model, and its dynamic performance is good.[Conclusions] Our motor efficiency optimization control method can be applied in engineering to achieve energy conservation.

  5. Control of non-conventional synchronous motors

    CERN Document Server

    Louis, Jean-Paul

    2013-01-01

    Classical synchronous motors are the most effective device to drive industrial production systems and robots with precision and rapidity. However, numerous applications require efficient controls in non-conventional situations. Firstly, this is the case with synchronous motors supplied by thyristor line-commutated inverters, or with synchronous motors with faults on one or several phases. Secondly, many drive systems use non-conventional motors such as polyphase (more than three phases) synchronous motors, synchronous motors with double excitation, permanent magnet linear synchronous motors,

  6. The micro-step motor controller

    International Nuclear Information System (INIS)

    Hong, Kwang Pyo; Lee, Chang Hee; Moon, Myung Kook; Choi, Bung Hun; Choi, Young Hyun; Cheon, Jong Gu

    2004-11-01

    The developed micro-step motor controller can handle 4 axes stepping motor drivers simultaneously and provide high power bipolar driving mechanism with constant current mode. It can be easily controlled by manual key functions and the motor driving status is displayed by the front panel VFD. Due to the development of several kinds of communication and driving protocol, PC can operate even several micro-step motor controllers at once by multi-drop connection

  7. Conceptual design of stepper motor replacing servo motor for control rod controller

    International Nuclear Information System (INIS)

    Mohd Dzul Aiman Aslan; Mohd Idris Taib; Izhar Abu Hussin; Mohd Khairulezwan Abdul Manan; Mohd Sabri Minhat

    2010-01-01

    In PUSPATI TRIGA Reactor, current control rod controller are using servo motor to control the movement. Control rod is a very important safety element and measure in every nuclear reactor. So, precision is very important in measurement of security in the nuclear reactor. In this case, there are a few disadvantages when using the servo motor is measurement of the motor is not precise. One solution to overcome this is by shifting servo motor with stepper motor. A stepper motor (or step motor) is a brush less, synchronous electric motor that can divide a full rotation into a large number of steps. (author)

  8. Control of a superconducting synchronous motor

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Y; Pei, R; Jiang, Q; Hong, Z; Coombs, T A [Engineering Department, Cambridge University, Trumpington Street, Cambridge CB2 1PZ (United Kingdom)

    2007-04-15

    This paper presents a control algorithm for starting up a high temperature superconducting synchronous motor. The mathematical model of the motor has been established in m-file in Matlab and the parameters have been identified by means of the finite-element analysis method. Different starting methods for the motor have been compared and discussed, and eventually a hybrid control algorithm is proposed.

  9. Control of permanent magnet synchronous motors

    CERN Document Server

    Vaez-Zadeh, Sadegh

    2018-01-01

    This is the first comprehensive, coherent, and up-to-date book devoted solely to the control of permanent magnet synchronous (PMS) motors, as the fastest growing AC motor. It covers a deep and detailed presentation of major PMS motor modeling and control methods. The readers can find rich materials on the fundamentals of PMS motor control in addition to new motor control methods, which have mainly been developed in the last two decades, including recent advancements in the field in a systematic manner. These include extensive modeling of PMS motors and a full range of vector control and direct torque control schemes, in addition to predictive control, deadbeat control, and combined control methods. All major sensorless control and parameter estimation methods are also studied. The book covers about 10 machine models in various reference frames and 70 control and estimation schemes with sufficient analytical and implementation details including about 200 original figures. A great emphasis is placed on energy-s...

  10. One hand clapping: lateralization of motor control

    Directory of Open Access Journals (Sweden)

    Quentin eWelniarz

    2015-06-01

    Full Text Available Lateralization of motor control refers to the ability to produce pure unilateral or asymmetric movements. It is required for a variety of coordinated activities, including skilled bimanual tasks and locomotion. Here we discuss the neuroanatomical substrates and pathophysiological underpinnings of lateralized motor outputs. Significant breakthroughs have been made in the past few years by studying the two known conditions characterized by the inability to properly produce unilateral or asymmetric movements, namely human patients with congenital mirror movements and model rodents with a hopping gait. Whereas mirror movements are associated with altered interhemispheric connectivity and abnormal corticospinal projections, abnormal spinal cord interneurons trajectory is responsible for the hopping gait. Proper commissural axon guidance is a critical requirement for these mechanisms. Interestingly, the analysis of these two conditions reveals that the production of asymmetric movements involves similar anatomical and functional requirements but in two different structures: i lateralized activation of the brain or spinal cord through contralateral silencing by cross-midline inhibition; and ii unilateral transmission of this activation, resulting in lateralized motor output.

  11. Coupling brain-machine interfaces with cortical stimulation for brain-state dependent stimulation: enhancing motor cortex excitability for neurorehabilitation

    Directory of Open Access Journals (Sweden)

    Alireza eGharabaghi

    2014-03-01

    Full Text Available Motor recovery after stroke is an unsolved challenge despite intensive rehabilitation training programs. Brain stimulation techniques have been explored in addition to traditional rehabilitation training to increase the excitability of the stimulated motor cortex. This modulation of cortical excitability augments the response to afferent input during motor exercises, thereby enhancing skilled motor learning by long-term potentiation-like plasticity. Recent approaches examined brain stimulation applied concurrently with voluntary movements to induce more specific use-dependent neural plasticity during motor training for neurorehabilitation. Unfortunately, such approaches are not applicable for the many severely affected stroke patients lacking residual hand function. These patients require novel activity-dependent stimulation paradigms based on intrinsic brain activity. Here, we report on such brain state-dependent stimulation (BSDS combined with haptic feedback provided by a robotic hand orthosis. Transcranial magnetic stimulation of the motor cortex and haptic feedback to the hand were controlled by sensorimotor desynchronization during motor-imagery and applied within a brain-machine interface environment in one healthy subject and one patient with severe hand paresis in the chronic phase after stroke. BSDS significantly increased the excitability of the stimulated motor cortex in both healthy and post-stroke conditions, an effect not observed in non-BSDS protocols. This feasibility study suggests that closing the loop between intrinsic brain state, cortical stimulation and haptic feedback provides a novel neurorehabilitation strategy for stroke patients lacking residual hand function, a proposal that warrants further investigation in a larger cohort of stroke patients.

  12. Energy Optimal Control of Induction Motor Drives

    DEFF Research Database (Denmark)

    Abrahamsen, Flemming

    This thesis deals with energy optimal control of small and medium-size variable speed induction motor drives for especially Heating, Ventilation and Air-Condition (HVAC) applications. Optimized efficiency is achieved by adapting the magnetization level in the motor to the load, and the basic...... demonstrated that energy optimal control will sometimes improve and sometimes deteriorate the stability. Comparison of small and medium-size induction motor drives with permanent magnet motor drives indicated why, and in which applications, PM motors are especially good. Calculations of economical aspects...... improvement by energy optimal control for any standard induction motor drive between 2.2 kW and 90 kW. A simple method to evaluate the robustness against load disturbances was developed and used to compare the robustness of different motor types and sizes. Calculation of the oscillatory behavior of a motor...

  13. Ipsilateral motor pathways after stroke: implications for noninvasive brain stimulation

    Directory of Open Access Journals (Sweden)

    Lynley V Bradnam

    2013-05-01

    Full Text Available In humans the two cerebral hemispheres have essential roles in controlling the upper limb. The purpose of this article is to draw attention to the potential importance of ipsilateral descending pathways for functional recovery after stroke, and the use of noninvasive brain stimulation (NBS protocols of the contralesional primary motor cortex (M1. Conventionally NBS is used to suppress contralesional M1, and to attenuate transcallosal inhibition onto the ipsilesional M1. There has been little consideration of the fact that contralesional M1 suppression may also reduce excitability of ipsilateral descending pathways that may be important for paretic upper limb control for some patients. One such ipsilateral pathway is the cortico-reticulo-propriospinal pathway (CRPP. In this review we outline a neurophysiological model to explain how contralesional M1 may gain control of the paretic arm via the CRPP. We conclude that the relative importance of the CRPP for motor control in individual patients must be considered before using NBS to suppress contralesional M1. Neurophysiological, neuroimaging and clinical assessments can assist this decision making and facilitate the translation of NBS into the clinical setting.

  14. control of a dc motor using fuzzy logic control algorithm

    African Journals Online (AJOL)

    user

    controller in the control performance of an industrial type DC motor using MATLAB. The fuzzy logic .... controlled separately excited permanent magnet DC motor (PMDC). ... When the field current is constant, the flux induced by the field ...

  15. Functional MR imaging using sensory and motor task in brain tumors and other focal cerebral lesions

    International Nuclear Information System (INIS)

    Ok, Chul Su; Lim, Myung Kwan; Yu, Ki Bong; Kim, Hyung Jin; Suh, Chang Hae

    2002-01-01

    To determine the usefulness of the functional MRI (fMRI) using motor and sensory stimuli in patients with brain tumors of focal cerebral lesions. This study involved five patients with brain tumors (n=2) or cerebral lesions (cysticercosis (n=1), arteriovenous malformation (n=1), focal infarction (n=1) and seven normal controls. For MR examinations a 1.5T scanner was used, and during motor or sensory stimulation, the EPI BOLD technique was employed. For image postprocessing an SPM program was utilized. In volunteers, contralateral sensori-motor cortices were activated by both motor and sensory stimuli, while supplementary motor cortices were activated by motor stimuli and other sensory cortices by sensory stimuli. Preoperative evaluation of the relationship between lesions and important sensory and motor areas was possible, and subsequent surgery was thus successful, involving no severe complications. Activation of ipsilateral or other areas occurred in patients with destruction of a major sensory and/or motor area, suggesting compensatory reorganization. fMRI could be a useful supportive method for determining the best approach to surgery treatment in patients with brain tumors or focal cerebral lesions

  16. Motor areas of the frontal cortex in patients with motor eloquent brain lesions.

    Science.gov (United States)

    Bulubas, Lucia; Sabih, Jamil; Wohlschlaeger, Afra; Sollmann, Nico; Hauck, Theresa; Ille, Sebastian; Ringel, Florian; Meyer, Bernhard; Krieg, Sandro M

    2016-12-01

    OBJECTIVE Because of its huge clinical potential, the importance of premotor areas for motor function itself and plastic reshaping due to tumors or ischemic brain lesions has received increased attention. Thus, in this study the authors used navigated transcranial magnetic stimulation (nTMS) to investigate whether tumorous brain lesions induce a change in motor cortex localization in the human brain. METHODS Between 2010 and 2013, nTMS motor mapping was performed in a prospective cohort of 100 patients with brain tumors in or adjacent to the rolandic cortex. Spatial data analysis was performed by normalization of the individual motor maps and creation of overlays according to tumor location. Analysis of motor evoked potential (MEP) latencies was performed regarding mean overall latencies and potentially polysynaptic latencies, defined as latencies longer than 1 SD above the mean value. Hemispheric dominance, lesion location, and motor-function deficits were also considered. RESULTS Graphical analysis showed that motor areas were not restricted to the precentral gyrus. Instead, they spread widely in the anterior-posterior direction. An analysis of MEP latency showed that mean MEP latencies were shortest in the precentral gyrus and longest in the superior and middle frontal gyri. The percentage of latencies longer than 1 SD differed widely across gyri. The dominant hemisphere showed a greater number of longer latencies than the nondominant hemisphere (p < 0.0001). Moreover, tumor location-dependent changes in distribution of polysynaptic latencies were observed (p = 0.0002). Motor-function deficit did not show any statistically significant effect. CONCLUSIONS The distribution of primary and polysynaptic motor areas changes in patients with brain tumors and highly depends on tumor location. Thus, these data should be considered for resection planning.

  17. Functional connectivity between somatosensory and motor brain areas predicts individual differences in motor learning by observing.

    Science.gov (United States)

    McGregor, Heather R; Gribble, Paul L

    2017-08-01

    Action observation can facilitate the acquisition of novel motor skills; however, there is considerable individual variability in the extent to which observation promotes motor learning. Here we tested the hypothesis that individual differences in brain function or structure can predict subsequent observation-related gains in motor learning. Subjects underwent an anatomical MRI scan and resting-state fMRI scans to assess preobservation gray matter volume and preobservation resting-state functional connectivity (FC), respectively. On the following day, subjects observed a video of a tutor adapting her reaches to a novel force field. After observation, subjects performed reaches in a force field as a behavioral assessment of gains in motor learning resulting from observation. We found that individual differences in resting-state FC, but not gray matter volume, predicted postobservation gains in motor learning. Preobservation resting-state FC between left primary somatosensory cortex and bilateral dorsal premotor cortex, primary motor cortex, and primary somatosensory cortex and left superior parietal lobule was positively correlated with behavioral measures of postobservation motor learning. Sensory-motor resting-state FC can thus predict the extent to which observation will promote subsequent motor learning. NEW & NOTEWORTHY We show that individual differences in preobservation brain function can predict subsequent observation-related gains in motor learning. Preobservation resting-state functional connectivity within a sensory-motor network may be used as a biomarker for the extent to which observation promotes motor learning. This kind of information may be useful if observation is to be used as a way to boost neuroplasticity and sensory-motor recovery for patients undergoing rehabilitation for diseases that impair movement such as stroke. Copyright © 2017 the American Physiological Society.

  18. Microcomputer-based stepping-motor controller

    International Nuclear Information System (INIS)

    Johnson, K.

    1983-04-01

    A microcomputer-controlled stepping motor is described. A Motorola MC68701 microcomputer unit is interfaced to a Cybernetic CY500 stored-program controller that outputs through Motorola input/output isolation modules to the stepping motor. A complex multifunction controller with enhanced capabilities is thus available with a minimum number of parts

  19. Motor-related brain abnormalities in HIV-infected patients. A multimodal MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yawen; Wang, Xiaoxiao; Miao, Hui; Wei, Yarui; Ali, Rizwan [University of Science and Technology of China, Centers for Biomedical Engineering, Hefei, Anhui (China); Li, Ruili; Li, Hongjun [Capital Medical University, Department of Radiology, Beijing Youan Hospital, Beijing (China); Qiu, Bensheng [University of Science and Technology of China, Centers for Biomedical Engineering, Hefei, Anhui (China); Anhui Computer Application Institute of Traditional Chinese Medicine, Hefei, Anhui (China)

    2017-11-15

    It is generally believed that HIV infection could cause HIV-associated neurocognitive disorders (HAND) across a broad range of functional domains. Some of the most common findings are deficits in motor control. However, to date no neuroimaging studies have evaluated basic motor control in HIV-infected patients using a multimodal approach. In this study, we utilized high-resolution structural imaging and task-state functional magnetic resonance imaging (fMRI) to assess brain structure and motor function in a homogeneous cohort of HIV-infected patients. We found that HIV-infected patients had significantly reduced gray matter (GM) volume in cortical regions, which are involved in motor control, including the bilateral posterior insula cortex, premotor cortex, and supramarginal gyrus. Increased activation in bilateral posterior insula cortices was also demonstrated by patients during hand movement tasks compared with healthy controls. More importantly, the reduced GM in bilateral posterior insula cortices was spatially coincident with abnormal brain activation in HIV-infected patients. In addition, the results of partial correlation analysis indicated that GM reduction in bilateral posterior insula cortices and premotor cortices was significantly correlated with immune system deterioration. This study is the first to demonstrate spatially coincident GM reduction and abnormal activation during motor performance in HIV-infected patients. Although it remains unknown whether the brain deficits can be recovered, our findings may yield new insights into neurologic injury underlying motor dysfunction in HAND. (orig.)

  20. Motor-related brain abnormalities in HIV-infected patients. A multimodal MRI study

    International Nuclear Information System (INIS)

    Zhou, Yawen; Wang, Xiaoxiao; Miao, Hui; Wei, Yarui; Ali, Rizwan; Li, Ruili; Li, Hongjun; Qiu, Bensheng

    2017-01-01

    It is generally believed that HIV infection could cause HIV-associated neurocognitive disorders (HAND) across a broad range of functional domains. Some of the most common findings are deficits in motor control. However, to date no neuroimaging studies have evaluated basic motor control in HIV-infected patients using a multimodal approach. In this study, we utilized high-resolution structural imaging and task-state functional magnetic resonance imaging (fMRI) to assess brain structure and motor function in a homogeneous cohort of HIV-infected patients. We found that HIV-infected patients had significantly reduced gray matter (GM) volume in cortical regions, which are involved in motor control, including the bilateral posterior insula cortex, premotor cortex, and supramarginal gyrus. Increased activation in bilateral posterior insula cortices was also demonstrated by patients during hand movement tasks compared with healthy controls. More importantly, the reduced GM in bilateral posterior insula cortices was spatially coincident with abnormal brain activation in HIV-infected patients. In addition, the results of partial correlation analysis indicated that GM reduction in bilateral posterior insula cortices and premotor cortices was significantly correlated with immune system deterioration. This study is the first to demonstrate spatially coincident GM reduction and abnormal activation during motor performance in HIV-infected patients. Although it remains unknown whether the brain deficits can be recovered, our findings may yield new insights into neurologic injury underlying motor dysfunction in HAND. (orig.)

  1. Motor control is decision-making.

    Science.gov (United States)

    Wolpert, Daniel M; Landy, Michael S

    2012-12-01

    Motor behavior may be viewed as a problem of maximizing the utility of movement outcome in the face of sensory, motor and task uncertainty. Viewed in this way, and allowing for the availability of prior knowledge in the form of a probability distribution over possible states of the world, the choice of a movement plan and strategy for motor control becomes an application of statistical decision theory. This point of view has proven successful in recent years in accounting for movement under risk, inferring the loss function used in motor tasks, and explaining motor behavior in a wide variety of circumstances. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Altered resting-state effective connectivity of fronto-parietal motor control systems on the primary motor network following stroke

    Science.gov (United States)

    Inman, Cory S.; James, G. Andrew; Hamann, Stephan; Rajendra, Justin K.; Pagnoni, Giuseppe; Butler, Andrew J.

    2011-01-01

    Previous brain imaging work suggests that stroke alters the effective connectivity (the influence neural regions exert upon each other) of motor execution networks. The present study examines the intrinsic effective connectivity of top-down motor control in stroke survivors (n=13) relative to healthy participants (n=12). Stroke survivors exhibited significant deficits in motor function, as assessed by the Fugl-Meyer Motor Assessment. We used structural equation modeling (SEM) of resting-state fMRI data to investigate the relationship between motor deficits and the intrinsic effective connectivity between brain regions involved in motor control and motor execution. An exploratory adaptation of SEM determined the optimal model of motor execution effective connectivity in healthy participants, and confirmatory SEM assessed stroke survivors’ fit to that model. We observed alterations in spontaneous resting-state effective connectivity from fronto-parietal guidance systems to the motor network in stroke survivors. More specifically, diminished connectivity was found in connections from the superior parietal cortex to primary motor cortex and supplementary motor cortex. Furthermore, the paths demonstrated large individual variance in stroke survivors but less variance in healthy participants. These findings suggest that characterizing the deficits in resting-state connectivity of top-down processes in stroke survivors may help optimize cognitive and physical rehabilitation therapies by individually targeting specific neural pathway. PMID:21839174

  3. Control of octopus arm extension by a peripheral motor program.

    Science.gov (United States)

    Sumbre, G; Gutfreund, Y; Fiorito, G; Flash, T; Hochner, B

    2001-09-07

    For goal-directed arm movements, the nervous system generates a sequence of motor commands that bring the arm toward the target. Control of the octopus arm is especially complex because the arm can be moved in any direction, with a virtually infinite number of degrees of freedom. Here we show that arm extensions can be evoked mechanically or electrically in arms whose connection with the brain has been severed. These extensions show kinematic features that are almost identical to normal behavior, suggesting that the basic motor program for voluntary movement is embedded within the neural circuitry of the arm itself. Such peripheral motor programs represent considerable simplification in the motor control of this highly redundant appendage.

  4. Linear Parameter Varying Control of Induction Motors

    DEFF Research Database (Denmark)

    Trangbæk, Klaus

    The subject of this thesis is the development of linear parameter varying (LPV) controllers and observers for control of induction motors. The induction motor is one of the most common machines in industrial applications. Being a highly nonlinear system, it poses challenging control problems...... for high performance applications. This thesis demonstrates how LPV control theory provides a systematic way to achieve good performance for these problems. The main contributions of this thesis are the application of the LPV control theory to induction motor control as well as various contributions...

  5. Controller for computer control of brushless dc motors. [automobile engines

    Science.gov (United States)

    Hieda, L. S. (Inventor)

    1981-01-01

    A motor speed and torque controller for brushless d.c. motors provides an unusually smooth torque control arrangement. The controller provides a means for controlling a current waveform in each winding of a brushless dc motor by synchronization of an excitation pulse train from a programmable oscillator. Sensing of torque for synchronization is provided by a light beam chopper mounted on the motor rotor shaft. Speed and duty cycle are independently controlled by controlling the frequency and pulse width output of the programmable oscillator. A means is also provided so that current transitions from one motor winding to another is effected without abrupt changes in output torque.

  6. Illusory movement perception improves motor control for prosthetic hands

    Science.gov (United States)

    Marasco, Paul D.; Hebert, Jacqueline S.; Sensinger, Jon W.; Shell, Courtney E.; Schofield, Jonathon S.; Thumser, Zachary C.; Nataraj, Raviraj; Beckler, Dylan T.; Dawson, Michael R.; Blustein, Dan H.; Gill, Satinder; Mensh, Brett D.; Granja-Vazquez, Rafael; Newcomb, Madeline D.; Carey, Jason P.; Orzell, Beth M.

    2018-01-01

    To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement’s progress. This largely non-conscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. Here we report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. PMID:29540617

  7. Motor Control Research Requires Nonlinear Dynamics

    Science.gov (United States)

    Guastello, Stephen J.

    2006-01-01

    The author comments on the original article "The Cinderella of psychology: The neglect of motor control in the science of mental life and behavior," by D. A. Rosenbaum. Rosenbaum draws attention to the study of motor control and evaluates seven possible explanations for why the topic has been relatively neglected. The point of this comment is that…

  8. Advanced dc-Traction-Motor Control System

    Science.gov (United States)

    Vittone, O.

    1985-01-01

    Motor-control concept for battery-powered vehicles includes stateof-the-art power-transistor switching and separate excitation of motor windings in traction and regenerative braking. Switching transistors and other components of power-conditioning subsystem operate under control of computer that coordinates traction, braking, and protective functions.

  9. Timing and motor control in drumming

    DEFF Research Database (Denmark)

    Dahl, Sofia; Grossbach, Michael; Altenmüller, Eckart

    the stick movement becomes increasingly difficult, sometimes resulting in irregularities in timing and/or striking force. Timing irregularities can also be a revealing sign of motor control problems, such as focal dystonia (Jabusch, Vauth & Altenmüller, 2004). The "breakdown" in motor control can therefore...

  10. Fuzzy control of small servo motors

    Science.gov (United States)

    Maor, Ron; Jani, Yashvant

    1993-01-01

    To explore the benefits of fuzzy logic and understand the differences between the classical control methods and fuzzy control methods, the Togai InfraLogic applications engineering staff developed and implemented a motor control system for small servo motors. The motor assembly for testing the fuzzy and conventional controllers consist of servo motor RA13M and an encoder with a range of 4096 counts. An interface card was designed and fabricated to interface the motor assembly and encoder to an IBM PC. The fuzzy logic based motor controller was developed using the TILShell and Fuzzy C Development System on an IBM PC. A Proportional-Derivative (PD) type conventional controller was also developed and implemented in the IBM PC to compare the performance with the fuzzy controller. Test cases were defined to include step inputs of 90 and 180 degrees rotation, sine and square wave profiles in 5 to 20 hertz frequency range, as well as ramp inputs. In this paper we describe our approach to develop a fuzzy as well as PH controller, provide details of hardware set-up and test cases, and discuss the performance results. In comparison, the fuzzy logic based controller handles the non-linearities of the motor assembly very well and provides excellent control over a broad range of parameters. Fuzzy technology, as indicated by our results, possesses inherent adaptive features.

  11. Functional MRI in human motor control studies and clinical applications

    International Nuclear Information System (INIS)

    Toma, Keiichiro

    2002-01-01

    Functional magnetic resonance imaging (fMRI) has been a useful tool for the noninvasive mapping of brain function associated with various motor and cognitive tasks. Because fMRI is based on the blood oxygenation level dependent (BOLD) effect, it does not directly record neural activity. With the fMRI technique, distinguishing BOLD signals creased by cortical projection neurons from those created by intracortical neurons appears to be difficult. Two major experimental designs are used in fMRI studies: block designs and event-related designs. Block-designed fMRI presupposes the steady state of regional cerebral blood flow and has been applied to examinations of brain activation caused by tasks requiring sustained or repetitive movements. By contrast, the more recently developed event-related fMRI with time resolution of a few seconds allows the mapping of brain activation associated with a single movement according to the transient aspects of the hemodynamic response. Increasing evidence suggests that multiple motor areas are engaged in a networked manner to execute various motor acts. In order to understand functional brain maps, it is important that one understands sequential and parallel organizations of anatomical connections between multiple motor areas. In fMRI studies of complex motor tasks, elementary parameters such as movement length, force, velocity, acceleration and frequency should be controlled, because inconsistency in those parameters may alter the extent and intensity of motor cortical activation, confounding interpretation of the findings obtained. In addition to initiation of movements, termination of movements plays an important role in the successful achievement of complex movements. Brain areas exclusively related to the termination of movements have been, for the first time, uncovered with an event-related fMRI technique. We propose the application of fMRI to the elucidation of the pathophysiology of movement disorders, particularly dystonia

  12. Functional MRI in human motor control studies and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Toma, Keiichiro [Kyoto Univ. (Japan). Graduate School of Medicine; Nakai, Toshiharu [Inst. of Biomedical Research and Innovation, Kobe (Japan)

    2002-07-01

    Functional magnetic resonance imaging (fMRI) has been a useful tool for the noninvasive mapping of brain function associated with various motor and cognitive tasks. Because fMRI is based on the blood oxygenation level dependent (BOLD) effect, it does not directly record neural activity. With the fMRI technique, distinguishing BOLD signals creased by cortical projection neurons from those created by intracortical neurons appears to be difficult. Two major experimental designs are used in fMRI studies: block designs and event-related designs. Block-designed fMRI presupposes the steady state of regional cerebral blood flow and has been applied to examinations of brain activation caused by tasks requiring sustained or repetitive movements. By contrast, the more recently developed event-related fMRI with time resolution of a few seconds allows the mapping of brain activation associated with a single movement according to the transient aspects of the hemodynamic response. Increasing evidence suggests that multiple motor areas are engaged in a networked manner to execute various motor acts. In order to understand functional brain maps, it is important that one understands sequential and parallel organizations of anatomical connections between multiple motor areas. In fMRI studies of complex motor tasks, elementary parameters such as movement length, force, velocity, acceleration and frequency should be controlled, because inconsistency in those parameters may alter the extent and intensity of motor cortical activation, confounding interpretation of the findings obtained. In addition to initiation of movements, termination of movements plays an important role in the successful achievement of complex movements. Brain areas exclusively related to the termination of movements have been, for the first time, uncovered with an event-related fMRI technique. We propose the application of fMRI to the elucidation of the pathophysiology of movement disorders, particularly dystonia

  13. Birth of projection neurons in adult avian brain may be related to perceptual or motor learning

    International Nuclear Information System (INIS)

    Alvarez-Buylla, A.; Kirn, J.R.; Nottebohm, F.

    1990-01-01

    Projection neurons that form part of the motor pathway for song control continue to be produced and to replace older projection neurons in adult canaries and zebra finches. This is shown by combining [3H]thymidine, a cell birth marker, and fluorogold, a retrogradely transported tracer of neuronal connectivity. Species and seasonal comparisons suggest that this process is related to the acquisition of perceptual or motor memories. The ability of an adult brain to produce and replace projection neurons should influence our thinking on brain repair

  14. Functional near infrared spectroscopy of the sensory and motor brain regions with simultaneous kinematic and EMG monitoring during motor tasks

    OpenAIRE

    Sukal-Moulton, Theresa; de Campos, Ana Carolina; Stanley, Christopher J; Damiano, Diane L

    2014-01-01

    There are several advantages that functional near-infrared spectroscopy (fNIRS) presents in the study of the neural control of human movement. It is relatively flexible with respect to participant positioning and allows for some head movements during tasks. Additionally, it is inexpensive, light weight, and portable, with very few contraindications to its use. This presents a unique opportunity to study functional brain activity during motor tasks in individuals who are typically developing, ...

  15. Representational Similarity Analysis Reveals Heterogeneous Networks Supporting Speech Motor Control

    DEFF Research Database (Denmark)

    Zheng, Zane; Cusack, Rhodri; Johnsrude, Ingrid

    The everyday act of speaking involves the complex processes of speech motor control. One important feature of such control is regulation of articulation when auditory concomitants of speech do not correspond to the intended motor gesture. While theoretical accounts of speech monitoring posit...... multiple functional components required for detection of errors in speech planning (e.g., Levelt, 1983), neuroimaging studies generally indicate either single brain regions sensitive to speech production errors, or small, discrete networks. Here we demonstrate that the complex system controlling speech...... is supported by a complex neural network that is involved in linguistic, motoric and sensory processing. With the aid of novel real-time acoustic analyses and representational similarity analyses of fMRI signals, our data show functionally differentiated networks underlying auditory feedback control of speech....

  16. Speed controller for an alternating - current motor

    International Nuclear Information System (INIS)

    Bolie, V.W.

    1984-01-01

    A controller for a multi-phase ac motor that is subject to a large inertial load, e.g. an induction motor driving a heavy spinning rotor of a neutron chopper that must be rotated in phase-locked synchronism with a reference pulse train that is representative of an ac power supply signal Esub(L) having a meandering line frequency, includes a sensor which provides a feedback pulse train representative of the actual speed of the motor which is compared (by counting clock pulses between feedback pulses) with a reference clock signal in a computing unit to provide a motor control signal Esub(c). The motor control signal is a weighted linear sum of a speed error signal, a phase error signal, and a drift error signal, the magnitudes of which are recalculated and updated with each revolution of the motor shaft. The speed error signal is constant for large speed errors but highly sensitive to small speed errors. The stator windings of the motor are driven by variable-frequency power amplifiers which are controlled by the motor control signal Esub(c) via PROMs which store digital representations of sine and cosine waveforms in quadrature. (author)

  17. Neuromechanics: an integrative approach for understanding motor control.

    Science.gov (United States)

    Nishikawa, Kiisa; Biewener, Andrew A; Aerts, Peter; Ahn, Anna N; Chiel, Hillel J; Daley, Monica A; Daniel, Thomas L; Full, Robert J; Hale, Melina E; Hedrick, Tyson L; Lappin, A Kristopher; Nichols, T Richard; Quinn, Roger D; Satterlie, Richard A; Szymik, Brett

    2007-07-01

    Neuromechanics seeks to understand how muscles, sense organs, motor pattern generators, and brain interact to produce coordinated movement, not only in complex terrain but also when confronted with unexpected perturbations. Applications of neuromechanics include ameliorating human health problems (including prosthesis design and restoration of movement following brain or spinal cord injury), as well as the design, actuation and control of mobile robots. In animals, coordinated movement emerges from the interplay among descending output from the central nervous system, sensory input from body and environment, muscle dynamics, and the emergent dynamics of the whole animal. The inevitable coupling between neural information processing and the emergent mechanical behavior of animals is a central theme of neuromechanics. Fundamentally, motor control involves a series of transformations of information, from brain and spinal cord to muscles to body, and back to brain. The control problem revolves around the specific transfer functions that describe each transformation. The transfer functions depend on the rules of organization and operation that determine the dynamic behavior of each subsystem (i.e., central processing, force generation, emergent dynamics, and sensory processing). In this review, we (1) consider the contributions of muscles, (2) sensory processing, and (3) central networks to motor control, (4) provide examples to illustrate the interplay among brain, muscles, sense organs and the environment in the control of movement, and (5) describe advances in both robotics and neuromechanics that have emerged from application of biological principles in robotic design. Taken together, these studies demonstrate that (1) intrinsic properties of muscle contribute to dynamic stability and control of movement, particularly immediately after perturbations; (2) proprioceptive feedback reinforces these intrinsic self-stabilizing properties of muscle; (3) control systems

  18. Oscillation control system for electric motor drive

    Science.gov (United States)

    Slicker, J.M.; Sereshteh, A.

    1988-08-30

    A feedback system for controlling mechanical oscillations in the torsionally complaint drive train of an electric or other vehicle. Motor speed is converted in a processor to estimate state signals in which a plant model which are used to electronically modify the torque commands applied to the motor. 5 figs.

  19. Computerized Torque Control for Large dc Motors

    Science.gov (United States)

    Willett, Richard M.; Carroll, Michael J.; Geiger, Ronald V.

    1987-01-01

    Speed and torque ranges in generator mode extended. System of shunt resistors, electronic switches, and pulse-width modulation controls torque exerted by large, three-phase, electronically commutated dc motor. Particularly useful for motor operating in generator mode because it extends operating range to low torque and high speed.

  20. DC motor speed control using fuzzy logic controller

    Science.gov (United States)

    Ismail, N. L.; Zakaria, K. A.; Nazar, N. S. Moh; Syaripuddin, M.; Mokhtar, A. S. N.; Thanakodi, S.

    2018-02-01

    The automatic control has played a vital role in the advance of engineering and science. Nowadays in industries, the control of direct current (DC) motor is a common practice thus the implementation of DC motor controller speed is important. The main purpose of motor speed control is to keep the rotation of the motor at the present speed and to drive a system at the demand speed. The main purpose of this project is to control speed of DC Series Wound Motor using Fuzzy Logic Controller (FLC). The expectation of this project is the Fuzzy Logic Controller will get the best performance compared to dc motor without controller in terms of settling time (Ts), rise time (Tr), peak time (Tp) and percent overshoot (%OS).

  1. Clinical studies of brain functional images by motor activation using single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kawaguchi, Masahiro [Gifu Univ. (Japan). School of Medicine

    1998-09-01

    Thirty participants (10 normal controls; group A, 5 patients with brain tumors located near central sulcus without hemiparesis; group B, 10 patients with brain tumors located near central sulcus with hemiparesis; group C, and 5 patients with brain tumors besides the central regions with hemiparesis; group D) were enrolled. The images were performed by means of split-dose method with {sup 99m}Tc-ECD at rest condition (SPECT 1) and during hand grasping (SPECT 2). The activation SPECT were obtained by subtracting SPECT 1 from SPECT 2, and the functional mapping was made by the strict registration of the activation SPECT with 3D MRI. To evaluate the changes of CBF (%{Delta}CBF) of the sensorimotor and supplementary motor areas on the functional mapping, ratio of the average counts of SPECT 1 and SPECT 2 was calculated and statistically compared. The functional activation paradigms caused a significant increase of CBF in the sensorimotor area contra-lateral to the stimulated hand, although the sensorimotor area and the central sulcus in groups B and C were dislocated, compared with hemisphere of non-tumor side. The sensorimotor area ipsi-lateral to the stimulated hand could be detected in almost of all subjects. The supplementary motor area could be detected in all subjects. In group A, the average %{Delta}CBF were up 24.1{+-}4.3% in the contra-lateral sensorimotor area, and 22.3{+-}3.6% in the supplementary motor area, respectively. The average %{Delta}CBF in the contra-lateral sensorimotor area of group D was significantly higher than that of group A. The brain functional mapping by motor activation using SPECT could localize the area of cortical motor function in normal volunteers and patients with brain tumors. The changes of regional CBF by activation SPECT precisely assess the cortical motor function even in patients with brain tumors located near central sulcus. (K.H.)

  2. Clinical studies of brain functional images by motor activation using single photon emission computed tomography

    International Nuclear Information System (INIS)

    Kawaguchi, Masahiro

    1998-01-01

    Thirty participants (10 normal controls; group A, 5 patients with brain tumors located near central sulcus without hemiparesis; group B, 10 patients with brain tumors located near central sulcus with hemiparesis; group C, and 5 patients with brain tumors besides the central regions with hemiparesis; group D) were enrolled. The images were performed by means of split-dose method with 99m Tc-ECD at rest condition (SPECT 1) and during hand grasping (SPECT 2). The activation SPECT were obtained by subtracting SPECT 1 from SPECT 2, and the functional mapping was made by the strict registration of the activation SPECT with 3D MRI. To evaluate the changes of CBF (%ΔCBF) of the sensorimotor and supplementary motor areas on the functional mapping, ratio of the average counts of SPECT 1 and SPECT 2 was calculated and statistically compared. The functional activation paradigms caused a significant increase of CBF in the sensorimotor area contra-lateral to the stimulated hand, although the sensorimotor area and the central sulcus in groups B and C were dislocated, compared with hemisphere of non-tumor side. The sensorimotor area ipsi-lateral to the stimulated hand could be detected in almost of all subjects. The supplementary motor area could be detected in all subjects. In group A, the average %ΔCBF were up 24.1±4.3% in the contra-lateral sensorimotor area, and 22.3±3.6% in the supplementary motor area, respectively. The average %ΔCBF in the contra-lateral sensorimotor area of group D was significantly higher than that of group A. The brain functional mapping by motor activation using SPECT could localize the area of cortical motor function in normal volunteers and patients with brain tumors. The changes of regional CBF by activation SPECT precisely assess the cortical motor function even in patients with brain tumors located near central sulcus. (K.H.)

  3. Association Between Motor Symptoms and Brain Metabolism in Early Huntington Disease.

    Science.gov (United States)

    Gaura, Véronique; Lavisse, Sonia; Payoux, Pierre; Goldman, Serge; Verny, Christophe; Krystkowiak, Pierre; Damier, Philippe; Supiot, Frédéric; Bachoud-Levi, Anne-Catherine; Remy, Philippe

    2017-09-01

    Brain hypometabolism is associated with the clinical consequences of the degenerative process, but little is known about regional hypermetabolism, sometimes observed in the brain of patients with clinically manifest Huntington disease (HD). Studying the role of regional hypermetabolism is needed to better understand its interaction with the motor symptoms of the disease. To investigate the association between brain hypometabolism and hypermetabolism with motor scores of patients with early HD. This study started in 2001, and analysis was completed in 2016. Sixty symptomatic patients with HD and 15 healthy age-matched control individuals underwent positron emission tomography to measure cerebral metabolism in this cross-sectional study. They also underwent the Unified Huntington's Disease Rating Scale motor test, and 2 subscores were extracted: (1) a hyperkinetic score, combining dystonia and chorea, and (2) a hypokinetic score, combining bradykinesia and rigidity. Statistical parametric mapping software (SPM5) was used to identify all hypo- and hypermetabolic regions in patients with HD relative to control individuals. Correlation analyses (P motor subscores and brain metabolic values were performed for regions with significant hypometabolism and hypermetabolism. Among 60 patients with HD, 22 were women (36.7%), and the mean (SD) age was 44.6 (7.6) years. Of the 15 control individuals, 7 were women (46.7%), and the mean (SD) age was 42.2 (7.3) years. In statistical parametric mapping, striatal hypometabolism was significantly correlated with the severity of all motor scores. Hypermetabolism was negatively correlated only with hypokinetic scores in the cuneus (z score = 3.95, P motor scores were associated with higher metabolic values in the inferior parietal lobule, anterior cingulate, inferior temporal lobule, the dentate nucleus, and the cerebellar lobules IV/V, VI, and VIII bilaterally corresponding to the motor regions of the cerebellum (z score = 3

  4. Effect of 3G cell phone exposure with computer controlled 2-D stepper motor on non-thermal activation of the hsp27/p38MAPK stress pathway in rat brain.

    Science.gov (United States)

    Kesari, Kavindra Kumar; Meena, Ramovatar; Nirala, Jayprakash; Kumar, Jitender; Verma, H N

    2014-03-01

    Cell phone radiation exposure and its biological interaction is the present concern of debate. Present study aimed to investigate the effect of 3G cell phone exposure with computer controlled 2-D stepper motor on 45-day-old male Wistar rat brain. Animals were exposed for 2 h a day for 60 days by using mobile phone with angular movement up to zero to 30°. The variation of the motor is restricted to 90° with respect to the horizontal plane, moving at a pre-determined rate of 2° per minute. Immediately after 60 days of exposure, animals were scarified and numbers of parameters (DNA double-strand break, micronuclei, caspase 3, apoptosis, DNA fragmentation, expression of stress-responsive genes) were performed. Result shows that microwave radiation emitted from 3G mobile phone significantly induced DNA strand breaks in brain. Meanwhile a significant increase in micronuclei, caspase 3 and apoptosis were also observed in exposed group (P 3G mobile phone exposure causes a transient increase in phosphorylation of hsp27, hsp70, and p38 mitogen-activated protein kinase (p38MAPK), which leads to mitochondrial dysfunction-mediated cytochrome c release and subsequent activation of caspases, involved in the process of radiation-induced apoptotic cell death. Study shows that the oxidative stress is the main factor which activates a variety of cellular signal transduction pathways, among them the hsp27/p38MAPK is the pathway of principle stress response. Results conclude that 3G mobile phone radiations affect the brain function and cause several neurological disorders.

  5. Brain Plasticity and Motor Practice in Cognitive Aging

    Directory of Open Access Journals (Sweden)

    Liuyang eCai

    2014-03-01

    Full Text Available For more than two decades, there have been extensive studies of experience-based neural plasticity exploring effective applications of brain plasticity for cognitive and motor development. Research suggests that human brains continuously undergo structural reorganization and functional changes in response to stimulations or training. From a developmental point of view, the assumption of lifespan brain plasticity has been extended to older adults in terms of the benefits of cognitive training and physical therapy. To summarize recent developments, first, we introduce the concept of neural plasticity from a developmental perspective. Secondly, we note that motor learning often refers to deliberate practice and the resulting performance enhancement and adaptability. We discuss the close interplay between neural plasticity, motor learning and cognitive aging. Thirdly, we review research on motor skill acquisition in older adults with, and without, impairments relative to aging-related cognitive decline. Finally, to enhance future research and application, we highlight the implications of neural plasticity in skills learning and cognitive rehabilitation for the aging population.

  6. Sensorimotor rhythm-based brain-computer interface training: the impact on motor cortical responsiveness

    Science.gov (United States)

    Pichiorri, F.; De Vico Fallani, F.; Cincotti, F.; Babiloni, F.; Molinari, M.; Kleih, S. C.; Neuper, C.; Kübler, A.; Mattia, D.

    2011-04-01

    The main purpose of electroencephalography (EEG)-based brain-computer interface (BCI) technology is to provide an alternative channel to support communication and control when motor pathways are interrupted. Despite the considerable amount of research focused on the improvement of EEG signal detection and translation into output commands, little is known about how learning to operate a BCI device may affect brain plasticity. This study investigated if and how sensorimotor rhythm-based BCI training would induce persistent functional changes in motor cortex, as assessed with transcranial magnetic stimulation (TMS) and high-density EEG. Motor imagery (MI)-based BCI training in naïve participants led to a significant increase in motor cortical excitability, as revealed by post-training TMS mapping of the hand muscle's cortical representation; peak amplitude and volume of the motor evoked potentials recorded from the opponens pollicis muscle were significantly higher only in those subjects who develop a MI strategy based on imagination of hand grasping to successfully control a computer cursor. Furthermore, analysis of the functional brain networks constructed using a connectivity matrix between scalp electrodes revealed a significant decrease in the global efficiency index for the higher-beta frequency range (22-29 Hz), indicating that the brain network changes its topology with practice of hand grasping MI. Our findings build the neurophysiological basis for the use of non-invasive BCI technology for monitoring and guidance of motor imagery-dependent brain plasticity and thus may render BCI a viable tool for post-stroke rehabilitation.

  7. Brain-to-brain hyperclassification reveals action-specific motor mapping of observed actions in humans.

    Science.gov (United States)

    Smirnov, Dmitry; Lachat, Fanny; Peltola, Tomi; Lahnakoski, Juha M; Koistinen, Olli-Pekka; Glerean, Enrico; Vehtari, Aki; Hari, Riitta; Sams, Mikko; Nummenmaa, Lauri

    2017-01-01

    Seeing an action may activate the corresponding action motor code in the observer. It remains unresolved whether seeing and performing an action activates similar action-specific motor codes in the observer and the actor. We used novel hyperclassification approach to reveal shared brain activation signatures of action execution and observation in interacting human subjects. In the first experiment, two "actors" performed four types of hand actions while their haemodynamic brain activations were measured with 3-T functional magnetic resonance imaging (fMRI). The actions were videotaped and shown to 15 "observers" during a second fMRI experiment. Eleven observers saw the videos of one actor, and the remaining four observers saw the videos of the other actor. In a control fMRI experiment, one of the actors performed actions with closed eyes, and five new observers viewed these actions. Bayesian canonical correlation analysis was applied to functionally realign observers' and actors' fMRI data. Hyperclassification of the seen actions was performed with Bayesian logistic regression trained on actors' data and tested with observers' data. Without the functional realignment, between-subjects accuracy was at chance level. With the realignment, the accuracy increased on average by 15 percentage points, exceeding both the chance level and the accuracy without functional realignment. The highest accuracies were observed in occipital, parietal and premotor cortices. Hyperclassification exceeded chance level also when the actor did not see her own actions. We conclude that the functional brain activation signatures underlying action execution and observation are partly shared, yet these activation signatures may be anatomically misaligned across individuals.

  8. Motor network plasticity and low-frequency oscillations abnormalities in patients with brain gliomas: a functional MRI study.

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    Chen Niu

    Full Text Available Brain plasticity is often associated with the process of slow-growing tumor formation, which remodels neural organization and optimizes brain network function. In this study, we aimed to investigate whether motor function plasticity would display deficits in patients with slow-growing brain tumors located in or near motor areas, but who were without motor neurological deficits. We used resting-state functional magnetic resonance imaging to probe motor networks in 15 patients with histopathologically confirmed brain gliomas and 15 age-matched healthy controls. All subjects performed a motor task to help identify individual motor activity in the bilateral primary motor cortex (PMC and supplementary motor area (SMA. Frequency-based analysis at three different frequencies was then used to investigate possible alterations in the power spectral density (PSD of low-frequency oscillations. For each group, the average PSD was determined for each brain region and a nonparametric test was performed to determine the difference in power between the two groups. Significantly reduced inter-hemispheric functional connectivity between the left and right PMC was observed in patients compared with controls (P<0.05. We also found significantly decreased PSD in patients compared to that in controls, in all three frequency bands (low: 0.01-0.02 Hz; middle: 0.02-0.06 Hz; and high: 0.06-0.1 Hz, at three key motor regions. These findings suggest that in asymptomatic patients with brain tumors located in eloquent regions, inter-hemispheric connection may be more vulnerable. A comparison of the two approaches indicated that power spectral analysis is more sensitive than functional connectivity analysis for identifying the neurological abnormalities underlying motor function plasticity induced by slow-growing tumors.

  9. Theories and control models and motor learning: clinical applications in neuro-rehabilitation.

    Science.gov (United States)

    Cano-de-la-Cuerda, R; Molero-Sánchez, A; Carratalá-Tejada, M; Alguacil-Diego, I M; Molina-Rueda, F; Miangolarra-Page, J C; Torricelli, D

    2015-01-01

    In recent decades there has been a special interest in theories that could explain the regulation of motor control, and their applications. These theories are often based on models of brain function, philosophically reflecting different criteria on how movement is controlled by the brain, each being emphasised in different neural components of the movement. The concept of motor learning, regarded as the set of internal processes associated with practice and experience that produce relatively permanent changes in the ability to produce motor activities through a specific skill, is also relevant in the context of neuroscience. Thus, both motor control and learning are seen as key fields of study for health professionals in the field of neuro-rehabilitation. The major theories of motor control are described, which include, motor programming theory, systems theory, the theory of dynamic action, and the theory of parallel distributed processing, as well as the factors that influence motor learning and its applications in neuro-rehabilitation. At present there is no consensus on which theory or model defines the regulations to explain motor control. Theories of motor learning should be the basis for motor rehabilitation. The new research should apply the knowledge generated in the fields of control and motor learning in neuro-rehabilitation. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  10. Motor imagery based brain-computer interfaces: An emerging technology to rehabilitate motor deficits.

    Science.gov (United States)

    Alonso-Valerdi, Luz Maria; Salido-Ruiz, Ricardo Antonio; Ramirez-Mendoza, Ricardo A

    2015-12-01

    When the sensory-motor integration system is malfunctioning provokes a wide variety of neurological disorders, which in many cases cannot be treated with conventional medication, or via existing therapeutic technology. A brain-computer interface (BCI) is a tool that permits to reintegrate the sensory-motor loop, accessing directly to brain information. A potential, promising and quite investigated application of BCI has been in the motor rehabilitation field. It is well-known that motor deficits are the major disability wherewith the worldwide population lives. Therefore, this paper aims to specify the foundation of motor rehabilitation BCIs, as well as to review the recent research conducted so far (specifically, from 2007 to date), in order to evaluate the suitability and reliability of this technology. Although BCI for post-stroke rehabilitation is still in its infancy, the tendency is towards the development of implantable devices that encompass a BCI module plus a stimulation system. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Two Archetypes of Motor Control Research.

    Science.gov (United States)

    Latash, Mark L

    2010-07-01

    This reply to the Commentaries is focused on two archetypes of motor control research, one based on physics and physiology and the other based on control theory and ideas of neural computations. The former approach, represented by the equilibrium-point hypothesis, strives to discover the physical laws and salient physiological variables that make purposeful coordinated movements possible. The latter approach, represented by the ideas of internal models and optimal control, tries to apply methods of control developed for man-made inanimate systems to the human body. Specific issues related to control with subthreshold membrane depolarization, motor redundancy, and the idea of synergies are briefly discussed.

  12. Motor control by precisely timed spike patterns

    DEFF Research Database (Denmark)

    Srivastava, Kyle H; Holmes, Caroline M; Vellema, Michiel

    2017-01-01

    whether the information in spike timing actually plays a role in brain function. By examining the activity of individual motor units (the muscle fibers innervated by a single motor neuron) and manipulating patterns of activation of these neurons, we provide both correlative and causal evidence......A fundamental problem in neuroscience is understanding how sequences of action potentials ("spikes") encode information about sensory signals and motor outputs. Although traditional theories assume that this information is conveyed by the total number of spikes fired within a specified time...... interval (spike rate), recent studies have shown that additional information is carried by the millisecond-scale timing patterns of action potentials (spike timing). However, it is unknown whether or how subtle differences in spike timing drive differences in perception or behavior, leaving it unclear...

  13. Brain-wide neuronal dynamics during motor adaptation in zebrafish.

    Science.gov (United States)

    Ahrens, Misha B; Li, Jennifer M; Orger, Michael B; Robson, Drew N; Schier, Alexander F; Engert, Florian; Portugues, Ruben

    2012-05-09

    A fundamental question in neuroscience is how entire neural circuits generate behaviour and adapt it to changes in sensory feedback. Here we use two-photon calcium imaging to record the activity of large populations of neurons at the cellular level, throughout the brain of larval zebrafish expressing a genetically encoded calcium sensor, while the paralysed animals interact fictively with a virtual environment and rapidly adapt their motor output to changes in visual feedback. We decompose the network dynamics involved in adaptive locomotion into four types of neuronal response properties, and provide anatomical maps of the corresponding sites. A subset of these signals occurred during behavioural adjustments and are candidates for the functional elements that drive motor learning. Lesions to the inferior olive indicate a specific functional role for olivocerebellar circuitry in adaptive locomotion. This study enables the analysis of brain-wide dynamics at single-cell resolution during behaviour.

  14. Backstepping Strategy for Induction Motor Control

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Vadstrup, P.; Børsting, H.

    2000-01-01

    Using backstepping, which is a recursive nonlinear design method, a novel approach to control of induction motors is developed. The resulting scheme leads to a nonlinear controller for the torque and the amplitude of the field. A combination of nonlinear damping and observer backstepping with a s......Using backstepping, which is a recursive nonlinear design method, a novel approach to control of induction motors is developed. The resulting scheme leads to a nonlinear controller for the torque and the amplitude of the field. A combination of nonlinear damping and observer backstepping...... with a simple flux observer is used in the design. Assuming known motor parameters the design achieves stability with guaranteed region of attraction. It is also shown how a conventional field oriented controller may be obtained by omitting parts of the nonlinear controller....

  15. FUZZY LOGIC CONTROL OF ELECTRIC MOTORS AND MOTOR DRIVES: FEASIBILITY STUDY

    Science.gov (United States)

    The report gives results of a study (part 1) of fuzzy logic motor control (FLMC). The study included: 1) reviews of existing applications of fuzzy logic, of motor operation, and of motor control; 2) a description of motor control schemes that can utilize FLMC; 3) selection of a m...

  16. Complex Regional Pain Syndrome Type I Affects Brain Structure in Prefrontal and Motor Cortex

    Science.gov (United States)

    Pleger, Burkhard; Draganski, Bogdan; Schwenkreis, Peter; Lenz, Melanie; Nicolas, Volkmar; Maier, Christoph; Tegenthoff, Martin

    2014-01-01

    The complex regional pain syndrome (CRPS) is a rare but debilitating pain disorder that mostly occurs after injuries to the upper limb. A number of studies indicated altered brain function in CRPS, whereas possible influences on brain structure remain poorly investigated. We acquired structural magnetic resonance imaging data from CRPS type I patients and applied voxel-by-voxel statistics to compare white and gray matter brain segments of CRPS patients with matched controls. Patients and controls were statistically compared in two different ways: First, we applied a 2-sample ttest to compare whole brain white and gray matter structure between patients and controls. Second, we aimed to assess structural alterations specifically of the primary somatosensory (S1) and motor cortex (M1) contralateral to the CRPS affected side. To this end, MRI scans of patients with left-sided CRPS (and matched controls) were horizontally flipped before preprocessing and region-of-interest-based group comparison. The unpaired ttest of the “non-flipped” data revealed that CRPS patients presented increased gray matter density in the dorsomedial prefrontal cortex. The same test applied to the “flipped” data showed further increases in gray matter density, not in the S1, but in the M1 contralateral to the CRPS-affected limb which were inversely related to decreased white matter density of the internal capsule within the ipsilateral brain hemisphere. The gray-white matter interaction between motor cortex and internal capsule suggests compensatory mechanisms within the central motor system possibly due to motor dysfunction. Altered gray matter structure in dorsomedial prefrontal cortex may occur in response to emotional processes such as pain-related suffering or elevated analgesic top-down control. PMID:24416397

  17. Complex regional pain syndrome type I affects brain structure in prefrontal and motor cortex.

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    Burkhard Pleger

    Full Text Available The complex regional pain syndrome (CRPS is a rare but debilitating pain disorder that mostly occurs after injuries to the upper limb. A number of studies indicated altered brain function in CRPS, whereas possible influences on brain structure remain poorly investigated. We acquired structural magnetic resonance imaging data from CRPS type I patients and applied voxel-by-voxel statistics to compare white and gray matter brain segments of CRPS patients with matched controls. Patients and controls were statistically compared in two different ways: First, we applied a 2-sample ttest to compare whole brain white and gray matter structure between patients and controls. Second, we aimed to assess structural alterations specifically of the primary somatosensory (S1 and motor cortex (M1 contralateral to the CRPS affected side. To this end, MRI scans of patients with left-sided CRPS (and matched controls were horizontally flipped before preprocessing and region-of-interest-based group comparison. The unpaired ttest of the "non-flipped" data revealed that CRPS patients presented increased gray matter density in the dorsomedial prefrontal cortex. The same test applied to the "flipped" data showed further increases in gray matter density, not in the S1, but in the M1 contralateral to the CRPS-affected limb which were inversely related to decreased white matter density of the internal capsule within the ipsilateral brain hemisphere. The gray-white matter interaction between motor cortex and internal capsule suggests compensatory mechanisms within the central motor system possibly due to motor dysfunction. Altered gray matter structure in dorsomedial prefrontal cortex may occur in response to emotional processes such as pain-related suffering or elevated analgesic top-down control.

  18. BRAIN-COMPUTER-INTERFACE – SUPPORTED MOTOR IMAGERY TRAININTG FOR PATIENTS WITH HEMIPARESIS

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    O. A. Mokienko

    2013-01-01

    Full Text Available The aim of study was to assess the feasibility of motor imagery supported brain-computer interface in patients with hemiparesis. 13 patients with central paresis of the hand and 15 healthy volunteers were learning to control EEG-based interface with feedback. No differences on interface control quality were found between patients and healthy subjects. The trainings were accompanied by the desynchronization of sensorimotor rhythm. In patients with cortical damage the source of EEG-activity was dislocated.

  19. Effect of Error Augmentation on Brain Activation and Motor Learning of a Complex Locomotor Task

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    Laura Marchal-Crespo

    2017-09-01

    Full Text Available Up to date, the functional gains obtained after robot-aided gait rehabilitation training are limited. Error augmenting strategies have a great potential to enhance motor learning of simple motor tasks. However, little is known about the effect of these error modulating strategies on complex tasks, such as relearning to walk after a neurologic accident. Additionally, neuroimaging evaluation of brain regions involved in learning processes could provide valuable information on behavioral outcomes. We investigated the effect of robotic training strategies that augment errors—error amplification and random force disturbance—and training without perturbations on brain activation and motor learning of a complex locomotor task. Thirty-four healthy subjects performed the experiment with a robotic stepper (MARCOS in a 1.5 T MR scanner. The task consisted in tracking a Lissajous figure presented on a display by coordinating the legs in a gait-like movement pattern. Behavioral results showed that training without perturbations enhanced motor learning in initially less skilled subjects, while error amplification benefited better-skilled subjects. Training with error amplification, however, hampered transfer of learning. Randomly disturbing forces induced learning and promoted transfer in all subjects, probably because the unexpected forces increased subjects' attention. Functional MRI revealed main effects of training strategy and skill level during training. A main effect of training strategy was seen in brain regions typically associated with motor control and learning, such as, the basal ganglia, cerebellum, intraparietal sulcus, and angular gyrus. Especially, random disturbance and no perturbation lead to stronger brain activation in similar brain regions than error amplification. Skill-level related effects were observed in the IPS, in parts of the superior parietal lobe (SPL, i.e., precuneus, and temporal cortex. These neuroimaging findings

  20. Functional near infrared spectroscopy of the sensory and motor brain regions with simultaneous kinematic and EMG monitoring during motor tasks.

    Science.gov (United States)

    Sukal-Moulton, Theresa; de Campos, Ana Carolina; Stanley, Christopher J; Damiano, Diane L

    2014-12-05

    There are several advantages that functional near-infrared spectroscopy (fNIRS) presents in the study of the neural control of human movement. It is relatively flexible with respect to participant positioning and allows for some head movements during tasks. Additionally, it is inexpensive, light weight, and portable, with very few contraindications to its use. This presents a unique opportunity to study functional brain activity during motor tasks in individuals who are typically developing, as well as those with movement disorders, such as cerebral palsy. An additional consideration when studying movement disorders, however, is the quality of actual movements performed and the potential for additional, unintended movements. Therefore, concurrent monitoring of both blood flow changes in the brain and actual movements of the body during testing is required for appropriate interpretation of fNIRS results. Here, we show a protocol for the combination of fNIRS with muscle and kinematic monitoring during motor tasks. We explore gait, a unilateral multi-joint movement (cycling), and two unilateral single-joint movements (isolated ankle dorsiflexion, and isolated hand squeezing). The techniques presented can be useful in studying both typical and atypical motor control, and can be modified to investigate a broad range of tasks and scientific questions.

  1. Perinatal Development of the Motor Systems Involved in Postural Control

    Directory of Open Access Journals (Sweden)

    Laurent Vinay

    2005-01-01

    Full Text Available Motor behaviors of some species, such as the rat and the human baby, are quite immature at birth. Here we review recent data on some of the mechanisms underlying the postnatal maturation of posture in the rat, in particular the development of pathways descending from the brain stem and projecting onto the lumbar enlargement of the spinal cord. A short-lasting depletion in serotonin affects both posture and the excitability of motoneurons. Here we try to extrapolate to human development and suggest that the abnormalities in motor control observed in childhood—e.g, deficits in motor coordination—might have their roots in the prenatal period, in particular serotonin depletion due to exposure to several environmental and toxicological factors during pregnancy.

  2. Reduced NAA in motor and non-motor brain regions in amyotrophic lateral sclerosis: a cross-sectional and longitudinal study.

    Science.gov (United States)

    Rule, R R; Suhy, J; Schuff, N; Gelinas, D F; Miller, R G; Weiner, M W

    2004-09-01

    After replication of previous findings we aimed to: 1) determine if previously reported (1)H MRSI differences between ALS patients and control subjects are limited to the motor cortex; and 2) determine the longitudinal metabolic changes corresponding to varying levels of diagnostic certainty. Twenty-one patients with possible/suspected ALS, 24 patients with probable/definite ALS and 17 control subjects underwent multislice (1)H MRSI co-registered with tissue-segmented MRI to obtain concentrations of the brain metabolites N-acetylaspartate (NAA), creatine, and choline in the left and right motor cortex and in gray matter and white matter of non-motor regions in the brain. In the more affected hemisphere, reductions in the ratios, NAA/Cho and NAA/Cre+Cho were observed both within (12.6% and 9.5% respectively) and outside (9.2% and 7.3% respectively) the motor cortex in probable/definite ALS. However, these reductions were significantly greater within the motor cortex (PNAA/Cho and PNAA/Cre+Cho). Longitudinal changes in NAA were observed at three months within the motor cortex of both possible/suspected ALS patients (PNAA ratios are reduced in the motor cortex and outside the motor cortex in ALS, suggesting widespread neuronal injury. Longitudinal changes of NAA are not reliable, suggesting that NAA may not be a useful surrogate marker for treatment trials.

  3. Evolution of brain-computer interfaces: going beyond classic motor physiology

    Science.gov (United States)

    Leuthardt, Eric C.; Schalk, Gerwin; Roland, Jarod; Rouse, Adam; Moran, Daniel W.

    2010-01-01

    The notion that a computer can decode brain signals to infer the intentions of a human and then enact those intentions directly through a machine is becoming a realistic technical possibility. These types of devices are known as brain-computer interfaces (BCIs). The evolution of these neuroprosthetic technologies could have significant implications for patients with motor disabilities by enhancing their ability to interact and communicate with their environment. The cortical physiology most investigated and used for device control has been brain signals from the primary motor cortex. To date, this classic motor physiology has been an effective substrate for demonstrating the potential efficacy of BCI-based control. However, emerging research now stands to further enhance our understanding of the cortical physiology underpinning human intent and provide further signals for more complex brain-derived control. In this review, the authors report the current status of BCIs and detail the emerging research trends that stand to augment clinical applications in the future. PMID:19569892

  4. Motor priming in virtual reality can augment motor-imagery training efficacy in restorative brain-computer interaction: a within-subject analysis.

    Science.gov (United States)

    Vourvopoulos, Athanasios; Bermúdez I Badia, Sergi

    2016-08-09

    The use of Brain-Computer Interface (BCI) technology in neurorehabilitation provides new strategies to overcome stroke-related motor limitations. Recent studies demonstrated the brain's capacity for functional and structural plasticity through BCI. However, it is not fully clear how we can take full advantage of the neurobiological mechanisms underlying recovery and how to maximize restoration through BCI. In this study we investigate the role of multimodal virtual reality (VR) simulations and motor priming (MP) in an upper limb motor-imagery BCI task in order to maximize the engagement of sensory-motor networks in a broad range of patients who can benefit from virtual rehabilitation training. In order to investigate how different BCI paradigms impact brain activation, we designed 3 experimental conditions in a within-subject design, including an immersive Multimodal Virtual Reality with Motor Priming (VRMP) condition where users had to perform motor-execution before BCI training, an immersive Multimodal VR condition, and a control condition with standard 2D feedback. Further, these were also compared to overt motor-execution. Finally, a set of questionnaires were used to gather subjective data on Workload, Kinesthetic Imagery and Presence. Our findings show increased capacity to modulate and enhance brain activity patterns in all extracted EEG rhythms matching more closely those present during motor-execution and also a strong relationship between electrophysiological data and subjective experience. Our data suggest that both VR and particularly MP can enhance the activation of brain patterns present during overt motor-execution. Further, we show changes in the interhemispheric EEG balance, which might play an important role in the promotion of neural activation and neuroplastic changes in stroke patients in a motor-imagery neurofeedback paradigm. In addition, electrophysiological correlates of psychophysiological responses provide us with valuable information

  5. Spinal Metaplasticity in Respiratory Motor Control

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    Gordon S Mitchell

    2015-02-01

    Full Text Available A hallmark feature of the neural system controlling breathing is its ability to exhibit plasticity. Less appreciated is the ability to exhibit metaplasticity, a change in the capacity to express plasticity (ie. plastic plasticity. Recent advances in our understanding of cellular mechanisms giving rise to respiratory motor plasticity lay the groundwork for (ongoing investigations of metaplasticity. This detailed understanding of respiratory metaplasticity will be essential as we harness metaplasticity to restore breathing capacity in clinical disorders that compromise breathing, such as cervical spinal injury, motor neuron disease and other neuromuscular diseases. In this brief review, we discuss key examples of metaplasticity in respiratory motor control, and our current understanding of mechanisms giving rise to spinal plasticity and metaplasticity in phrenic motor output; particularly after pre-conditioning with intermittent hypoxia. Progress in this area has led to the realization that similar mechanisms are operative in other spinal motor networks, including those governing limb movement. Further, these mechanisms can be harnessed to restore respiratory and non-respiratory motor function after spinal injury.

  6. Non-invasive brain stimulation to promote motor and functional recovery following spinal cord injury

    Directory of Open Access Journals (Sweden)

    Aysegul Gunduz

    2017-01-01

    Full Text Available We conducted a systematic review of studies using non-invasive brain stimulation (NIBS: repetitive transcranial magnetic stimulation (rTMS and transcranial direct current stimulation (tDCS as a research and clinical tool aimed at improving motor and functional recovery or spasticity in patients following spinal cord injury (SCI under the assumption that if the residual corticospinal circuits could be stimulated appropriately, the changes might be accompanied by functional recovery or an improvement in spasticity. This review summarizes the literature on the changes induced by NIBS in the motor and functional recovery and spasticity control of the upper and lower extremities following SCI.

  7. High-temperature brushless DC motor controller

    Science.gov (United States)

    Cieslewski, Crzegorz; Lindblom, Scott C.; Maldonado, Frank J.; Eckert, Michael Nathan

    2017-05-16

    A motor control system for deployment in high temperature environments includes a controller; a first half-bridge circuit that includes a first high-side switching element and a first low-side switching element; a second half-bridge circuit that includes a second high-side switching element and a second low-side switching element; and a third half-bridge circuit that includes a third high-side switching element and a third; low-side switching element. The motor controller is arranged to apply a pulse width modulation (PWM) scheme to switch the first half-bridge circuit, second half-bridge circuit, and third half-bridge circuit to power a motor.

  8. Functional organization and restoration of the brain motor-execution network after stroke and rehabilitation

    Directory of Open Access Journals (Sweden)

    Sahil eBajaj

    2015-03-01

    Full Text Available Multiple cortical areas of the human brain motor system interact coherently in the low frequency range (< 0.1 Hz, even in the absence of explicit tasks. Following stroke, cortical interactions are functionally disturbed. How these interactions are affected and how the functional organization is regained from rehabilitative treatments as people begin to recover motor behaviors has not been systematically studied. We recorded the intrinsic functional magnetic resonance imaging (fMRI signals from 30 participants: 17 young healthy controls and 13 aged stroke survivors. Stroke participants underwent mental practice (MP or both mental practice and physical therapy (MP + PT within 14-51 days following stroke. We investigated the network activity of five core areas in the motor-execution network, consisting of the left primary motor area (LM1, the right primary motor area (RM1, the left pre-motor cortex (LPMC, the right pre-motor cortex (RPMC and the supplementary motor area (SMA. We discovered that (i the network activity dominated in the frequency range 0.06 Hz – 0.08 Hz for all the regions, and for both able-bodied and stroke participants (ii the causal information flow between the regions: LM1 and SMA, RPMC and SMA, RPMC and LM1, SMA and RM1, SMA and LPMC, was reduced significantly for stroke survivors (iii the flow did not increase significantly after MP alone and (iv the flow among the regions during MP+PT increased significantly. We also found that sensation and motor scores were significantly higher and correlated with directed functional connectivity measures when the stroke-survivors underwent MP+PT but not MP alone. The findings provide evidence that a combination of mental practice and physical therapy can be an effective means of treatment for stroke survivors to recover or regain the strength of motor behaviors, and that the spectra of causal information flow can be used as a reliable biomarker for evaluating rehabilitation in stroke

  9. Network connectivity and individual responses to brain stimulation in the human motor system.

    Science.gov (United States)

    Cárdenas-Morales, Lizbeth; Volz, Lukas J; Michely, Jochen; Rehme, Anne K; Pool, Eva-Maria; Nettekoven, Charlotte; Eickhoff, Simon B; Fink, Gereon R; Grefkes, Christian

    2014-07-01

    The mechanisms driving cortical plasticity in response to brain stimulation are still incompletely understood. We here explored whether neural activity and connectivity in the motor system relate to the magnitude of cortical plasticity induced by repetitive transcranial magnetic stimulation (rTMS). Twelve right-handed volunteers underwent functional magnetic resonance imaging during rest and while performing a simple hand motor task. Resting-state functional connectivity, task-induced activation, and task-related effective connectivity were assessed for a network of key motor areas. We then investigated the effects of intermittent theta-burst stimulation (iTBS) on motor-evoked potentials (MEP) for up to 25 min after stimulation over left primary motor cortex (M1) or parieto-occipital vertex (for control). ITBS-induced increases in MEP amplitudes correlated negatively with movement-related fMRI activity in left M1. Control iTBS had no effect on M1 excitability. Subjects with better response to M1-iTBS featured stronger preinterventional effective connectivity between left premotor areas and left M1. In contrast, resting-state connectivity did not predict iTBS aftereffects. Plasticity-related changes in M1 following brain stimulation seem to depend not only on local factors but also on interconnected brain regions. Predominantly activity-dependent properties of the cortical motor system are indicative of excitability changes following induction of cortical plasticity with rTMS. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Lost for emotion words: What motor and limbic brain activity reveals about autism and semantic theory

    Science.gov (United States)

    Moseley, Rachel L.; Shtyrov, Yury; Mohr, Bettina; Lombardo, Michael V.; Baron-Cohen, Simon; Pulvermüller, Friedemann

    2015-01-01

    Autism spectrum conditions (ASC) are characterised by deficits in understanding and expressing emotions and are frequently accompanied by alexithymia, a difficulty in understanding and expressing emotion words. Words are differentially represented in the brain according to their semantic category and these difficulties in ASC predict reduced activation to emotion-related words in limbic structures crucial for affective processing. Semantic theories view ‘emotion actions’ as critical for learning the semantic relationship between a word and the emotion it describes, such that emotion words typically activate the cortical motor systems involved in expressing emotion actions such as facial expressions. As ASC are also characterised by motor deficits and atypical brain structure and function in these regions, motor structures would also be expected to show reduced activation during emotion-semantic processing. Here we used event-related fMRI to compare passive processing of emotion words in comparison to abstract verbs and animal names in typically-developing controls and individuals with ASC. Relatively reduced brain activation in ASC for emotion words, but not matched control words, was found in motor areas and cingulate cortex specifically. The degree of activation evoked by emotion words in the motor system was also associated with the extent of autistic traits as revealed by the Autism Spectrum Quotient. We suggest that hypoactivation of motor and limbic regions for emotion word processing may underlie difficulties in processing emotional language in ASC. The role that sensorimotor systems and their connections might play in the affective and social-communication difficulties in ASC is discussed. PMID:25278250

  11. Nature of motor control: perspectives and issues.

    Science.gov (United States)

    Turvey, Michael T; Fonseca, Sergio

    2009-01-01

    Four perspectives on motor control provide the framework for developing a comprehensive theory of motor control in biological systems. The four perspectives, of decreasing orthodoxy, are distinguished by their sources of inspiration: neuroanatomy, robotics, self-organization, and ecological realities. Twelve major issues that commonly constrain (either explicitly or implicitly) the understanding of the control and coordination of movement are identified and evaluated within the framework of the four perspectives. The issues are as follows: (1) Is control strictly neural? (2) Is there a divide between planning and execution? (3) Does control entail a frequently involved knowledgeable executive? (4) Do analytical internal models mediate control? (5) Is anticipation necessarily model dependent? (6) Are movements preassembled? (7) Are the participating components context independent? (8) Is force transmission strictly myotendinous? (9) Is afference a matter of local linear signaling? (10) Is neural noise an impediment? (11) Do standard variables (of mechanics and physiology) suffice? (12) Is the organization of control hierarchical?

  12. Sliding Mode Control of Induction Motor Phase Currents

    DEFF Research Database (Denmark)

    Hansen, R.B.; Hattel, T.; Bork, J

    1995-01-01

    Sliding mode control of induction motor phase currents are investigated through development of two control concepts.......Sliding mode control of induction motor phase currents are investigated through development of two control concepts....

  13. Summary of electric vehicle dc motor-controller tests

    Science.gov (United States)

    Mcbrien, E. F.; Tryon, H. B.

    1982-01-01

    The differences in the performance of dc motors are evaluated when operating with chopper type controllers, and when operating on direct current. The interactions between the motor and the controller which cause these differences are investigated. Motor-controlled tests provided some of the data the quantified motor efficiency variations for both ripple free and chopper modes of operation.

  14. Laterality of brain activity during motor imagery is modulated by the provision of source level neurofeedback.

    Science.gov (United States)

    Boe, Shaun; Gionfriddo, Alicia; Kraeutner, Sarah; Tremblay, Antoine; Little, Graham; Bardouille, Timothy

    2014-11-01

    Motor imagery (MI) may be effective as an adjunct to physical practice for motor skill acquisition. For example, MI is emerging as an effective treatment in stroke neurorehabilitation. As in physical practice, the repetitive activation of neural pathways during MI can drive short- and long-term brain changes that underlie functional recovery. However, the lack of feedback about MI performance may be a factor limiting its effectiveness. The provision of feedback about MI-related brain activity may overcome this limitation by providing the opportunity for individuals to monitor their own performance of this endogenous process. We completed a controlled study to isolate neurofeedback as the factor driving changes in MI-related brain activity across repeated sessions. Eighteen healthy participants took part in 3 sessions comprised of both actual and imagined performance of a button press task. During MI, participants in the neurofeedback group received source level feedback based on activity from the left and right sensorimotor cortex obtained using magnetoencephalography. Participants in the control group received no neurofeedback. MI-related brain activity increased in the sensorimotor cortex contralateral to the imagined movement across sessions in the neurofeedback group, but not in controls. Task performance improved across sessions but did not differ between groups. Our results indicate that the provision of neurofeedback during MI allows healthy individuals to modulate regional brain activity. This finding has the potential to improve the effectiveness of MI as a tool in neurorehabilitation. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Motor Preparation Disrupts Proactive Control in the Stop Signal Task

    Directory of Open Access Journals (Sweden)

    Wuyi Wang

    2018-05-01

    Full Text Available In a study of the stop signal task (SST we employed Bayesian modeling to compute the estimated likelihood of stop signal or P(Stop trial by trial and identified regional processes of conflict anticipation and response slowing. A higher P(Stop is associated with prolonged go trial reaction time (goRT—a form of sequential effect—and reflects proactive control of motor response. However, some individuals do not demonstrate a sequential effect despite similar go and stop success (SS rates. We posited that motor preparation may disrupt proactive control more in certain individuals than others. Specifically, the time interval between trial and go signal onset—the fore-period (FP—varies across trials and a longer FP is associated with a higher level of motor preparation and shorter goRT. Greater motor preparatory activities may disrupt proactive control. To test this hypothesis, we compared brain activations and Granger causal connectivities of 81 adults who demonstrated a sequential effect (SEQ and 35 who did not (nSEQ. SEQ and nSEQ did not differ in regional activations to conflict anticipation, motor preparation, goRT slowing or goRT speeding. In contrast, SEQ and nSEQ demonstrated different patterns of Granger causal connectivities. P(Stop and FP activations shared reciprocal influence in SEQ but FP activities Granger caused P(Stop activities unidirectionally in nSEQ, and FP activities Granger caused goRT speeding activities in nSEQ but not SEQ. These findings support the hypothesis that motor preparation disrupts proactive control in nSEQ and provide direct neural evidence for interactive go and stop processes.

  16. Combined EEG-fNIRS Decoding of Motor Attempt and Imagery for Brain Switch Control: An Offline Study in Patients With Tetraplegia

    NARCIS (Netherlands)

    Blokland, Y.M.; Spyrou, L.; Thijssen, D.H.J.; Eijsvogels, T.M.; Colier, W.N.; Floor-Westerdijk, M.; Vlek, R.; Bruhn, J.; Farquhar, J.D.R.

    2014-01-01

    Combining electrophysiological and hemodynamic features is a novel approach for improving current performance of brain switches based on sensorimotor rhythms (SMR). This study was conducted with a dual purpose: to test the feasibility of using a combined electroencephalogram/functional near-infrared

  17. Combined EEG-fNIRS decoding of motor attempt and imagery for brain switch control: an offline study in patients with tetraplegia

    NARCIS (Netherlands)

    Blokland, Y.M.; Spyrou, L.; Thijssen, D.H.J.; Eijsvogels, T.M.H.; Colier, W.N.J.M.; Floor-Westerdijk, M.J.; Vlek, R.J.; Bruhn, J.; Farquhar, J.D.R.

    2014-01-01

    Combining electrophysiological and hemodynamic features is a novel approach for improving current performance of brain switches based on sensorimotor rhythms (SMR). This study was conducted with a dual purpose: to test the feasibility of using a combined electroencephalogram/functional near-infrared

  18. Brain versus Machine Control.

    Directory of Open Access Journals (Sweden)

    Jose M Carmena

    2004-12-01

    Full Text Available Dr. Octopus, the villain of the movie "Spiderman 2", is a fusion of man and machine. Neuroscientist Jose Carmena examines the facts behind this fictional account of a brain- machine interface

  19. Serotonergic modulation of spinal motor control

    DEFF Research Database (Denmark)

    Perrier, Jean-Francois Marie; Cotel, Florence

    2015-01-01

    Serotonin (5-HT) is a monoamine that powerfully modulates spinal motor control by acting on intrasynaptic and extrasynaptic receptors. Here we review the diversity of 5-HT actions on locomotor and motoneuronal activities. Two approaches have been used on in vitro spinal cord preparations: either...

  20. Emergence of Virtual Reality as a Tool for Upper Limb Rehabilitation: Incorporation of Motor Control and Motor Learning Principles

    Science.gov (United States)

    Weiss, Patrice L.; Keshner, Emily A.

    2015-01-01

    The primary focus of rehabilitation for individuals with loss of upper limb movement as a result of acquired brain injury is the relearning of specific motor skills and daily tasks. This relearning is essential because the loss of upper limb movement often results in a reduced quality of life. Although rehabilitation strives to take advantage of neuroplastic processes during recovery, results of traditional approaches to upper limb rehabilitation have not entirely met this goal. In contrast, enriched training tasks, simulated with a wide range of low- to high-end virtual reality–based simulations, can be used to provide meaningful, repetitive practice together with salient feedback, thereby maximizing neuroplastic processes via motor learning and motor recovery. Such enriched virtual environments have the potential to optimize motor learning by manipulating practice conditions that explicitly engage motivational, cognitive, motor control, and sensory feedback–based learning mechanisms. The objectives of this article are to review motor control and motor learning principles, to discuss how they can be exploited by virtual reality training environments, and to provide evidence concerning current applications for upper limb motor recovery. The limitations of the current technologies with respect to their effectiveness and transfer of learning to daily life tasks also are discussed. PMID:25212522

  1. Motor control theories and their applications.

    Science.gov (United States)

    Latash, Mark L; Levin, Mindy F; Scholz, John P; Schöner, Gregor

    2010-01-01

    We describe several influential hypotheses in the field of motor control including the equilibrium-point (referent configuration) hypothesis, the uncontrolled manifold hypothesis, and the idea of synergies based on the principle of motor abundance. The equilibrium-point hypothesis is based on the idea of control with thresholds for activation of neuronal pools; it provides a framework for analysis of both voluntary and involuntary movements. In particular, control of a single muscle can be adequately described with changes in the threshold of motor unit recruitment during slow muscle stretch (threshold of the tonic stretch reflex). Unlike the ideas of internal models, the equilibrium-point hypothesis does not assume neural computations of mechanical variables. The uncontrolled manifold hypothesis is based on the dynamic system approach to movements; it offers a toolbox to analyze synergic changes within redundant sets of elements related to stabilization of potentially important performance variables. The referent configuration hypothesis and the principle of abundance can be naturally combined into a single coherent scheme of control of multi-element systems. A body of experimental data on healthy persons and patients with movement disorders are reviewed in support of the mentioned hypotheses. In particular, movement disorders associated with spasticity are considered as consequences of an impaired ability to shift threshold of the tonic stretch reflex within the whole normal range. Technical details and applications of the mentioned hypo-theses to studies of motor learning are described. We view the mentioned hypotheses as the most promising ones in the field of motor control, based on a solid physical and neurophysiological foundation.

  2. Housing conditions influence motor functions and exploratory behavior following focal damage of the rat brain.

    Science.gov (United States)

    Gornicka-Pawlak, Elzbieta; Jabłońska, Anna; Chyliński, Andrzej; Domańska-Janik, Krystyna

    2009-01-01

    The present study investigated influence of housing conditions on motor functions recovery and exploratory behavior following ouabain focal brain lesion in the rat. During 30 days post-surgery period rats were housed individually in standard cages (IS) or in groups in enriched environment (EE) and behaviorally tested. The EE lesioned rats showed enhanced recovery from motor impairments in walking beam task, comparing with IS animals. Contrarily, in the open field IS rats (both lesioned and control) traveled a longer distance, showed less habituation and spent less time resting at the home base than the EE animals. Unlike the EE lesioned animals, the lesioned IS rats, presented a tendency to hyperactivity in postinjury period. Turning tendency was significantly affected by unilateral brain lesion only in the EE rats. We can conclude that housing conditions distinctly affected the rat's behavior in classical laboratory tests.

  3. Mechanosensation and Adaptive Motor Control in Insects.

    Science.gov (United States)

    Tuthill, John C; Wilson, Rachel I

    2016-10-24

    The ability of animals to flexibly navigate through complex environments depends on the integration of sensory information with motor commands. The sensory modality most tightly linked to motor control is mechanosensation. Adaptive motor control depends critically on an animal's ability to respond to mechanical forces generated both within and outside the body. The compact neural circuits of insects provide appealing systems to investigate how mechanical cues guide locomotion in rugged environments. Here, we review our current understanding of mechanosensation in insects and its role in adaptive motor control. We first examine the detection and encoding of mechanical forces by primary mechanoreceptor neurons. We then discuss how central circuits integrate and transform mechanosensory information to guide locomotion. Because most studies in this field have been performed in locusts, cockroaches, crickets, and stick insects, the examples we cite here are drawn mainly from these 'big insects'. However, we also pay particular attention to the tiny fruit fly, Drosophila, where new tools are creating new opportunities, particularly for understanding central circuits. Our aim is to show how studies of big insects have yielded fundamental insights relevant to mechanosensation in all animals, and also to point out how the Drosophila toolkit can contribute to future progress in understanding mechanosensory processing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. DC Motor control using motor-generator set with controlled generator field

    Science.gov (United States)

    Belsterling, Charles A.; Stone, John

    1982-01-01

    A d.c. generator is connected in series opposed to the polarity of a d.c. power source supplying a d.c. drive motor. The generator is part of a motor-generator set, the motor of which is supplied from the power source connected to the motor. A generator field control means varies the field produced by at least one of the generator windings in order to change the effective voltage output. When the generator voltage is exactly equal to the d.c. voltage supply, no voltage is applied across the drive motor. As the field of the generator is reduced, the drive motor is supplied greater voltage until the full voltage of the d.c. power source is supplied when the generator has zero field applied. Additional voltage may be applied across the drive motor by reversing and increasing the reversed field on the generator. The drive motor may be reversed in direction from standstill by increasing the generator field so that a reverse voltage is applied across the d.c. motor.

  5. Illusory movement perception improves motor control for prosthetic hands.

    Science.gov (United States)

    Marasco, Paul D; Hebert, Jacqueline S; Sensinger, Jon W; Shell, Courtney E; Schofield, Jonathon S; Thumser, Zachary C; Nataraj, Raviraj; Beckler, Dylan T; Dawson, Michael R; Blustein, Dan H; Gill, Satinder; Mensh, Brett D; Granja-Vazquez, Rafael; Newcomb, Madeline D; Carey, Jason P; Orzell, Beth M

    2018-03-14

    To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement's progress. This largely nonconscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. We report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  6. Arm coordination in octopus crawling involves unique motor control strategies.

    Science.gov (United States)

    Levy, Guy; Flash, Tamar; Hochner, Binyamin

    2015-05-04

    To cope with the exceptional computational complexity that is involved in the control of its hyper-redundant arms [1], the octopus has adopted unique motor control strategies in which the central brain activates rather autonomous motor programs in the elaborated peripheral nervous system of the arms [2, 3]. How octopuses coordinate their eight long and flexible arms in locomotion is still unknown. Here, we present the first detailed kinematic analysis of octopus arm coordination in crawling. The results are surprising in several respects: (1) despite its bilaterally symmetrical body, the octopus can crawl in any direction relative to its body orientation; (2) body and crawling orientation are monotonically and independently controlled; and (3) contrasting known animal locomotion, octopus crawling lacks any apparent rhythmical patterns in limb coordination, suggesting a unique non-rhythmical output of the octopus central controller. We show that this uncommon maneuverability is derived from the radial symmetry of the arms around the body and the simple pushing-by-elongation mechanism by which the arms create the crawling thrust. These two together enable a mechanism whereby the central controller chooses in a moment-to-moment fashion which arms to recruit for pushing the body in an instantaneous direction. Our findings suggest that the soft molluscan body has affected in an embodied way [4, 5] the emergence of the adaptive motor behavior of the octopus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Brushless DC motor speed control strategy of simulation research

    Directory of Open Access Journals (Sweden)

    Xiang Wen

    2017-01-01

    Full Text Available In view of the brushless DC motor speed regulation problem, an ideal control strategy is designed. Through the model and analysis of Brushless DC motor, the mathematical model of the brushless DC motor is obtained. By comparing three control strategies of PID control strategy, fuzzy control strategy and fuzzy PID control strategy, PID controller, fuzzy controller and fuzzy PID controller are designed respectively for simulation test. The simulation results show that the fuzzy PID controller has good control effect.

  8. Structural and functional brain signatures of C9orf72 in motor neuron disease.

    Science.gov (United States)

    Agosta, Federica; Ferraro, Pilar M; Riva, Nilo; Spinelli, Edoardo Gioele; Domi, Teuta; Carrera, Paola; Copetti, Massimiliano; Falzone, Yuri; Ferrari, Maurizio; Lunetta, Christian; Comi, Giancarlo; Falini, Andrea; Quattrini, Angelo; Filippi, Massimo

    2017-09-01

    This study investigated structural and functional magnetic resonance imaging abnormalities in hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9orf72) motor neuron disease (MND) relative to disease severity-matched sporadic MND cases. We enrolled 19 C9orf72 and 67 disease severity-matched sporadic MND patients, and 22 controls. Sporadic cases were grouped in patients with: no cognitive/behavioral deficits (sporadic-motor); same patterns of cognitive/behavioral impairment as C9orf72 cases (sporadic-cognitive); shorter disease duration versus other sporadic groups (sporadic-early). C9orf72 patients showed cerebellar and thalamic atrophy versus all sporadic cases. All MND patients showed motor, frontal, and temporoparietal cortical thinning and motor and extramotor white matter damage versus controls, independent of genotype and presence of cognitive impairment. Compared with sporadic-early, C9orf72 patients revealed an occipital cortical thinning. C9orf72 patients had enhanced visual network functional connectivity versus sporadic-motor and sporadic-early cases. Structural cerebellar and thalamic damage and posterior cortical alterations are the brain magnetic resonance imaging signatures of C9orf72 MND. Frontotemporal cortical and widespread white matter involvement are likely to be an effect of the disease evolution rather than a C9orf72 marker. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. How do glial cells contribute to motor control?

    DEFF Research Database (Denmark)

    Christensen, Rasmus Kordt; Petersen, Anders Victor; Perrier, Jean-Francois Marie

    2013-01-01

    that glia play an active role in several physiological functions. The discovery that a bidirectional communication takes place between astrocytes (the star shaped glial cell of the brain) and neurons, was a major breakthrough in the field of synaptic physiology. Astrocytes express receptors that get...... activated by neurotransmitters during synaptic transmission. In turn they release other transmitters - called gliotransmitters - that bind to neuronal receptors and modulate synaptic transmission. This feedback, which led to the concept of the tripartite synapse, has been reported with various transmitters...... including glutamate, ATP, GABA or serine. In the present review we will focus on astrocytes and review the evidence suggesting and demonstrating their role in motor control. Rhythmic motor behaviors such as locomotion, swimming or chewing are generated by networks of neurons termed central pattern...

  10. Non-invasive brain stimulation of motor cortex induces embodiment when integrated with virtual reality feedback.

    Science.gov (United States)

    Bassolino, M; Franza, M; Bello Ruiz, J; Pinardi, M; Schmidlin, T; Stephan, M A; Solcà, M; Serino, A; Blanke, O

    2018-04-01

    Previous evidence highlighted the multisensory-motor origin of embodiment - that is, the experience of having a body and of being in control of it - and the possibility of experimentally manipulating it. For instance, an illusory feeling of embodiment towards a fake hand can be triggered by providing synchronous visuo-tactile stimulation to the hand of participants and to a fake hand or by asking participants to move their hand and observe a fake hand moving accordingly (rubber hand illusion). Here, we tested whether it is possible to manipulate embodiment not through stimulation of the participant's hand, but by directly tapping into the brain's hand representation via non-invasive brain stimulation. To this aim, we combined transcranial magnetic stimulation (TMS), to activate the hand corticospinal representation, with virtual reality (VR), to provide matching (as contrasted to non-matching) visual feedback, mimicking involuntary hand movements evoked by TMS. We show that the illusory embodiment occurred when TMS pulses were temporally matched with VR feedback, but not when TMS was administered outside primary motor cortex, (over the vertex) or when stimulating motor cortex at a lower intensity (that did not activate peripheral muscles). Behavioural (questionnaires) and neurophysiological (motor-evoked-potentials, TMS-evoked-movements) measures further indicated that embodiment was not explained by stimulation per se, but depended on the temporal coherence between TMS-induced activation of hand corticospinal representation and the virtual bodily feedback. This reveals that non-invasive brain stimulation may replace the application of external tactile hand cues and motor components related to volition, planning and anticipation. © 2018 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  11. The "handwriting brain": a meta-analysis of neuroimaging studies of motor versus orthographic processes.

    Science.gov (United States)

    Planton, Samuel; Jucla, Mélanie; Roux, Franck-Emmanuel; Démonet, Jean-François

    2013-01-01

    Handwriting is a modality of language production whose cerebral substrates remain poorly known although the existence of specific regions is postulated. The description of brain damaged patients with agraphia and, more recently, several neuroimaging studies suggest the involvement of different brain regions. However, results vary with the methodological choices made and may not always discriminate between "writing-specific" and motor or linguistic processes shared with other abilities. We used the "Activation Likelihood Estimate" (ALE) meta-analytical method to identify the cerebral network of areas commonly activated during handwriting in 18 neuroimaging studies published in the literature. Included contrasts were also classified according to the control tasks used, whether non-specific motor/output-control or linguistic/input-control. These data were included in two secondary meta-analyses in order to reveal the functional role of the different areas of this network. An extensive, mainly left-hemisphere network of 12 cortical and sub-cortical areas was obtained; three of which were considered as primarily writing-specific (left superior frontal sulcus/middle frontal gyrus area, left intraparietal sulcus/superior parietal area, right cerebellum) while others related rather to non-specific motor (primary motor and sensorimotor cortex, supplementary motor area, thalamus and putamen) or linguistic processes (ventral premotor cortex, posterior/inferior temporal cortex). This meta-analysis provides a description of the cerebral network of handwriting as revealed by various types of neuroimaging experiments and confirms the crucial involvement of the left frontal and superior parietal regions. These findings provide new insights into cognitive processes involved in handwriting and their cerebral substrates. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Computer controlled motor vehicle battery circuit

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, W.R.; McAuiliffe, G.N.; Schlageter, G.A.

    1986-04-01

    This patent consists of a motor vehicle having a DC motor, a pedal biased to a released position and depressed by the driver to increase speed. An alternate switching means affects the vehicle speed control, a foot switch is operated by the pedal and operative when the pedal is depressed to close a circuit enabling energization of the alternate switching means. A microprocessor includes a program for controlling operation of the alternate switching means, the foot switch is operative when the pedal is released to open the enabling circuit. The program includes a register which is incremented with each passage of the logic and is responsive to the incremented count in the register to instruct a change in position of the alternate switching means.

  13. Substantiation of Structure of Adaptive Control Systems for Motor Units

    Science.gov (United States)

    Ovsyannikov, S. I.

    2018-05-01

    The article describes the development of new electronic control systems, in particular motor units, for small-sized agricultural equipment. Based on the analysis of traffic control systems, the main course of development of the conceptual designs of motor units has been defined. The systems aimed to control the course motion of the motor unit in automatic mode using the adaptive systems have been developed. The article presents structural models of the conceptual motor units based on electrically controlled systems by the operation of drive motors and adaptive systems that make the motor units completely automated.

  14. DC motors and servo-motors controlled by Raspberry Pi 2B

    Directory of Open Access Journals (Sweden)

    Šustek Michal

    2017-01-01

    Full Text Available The expanding capabilities of today’s microcontrollers and other devices lead to an increased utilization of these technologies in diverse fields. The automation and issue of remote control of moving objects belong to these fields. In this project, a microcontroller Raspberry Pi 2B was chosen for controlling DC motors and servo-motors. This paper provides basic insight into issue of controlling DC motors and servo-motors, connection between Raspberry and other components on breadboard and programming syntaxes for controlling motors in Python programming language.

  15. Sensorless V/f Control of Permanent Magnet Synchronous Motors

    OpenAIRE

    Montesinos-Miracle, Daniel; Perera, P. D. Chandana; Galceran-Arellano, Samuel; Blaabjerg, Frede

    2010-01-01

    V/f control strategy for permanent magnet synchronous motors can be useful for HVAC applications, where not high performance is required. Permanent magnet synchronous motors have efficiency advantages over the induction motor. But open loop V/f control is not stable in the whole frequency range. As demonstrated, the V/f control strategy becomes

  16. A New Approach to Laboratory Motor Control MMCS: The Modular Motor Control System

    Science.gov (United States)

    1989-02-01

    encB2 encl2 h/beat2 J2 . h/ beatl encll encBl encAl 0 = LED indicator connectors to motor/enc Figure 5.2: Motor interface board layout something is...signal for joint 1. h/ beatl Green Heartbeat signal for joint 1. h/beat2 Green Heartbeat signal for joint 2. gpl Red General purpose (software controllable

  17. Design and control of a superconducting permanent magnet synchronous motor

    International Nuclear Information System (INIS)

    Jiang, Y; Pei, R; Hong, Z; Song, J; Fang, F; Coombs, T A

    2007-01-01

    This paper gives a detailed description of the design of a superconducting permanent magnet synchronous motor. The parameters of the motor have been identified, and the torque equation has been stated. A direct torque control algorithm is introduced and applied to a traditional permanent magnet synchronous motor and the superconducting permanent magnet synchronous motor described in this paper. The motor performance shows that the direct torque control algorithm provides excellent control to the superconducting motor, and guarantees that the magnitude of the operational armature currents is smaller than the value of the critical current of the superconducting tape used for stator winding

  18. Design and control of a superconducting permanent magnet synchronous motor

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Y [Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom); Pei, R [Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom); Hong, Z [Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom); Song, J [Huazhong University of Science of Technology, Wuhan 430074 (China); Fang, F [Huazhong University of Science of Technology, Wuhan 430074 (China); Coombs, T A [Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom)

    2007-07-15

    This paper gives a detailed description of the design of a superconducting permanent magnet synchronous motor. The parameters of the motor have been identified, and the torque equation has been stated. A direct torque control algorithm is introduced and applied to a traditional permanent magnet synchronous motor and the superconducting permanent magnet synchronous motor described in this paper. The motor performance shows that the direct torque control algorithm provides excellent control to the superconducting motor, and guarantees that the magnitude of the operational armature currents is smaller than the value of the critical current of the superconducting tape used for stator winding.

  19. Nonlinear Deadbeat Current Control of a Switched Reluctance Motor

    OpenAIRE

    Rudolph, Benjamin

    2009-01-01

    High performance current control is critical to the success of the switched reluctance motor (SRM). Yet high motor phase nonlinearities in the SRM place extra burden on the current controller, rendering it the weakest link in SRM control. In contrast to linear motor control techniques that respond to current error, the deadbeat controller calculates the control voltage by the current command, phase current, rotor position and applied phase voltage. The deadbeat controller has demonstrated sup...

  20. Neurobiology: motor control of flexible octopus arms.

    Science.gov (United States)

    Sumbre, Germán; Fiorito, Graziano; Flash, Tamar; Hochner, Binyamin

    2005-02-10

    Animals with rigid skeletons can rely on several mechanisms to simplify motor control--for example, they have skeletal joints that reduce the number of variables and degrees of freedom that need to be controlled. Here we show that when the octopus uses one of its long and highly flexible arms to transfer an object from one place to another, it employs a vertebrate-like strategy, temporarily reconfiguring its arm into a stiffened, articulated, quasi-jointed structure. This indicates that an articulated limb may provide an optimal solution for achieving precise, point-to-point movements.

  1. Discerning measures of conscious brain processes associated with superior early motor performance: Capacity, coactivation, and character.

    Science.gov (United States)

    van Duijn, Tina; Buszard, Tim; Hoskens, Merel C J; Masters, Rich S W

    2017-01-01

    This study explored the relationship between working memory (WM) capacity, corticocortical communication (EEG coherence), and propensity for conscious control of movement during the performance of a complex far-aiming task. We were specifically interested in the role of these variables in predicting motor performance by novices. Forty-eight participants completed (a) an assessment of WM capacity (an adapted Rotation Span task), (b) a questionnaire that assessed the propensity to consciously control movement (the Movement Specific Reinvestment Scale), and (c) a hockey push-pass task. The hockey push-pass task was performed in a single task (movement only) condition and a combined task (movement plus decision) condition. Electroencephalography (EEG) was used to examine brain activity during the single task. WM capacity best predicted single task performance. WM capacity in combination with T8-Fz coherence (between the visuospatial and motor regions of the brain) best predicted combined task performance. We discuss the implied roles of visuospatial information processing capacity, neural coactivation, and propensity for conscious processing during performance of complex motor tasks. © 2017 Elsevier B.V. All rights reserved.

  2. [Predictive ocular motor control in Parkinson's disease].

    Science.gov (United States)

    Ying, Li; Liu, Zhen-Guo; Chen, Wei; Gan, Jing; Wang, Wen-An

    2008-02-19

    To investigate the changes of predictive ocular motor function in the patients with Parkinson's disease (PD), and to discuss its clinical value. Videonystagmography (VNG) was used to examine 24 patients with idiopathic Parkinson's disease, 15 males and 9 females, aged 61 +/- 6 (50-69), and 24 sex and age-matched healthy control subjects on random ocular saccade (with the target moving at random intervals to random positions) and predictive ocular saccade (with the 1.25-second light target moving 10 degrees right or left from the center). In the random ocular saccade program, the latency of saccade of the PD patients was 284 ms +/- 58 ms, significantly longer than that of the healthy controls (236 ms +/- 37 ms, P = 0.003). In the predictive ocular saccade pattern, the latency of saccades the PD patients was 150 ms +/- 138 ms, significantly longer than that of the healthy controls (59 ms +/- 102 ms, P = 0.002). The appearance rate of predictive saccades (with the latency of saccade <80 ms) in the PD group was 21%, significantly lower than that in the control group (31%, P = 0.003). There is dysfunction of predictive ocular motor control in the PD patients, and the cognitive function may be impaired at the early stage of PD.

  3. Permanent magnet brushless DC motor drives and controls

    CERN Document Server

    Xia, Chang-liang

    2012-01-01

    An advanced introduction to the simulation and hardware implementation of BLDC motor drives A thorough reference on the simulation and hardware implementation of BLDC motor drives, this book covers recent advances in the control of BLDC motor drives, including intelligent control, sensorless control, torque ripple reduction and hardware implementation. With the guidance of the expert author team, readers will understand the principle, modelling, design and control of BLDC motor drives. The advanced control methods and new achievements of BLDC motor drives, of interest to more a

  4. Neuron-specific caveolin-1 overexpression improves motor function and preserves memory in mice subjected to brain trauma.

    Science.gov (United States)

    Egawa, Junji; Schilling, Jan M; Cui, Weihua; Posadas, Edmund; Sawada, Atsushi; Alas, Basheer; Zemljic-Harpf, Alice E; Fannon-Pavlich, McKenzie J; Mandyam, Chitra D; Roth, David M; Patel, Hemal H; Patel, Piyush M; Head, Brian P

    2017-08-01

    Studies in vitro and in vivo demonstrate that membrane/lipid rafts and caveolin (Cav) organize progrowth receptors, and, when overexpressed specifically in neurons, Cav-1 augments neuronal signaling and growth and improves cognitive function in adult and aged mice; however, whether neuronal Cav-1 overexpression can preserve motor and cognitive function in the brain trauma setting is unknown. Here, we generated a neuron-targeted Cav-1-overexpressing transgenic (Tg) mouse [synapsin-driven Cav-1 (SynCav1 Tg)] and subjected it to a controlled cortical impact model of brain trauma and measured biochemical, anatomic, and behavioral changes. SynCav1 Tg mice exhibited increased hippocampal expression of Cav-1 and membrane/lipid raft localization of postsynaptic density protein 95, NMDA receptor, and tropomyosin receptor kinase B. When subjected to a controlled cortical impact, SynCav1 Tg mice demonstrated preserved hippocampus-dependent fear learning and memory, improved motor function recovery, and decreased brain lesion volume compared with wild-type controls. Neuron-targeted overexpression of Cav-1 in the adult brain prevents hippocampus-dependent learning and memory deficits, restores motor function after brain trauma, and decreases brain lesion size induced by trauma. Our findings demonstrate that neuron-targeted Cav-1 can be used as a novel therapeutic strategy to restore brain function and prevent trauma-associated maladaptive plasticity.-Egawa, J., Schilling, J. M., Cui, W., Posadas, E., Sawada, A., Alas, B., Zemljic-Harpf, A. E., Fannon-Pavlich, M. J., Mandyam, C. D., Roth, D. M., Patel, H. H., Patel, P. M., Head, B. P. Neuron-specific caveolin-1 overexpression improves motor function and preserves memory in mice subjected to brain trauma. © FASEB.

  5. Improved Rotor Speed Brushless DC Motor Using Fuzzy Controller

    Directory of Open Access Journals (Sweden)

    Jafar Mostafapour

    2015-04-01

    Full Text Available A brushless DC (BLDC Motors have advantages over brushed, Direct current (DC Motors and , Induction motor (IM. They have better speed verses torque characteristics, high dynamic response, high efficiency, long operating life, noiseless operation, higher speed ranges, and rugged construction. Also, torque delivered to motor size is higher, making it useful in application where space and weight are critical factors. With these advantages BLDC motors find wide spread application in automotive appliance, aerospace medical, and instrumentation and automation industries This paper can be seen as fuzzy controllers compared to PI control BLDC motor rotor speed has improved significantly and beter result can be achieve.

  6. Robust position control of induction motor using fuzzy logic control

    International Nuclear Information System (INIS)

    Kim, Sei Chan; Kim, Duk Hun; Yang, Seung Ho; Won, Chung Yuen

    1993-01-01

    In recent years, fuzzy logic or fuzzy set theory has reveived attention of a number of researchers in the area of power electronics and motion control. The paper describes a vector-controlled induction motor position servo drive where fuzzy control is used to get robustness against parameter variation and load torque disturbance effects. Both coarse and fine control with the help of look-up rule tables are used to improve transient response and system settling time. The performance characteristics are then compared with those of proportional-integral(PI) control. The simulation results clearly indicate the superiority of fuzzy control with larger number of rules. The fuzzy controller was implemented with a 16-bit microprocessor and tested in laboratory on a 3-hp IGBT inverter induction motor drive system. The test results verify the simulation performance. (Author)

  7. Theobromine up-regulates cerebral brain-derived neurotrophic factor and facilitates motor learning in mice.

    Science.gov (United States)

    Yoneda, Mitsugu; Sugimoto, Naotoshi; Katakura, Masanori; Matsuzaki, Kentaro; Tanigami, Hayate; Yachie, Akihiro; Ohno-Shosaku, Takako; Shido, Osamu

    2017-01-01

    Theobromine, which is a caffeine derivative, is the primary methylxanthine produced by Theobroma cacao. Theobromine works as a phosphodiesterase (PDE) inhibitor to increase intracellular cyclic adenosine monophosphate (cAMP). cAMP activates the cAMP-response element-binding protein (CREB), which is involved in a large variety of brain processes, including the induction of the brain-derived neurotrophic factor (BDNF). BDNF supports cell survival and neuronal functions, including learning and memory. Thus, cAMP/CREB/BDNF pathways play an important role in learning and memory. Here, we investigated whether orally administered theobromine could act as a PDE inhibitor centrally and affect cAMP/CREB/BDNF pathways and learning behavior in mice. The mice were divided into two groups. The control group (CN) was fed a normal diet, whereas the theobromine group (TB) was fed a diet supplemented with 0.05% theobromine for 30 days. We measured the levels of theobromine, phosphorylated vasodilator-stimulated phosphoprotein (p-VASP), phosphorylated CREB (p-CREB), and BDNF in the brain. p-VASP was used as an index of cAMP increases. Moreover, we analyzed the performance of the mice on a three-lever motor learning task. Theobromine was detectable in the brains of TB mice. The brain levels of p-VASP, p-CREB, and BDNF were higher in the TB mice compared with those in the CN mice. In addition, the TB mice performed better on the three-lever task than the CN mice did. These results strongly suggested that orally administered theobromine acted as a PDE inhibitor in the brain, and it augmented the cAMP/CREB/BDNF pathways and motor learning in mice. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. The Basal Ganglia and Adaptive Motor Control

    Science.gov (United States)

    Graybiel, Ann M.; Aosaki, Toshihiko; Flaherty, Alice W.; Kimura, Minoru

    1994-09-01

    The basal ganglia are neural structures within the motor and cognitive control circuits in the mammalian forebrain and are interconnected with the neocortex by multiple loops. Dysfunction in these parallel loops caused by damage to the striatum results in major defects in voluntary movement, exemplified in Parkinson's disease and Huntington's disease. These parallel loops have a distributed modular architecture resembling local expert architectures of computational learning models. During sensorimotor learning, such distributed networks may be coordinated by widely spaced striatal interneurons that acquire response properties on the basis of experienced reward.

  9. Different brain circuits underlie motor and perceptual representations of temporal intervals

    DEFF Research Database (Denmark)

    Bueti, Doemnica; Walsh, Vincent; Frith, Christopher

    2008-01-01

    V5/MT. Our findings point to a role for the parietal cortex as an interface between sensory and motor processes and suggest that it may be a key node in translation of temporal information into action. Furthermore, we discuss the potential importance of the extrastriate cortex in processing visual......In everyday life, temporal information is used for both perception and action, but whether these two functions reflect the operation of similar or different neural circuits is unclear. We used functional magnetic resonance imaging to investigate the neural correlates of processing temporal...... information when either a motor or a perceptual representation is used. Participants viewed two identical sequences of visual stimuli and used the information differently to perform either a temporal reproduction or a temporal estimation task. By comparing brain activity evoked by these tasks and control...

  10. Therapeutic deep brain stimulation in Parkinsonian rats directly influences motor cortex.

    Science.gov (United States)

    Li, Qian; Ke, Ya; Chan, Danny C W; Qian, Zhong-Ming; Yung, Ken K L; Ko, Ho; Arbuthnott, Gordon W; Yung, Wing-Ho

    2012-12-06

    Much recent discussion about the origin of Parkinsonian symptoms has centered around the idea that they arise with the increase of beta frequency waves in the EEG. This activity may be closely related to an oscillation between subthalamic nucleus (STN) and globus pallidus. Since STN is the target of deep brain stimulation, it had been assumed that its action is on the nucleus itself. By means of simultaneous recordings of the firing activities from populations of neurons and the local field potentials in the motor cortex of freely moving Parkinsonian rats, this study casts doubt on this assumption. Instead, we found evidence that the corrective action is upon the cortex, where stochastic antidromic spikes originating from the STN directly modify the firing probability of the corticofugal projection neurons, destroy the dominance of beta rhythm, and thus restore motor control to the subjects, be they patients or rodents. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Tracking control of DC motors via mimo nonlinear fuzzy control

    International Nuclear Information System (INIS)

    Harb, Ahmad M.; Smadi, Issam A.

    2009-01-01

    This paper proposed a nonlinear controller for speed tracking of separately excited DC motors (SEDCM's) using the multi-input multi-output (MIMO) fuzzy logic controller (FLC's). Based on a nonlinear mathematical model of SEDCM, a FLC is designed to achieve high performance speed tracking through rejection load disturbance. Computer simulations are presented to show speed tracking performance and the effectiveness of the proposed controller.

  12. EEG datasets for motor imagery brain-computer interface.

    Science.gov (United States)

    Cho, Hohyun; Ahn, Minkyu; Ahn, Sangtae; Kwon, Moonyoung; Jun, Sung Chan

    2017-07-01

    Most investigators of brain-computer interface (BCI) research believe that BCI can be achieved through induced neuronal activity from the cortex, but not by evoked neuronal activity. Motor imagery (MI)-based BCI is one of the standard concepts of BCI, in that the user can generate induced activity by imagining motor movements. However, variations in performance over sessions and subjects are too severe to overcome easily; therefore, a basic understanding and investigation of BCI performance variation is necessary to find critical evidence of performance variation. Here we present not only EEG datasets for MI BCI from 52 subjects, but also the results of a psychological and physiological questionnaire, EMG datasets, the locations of 3D EEG electrodes, and EEGs for non-task-related states. We validated our EEG datasets by using the percentage of bad trials, event-related desynchronization/synchronization (ERD/ERS) analysis, and classification analysis. After conventional rejection of bad trials, we showed contralateral ERD and ipsilateral ERS in the somatosensory area, which are well-known patterns of MI. Finally, we showed that 73.08% of datasets (38 subjects) included reasonably discriminative information. Our EEG datasets included the information necessary to determine statistical significance; they consisted of well-discriminated datasets (38 subjects) and less-discriminative datasets. These may provide researchers with opportunities to investigate human factors related to MI BCI performance variation, and may also achieve subject-to-subject transfer by using metadata, including a questionnaire, EEG coordinates, and EEGs for non-task-related states. © The Authors 2017. Published by Oxford University Press.

  13. Integrated-Circuit Controller For Brushless dc Motor

    Science.gov (United States)

    Le, Dong Tuan

    1994-01-01

    Generic circuit performs commutation-logic and power-switching functions for control of brushless dc motor. Controller includes commutation-logic and associated control circuitry, power supply, and inverters containing power transistors. Major advantages of controller are size, weight, and power consumption can be made less than other brushless-dc-motor controllers.

  14. The effects of voluntary, involuntary, and forced exercises on brain-derived neurotrophic factor and motor function recovery: a rat brain ischemia model.

    Directory of Open Access Journals (Sweden)

    Zheng Ke

    Full Text Available BACKGROUND: Stroke rehabilitation with different exercise paradigms has been investigated, but which one is more effective in facilitating motor recovery and up-regulating brain neurotrophic factor (BDNF after brain ischemia would be interesting to clinicians and patients. Voluntary exercise, forced exercise, and involuntary muscle movement caused by functional electrical stimulation (FES have been individually demonstrated effective as stroke rehabilitation intervention. The aim of this study was to investigate the effects of these three common interventions on brain BDNF changes and motor recovery levels using a rat ischemic stroke model. METHODOLOGY/PRINCIPAL FINDINGS: One hundred and seventeen Sprague-Dawley rats were randomly distributed into four groups: Control (Con, Voluntary exercise of wheel running (V-Ex, Forced exercise of treadmill running (F-Ex, and Involuntary exercise of FES (I-Ex with implanted electrodes placed in two hind limb muscles on the affected side to mimic gait-like walking pattern during stimulation. Ischemic stroke was induced in all rats with the middle cerebral artery occlusion/reperfusion model and fifty-seven rats had motor deficits after stroke. Twenty-four hours after reperfusion, rats were arranged to their intervention programs. De Ryck's behavioral test was conducted daily during the 7-day intervention as an evaluation tool of motor recovery. Serum corticosterone concentration and BDNF levels in the hippocampus, striatum, and cortex were measured after the rats were sacrificed. V-Ex had significantly better motor recovery in the behavioral test. V-Ex also had significantly higher hippocampal BDNF concentration than F-Ex and Con. F-Ex had significantly higher serum corticosterone level than other groups. CONCLUSION/SIGNIFICANCE: Voluntary exercise is the most effective intervention in upregulating the hippocampal BDNF level, and facilitating motor recovery. Rats that exercised voluntarily also showed less

  15. Fine motor assessment in chronic wrist pain: the role of adapted motor control

    NARCIS (Netherlands)

    Smeulders, M. J.; Kreulen, M.; Bos, K. E.

    2001-01-01

    To show whether a difference in fine motor control exists between patients with chronic, undiagnosed wrist pain (CUWP) and healthy controls. Furthermore, a method to assess fine motor function of the wrist is evaluated. A case-control study. The Academic Medical Center in Amsterdam, the Netherlands.

  16. Controller for a High-Power, Brushless dc Motor

    Science.gov (United States)

    Fleming, David J.; Makdad, Terence A.

    1987-01-01

    Driving and braking torques controllable. Control circuit operates 7-kW, 45-lb-ft (61-N-m), three-phase, brushless dc motor in both motor and generator modes. In motor modes, energy from power source is pulse-width modulated to motor through modified "H-bridge" circuit, in generator mode, energy from motor is pulse-width modulated into bank of load resistors to provide variable braking torques. Circuit provides high-resolution torque control in both directions over wide range of speeds and torques. Tested successfully at bus voltages up to 200 Vdc and currents up to 45 A.

  17. Controllable molecular motors engineered from myosin and RNA

    Science.gov (United States)

    Omabegho, Tosan; Gurel, Pinar S.; Cheng, Clarence Y.; Kim, Laura Y.; Ruijgrok, Paul V.; Das, Rhiju; Alushin, Gregory M.; Bryant, Zev

    2018-01-01

    Engineering biomolecular motors can provide direct tests of structure-function relationships and customized components for controlling molecular transport in artificial systems1 or in living cells2. Previously, synthetic nucleic acid motors3-5 and modified natural protein motors6-10 have been developed in separate complementary strategies to achieve tunable and controllable motor function. Integrating protein and nucleic-acid components to form engineered nucleoprotein motors may enable additional sophisticated functionalities. However, this potential has only begun to be explored in pioneering work harnessing DNA scaffolds to dictate the spacing, number and composition of tethered protein motors11-15. Here, we describe myosin motors that incorporate RNA lever arms, forming hybrid assemblies in which conformational changes in the protein motor domain are amplified and redirected by nucleic acid structures. The RNA lever arm geometry determines the speed and direction of motor transport and can be dynamically controlled using programmed transitions in the lever arm structure7,9. We have characterized the hybrid motors using in vitro motility assays, single-molecule tracking, cryo-electron microscopy and structural probing16. Our designs include nucleoprotein motors that reversibly change direction in response to oligonucleotides that drive strand-displacement17 reactions. In multimeric assemblies, the controllable motors walk processively along actin filaments at speeds of 10-20 nm s-1. Finally, to illustrate the potential for multiplexed addressable control, we demonstrate sequence-specific responses of RNA variants to oligonucleotide signals.

  18. Functional and Structural Brain Plasticity Enhanced by Motor and Cognitive Rehabilitation in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Luca Prosperini

    2015-01-01

    Full Text Available Rehabilitation is recognized to be important in ameliorating motor and cognitive functions, reducing disease burden, and improving quality of life in patients with multiple sclerosis (MS. In this systematic review, we summarize the existing evidences that motor and cognitive rehabilitation may enhance functional and structural brain plasticity in patients with MS, as assessed by means of the most advanced neuroimaging techniques, including diffusion tensor imaging and task-related and resting-state functional magnetic resonance imaging (MRI. In most cases, the rehabilitation program was based on computer-assisted/video game exercises performed in either an outpatient or home setting. Despite their heterogeneity, all the included studies describe changes in white matter microarchitecture, in task-related activation, and/or in functional connectivity following both task-oriented and selective training. When explored, relevant correlation between improved function and MRI-detected brain changes was often found, supporting the hypothesis that training-induced brain plasticity is specifically linked to the trained domain. Small sample sizes, lack of randomization and/or an active control group, as well as missed relationship between MRI-detected changes and clinical performance, are the major drawbacks of the selected studies. Knowledge gaps in this field of research are also discussed to provide a framework for future investigations.

  19. Permanent magnet DC motor control by using arduino and motor drive module BTS7960

    Science.gov (United States)

    Syukriyadin, S.; Syahrizal, S.; Mansur, G.; Ramadhan, H. P.

    2018-05-01

    This study proposes a control system for permanent magnet DC (PMDC) motor. PMDC drive control system has two critical parameters: control and monitoring. Control system includes rotation speed control and direction of rotation of motor using motor drive module BTS7960. The PWM signal has a fixed frequency of waves with varying duty cycles (between 0% and 100%), so the motor rotation can be regulated gradually using a potentiometer already programmed on the Arduino Uno board. The motor rotation direction setting uses the H-bridge circuit method using a 3-way switch to set the direction of forward-reverse rotation of the motor. The monitoring system includes measurements of rotational speed, current, and voltage. Motor rotation speed can be adjusted from the armature voltage settings through the duty cycle PWM setting so that the motor speed can be increased or decreased by the desired duty cycle. From the unload PMDC motor test results it has also been shown that the torque of the motor is relatively constant when there is a change in speed from low rpm to high rpm or vice versa.

  20. Combinatorial Motor Training Results in Functional Reorganization of Remaining Motor Cortex after Controlled Cortical Impact in Rats.

    Science.gov (United States)

    Combs, Hannah L; Jones, Theresa A; Kozlowski, Dorothy A; Adkins, DeAnna L

    2016-04-15

    Cortical reorganization subsequent to post-stroke motor rehabilitative training (RT) has been extensively examined in animal models and humans. However, similar studies focused on the effects of motor training after traumatic brain injury (TBI) are lacking. We previously reported that after a moderate/severe TBI in adult male rats, functional improvements in forelimb use were accomplished only with a combination of skilled forelimb reach training and aerobic exercise, with or without nonimpaired forelimb constraint. Thus, the current study was designed to examine the relationship between functional motor cortical map reorganization after experimental TBI and the behavioral improvements resulting from this combinatorial rehabilitative regime. Adult male rats were trained to proficiency on a skilled reaching task, received a unilateral controlled cortical impact (CCI) over the forelimb area of the caudal motor cortex (CMC). Three days post-CCI, animals began RT (n = 13) or no rehabilitative training (NoRT) control procedures (n = 13). The RT group participated in daily skilled reach training, voluntary aerobic exercise, and nonimpaired forelimb constraint. This RT regimen significantly improved impaired forelimb reaching success and normalized reaching strategies, consistent with previous findings. RT also enlarged the area of motor cortical wrist representation, derived by intracortical microstimulation, compared to NoRT. These findings indicate that sufficient RT can greatly improve motor function and improve the functional integrity of remaining motor cortex after a moderate/severe CCI. When compared with findings from stroke models, these findings also suggest that more intense RT may be needed to improve motor function and remodel the injured cortex after TBI.

  1. Motor Control Abnormalities in Parkinson’s Disease

    Science.gov (United States)

    Mazzoni, Pietro; Shabbott, Britne; Cortés, Juan Camilo

    2012-01-01

    The primary manifestations of Parkinson’s disease are abnormalities of movement, including movement slowness, difficulties with gait and balance, and tremor. We know a considerable amount about the abnormalities of neuronal and muscle activity that correlate with these symptoms. Motor symptoms can also be described in terms of motor control, a level of description that explains how movement variables, such as a limb’s position and speed, are controlled and coordinated. Understanding motor symptoms as motor control abnormalities means to identify how the disease disrupts normal control processes. In the case of Parkinson’s disease, movement slowness, for example, would be explained by a disruption of the control processes that determine normal movement speed. Two long-term benefits of understanding the motor control basis of motor symptoms include the future design of neural prostheses to replace the function of damaged basal ganglia circuits, and the rational design of rehabilitation strategies. This type of understanding, however, remains limited, partly because of limitations in our knowledge of normal motor control. In this article, we review the concept of motor control and describe a few motor symptoms that illustrate the challenges in understanding such symptoms as motor control abnormalities. PMID:22675667

  2. Design of double DC motor control system based on DSP

    Directory of Open Access Journals (Sweden)

    Suo WANG

    2017-10-01

    Full Text Available Aiming at the problems of speed control, commutation and so on in the multi-motor synchronous control system, based on automatic control technology, a control system with PC as principal computer and DSP as slave computer is designed, which can change dual DC motor speed and steering, as well as select work drive motors. Related hardware and software design of the control system are given. Through serial communication between DSP and PC using PC serial port software, digital control command is sent to the slave computer for controlling dual DC motor to do a series of preset functions. PWM pulse width modulation is used for motor speed regulation, photoelectric encoder is used to measure motor speed by T method, and the motor speed is displayed by the actual waveform. Experimental results show that the system can not only realize the synchronization of dual DC motor speed and steering adjustment, but also select the motor and achieve the dual DC motors synchronization control effect. The control system has certain reliability and effectiveness.

  3. Speed Control of Multiphase Cage Induction Motors Incorporating Supply Sequence

    Directory of Open Access Journals (Sweden)

    Drozdowski Piotr

    2014-12-01

    Full Text Available The subject of this paper is the control possibility of the multiphase cage induction motors having number of phases greater than 3. These motors have additional properties for speed control that distinguish them from the standard 3 phase motors: operation at various sequences of supplying voltages due to the inverter control and possible operation with few open-circuited phases. For each supply sequence different no load speeds at the same frequency can be obtained. This feature extends the motor application for miscellaneous drive demands including vector or scalar control. This depends mainly on the type of the stator winding for a given number of phases, since the principle of motor operation is based on co-operation of higher harmonics of magnetic field. Examples of operation are presented for a 9-phase motor, though general approach has been discussed. This motor was fed by a voltage source inverter at field oriented control with forced currents. The mathematical model of the motor was reduced to the form incorporating all most important physical features and appropriate for the control law formulation. The operation was illustrated for various supply sequences for “healthy” motor and for the motor operating at one phase broken. The obtained results have shown that parasitic influence of harmonic fields interaction has negligible influence on motor operation with respect to the useful coupling for properly designed stator winding.

  4. Training leads to increased auditory brain-computer interface performance of end-users with motor impairments.

    Science.gov (United States)

    Halder, S; Käthner, I; Kübler, A

    2016-02-01

    Auditory brain-computer interfaces are an assistive technology that can restore communication for motor impaired end-users. Such non-visual brain-computer interface paradigms are of particular importance for end-users that may lose or have lost gaze control. We attempted to show that motor impaired end-users can learn to control an auditory speller on the basis of event-related potentials. Five end-users with motor impairments, two of whom with additional visual impairments, participated in five sessions. We applied a newly developed auditory brain-computer interface paradigm with natural sounds and directional cues. Three of five end-users learned to select symbols using this method. Averaged over all five end-users the information transfer rate increased by more than 1800% from the first session (0.17 bits/min) to the last session (3.08 bits/min). The two best end-users achieved information transfer rates of 5.78 bits/min and accuracies of 92%. Our results show that an auditory BCI with a combination of natural sounds and directional cues, can be controlled by end-users with motor impairment. Training improves the performance of end-users to the level of healthy controls. To our knowledge, this is the first time end-users with motor impairments controlled an auditory brain-computer interface speller with such high accuracy and information transfer rates. Further, our results demonstrate that operating a BCI with event-related potentials benefits from training and specifically end-users may require more than one session to develop their full potential. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  5. Presentation of electric motor and motor control technology for electric vehicles and hybrid vehicles; Denki jidosha hybrid sha yo motor oyobi motor seigyo gijutsu no shokai

    Energy Technology Data Exchange (ETDEWEB)

    Matsudaira, N.; Masakik, R.; Tajima, F. [Hitachi, Ltd., Tokyo (Japan)

    1999-02-01

    The authors have developed a motor drive system for electric vehicles and hybrid vehicles. This system consists of a permanent magnet type synchronous motor, an inverter using insulated gate bipolar transistors (IGBTs) and a controller based on a single-chip microcomputer. To achieve a compact and light weight synchronous motor, an internal permanent magnet type rotor structure was designed. This paper presents motor control technology for electric vehicles, such as an optimization method of field weakening control and a new current control method. (author)

  6. Motor imagery learning modulates functional connectivity of multiple brain systems in resting state.

    Science.gov (United States)

    Zhang, Hang; Long, Zhiying; Ge, Ruiyang; Xu, Lele; Jin, Zhen; Yao, Li; Liu, Yijun

    2014-01-01

    Learning motor skills involves subsequent modulation of resting-state functional connectivity in the sensory-motor system. This idea was mostly derived from the investigations on motor execution learning which mainly recruits the processing of sensory-motor information. Behavioral evidences demonstrated that motor skills in our daily lives could be learned through imagery procedures. However, it remains unclear whether the modulation of resting-state functional connectivity also exists in the sensory-motor system after motor imagery learning. We performed a fMRI investigation on motor imagery learning from resting state. Based on previous studies, we identified eight sensory and cognitive resting-state networks (RSNs) corresponding to the brain systems and further explored the functional connectivity of these RSNs through the assessments, connectivity and network strengths before and after the two-week consecutive learning. Two intriguing results were revealed: (1) The sensory RSNs, specifically sensory-motor and lateral visual networks exhibited greater connectivity strengths in precuneus and fusiform gyrus after learning; (2) Decreased network strength induced by learning was proved in the default mode network, a cognitive RSN. These results indicated that resting-state functional connectivity could be modulated by motor imagery learning in multiple brain systems, and such modulation displayed in the sensory-motor, visual and default brain systems may be associated with the establishment of motor schema and the regulation of introspective thought. These findings further revealed the neural substrates underlying motor skill learning and potentially provided new insights into the therapeutic benefits of motor imagery learning.

  7. Motor Imagery Learning Modulates Functional Connectivity of Multiple Brain Systems in Resting State

    Science.gov (United States)

    Zhang, Hang; Long, Zhiying; Ge, Ruiyang; Xu, Lele; Jin, Zhen; Yao, Li; Liu, Yijun

    2014-01-01

    Background Learning motor skills involves subsequent modulation of resting-state functional connectivity in the sensory-motor system. This idea was mostly derived from the investigations on motor execution learning which mainly recruits the processing of sensory-motor information. Behavioral evidences demonstrated that motor skills in our daily lives could be learned through imagery procedures. However, it remains unclear whether the modulation of resting-state functional connectivity also exists in the sensory-motor system after motor imagery learning. Methodology/Principal Findings We performed a fMRI investigation on motor imagery learning from resting state. Based on previous studies, we identified eight sensory and cognitive resting-state networks (RSNs) corresponding to the brain systems and further explored the functional connectivity of these RSNs through the assessments, connectivity and network strengths before and after the two-week consecutive learning. Two intriguing results were revealed: (1) The sensory RSNs, specifically sensory-motor and lateral visual networks exhibited greater connectivity strengths in precuneus and fusiform gyrus after learning; (2) Decreased network strength induced by learning was proved in the default mode network, a cognitive RSN. Conclusions/Significance These results indicated that resting-state functional connectivity could be modulated by motor imagery learning in multiple brain systems, and such modulation displayed in the sensory-motor, visual and default brain systems may be associated with the establishment of motor schema and the regulation of introspective thought. These findings further revealed the neural substrates underlying motor skill learning and potentially provided new insights into the therapeutic benefits of motor imagery learning. PMID:24465577

  8. Three-dimensional visualization of functional brain tissue and functional magnetic resonance imaging-integrated neuronavigation in the resection of brain tumor adjacent to motor cortex

    International Nuclear Information System (INIS)

    Han Tong; Cui Shimin; Tong Xiaoguang; Liu Li; Xue Kai; Liu Meili; Liang Siquan; Zhang Yunting; Zhi Dashi

    2011-01-01

    Objective: To assess the value of three -dimensional visualization of functional brain tissue and the functional magnetic resonance imaging (fMRI)-integrated neuronavigation in the resection of brain tumor adjacent to motor cortex. Method: Sixty patients with tumor located in the central sulcus were enrolled. Thirty patients were randomly assigned to function group and 30 to control group. Patients in function group underwent fMRI to localize the functional brain tissues. Then the function information was transferred to the neurosurgical navigator. The patients in control group underwent surgery with navigation without function information. The therapeutic effect, excision rate. improvement of motor function, and survival quality during follow-up were analyzed. Result: All patients in function group were accomplished visualization of functional brain tissues and fMRI-integrated neuronavigation. The locations of tumors, central sulcus and motor cortex were marked during the operation. The fMRI -integrated information played a great role in both pre- and post-operation. Pre-operation: designing the location of the skin flap and window bone, determining the relationship between the tumor and motor cortex, and designing the pathway for the resection. Post- operation: real-time navigation of relationship between the tumor and motor cortex, assisting to localize the motor cortex using interoperation ultra-sound for correcting the displacement by the CSF outflow and collapsing tumor. The patients in the function group had better results than the patients in the control group in therapeutic effect (u=2.646, P=0.008), excision rate (χ = 7.200, P<0.01), improvement of motor function (u=2.231, P=0.026), and survival quality (KPS u c = 2.664, P=0.008; Zubrod -ECOG -WHO u c =2.135, P=0.033). Conclusions: Using preoperative three -dimensional visualization of cerebral function tissue and the fMRI-integrated neuronavigation technology, combining intraoperative accurate

  9. Deep Brain Stimulation in Parkinson’s Disease: New and Emerging Targets for Refractory Motor and Nonmotor Symptoms

    Directory of Open Access Journals (Sweden)

    Dustin Anderson

    2017-01-01

    Full Text Available Parkinson’s disease (PD is a progressive neurodegenerative condition characterized by bradykinesia, tremor, rigidity, and postural instability (PI, in addition to numerous nonmotor manifestations. Many pharmacological therapies now exist to successfully treat PD motor symptoms; however, as the disease progresses, it often becomes challenging to treat with medications alone. Deep brain stimulation (DBS has become a crucial player in PD treatment, particularly for patients who have disabling motor complications from medical treatment. Well-established DBS targets include the subthalamic nucleus (STN, the globus pallidus pars interna (GPi, and to a lesser degree the ventral intermediate nucleus (VIM of the thalamus. Studies of alternative DBS targets for PD are ongoing, the majority of which have shown some clinical benefit; however, more carefully designed and controlled studies are needed. In the present review, we discuss the role of these new and emerging DBS targets in treating refractory axial motor symptoms and other motor and nonmotor symptoms (NMS.

  10. Assessing motor imagery in brain-computer interface training: Psychological and neurophysiological correlates.

    Science.gov (United States)

    Vasilyev, Anatoly; Liburkina, Sofya; Yakovlev, Lev; Perepelkina, Olga; Kaplan, Alexander

    2017-03-01

    Motor imagery (MI) is considered to be a promising cognitive tool for improving motor skills as well as for rehabilitation therapy of movement disorders. It is believed that MI training efficiency could be improved by using the brain-computer interface (BCI) technology providing real-time feedback on person's mental attempts. While BCI is indeed a convenient and motivating tool for practicing MI, it is not clear whether it could be used for predicting or measuring potential positive impact of the training. In this study, we are trying to establish whether the proficiency in BCI control is associated with any of the neurophysiological or psychological correlates of motor imagery, as well as to determine possible interrelations among them. For that purpose, we studied motor imagery in a group of 19 healthy BCI-trained volunteers and performed a correlation analysis across various quantitative assessment metrics. We examined subjects' sensorimotor event-related EEG events, corticospinal excitability changes estimated with single-pulse transcranial magnetic stimulation (TMS), BCI accuracy and self-assessment reports obtained with specially designed questionnaires and interview routine. Our results showed, expectedly, that BCI performance is dependent on the subject's capability to suppress EEG sensorimotor rhythms, which in turn is correlated with the idle state amplitude of those oscillations. Neither BCI accuracy nor the EEG features associated with MI were found to correlate with the level of corticospinal excitability increase during motor imagery, and with assessed imagery vividness. Finally, a significant correlation was found between the level of corticospinal excitability increase and kinesthetic vividness of imagery (KVIQ-20 questionnaire). Our results suggest that two distinct neurophysiological mechanisms might mediate possible effects of motor imagery: the non-specific cortical sensorimotor disinhibition and the focal corticospinal excitability increase

  11. Motor-related brain activity during action observation: a neural substrate for electrocorticographic brain-computer interfaces after spinal cord injury

    Directory of Open Access Journals (Sweden)

    Jennifer L Collinger

    2014-02-01

    Full Text Available After spinal cord injury (SCI, motor commands from the brain are unable to reach peripheral nerves and muscles below the level of the lesion. Action observation, in which a person observes someone else performing an action, has been used to augment traditional rehabilitation paradigms. Similarly, action observation can be used to derive the relationship between brain activity and movement kinematics for a motor-based brain-computer interface (BCI even when the user cannot generate overt movements. BCIs use brain signals to control external devices to replace functions that have been lost due to SCI or other motor impairment. Previous studies have reported congruent motor cortical activity during observed and overt movements using magnetoencephalography (MEG and functional magnetic resonance imaging (fMRI. Recent single-unit studies using intracortical microelectrodes also demonstrated that a large number of motor cortical neurons had similar firing rate patterns between overt and observed movements. Given the increasing interest in electrocorticography (ECoG-based BCIs, our goal was to identify whether action observation-related cortical activity could be recorded using ECoG during grasping tasks. Specifically, we aimed to identify congruent neural activity during observed and executed movements in both the sensorimotor rhythm (10-40 Hz and the high-gamma band (65-115 Hz which contains significant movement-related information. We observed significant motor-related high-gamma band activity during action observation in both able-bodied individuals and one participant with a complete C4 SCI. Furthermore, in able-bodied participants, both the low and high frequency bands demonstrated congruent activity between action execution and observation. Our results suggest that action observation could be an effective and critical procedure for deriving the mapping from ECoG signals to intended movement for an ECoG-based BCI system for individuals with

  12. Reliability of the Motor Learning Strategy Rating Instrument for Children and Youth with Acquired Brain Injury

    Science.gov (United States)

    Kamath, Trishna; Pfeifer, Megan; Banerjee-Guenette, Priyanka; Hunter, Theresa; Ito, Julia; Salbach, Nancy M.; Wright, Virginia; Levac, Danielle

    2012-01-01

    Purpose: To evaluate reliability and feasibility of the Motor Learning Strategy Rating Instrument (MLSRI) in children with acquired brain injury (ABI). The MLSRI quantifies the extent to which motor learning strategies (MLS) are used within physiotherapy (PT) interventions. Methods: PT sessions conducted by ABI team physiotherapists with a…

  13. Short-lived brain state after cued motor imagery in naive subjects

    NARCIS (Netherlands)

    Pfurtscheller, G.; Scherer, R.; Müller-Putz, G.R.; Lopes da Silva, F.H.

    2008-01-01

    Multi-channel electroencephalography recordings have shown that a visual cue, indicating right hand, left hand or foot motor imagery, can induce a short-lived brain state in the order of about 500 ms. In the present study, 10 able-bodied subjects without any motor imagery experience (naive subjects)

  14. Motor Control of Drosophila Courtship Song

    Directory of Open Access Journals (Sweden)

    Troy R. Shirangi

    2013-11-01

    Full Text Available Many animals utilize acoustic signals—or songs—to attract mates. During courtship, Drosophila melanogaster males vibrate a wing to produce trains of pulses and extended tone, called pulse and sine song, respectively. Courtship songs in the genus Drosophila are exceedingly diverse, and different song features appear to have evolved independently of each other. How the nervous system allows such diversity to evolve is not understood. Here, we identify a wing muscle in D. melanogaster (hg1 that is uniquely male-enlarged. The hg1 motoneuron and the sexually dimorphic development of the hg1 muscle are required specifically for the sine component of the male song. In contrast, the motoneuron innervating a sexually monomorphic wing muscle, ps1, is required specifically for a feature of pulse song. Thus, individual wing motor pathways can control separate aspects of courtship song and may provide a “modular” anatomical substrate for the evolution of diverse songs.

  15. ANALISA SISTEM KENDALI PUTARAN MOTOR DC MENGGUNAKAN SILICON CONTROLLED RECTIFIERS

    Directory of Open Access Journals (Sweden)

    M. Khairudin, Efendi, N Purwantiningsih,

    2016-01-01

    Full Text Available ABSTRAK Paper ini bertujuan untuk menganalisa rangkaian sistem kendali putaran motor menggunakan Silicon Controlled Rectifier (SCR atau Thyristor. Eksperimen sistem kendali putaran motor ini menggunakan dua rangkaian yang berbeda. Rangkaian pertama menggunakan dua sumber, yaitu sumber tegangan DC 12 v terhubung dengan motor universal secara seri dengan resistor dan SCR, sedangkan sumber tegangan DC variabel 0 sampai 1.5 v dihubung paralel dengan kapasitor dan resistor. Rangkaian kedua menggunakan satu sumber tegangan AC 5 v yang dihubungkan dengan saklar dan motor. Pada rangkaian kedua ini motor dihubungkan dengan potensio, SCR, dioda serta kapasitor yang dipasang paralel dengan sumber tegangan AC. Hasil eksperimen menunjukkan dalam rangkaian menggunakan sumber tegangan DC, motor DC akan berputar saat saklar S1 tertutup. Kondisi motor akan berputar lebih cepat ketika sumber tegangan variabel diatur lebih besar dari 0 v sehingga arus gate Ig lebih bear dari 400 mA. Adapun Eksperimen dengan sumber tegangan AC, motor akan berputar dengan menambahkan dioda D3 dan pengaturan kecepatan melalui potensio meter Rv sampai posisi maksimum. Kata kunci: analisa, motor DC, SCR, sistem kendali ABSTRACT The objective of this study is to analyse the circuit of DC motor control system using Silicon Controlled Rectifier (SCR or Thyristor. In this experiment the circuit of control system for the motor using two different circuits. The first circuit using two sources, the 12 v DC voltage is connected to universal motor and series with a resistor and SCR, while the DC variable voltage source of 0 to 1.5 v connected in parallel to the capacitor and resistor. The second circuit uses a single source of 5 V AC voltage connected to the switch and the motor. In the second circuit, the motor is connected to the potentio meter, SCR, diode and capacitor in parallel with the AC voltage source. The experimental results showed the circuit using a DC voltage source impacted the

  16. Variable current speed controller for eddy current motors

    Science.gov (United States)

    Gerth, H.L.; Bailey, J.M.; Casstevens, J.M.; Dixon, J.H.; Griffith, B.O.; Igou, R.E.

    1982-03-12

    A speed control system for eddy current motors is provided in which the current to the motor from a constant frequency power source is varied by comparing the actual motor speed signal with a setpoint speed signal to control the motor speed according to the selected setpoint speed. A three-phase variable voltage autotransformer is provided for controlling the voltage from a three-phase power supply. A corresponding plurality of current control resistors is provided in series with each phase of the autotransformer output connected to inputs of a three-phase motor. Each resistor is connected in parallel with a set of normally closed contacts of plurality of relays which are operated by control logic. A logic circuit compares the selected speed with the actual motor speed obtained from a digital tachometer monitoring the motor spindle speed and operated the relays to add or substract resistance equally in each phase of the motor input to vary the motor current to control the motor at the selected speed.

  17. Functional brain correlates of motor response inhibition in children with developmental coordination disorder and attention deficit/hyperactivity disorder.

    Science.gov (United States)

    Thornton, Siobhan; Bray, Signe; Langevin, Lisa Marie; Dewey, Deborah

    2018-06-01

    Motor impairment is associated with developmental coordination disorder (DCD), and to a lesser extent with attention-deficit/hyperactivity disorder (ADHD). Previous functional imaging studies investigated children with DCD or ADHD only; however, these two disorders co-occur in up to 50% of cases, suggesting that similar neural correlates are associated with these disorders. This study compared functional brain activation in children and adolescents (age range 8-17, M = 11.73, SD = 2.88) with DCD (n = 9), ADHD (n = 20), co-occurring DCD and ADHD (n = 18) and typically developing (TD) controls (n = 20). When compared to TD controls, children with co-occurring DCD/ADHD showed decreased activation during response inhibition in primary motor and sensory cortices. These findings suggest that children with co-occurring DCD and ADHD display significant functional changes in brain activation that could interfere with inhibition of erroneous motor responses. In contrast to previous studies, significant alterations in brain activation relative to TD controls, were not found in children with isolated DCD or ADHD. These findings highlight the importance of considering co-occurring disorders when investigating brain function in children with neurodevelopmental disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. From motor cortex to visual cortex: the application of noninvasive brain stimulation to amblyopia.

    Science.gov (United States)

    Thompson, Benjamin; Mansouri, Behzad; Koski, Lisa; Hess, Robert F

    2012-04-01

    Noninvasive brain stimulation is a technique for inducing changes in the excitability of discrete neural populations in the human brain. A current model of the underlying pathological processes contributing to the loss of motor function after stroke has motivated a number of research groups to investigate the potential therapeutic application of brain stimulation to stroke rehabilitation. The loss of motor function is modeled as resulting from a combination of reduced excitability in the lesioned motor cortex and an increased inhibitory drive from the nonlesioned hemisphere over the lesioned hemisphere. This combination of impaired neural function and pathological suppression resonates with current views on the cause of the visual impairment in amblyopia. Here, we discuss how the rationale for using noninvasive brain stimulation in stroke rehabilitation can be applied to amblyopia, review a proof-of-principle study demonstrating that brain stimulation can temporarily improve amblyopic eye function, and propose future research avenues. Copyright © 2010 Wiley Periodicals, Inc.

  19. Neural correlates of learning in an electrocorticographic motor-imagery brain-computer interface

    Science.gov (United States)

    Blakely, Tim M.; Miller, Kai J.; Rao, Rajesh P. N.; Ojemann, Jeffrey G.

    2014-01-01

    Human subjects can learn to control a one-dimensional electrocorticographic (ECoG) brain-computer interface (BCI) using modulation of primary motor (M1) high-gamma activity (signal power in the 75–200 Hz range). However, the stability and dynamics of the signals over the course of new BCI skill acquisition have not been investigated. In this study, we report 3 characteristic periods in evolution of the high-gamma control signal during BCI training: initial, low task accuracy with corresponding low power modulation in the gamma spectrum, followed by a second period of improved task accuracy with increasing average power separation between activity and rest, and a final period of high task accuracy with stable (or decreasing) power separation and decreasing trial-to-trial variance. These findings may have implications in the design and implementation of BCI control algorithms. PMID:25599079

  20. Stepping-Motion Motor-Control Subsystem For Testing Bearings

    Science.gov (United States)

    Powers, Charles E.

    1992-01-01

    Control subsystem closed-loop angular-position-control system causing motor and bearing under test to undergo any of variety of continuous or stepping motions. Also used to test bearing-and-motor assemblies, motors, angular-position sensors including rotating shafts, and like. Monitoring subsystem gathers data used to evaluate performance of bearing or other article under test. Monitoring subsystem described in article, "Monitoring Subsystem For Testing Bearings" (GSC-13432).

  1. Two-dimensional servo control of surface motor; Surface motor no nijigen servo control

    Energy Technology Data Exchange (ETDEWEB)

    Ebihara, D; Takahashi, T; Watada, M [Musashi Institute of Technology, Tokyo (Japan)

    1995-08-20

    Two dimensional (2D) drive system is needed in many aspects of factory automation (FA) and office automation (OA) machines, such as pen drivers in X-Y plotters, X-Y stage for machining, 2D moving robots, etc. Conventional 2D drive systems are consisted from two sets of rotational motor drive and several types of rotary-to-linear transform mechanisms. Linear motors, in these days, have become to be effective as the requirement for high speed increases. We have been studying about Surface Motor which enables 2D drive on a surface by single mover, and the characteristics are measured. Main difficulty of the actuator is that it is short of thrust forces. Also the feasibility is limited because of its vocational uncertainty caused by the open loop control. Our interest is to introduce the closed loop digital control, to obtain required thrust force at any point on the stator. Since open loop control is used, that is, stability point where the thrust force is zero is moved one after another, generated thrust force within the range of synchronization is small. We have been studying about the peculiar expression of exciting currents to generate required direction at all the stator. On the basis of results, two dimensional position feedback system is assembled, which detect the two dimensional location of the mover by optical sensors and direct current instructions are generated for all the four phases of the mover. 14 refs., 11 figs., 1 tab.

  2. Functional Brain Connectivity during Multiple Motor Imagery Tasks in Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Alkinoos Athanasiou

    2018-01-01

    Full Text Available Reciprocal communication of the central and peripheral nervous systems is compromised during spinal cord injury due to neurotrauma of ascending and descending pathways. Changes in brain organization after spinal cord injury have been associated with differences in prognosis. Changes in functional connectivity may also serve as injury biomarkers. Most studies on functional connectivity have focused on chronic complete injury or resting-state condition. In our study, ten right-handed patients with incomplete spinal cord injury and ten age- and gender-matched healthy controls performed multiple visual motor imagery tasks of upper extremities and walking under high-resolution electroencephalography recording. Directed transfer function was used to study connectivity at the cortical source space between sensorimotor nodes. Chronic disruption of reciprocal communication in incomplete injury could result in permanent significant decrease of connectivity in a subset of the sensorimotor network, regardless of positive or negative neurological outcome. Cingulate motor areas consistently contributed the larger outflow (right and received the higher inflow (left among all nodes, across all motor imagery categories, in both groups. Injured subjects had higher outflow from left cingulate than healthy subjects and higher inflow in right cingulate than healthy subjects. Alpha networks were less dense, showing less integration and more segregation than beta networks. Spinal cord injury patients showed signs of increased local processing as adaptive mechanism. This trial is registered with NCT02443558.

  3. Using non-invasive brain stimulation to augment motor training-induced plasticity

    Directory of Open Access Journals (Sweden)

    Pascual-Leone Alvaro

    2009-03-01

    Full Text Available Abstract Therapies for motor recovery after stroke or traumatic brain injury are still not satisfactory. To date the best approach seems to be the intensive physical therapy. However the results are limited and functional gains are often minimal. The goal of motor training is to minimize functional disability and optimize functional motor recovery. This is thought to be achieved by modulation of plastic changes in the brain. Therefore, adjunct interventions that can augment the response of the motor system to the behavioural training might be useful to enhance the therapy-induced recovery in neurological populations. In this context, noninvasive brain stimulation appears to be an interesting option as an add-on intervention to standard physical therapies. Two non-invasive methods of inducing electrical currents into the brain have proved to be promising for inducing long-lasting plastic changes in motor systems: transcranial magnetic stimulation (TMS and transcranial direct current stimulation (tDCS. These techniques represent powerful methods for priming cortical excitability for a subsequent motor task, demand, or stimulation. Thus, their mutual use can optimize the plastic changes induced by motor practice, leading to more remarkable and outlasting clinical gains in rehabilitation. In this review we discuss how these techniques can enhance the effects of a behavioural intervention and the clinical evidence to date.

  4. A Preliminary Comparison of Motor Learning Across Different Non-invasive Brain Stimulation Paradigms Shows No Consistent Modulations

    Directory of Open Access Journals (Sweden)

    Virginia Lopez-Alonso

    2018-04-01

    Full Text Available Non-invasive brain stimulation (NIBS has been widely explored as a way to safely modulate brain activity and alter human performance for nearly three decades. Research using NIBS has grown exponentially within the last decade with promising results across a variety of clinical and healthy populations. However, recent work has shown high inter-individual variability and a lack of reproducibility of previous results. Here, we conducted a small preliminary study to explore the effects of three of the most commonly used excitatory NIBS paradigms over the primary motor cortex (M1 on motor learning (Sequential Visuomotor Isometric Pinch Force Tracking Task and secondarily relate changes in motor learning to changes in cortical excitability (MEP amplitude and SICI. We compared anodal transcranial direct current stimulation (tDCS, paired associative stimulation (PAS25, and intermittent theta burst stimulation (iTBS, along with a sham tDCS control condition. Stimulation was applied prior to motor learning. Participants (n = 28 were randomized into one of the four groups and were trained on a skilled motor task. Motor learning was measured immediately after training (online, 1 day after training (consolidation, and 1 week after training (retention. We did not find consistent differential effects on motor learning or cortical excitability across groups. Within the boundaries of our small sample sizes, we then assessed effect sizes across the NIBS groups that could help power future studies. These results, which require replication with larger samples, are consistent with previous reports of small and variable effect sizes of these interventions on motor learning.

  5. A Preliminary Comparison of Motor Learning Across Different Non-invasive Brain Stimulation Paradigms Shows No Consistent Modulations

    Science.gov (United States)

    Lopez-Alonso, Virginia; Liew, Sook-Lei; Fernández del Olmo, Miguel; Cheeran, Binith; Sandrini, Marco; Abe, Mitsunari; Cohen, Leonardo G.

    2018-01-01

    Non-invasive brain stimulation (NIBS) has been widely explored as a way to safely modulate brain activity and alter human performance for nearly three decades. Research using NIBS has grown exponentially within the last decade with promising results across a variety of clinical and healthy populations. However, recent work has shown high inter-individual variability and a lack of reproducibility of previous results. Here, we conducted a small preliminary study to explore the effects of three of the most commonly used excitatory NIBS paradigms over the primary motor cortex (M1) on motor learning (Sequential Visuomotor Isometric Pinch Force Tracking Task) and secondarily relate changes in motor learning to changes in cortical excitability (MEP amplitude and SICI). We compared anodal transcranial direct current stimulation (tDCS), paired associative stimulation (PAS25), and intermittent theta burst stimulation (iTBS), along with a sham tDCS control condition. Stimulation was applied prior to motor learning. Participants (n = 28) were randomized into one of the four groups and were trained on a skilled motor task. Motor learning was measured immediately after training (online), 1 day after training (consolidation), and 1 week after training (retention). We did not find consistent differential effects on motor learning or cortical excitability across groups. Within the boundaries of our small sample sizes, we then assessed effect sizes across the NIBS groups that could help power future studies. These results, which require replication with larger samples, are consistent with previous reports of small and variable effect sizes of these interventions on motor learning. PMID:29740271

  6. Studies in Motor Behavior: 75 Years of Research in Motor Development, Learning, and Control

    Science.gov (United States)

    Ulrich, Beverly D.; Reeve, T. Gilmour

    2005-01-01

    Research focused on human motor development, learning, and control has been a prominent feature in the Research Quarterly for Exercise and Sport (RQES) since it was first published in 1930. The purpose of this article is to provide an overview of the papers in the RQES that demonstrate the journal's contributions to the study of motor development,…

  7. Controlling chaos in the permanent magnet synchronous motor

    International Nuclear Information System (INIS)

    Zribi, Mohamed; Oteafy, Ahmed; Smaoui, Nejib

    2009-01-01

    The Permanent Magnet Synchronous Motor (PMSM) is known to exhibit chaotic behavior under certain conditions. This paper proposes to use an instantaneous Lyapunov exponent control algorithm to control the PMSM. One of the objectives of the control approach is to bring order to the PMSM and to drive it to any user-defined desired state. Simulation results under different operating conditions indicate that the proposed control scheme works well. Moreover, the proposed Lyapunov exponent control scheme is able to induce chaos on the permanent magnet synchronous motor. Simulation results show the effectiveness of the proposed control scheme in chaotifing the response of the motor.

  8. Design and advanced control of switched reluctance motor; Design og avanceret styring af switched reluctance motor

    Energy Technology Data Exchange (ETDEWEB)

    Blaabjerg, F.; Jensen, F.; Kierkegaard, P.; Pedersen, J.K.; Rasmussen, P.O.; Simonsen, L.

    1999-03-01

    The aim of the project is to design, construct and optimise the control of Switched Reluctance Motors with and without permanent magnets. The expectation was an increased efficiency and a decreased material consumption. The project included originally three types of SR-motors, two with a nominal number of revolutions of 3.000 rpm and one motor with a nominal number of revolutions of 50.000 rpm. The project was changed to focus on one motor with a nominal number of revolutions of 6.000 rpm, one with a nominal number of revolutions of 50.000 rpm and one two-phased low-voltage motor with a nominal number of revolutions of 2.000 rpm. The motors had different outputs of 2,7 kW, 0,9 kW and 3 kW, respectively. For this purpose an advanced simulation programme for Switched Reluctance Motors is developed. The programme differs from other programmes by being able to simulate multi-disciplinary such as vibrations and acoustic noise. It is even possible to play the sound. In this connection completely new models are developed. It is also possible to simulate different grid connected converters. Input to the simulation programme is finite element calculations, geometry of the motor and calculations or data from an advanced characterisation system for Switched Reluctance Motors. New methods to control the current in Switched Reluctance Motors are developed, which particularly make quick dynamics possible in a digitally controlled current without use of special noise filters. The method will soon have industrial use. Other new methods have emerged, which secure that the system all the time works with the maximum efficiency irrespective of load. In some cases an efficiency improvement of 10 % is obtained compared to a classic control of the Switched Reluctance Motor. (EHS) EFP-94; EFP-95; EFP-98. 16 refs.

  9. Controlling An Inverter-Driven Three-Phase Motor

    Science.gov (United States)

    Dolland, C.

    1984-01-01

    Control system for three-phase permanent-magnet motor driven by linecommutated inverter uses signals generated by integrating back emf of each phase of motor. High-pass filter network eliminates low-frequency components from control loop while maintaining desired power factor.

  10. 78 FR 32223 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards

    Science.gov (United States)

    2013-05-29

    ...-OAR-2011-0135; FRL-9818-5] RIN 2060-A0 Control of Air Pollution From Motor Vehicles: Tier 3 Motor... extension of the public comment period for the proposed rule ``Control of Air Pollution from Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards'' (the proposed rule is hereinafter referred to as...

  11. Tetrahydrobiopterin in antenatal brain hypoxia-ischemia-induced motor impairments and cerebral palsy.

    Science.gov (United States)

    Vasquez-Vivar, Jeannette; Shi, Zhongjie; Luo, Kehuan; Thirugnanam, Karthikeyan; Tan, Sidhartha

    2017-10-01

    Antenatal brain hypoxia-ischemia, which occurs in cerebral palsy, is considered a significant cause of motor impairments in children. The mechanisms by which antenatal hypoxia-ischemia causes brain injury and motor deficits still need to be elucidated. Tetrahydrobiopterin is an important enzyme cofactor that is necessary to produce neurotransmitters and to maintain the redox status of the brain. A genetic deficiency of this cofactor from mutations of biosynthetic or recycling enzymes is a well-recognized factor in the development of childhood neurological disorders characterized by motor impairments, developmental delay, and encephalopathy. Experimental hypoxia-ischemia causes a decline in the availability of tetrahydrobiopterin in the immature brain. This decline coincides with the loss of brain function, suggesting this occurrence contributes to neuronal dysfunction and motor impairments. One possible mechanism linking tetrahydrobiopterin deficiency, hypoxia-ischemia, and neuronal injury is oxidative injury. Evidence of the central role of the developmental biology of tetrahydrobiopterin in response to hypoxic ischemic brain injury, especially the development of motor deficits, is discussed. Copyright © 2017. Published by Elsevier B.V.

  12. Physiological basis and image processing in functional magnetic resonance imaging: Neuronal and motor activity in brain

    Directory of Open Access Journals (Sweden)

    Sharma Rakesh

    2004-05-01

    Full Text Available Abstract Functional magnetic resonance imaging (fMRI is recently developing as imaging modality used for mapping hemodynamics of neuronal and motor event related tissue blood oxygen level dependence (BOLD in terms of brain activation. Image processing is performed by segmentation and registration methods. Segmentation algorithms provide brain surface-based analysis, automated anatomical labeling of cortical fields in magnetic resonance data sets based on oxygen metabolic state. Registration algorithms provide geometric features using two or more imaging modalities to assure clinically useful neuronal and motor information of brain activation. This review article summarizes the physiological basis of fMRI signal, its origin, contrast enhancement, physical factors, anatomical labeling by segmentation, registration approaches with examples of visual and motor activity in brain. Latest developments are reviewed for clinical applications of fMRI along with other different neurophysiological and imaging modalities.

  13. Design of dual DC motor control system based on DSP

    Science.gov (United States)

    Shi, Peicheng; Wang, Suo; Xu, Zengwei; Xiao, Ping

    2017-08-01

    Multi-motor control systems are widely used in actual production and life, such as lifting stages, robots, printing systems. This paper through serial communication between PC and DSP, dual DC motor control system consisting of PC as the host computer, DSP as the lower computer with synchronous PWM speed regulation, commutation and selection functions is designed. It sends digital control instructions with host computer serial debugger to lower computer, to instruct the motor to complete corresponding actions. The hardware and software design of the control system are given, and feasibility and validity of the control system are verified by experiments. The expected design goal is achieved.

  14. AC electric motors control advanced design techniques and applications

    CERN Document Server

    Giri, Fouad

    2013-01-01

    The complexity of AC motor control lies in the multivariable and nonlinear nature of AC machine dynamics. Recent advancements in control theory now make it possible to deal with long-standing problems in AC motors control. This text expertly draws on these developments to apply a wide range of model-based control designmethods to a variety of AC motors. Contributions from over thirty top researchers explain how modern control design methods can be used to achieve tight speed regulation, optimal energetic efficiency, and operation reliability and safety, by considering online state var

  15. Analysis of neural activity in human motor cortex -- Towards brain machine interface system

    Science.gov (United States)

    Secundo, Lavi

    The discovery of directional tuned neurons in the primary motor cortex has advanced motor research in several domains. For instance, in the area of brain machine interface (BMI), researchers have exploited the robust characteristic of tuned motor neurons to allow monkeys to learn control of various machines. In the first chapter of this work we examine whether this phenomena can be observed using the less invasive method of recording electrocorticographic signals (ECoG) from the surface of a human's brain. Our findings reveal that individual ECoG channels contain complex movement information about the neuronal population. While some ECoG channels are tuned to hand movement direction (direction specific channels), others are associated to movement but do not contain information regarding movement direction (non-direction specific channels). More specifically, directionality can vary temporally and by frequency within one channel. In addition, a handful of channels contain no significant information regarding movement at all. These findings strongly suggest that directional and non-directional regions of cortex can be identified with ECoG and provide solutions to decoding movement at the signal resolution provided by ECoG. In the second chapter we examine the influence of movement context on movement reconstruction accuracy. We recorded neuronal signals recorded from electro-corticography (ECoG) during performance of cued- and self-initiated movements. ECoG signals were used to train a reconstruction algorithm to reconstruct continuous hand movement. We found that both cued- and self-initiated movements could be reconstructed with similar accuracy from the ECoG data. However, while an algorithm trained on the cued task could reconstruct performance on a subsequent cued trial, it failed to reconstruct self-initiated arm movement. The same task-specificity was observed when the algorithm was trained with self-initiated movement data and tested on the cued task. Thus

  16. DC motor proportional control system for orthotic devices

    Science.gov (United States)

    Blaise, H. T.; Allen, J. R.

    1972-01-01

    Multi-channel proportional control system for operation of dc motors for use with externally-powered orthotic arm braces is described. Components of circuitry and principles of operation are described. Schematic diagram of control circuit is provided.

  17. [Local brain activity in different motor subtypes of Parkinson's disease with fMRI].

    Science.gov (United States)

    Hou, Ya'nan; Zhang, Jiarong; Chen, Biao; Wu, Tao

    2015-02-17

    To explore the changes of local brain activity in motor subtypes of Parkinson's disease (PD) with functional magnetic resonance imaging (fMRI). A total of 60 idiopathic PD and 30 age- and gender-matched normal controls were examined with resting-state fMRI from January 2013 to March 2014. All subjects gave their written informed consent for the study. The amplitude of low-frequency fluctuation (ALFF) was calculated to measure local brain activity. The PD patients were divided into two groups of tremor dominant (TD) and postural instability/gait difficulty (PIGD) (n = 30 each). All subjects gave their written in formed consent for the study.One-way ANOVA and post-hoc t-test were performed to detect the differences of local brain activity between PD and normal subjects. And the correlations were examined between ALFF, scores and levodopa dose. Compared with normal subjects, the TD group showed increased activity in bilateral cerebellums (-37, -47, -38), thalamus (-18, -17,0), pons (-3, -23, -37) and left precentral gyrus (-41, -30, 46) versus decreased activity in bilateral frontal lobes (-13, 69, 6), temporal lobes (-42, 18, -21), left insula (-32, 22, 2) and left anterior cingulated (-7, 32, -5). The PIGD group showed increased activity in right postcentral gyrus (63, -18, 39) and decreased activity in bilateral putamens (-24, 12, 3), pre-supplementary motor area (10, 10, 58), frontal lobes (15, -15, 57), temporal lobes (-39, 18, -3) and left insula (-29, 20, 11). Compared with PIGD, the TD group showed increased activity in temporal lobes, but decreased activity in frontal lobes. Additionally, ALFF in bilateral cerebellums and frontal lobes was positively correlated with TD scores while ALFF in left precentral gyrus, bilateral putamens and temporal lobes negatively correlated with TD scores. ALFF in bilateral frontal lobes and left temporal lobe was positively correlated with PIGD scores.However, in right postcentral gyrus and bilateral putamens, ALFF was

  18. Control Of Stepper Motor Movement By DC Voltage

    International Nuclear Information System (INIS)

    Gayani, Didi; Margono; Indasah, Iin; Sugito

    2000-01-01

    Instrumentation for controlling the power of reactor of TRIGA Mark II uses the stepper motor to move the control rod of neutron absorbers. The direction and speed of control rod movement are determined by the polarity and the amplitude of DC voltage as an error signal that is the difference of set point of power and the power of being measured on the control system. The unit of stepper motor controller of reactor instrumentation of TRIGA Mark II uses patent module of trade Mark of Vexta, USA. In this chance, the electronic circuit is made to function as the control of stepper motor movement by using the DC voltage to anticipate the problem may be faced in case of repair and maintenance of reactor instrumentation. As a result of experiment, it is stated that the control of motor movement by using DC voltage is performed into 2 stages. First, by making the oscillator that is proportional to the positive DC voltage. Secondly, by making the translator to translate the oscillator signal to be a logic pattern for controlling the movement of stepper motor. Translator and motor driver are made by using the L297 and L298 as a pair of stepper motor controller of SGS T HOMSON

  19. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation.

    Science.gov (United States)

    Wallentin, Mikkel; Skakkebæk, Anne; Bojesen, Anders; Fedder, Jens; Laurberg, Peter; Østergaard, John R; Hertz, Jens Michael; Pedersen, Anders Degn; Gravholt, Claus Højbjerg

    2016-01-01

    Klinefelter syndrome (47, XXY) (KS) is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49) responded to whether the words "GREEN" or "RED" were displayed in green or red (incongruent versus congruent colors). One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying "GREEN" or "RED" had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop) or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system.

  20. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation

    Directory of Open Access Journals (Sweden)

    Mikkel Wallentin

    2016-01-01

    Full Text Available Klinefelter syndrome (47, XXY (KS is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49 responded to whether the words “GREEN” or “RED” were displayed in green or red (incongruent versus congruent colors. One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying “GREEN” or “RED” had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system.

  1. Brain changes following four weeks of unimanual motor training: Evidence from behavior, neural stimulation, cortical thickness, and functional MRI.

    Science.gov (United States)

    Sale, Martin V; Reid, Lee B; Cocchi, Luca; Pagnozzi, Alex M; Rose, Stephen E; Mattingley, Jason B

    2017-09-01

    Although different aspects of neuroplasticity can be quantified with behavioral probes, brain stimulation, and brain imaging assessments, no study to date has combined all these approaches into one comprehensive assessment of brain plasticity. Here, 24 healthy right-handed participants practiced a sequence of finger-thumb opposition movements for 10 min each day with their left hand. After 4 weeks, performance for the practiced sequence improved significantly (P left (mean increase: 53.0% practiced, 6.5% control) and right (21.0%; 15.8%) hands. Training also induced significant (cluster p-FWE right hemisphere, 301 voxel cluster; left hemisphere 700 voxel cluster), and sensorimotor cortices and superior parietal lobules (right hemisphere 864 voxel cluster; left hemisphere, 1947 voxel cluster). Transcranial magnetic stimulation over the right ("trained") primary motor cortex yielded a 58.6% mean increase in a measure of motor evoked potential amplitude, as recorded at the left abductor pollicis brevis muscle. Cortical thickness analyses based on structural MRI suggested changes in the right precentral gyrus, right post central gyrus, right dorsolateral prefrontal cortex, and potentially the right supplementary motor area. Such findings are consistent with LTP-like neuroplastic changes in areas that were already responsible for finger sequence execution, rather than improved recruitment of previously nonutilized tissue. Hum Brain Mapp 38:4773-4787, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  2. Sensorless Sliding Mode Vector Control of Induction Motor Drives

    OpenAIRE

    Gouichiche Abdelmadjid; Boucherit Mohamed Seghir; Safa Ahmed; Messlem Youcef

    2012-01-01

    In this paper we present the design of sliding mode controllers for sensorless field oriented control of induction motor. In order to improve the performance of controllers, the motor speed is controlled by sliding mode regulator with integral sliding surface. The estimated rotor speed used in speed feedback loop is calculated by an adaptive observer based on MRAS (model reference adaptive system) technique .the validity of the proposed scheme is demonstrated by experimental results.

  3. Brain activation in motor sequence learning is related to the level of native cortical excitability.

    Directory of Open Access Journals (Sweden)

    Silke Lissek

    Full Text Available Cortical excitability may be subject to changes through training and learning. Motor training can increase cortical excitability in motor cortex, and facilitation of motor cortical excitability has been shown to be positively correlated with improvements in performance in simple motor tasks. Thus cortical excitability may tentatively be considered as a marker of learning and use-dependent plasticity. Previous studies focused on changes in cortical excitability brought about by learning processes, however, the relation between native levels of cortical excitability on the one hand and brain activation and behavioral parameters on the other is as yet unknown. In the present study we investigated the role of differential native motor cortical excitability for learning a motor sequencing task with regard to post-training changes in excitability, behavioral performance and involvement of brain regions. Our motor task required our participants to reproduce and improvise over a pre-learned motor sequence. Over both task conditions, participants with low cortical excitability (CElo showed significantly higher BOLD activation in task-relevant brain regions than participants with high cortical excitability (CEhi. In contrast, CElo and CEhi groups did not exhibit differences in percentage of correct responses and improvisation level. Moreover, cortical excitability did not change significantly after learning and training in either group, with the exception of a significant decrease in facilitatory excitability in the CEhi group. The present data suggest that the native, unmanipulated level of cortical excitability is related to brain activation intensity, but not to performance quality. The higher BOLD mean signal intensity during the motor task might reflect a compensatory mechanism in CElo participants.

  4. Sensorless Control of PM Synchronous Motors and Brushless DC Motors

    DEFF Research Database (Denmark)

    Montesinos, D.; Galceran, Samuel; Blaabjerg, Frede

    2005-01-01

    This paper provides a review of the literature addressing sensorless operation methods of PM brushless machines. The methods explained are state-of-the-art of open and closed loop control strategies. The closed loop review includes those methods based on voltage and current measurements, those me...

  5. Clinical evaluation of BrainTree, a motor imagery hybrid BCI speller

    Science.gov (United States)

    Perdikis, S.; Leeb, R.; Williamson, J.; Ramsay, A.; Tavella, M.; Desideri, L.; Hoogerwerf, E.-J.; Al-Khodairy, A.; Murray-Smith, R.; Millán, J. d. R.

    2014-06-01

    Objective. While brain-computer interfaces (BCIs) for communication have reached considerable technical maturity, there is still a great need for state-of-the-art evaluation by the end-users outside laboratory environments. To achieve this primary objective, it is necessary to augment a BCI with a series of components that allow end-users to type text effectively. Approach. This work presents the clinical evaluation of a motor imagery (MI) BCI text-speller, called BrainTree, by six severely disabled end-users and ten able-bodied users. Additionally, we define a generic model of code-based BCI applications, which serves as an analytical tool for evaluation and design. Main results. We show that all users achieved remarkable usability and efficiency outcomes in spelling. Furthermore, our model-based analysis highlights the added value of human-computer interaction techniques and hybrid BCI error-handling mechanisms, and reveals the effects of BCI performances on usability and efficiency in code-based applications. Significance. This study demonstrates the usability potential of code-based MI spellers, with BrainTree being the first to be evaluated by a substantial number of end-users, establishing them as a viable, competitive alternative to other popular BCI spellers. Another major outcome of our model-based analysis is the derivation of a 80% minimum command accuracy requirement for successful code-based application control, revising upwards previous estimates attempted in the literature.

  6. PID controller simulator software for DC motor of gamma scanning

    International Nuclear Information System (INIS)

    Arjoni Amir

    2008-01-01

    Mostly PID controller (Proportional-Integral-Derivative) has been used in industry. For certain applications, it can be used as a Proportional (P) model only, or as a Proportional-Integral (PI) model. The aim of this paper is to design a PID controller simulator software for DC motor which is used in gamma scanning system. A DC motor is described as a plant of SISO (Single Input Single Output) which is used for pulling down the load (detector + casing) and gamma radiation source (Co-60 + container) by using sling cable. A DC motor consist of an armature and a rotor, the equivalent circuit of DC motor is shown in a transfer function equation between output parameter (angular speed DC motor) and input parameter (voltage of DC motor). Methods used for the process of PID controller design is to arrange the PID controller parameter (Kc, Ti, Td) so that there are more PID controller transfer function model which are able to control angular speed of DC motor in stable condition, as design criteria requirement is needed. Design criteria requirement for control system are the settling time < 3 second, overshoot < 5%, rise time = 0.25 second, steady state gain = 1 and peak time < 3 second with step response reference 1 rad/second. The result of simulation gives several models of PID controller in function transfer equation which is similar with design criteria requirement in a equation of function transfer of order 2 for numerator and order 1 for denominator. (author)

  7. Contribution of transcranial magnetic stimulation to the understanding of cortical mechanisms involved in motor control.

    Science.gov (United States)

    Reis, Janine; Swayne, Orlando B; Vandermeeren, Yves; Camus, Mickael; Dimyan, Michael A; Harris-Love, Michelle; Perez, Monica A; Ragert, Patrick; Rothwell, John C; Cohen, Leonardo G

    2008-01-15

    Transcranial magnetic stimulation (TMS) was initially used to evaluate the integrity of the corticospinal tract in humans non-invasively. Since these early studies, the development of paired-pulse and repetitive TMS protocols allowed investigators to explore inhibitory and excitatory interactions of various motor and non-motor cortical regions within and across cerebral hemispheres. These applications have provided insight into the intracortical physiological processes underlying the functional role of different brain regions in various cognitive processes, motor control in health and disease and neuroplastic changes during recovery of function after brain lesions. Used in combination with neuroimaging tools, TMS provides valuable information on functional connectivity between different brain regions, and on the relationship between physiological processes and the anatomical configuration of specific brain areas and connected pathways. More recently, there has been increasing interest in the extent to which these physiological processes are modulated depending on the behavioural setting. The purpose of this paper is (a) to present an up-to-date review of the available electrophysiological data and the impact on our understanding of human motor behaviour and (b) to discuss some of the gaps in our present knowledge as well as future directions of research in a format accessible to new students and/or investigators. Finally, areas of uncertainty and limitations in the interpretation of TMS studies are discussed in some detail.

  8. The amygdalo-motor pathway and the control of facial expressions

    Directory of Open Access Journals (Sweden)

    Katalin M Gothard

    2014-03-01

    Full Text Available Facial expressions reflect decisions about the perceived meaning of social stimuli emitted by others and the expected socio-emotional outcome of the reciprocating expression. The decision to produce a facial expression emerges from the joint activity of a network of structures that include the amygdala and multiple, interconnected cortical and subcortical motor areas. Reciprocal transformations between sensory and motor signals give rise to distinct brain states that promote, or impede the production of facial expressions. The muscles of the upper and lower face are controlled by anatomically distinct motor areas and thus require distinct patterns of motor commands. Concomitantly multiple areas, including the amygdala, monitor the ongoing overt behavior (the expression of self and the covert, autonomic responses that accompany emotional expressions. Interoceptive signals and visceral states, therefore, should be incorporated into the formalisms of decision making in order account for decisions that govern the receiving-emitting cycle of facial expressions.

  9. Distinct brain metabolic patterns separately associated with cognition, motor function, and aging in Parkinson's disease dementia.

    Science.gov (United States)

    Ko, Ji Hyun; Katako, Audrey; Aljuaid, Maram; Goertzen, Andrew L; Borys, Andrew; Hobson, Douglas E; Kim, Seok Min; Lee, Chong Sik

    2017-12-01

    We explored whether patients with Parkinson's disease dementia (PDD) show a distinct spatial metabolic pattern that characterizes cognitive deficits in addition to motor dysfunction. Eighteen patients with PDD underwent 3 separate positron emission tomography sessions with [ 18 F]fluorodeoxyglucose (for glucose metabolism), fluorinated N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane (for dopamine transporter density) and Pittsburgh compound-B (for beta-amyloid load). We confirmed in PDD versus normal controls, overall hypometabolism in the posterior and prefrontal brain regions accompanied with hypermetabolism in subcortical structures and the cerebellar vermis. A multivariate network analysis then revealed 3 metabolic patterns that are separately associated with cognitive performance (p = 0.042), age (p = 0.042), and motor symptom severity (p = 0.039). The age-related pattern's association with aging was replicated in healthy controls (p = 0.047) and patients with Alzheimer's disease (p = 0.002). The cognition-related pattern's association with cognitive performance was observed, with a trend-level of correlation, in patients with dementia with Lewy bodies (p = 0.084) but not in patients with Alzheimer's disease (p = 0.974). We found no association with fluorinated N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane and Pittsburgh compound-B positron emission tomography with patients' cognitive performance. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Quad-copter UAV BLDC Motor Control: Linear v/s non-linear control maps

    Directory of Open Access Journals (Sweden)

    Deep Parikh

    2015-08-01

    Full Text Available This paper presents some investigations and comparison of using linear versus non-linear static motor-control maps for the speed control of a BLDC (Brush Less Direct Current motors used in quad-copter UAV (Unmanned Aerial Vehicles. The motor-control map considered here is the inverse of the static map relating motor-speed output to motor-voltage input for a typical out-runner type Brushless DC Motors (BLDCM.  Traditionally, quad-copter BLDC motor speed control uses simple linear motor-control map defined by the motor-constant specification. However, practical BLDC motors show non-linear characteristic, particularly when operated across wide operating speed-range as is commonly required in quad-copter UAV flight operations. In this paper, our investigations to compare performance of linear versus non-linear motor-control maps are presented. The investigations cover simulation-based and experimental study of BLDC motor speed control systems for  quad-copter vehicle available. First the non-linear map relating rotor RPM to motor voltage for quad-copter BLDC motor is obtained experimentally using an optical speed encoder. The performance of the linear versus non-linear motor-control-maps for the speed control are studied. The investigations also cover study of time-responses for various standard test input-signals e.g. step, ramp and pulse inputs, applied as the reference speed-commands. Also, simple 2-degree of freedom test-bed is developed in our laboratory to help test the open-loop and closed-loop experimental investigations. The non-linear motor-control map is found to perform better in BLDC motor speed tracking control performance and thereby helping achieve better quad-copter roll-angle attitude control.

  11. performance characteristics of an armature voltage controlled dc motor

    African Journals Online (AJOL)

    Dr Obe

    . INTRODUCTION. The good control properties of the d.c. motor have made possible its initial large scale application in industry [1]. In spite of the present superiority of the solid state squirrel cage induction motor drive, especially at supply ...

  12. A brushless dc spin motor for momentum exchange altitude control

    Science.gov (United States)

    Stern, D.; Rosenlieb, J. W.

    1972-01-01

    Brushless dc spin motor is designed to use Hall effect probes as means of revolving rotor position and controlling motor winding currents. This results in 3 to 1 reduction in watt-hours required for wheel acceleration, a 2 to 1 reduction in power to run wheel, and a 10 to 1 reduction in the electronics size and weight.

  13. Control Systems Lab Using a LEGO Mindstorms NXT Motor System

    Science.gov (United States)

    Kim, Y.

    2011-01-01

    This paper introduces a low-cost LEGO Mindstorms NXT motor system for teaching classical and modern control theories in standard third-year undergraduate courses. The LEGO motor system can be used in conjunction with MATLAB, Simulink, and several necessary toolboxes to demonstrate: 1) a modeling technique; 2) proportional-integral-differential…

  14. Discrete-Time LPV Current Control of an Induction Motor

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, Klaus

    2001-01-01

    In this paper we apply a new method for gain-scheduled output feedback control of nonlinear systems to current control of an induction motor. The method relies on recently developed controller synthesis results for linear parameter-varying (LPV) systems, where the controller synthesis is formulated...... without further complications. The synthesis method is applied to the model, yielding an LPV discrete-time controller. Finally, the efficiency of the control scheme is validated via simulations as well as experimentally on the actual induction motor, both in open-loop current control and when an outer...... speed control loop is closed around the current loop...

  15. Discrete-Time LPV Current Control of an Induction Motor

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, Klaus

    2003-01-01

    In this paper we apply a new method for gain-scheduled output feedback control of nonlinear systems to current control of an induction motor. The method relies on recently developed controller synthesis results for linear parameter-varying (LPV) systems, where the controller synthesis is formulated...... further complications. The synthesis method is applied to the model, yielding an LPV discrete-time controller. Finally, the efficiency of the control scheme is validated via simulations as well as on the actual induction motor, both in open-loop current control and when an outer speed control loop...... is closed around the current loop....

  16. Self-Control and the Developing Brain

    Science.gov (United States)

    Tarullo, Amanda R.; Obradovic, Jelena; Gunnar, Megan R.

    2009-01-01

    Self-control is a skill that children need to succeed academically, socially, and emotionally. Brain regions essential to self-control are immature at birth and develop slowly throughout childhood. From ages 3 to 6 years, as these brain regions become more mature, children show improved ability to control impulses, shift their attention flexibly,…

  17. Switch Reluctance Motor Control Based on Fuzzy Logic System

    Directory of Open Access Journals (Sweden)

    S. V. Aleksandrovsky

    2012-01-01

    Full Text Available Due to its intrinsic simplicity and reliability, the switched reluctance motor (SRM has now become a promising candidate for variable-speed drive applications as an alternative induction motor in various industrial application. However, the SRM has the disadvantage of nonlinear characteristic and control. It is suggested to use controller based on fuzzy logic system. Design of FLS controller and simulation model presented.

  18. Fuzzy adaptive speed control of a permanent magnet synchronous motor

    Science.gov (United States)

    Choi, Han Ho; Jung, Jin-Woo; Kim, Rae-Young

    2012-05-01

    A fuzzy adaptive speed controller is proposed for a permanent magnet synchronous motor (PMSM). The proposed fuzzy adaptive speed regulator is insensitive to model parameter and load torque variations because it does not need any accurate knowledge about the motor parameter and load torque values. The stability of the proposed control system is also proven. The proposed adaptive speed regulator system is implemented by using a TMS320F28335 floating point DSP. Simulation and experimental results are presented to verify the effectiveness of the proposed fuzzy adaptive speed controller under uncertainties such as motor parameter and load torque variations using a prototype PMSM drive system.

  19. Hierarchical control of motor units in voluntary contractions.

    Science.gov (United States)

    De Luca, Carlo J; Contessa, Paola

    2012-01-01

    For the past five decades there has been wide acceptance of a relationship between the firing rate of motor units and the afterhyperpolarization of motoneurons. It has been promulgated that the higher-threshold, larger-soma, motoneurons fire faster than the lower-threshold, smaller-soma, motor units. This relationship was based on studies on anesthetized cats with electrically stimulated motoneurons. We questioned its applicability to motor unit control during voluntary contractions in humans. We found that during linearly force-increasing contractions, firing rates increased as exponential functions. At any time and force level, including at recruitment, the firing rate values were inversely related to the recruitment threshold of the motor unit. The time constants of the exponential functions were directly related to the recruitment threshold. From the Henneman size principle it follows that the characteristics of the firing rates are also related to the size of the soma. The "firing rate spectrum" presents a beautifully simple control scheme in which, at any given time or force, the firing rate value of earlier-recruited motor units is greater than that of later-recruited motor units. This hierarchical control scheme describes a mechanism that provides an effective economy of force generation for the earlier-recruited lower force-twitch motor units, and reduces the fatigue of later-recruited higher force-twitch motor units-both characteristics being well suited for generating and sustaining force during the fight-or-flight response.

  20. Evolution of Motor Control: From Reflexes and Motor Programs to the Equilibrium-Point Hypothesis.

    Science.gov (United States)

    Latash, Mark L

    2008-01-01

    This brief review analyzes the evolution of motor control theories along two lines that emphasize active (motor programs) and reactive (reflexes) features of voluntary movements. It suggests that the only contemporary hypothesis that integrates both approaches in a fruitful way is the equilibrium-point hypothesis. Physical, physiological, and behavioral foundations of the EP-hypothesis are considered as well as relations between the EP-hypothesis and the recent developments of the notion of motor synergies. The paper ends with a brief review of the criticisms of the EP-hypothesis and challenges that the hypothesis faces at this time.

  1. Effect of Obesity on Motor Functional Outcome of Rehabilitating Traumatic Brain Injury Patients.

    Science.gov (United States)

    Le, David; Shafi, Shahid; Gwirtz, Patricia; Bennett, Monica; Reeves, Rustin; Callender, Librada; Dunklin, Cynthia; Cleveland, Samantha

    2015-08-01

    The aim of this study was to determine the association between obesity and functional motor outcome of patients undergoing inpatient rehabilitation after traumatic brain injury. This retrospective study at an urban acute inpatient rehabilitation center screened data from 761 subjects in the Traumatic Brain Injury Model System who were admitted from January 2010 to September 2013. Inclusion criteria consisted of age of 18 years or older and an abnormal Functional Independence Measure motor score. Body mass index was used to determine obesity in the study population. Patients with a body mass index of 30.0 kg/m or greater were considered obese. A total of 372 subjects met the criteria for inclusion in the study. Of these, 54 (13.2%) were obese. Both obese and nonobese patients showed similar improvement in Functional Independence Measure motor score (mean [SD], 30.4 [12.8] for the obese patients, P = 0.115, and 27.3 [13.1] for the nonobese patients). The mean (SD) Functional Independence Measure motor scores at discharge for the obese and nonobese patients were 63.0 (12.6) and 62.3 (10.1) (P = 0.6548), respectively. Obesity had no adverse impact on motor functional outcomes of the traumatic brain injury patients who underwent inpatient rehabilitation. Therefore, obesity should not be considered an obstacle in inpatient rehabilitation after traumatic brain injury, if patients are able to participate in necessary therapy.

  2. Discrete-Time LPV Current Control of an Induction Motor

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, Klaus

    2003-01-01

    In this paper we apply a new method for gain-scheduled output feedback control of nonlinear systems to current control of an induction motor. The method relies on recently developed controller synthesis results for linear parameter-varying (LPV) systems, where the controller synthesis is formulated...... as a set of linear matrix inequalities with full-block multipliers. A standard nonlinear model of the motor is constructed and written on LPV form. We then show that, although originally developed in continuous time, the controller synthesis results can be applied to a discrete-time model as well without...... further complications. The synthesis method is applied to the model, yielding an LPV discrete-time controller. Finally, the efficiency of the control scheme is validated via simulations as well as on the actual induction motor, both in open-loop current control and when an outer speed control loop...

  3. Combined rTMS and virtual reality brain-computer interface training for motor recovery after stroke

    Science.gov (United States)

    Johnson, N. N.; Carey, J.; Edelman, B. J.; Doud, A.; Grande, A.; Lakshminarayan, K.; He, B.

    2018-02-01

    Objective. Combining repetitive transcranial magnetic stimulation (rTMS) with brain-computer interface (BCI) training can address motor impairment after stroke by down-regulating exaggerated inhibition from the contralesional hemisphere and encouraging ipsilesional activation. The objective was to evaluate the efficacy of combined rTMS  +  BCI, compared to sham rTMS  +  BCI, on motor recovery after stroke in subjects with lasting motor paresis. Approach. Three stroke subjects approximately one year post-stroke participated in three weeks of combined rTMS (real or sham) and BCI, followed by three weeks of BCI alone. Behavioral and electrophysiological differences were evaluated at baseline, after three weeks, and after six weeks of treatment. Main results. Motor improvements were observed in both real rTMS  +  BCI and sham groups, but only the former showed significant alterations in inter-hemispheric inhibition in the desired direction and increased relative ipsilesional cortical activation from fMRI. In addition, significant improvements in BCI performance over time and adequate control of the virtual reality BCI paradigm were observed only in the former group. Significance. When combined, the results highlight the feasibility and efficacy of combined rTMS  +  BCI for motor recovery, demonstrated by increased ipsilesional motor activity and improvements in behavioral function for the real rTMS  +  BCI condition in particular. Our findings also demonstrate the utility of BCI training alone, as shown by behavioral improvements for the sham rTMS  +  BCI condition. This study is the first to evaluate combined rTMS and BCI training for motor rehabilitation and provides a foundation for continued work to evaluate the potential of both rTMS and virtual reality BCI training for motor recovery after stroke.

  4. Evolution of Motor Control: From Reflexes and Motor Programs to the Equilibrium-Point Hypothesis

    OpenAIRE

    Latash, Mark L.

    2008-01-01

    This brief review analyzes the evolution of motor control theories along two lines that emphasize active (motor programs) and reactive (reflexes) features of voluntary movements. It suggests that the only contemporary hypothesis that integrates both approaches in a fruitful way is the equilibrium-point hypothesis. Physical, physiological, and behavioral foundations of the EP-hypothesis are considered as well as relations between the EP-hypothesis and the recent developments of the notion of m...

  5. Maturation of Sensori-Motor Functional Responses in the Preterm Brain.

    Science.gov (United States)

    Allievi, Alessandro G; Arichi, Tomoki; Tusor, Nora; Kimpton, Jessica; Arulkumaran, Sophie; Counsell, Serena J; Edwards, A David; Burdet, Etienne

    2016-01-01

    Preterm birth engenders an increased risk of conditions like cerebral palsy and therefore this time may be crucial for the brain's developing sensori-motor system. However, little is known about how cortical sensori-motor function matures at this time, whether development is influenced by experience, and about its role in spontaneous motor behavior. We aimed to systematically characterize spatial and temporal maturation of sensori-motor functional brain activity across this period using functional MRI and a custom-made robotic stimulation device. We studied 57 infants aged from 30 + 2 to 43 + 2 weeks postmenstrual age. Following both induced and spontaneous right wrist movements, we saw consistent positive blood oxygen level-dependent functional responses in the contralateral (left) primary somatosensory and motor cortices. In addition, we saw a maturational trend toward faster, higher amplitude, and more spatially dispersed functional responses; and increasing integration of the ipsilateral hemisphere and sensori-motor associative areas. We also found that interhemispheric functional connectivity was significantly related to ex-utero exposure, suggesting the influence of experience-dependent mechanisms. At term equivalent age, we saw a decrease in both response amplitude and interhemispheric functional connectivity, and an increase in spatial specificity, culminating in the establishment of a sensori-motor functional response similar to that seen in adults. © The Author 2015. Published by Oxford University Press.

  6. Brain activation related to the change between bimanual motor programs

    NARCIS (Netherlands)

    de Jong, BM; Willemsen, ATM; Paans, AMJ

    By using positron emission tomography, we aimed to identify cerebral foci of neuronal activation associated with the initiation of a specific motor program. To that end, a state of repeatedly alternating in- and antiphase of bimanual flexion and extension movements was compared with similar movement

  7. Combined motor disturbances following severe traumatic brain injury: an integrative long-term treatment approach.

    Science.gov (United States)

    Keren, O; Reznik, J; Groswasser, Z

    2001-07-01

    Patients surviving severe traumatic brain injury (TBI) often suffer from residual impairments in motor control, communication skills, cognition and social behaviour. These distinctly hamper their capability to return to their 'pre-trauma' activity. Comprehensive and integrated rehabilitation programmes initiate, during the acute phase, a prolonged treatment process which starts at the most sophisticated medical systems. There is no clear end point for the treatment of these patients, since the recovery process and the rehabilitation activity may continue for years, even after patients return home to live with their families. The inherent inability to make a firm early prediction regarding outcome of patients and the late appearance of additional symptoms stress the need for a comprehensive close long-term follow-up. The following presentation concerns the description of the treatment strategy and long-term improvement of a 22-year-old male who suffered from very severe TBI. On admission to the emergency room, he was in the decerebrated position and his Glasgow Coma Scale (GCS) was at the lowest (3). The focus of this presentation is on the recovery of motor function. The initial motor disabilities included weakness in all four limbs, in particular left hemiplegia, and right hemiparesis with severe bilateral ataxic elements and a marked tremor of the right arm. Range of motion was limited in hips, and he suffered from stiff trunk and neck. Goals of physiotherapy were directed towards improving range of motion (ROM) and active movement. Casting, use of orthoses, biofeedback, hydrotherapy, hippotherapy, medication and nerve blocks for reducing spasticity were timely applied during the process. The motor improvement in this very severe TBI patient who is now over 3 years post-injury still continues and has a functional meaning. He has succeeded in being able to stand up by himself from a chair and is able to walk unaided and without orthoses for very short distances

  8. speed control of dc motor on load using fuzzy logic controller

    African Journals Online (AJOL)

    HP

    STUDY OF EMERGENCY LUBE OIL PUMP MOTOR OF H25 HITACHI. TURBINE GENERATOR ... with a reference, and if there is an offset, the controller takes action to ... magnetic flux of the air-gap that exists in the motor provided the field is ... Figure 3: Block Diagram of Field-Controlled DC Motor for Driving Lube Oil Pump.

  9. Broad Application of a Reconfigurable Motor Controller, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An ultra-miniature (<50 grams) high-performance brushless-motor controller, code named 'Puck', has been developed by Barrett for Earth-based mobile-manipulation...

  10. Postural control and central motor pathway involvement in type 2 ...

    African Journals Online (AJOL)

    Mona Mokhtar El Bardawil

    2013-04-18

    Apr 18, 2013 ... Postural control and central motor pathway involvement in type 2 .... with a high power 90 mm circular coil, capable of generating. 2 T maximum field ..... advanced glycation end products, oxidative damage and microvascular ...

  11. The roles of the olivocerebellar pathway in motor learning and motor control. A consensus paper

    Science.gov (United States)

    Lang, Eric J.; Apps, Richard; Bengtsson, Fredrik; Cerminara, Nadia L.; De Zeeuw, Chris I.; Ebner, Timothy J.; Heck, Detlef H.; Jaeger, Dieter; Jörntell, Henrik; Kawato, Mitsuo; Otis, Thomas S.; Ozyildirim, Ozgecan; Popa, Laurentiu S.; Reeves, Alexander M.B.; Schweighofer, Nicolas; Sugihara, Izumi; Xiao, Jianqiang

    2016-01-01

    For many decades the predominant view in the cerebellar field has been that the olivocerebellar system's primary function is to induce plasticity in the cerebellar cortex, specifically, at the parallel fiber-Purkinje cell synapse. However, it has also long been proposed that the olivocerebellar system participates directly in motor control by helping to shape ongoing motor commands being issued by the cerebellum. Evidence consistent with both hypotheses exists; however, they are often investigated as mutually exclusive alternatives. In contrast, here we take the perspective that the olivocerebellar system can contribute to both the motor learning and motor control functions of the cerebellum, and might also play a role in development. We then consider the potential problems and benefits of its having multiple functions. Moreover, we discuss how its distinctive characteristics (e.g., low firing rates, synchronization, variable complex spike waveform) make it more or less suitable for one or the other of these functions, and why its having a dual role makes sense from an evolutionary perspective. We did not attempt to reach a consensus on the specific role(s) the olivocerebellar system plays in different types of movements, as that will ultimately be determined experimentally; however, collectively, the various contributions highlight the flexibility of the olivocerebellar system, and thereby suggest it has the potential to act in both the motor learning and motor control functions of the cerebellum. PMID:27193702

  12. A New Torque Control System of Permanent Magnet Synchronous Motor

    Directory of Open Access Journals (Sweden)

    Evstratov Andrey

    2017-01-01

    Full Text Available The article describes a new approach to control of permanent magnet synchronous motor drive based on the analysis of the electromechanical transformation. The proposed control system provides quick response and low ripple of the motor torque and flux. To synthesis this control system, the authors put the electromagnetic torque and the modulus of stator flux vector as controlled values and use the Lyapunov’s second method. In addition, the stator voltage constriction and ability of low-pass filtration are taken into account. The investigation of the proposed control system has carried out with the simulation and the experimental research which have confirmed that the proposed control system correspond to all above-mentioned control tasks and the permanent magnet synchronous motor controlled under this system may be recommended to use in robotics.

  13. Behavioural Models of Motor Control and Short-Term Memory

    OpenAIRE

    Imanaka, Kuniyasu; Funase, Kozo; Yamauchi, Masaki

    1995-01-01

    We examined in this review article the behavioural and conceptual models of motor control and short-term memory which have intensively been investigated since the 1970s. First, we reviewed both the dual-storage model of short-term memory in which movement information is stored and a typical model of motor control which emphasizes the importance of efferent factors. We then examined two models of preselection effects: a cognitive model and a cognitive/ efferent model. Following this we reviewe...

  14. Hardware Evolution of Analog Speed Controllers for a DC Motor

    Science.gov (United States)

    Gwaltney, David A.; Ferguson, Michael I.

    2003-01-01

    This viewgraph presentation provides information on the design of analog speed controllers for DC motors on aerospace systems. The presentation includes an overview of controller evolution, evolvable controller configuration, an emphasis on proportion integral (PI) controllers, schematic diagrams, and experimental results.

  15. Soft-Starting Power-Factor Motor Controller

    Science.gov (United States)

    Nola, F. J.

    1983-01-01

    Three-phase power-factor controller with soft start is based on earlier version that does not control starting transients. Additional components serve to turn off "run" command signal and substitute gradual startup command signal during preset startup interval. Improved controller reduces large current surge that usually accompanies starting. Controller applies power smoothly, without causing motor vibrations.

  16. Neurological Change after Gamma Knife Radiosurgery for Brain Metastases Involving the Motor Cortex

    Science.gov (United States)

    Park, Chang-Yong; Choi, Hyun-Yong; Lee, Sang-Ryul; Roh, Tae Hoon; Seo, Mi-Ra

    2016-01-01

    Background Although Gamma Knife radiosurgery (GKRS) can provide beneficial therapeutic effects for patients with brain metastases, lesions involving the eloquent areas carry a higher risk of neurologic deterioration after treatment, compared to those located in the non-eloquent areas. We aimed to investigate neurological change of the patients with brain metastases involving the motor cortex (MC) and the relevant factors related to neurological deterioration after GKRS. Methods We retrospectively reviewed clinical, radiological and dosimetry data of 51 patients who underwent GKRS for 60 brain metastases involving the MC. Prior to GKRS, motor deficits existed in 26 patients (50.9%). The mean target volume was 3.2 cc (range 0.001–14.1) at the time of GKRS, and the mean prescription dose was 18.6 Gy (range 12–24 Gy). Results The actuarial median survival time from GKRS was 19.2±5.0 months. The calculated local tumor control rates at 6 and 12 months after GKRS were 89.7% and 77.4%, respectively. During the median clinical follow-up duration of 12.3±2.6 months (range 1–54 months), 18 patients (35.3%) experienced new or worsened neurologic deficits with a median onset time of 2.5±0.5 months (range 0.3–9.7 months) after GKRS. Among various factors, prescription dose (>20 Gy) was a significant factor for the new or worsened neurologic deficits in univariate (p=0.027) and multivariate (p=0.034) analysis. The managements of 18 patients were steroid medication (n=10), boost radiation therapy (n=5), and surgery (n=3), and neurological improvement was achieved in 9 (50.0%). Conclusion In our series, prescription dose (>20 Gy) was significantly related to neurological deterioration after GKRS for brain metastases involving the MC. Therefore, we suggest that careful dose adjustment would be required for lesions involving the MC to avoid neurological deterioration requiring additional treatment in the patients with limited life expectancy. PMID:27867921

  17. Space motion sickness: The sensory motor controls and cardiovascular correlation

    Science.gov (United States)

    Souvestre, Philippe A.; Blaber, Andrew P.; Landrock, Clinton K.

    Background and PurposeSpace motion sickness (SMS) and related symptoms remain a major limiting factor in Space operations. A recent comprehensive literature review [J.R. Lackner, Z. DiZio, Space motion sickness, Experimental Brain Research 175 (2006) 377-399, doi 10.1007/s00221-006-0697-y] concluded that SMS does not represent a unique diagnostic entity, and there is no adequate predictor of SMS' susceptibility and severity. No countermeasure has been found reliable to prevent or treat SMS symptoms onset. Recent neurophysiological findings on sensory-motor controls monitoring [P.A. Souvestre, C. Landrock, Biomedical-performance monitoring and assessment of astronauts by means of an ocular vestibular monitoring system, Acta Astronautica, 60 (4-7) (2007) 313-321, doi:10.1016/j.actaastro.2006.08.013] and heart-rate variability (HRV) measurements relationship could explain post-flight orthostatic intolerance (PFOI) in astronauts [A.P. Blaber, R.L. Bondar, M.S. Kassam, Heart rate variability and short duration space flight: relationship to post-flight orthostatic intolerance, BMC Physiology 4 (2004) 6]. These two methodologies are generally overlooked in SMS' analysis. In this paper we present the case for a strong relationship between sensory-motor controls related symptoms, including orthostatic intolerance (OI) and SMS symptoms. MethodsThis paper expands on several previously published papers [J.R. Lackner, Z. DiZio, Space motion sickness, Experimental Brain Research 175 (2006) 377-399, doi 10.1007/s00221-006-0697-y; P.A. Souvestre, C. Landrock, Biomedical-performance monitoring and assessment of astronauts by means of an ocular vestibular monitoring system, Acta Astronautica, 60 (4-7) (2007) 313-321, doi:10.1016/j.actaastro.2006.08.013] along with an updated literature review. An analysis of a 10-year period clinical data from trauma patients experiencing postural deficiency syndrome (PDS) show assessment and monitoring techniques which successfully identify trauma

  18. Implicit sequence-specific motor learning after sub-cortical stroke is associated with increased prefrontal brain activations: An fMRI study

    Science.gov (United States)

    Meehan, Sean K.; Randhawa, Bubblepreet; Wessel, Brenda; Boyd, Lara A.

    2010-01-01

    Implicit motor learning is preserved after stroke, but how the brain compensates for damage to facilitate learning is unclear. We used a random effects analysis to determine how stroke alters patterns of brain activity during implicit sequence-specific motor learning as compared to general improvements in motor control. Nine healthy participants and 9 individuals with chronic, right focal sub-cortical stroke performed a continuous joystick-based tracking task during an initial fMRI session, over 5 days of practice, and a retention test during a separate fMRI session. Sequence-specific implicit motor learning was differentiated from general improvements in motor control by comparing tracking performance on a novel, repeated tracking sequences during early practice and again at the retention test. Both groups demonstrated implicit sequence-specific motor learning at the retention test, yet substantial differences were apparent. At retention, healthy control participants demonstrated increased BOLD response in left dorsal premotor cortex (BA 6) but decreased BOLD response left dorsolateral prefrontal cortex (DLPFC; BA 9) during repeated sequence tracking. In contrast, at retention individuals with stroke did not show this reduction in DLPFC during repeated tracking. Instead implicit sequence-specific motor learning and general improvements in motor control were associated with increased BOLD response in the left middle frontal gyrus BA 8, regardless of sequence type after stroke. These data emphasize the potential importance of a prefrontal-based attentional network for implicit motor learning after stroke. The present study is the first to highlight the importance of the prefrontal cortex for implicit sequence-specific motor learning after stroke. PMID:20725908

  19. From cognitive motor preparation to visual processing: The benefits of childhood fitness to brain health.

    Science.gov (United States)

    Berchicci, M; Pontifex, M B; Drollette, E S; Pesce, C; Hillman, C H; Di Russo, F

    2015-07-09

    The association between a fit body and a fit brain in children has led to a rise of behavioral and neuroscientific research. Yet, the relation of cardiorespiratory fitness on premotor neurocognitive preparation with early visual processing has received little attention. Here, 41 healthy, lower and higher fit preadolescent children were administered a modified version of the Eriksen flanker task while electroencephalography (EEG) and behavioral measures were recorded. Event-related potentials (ERPs) locked to the stimulus onset with an earlier than usual baseline (-900/-800 ms) allowed investigation of both the usual post-stimulus (i.e., the P1, N1 and P2) as well as the pre-stimulus ERP components, such as the Bereitschaftspotential (BP) and the prefrontal negativity (pN component). At the behavioral level, aerobic fitness was associated response accuracy, with higher fit children being more accurate than lower fit children. Fitness-related differences selectively emerged at prefrontal brain regions during response preparation, with larger pN amplitude for higher than lower fit children, and at early perceptual stages after stimulus onset, with larger P1 and N1 amplitudes in higher relative to lower fit children. Collectively, the results suggest that the benefits of being aerobically fit appear at the stage of cognitive preparation prior to stimulus presentation and the behavioral response during the performance of a task that challenges cognitive control. Further, it is likely that enhanced activity in prefrontal brain areas may improve cognitive control of visuo-motor tasks, allowing for stronger proactive inhibition and larger early allocation of selective attention resources on relevant external stimuli. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  20. Simple Motor Control Concept Results High Efficiency at High Velocities

    Science.gov (United States)

    Starin, Scott; Engel, Chris

    2013-09-01

    The need for high velocity motors in space applications for reaction wheels and detectors has stressed the limits of Brushless Permanent Magnet Motors (BPMM). Due to inherent hysteresis core losses, conventional BPMMs try to balance the need for torque verses hysteresis losses. Cong-less motors have significantly less hysteresis losses but suffer from lower efficiencies. Additionally, the inherent low inductance in cog-less motors result in high ripple currents or high switching frequencies, which lowers overall efficiency and increases performance demands on the control electronics.However, using a somewhat forgotten but fully qualified technology of Isotropic Magnet Motors (IMM), extremely high velocities may be achieved at low power input using conventional drive electronics. This paper will discuss the trade study efforts and empirical test data on a 34,000 RPM IMM.

  1. Orderly recruitment of motor units under optical control in vivo.

    Science.gov (United States)

    Llewellyn, Michael E; Thompson, Kimberly R; Deisseroth, Karl; Delp, Scott L

    2010-10-01

    A drawback of electrical stimulation for muscle control is that large, fatigable motor units are preferentially recruited before smaller motor units by the lowest-intensity electrical cuff stimulation. This phenomenon limits therapeutic applications because it is precisely the opposite of the normal physiological (orderly) recruitment pattern; therefore, a mechanism to achieve orderly recruitment has been a long-sought goal in physiology, medicine and engineering. Here we demonstrate a technology for reliable orderly recruitment in vivo. We find that under optical control with microbial opsins, recruitment of motor units proceeds in the physiological recruitment sequence, as indicated by multiple independent measures of motor unit recruitment including conduction latency, contraction and relaxation times, stimulation threshold and fatigue. As a result, we observed enhanced performance and reduced fatigue in vivo. These findings point to an unanticipated new modality of neural control with broad implications for nervous system and neuromuscular physiology, disease research and therapeutic innovation.

  2. Efficient speed control of induction motor using RBF based model reference adaptive control method

    OpenAIRE

    Kilic, Erdal; Ozcalik, Hasan Riza; Yilmaz, Saban

    2017-01-01

    This paper proposes a model reference adaptive speed controller based on artificial neural network for induction motor drives. The performance of traditional feedback controllers has been insufficient in speed control of induction motors due to nonlinear structure of the system, changing environmental conditions, and disturbance input effects. A successful speed control of induction motor requires a nonlinear control system. On the other hand, in recent years, it has been demonstrated that ar...

  3. The effect of deep brain stimulation on the speech motor system.

    Science.gov (United States)

    Mücke, Doris; Becker, Johannes; Barbe, Michael T; Meister, Ingo; Liebhart, Lena; Roettger, Timo B; Dembek, Till; Timmermann, Lars; Grice, Martine

    2014-08-01

    Chronic deep brain stimulation of the nucleus ventralis intermedius is an effective treatment for individuals with medication-resistant essential tremor. However, these individuals report that stimulation has a deleterious effect on their speech. The present study investigates one important factor leading to these effects: the coordination of oral and glottal articulation. Sixteen native-speaking German adults with essential tremor, between 26 and 86 years old, with and without chronic deep brain stimulation of the nucleus ventralis intermedius and 12 healthy, age-matched subjects were recorded performing a fast syllable repetition task (/papapa/, /tatata/, /kakaka/). Syllable duration and voicing-to-syllable ratio as well as parameters related directly to consonant production, voicing during constriction, and frication during constriction were measured. Voicing during constriction was greater in subjects with essential tremor than in controls, indicating a perseveration of voicing into the voiceless consonant. Stimulation led to fewer voiceless intervals (voicing-to-syllable ratio), indicating a reduced degree of glottal abduction during the entire syllable cycle. Stimulation also induced incomplete oral closures (frication during constriction), indicating imprecise oral articulation. The detrimental effect of stimulation on the speech motor system can be quantified using acoustic measures at the subsyllabic level.

  4. Design and simulation of permanent magnet synchronous motor control system

    Science.gov (United States)

    Li, Li; Liu, Yongqiu

    2018-06-01

    In recent years, with the development of power electronics, microelectronics, new motor control theory and rare earth permanent magnet materials, permanent magnet synchronous motors have been rapidly applied. Permanent magnet synchronous motors have the advantages of small size, low loss and high efficiency. Today, energy conservation and environmental protection are increasingly valued. It is very necessary to study them. Permanent magnet synchronous motor control system has a wide range of application prospects in the fields of electric vehicles, ships and other transportation. Using the simulation function of MATLAB/SIMULINK, a modular design structure was used to simulate the whole system model of speed loop adjustment, current PI modulation, SVPWM (Space Vector Pulse Width Module) wave generation and double closed loop. The results show that this control method has good robustness, and this method can improve the design efficiency and shorten the system design time. In this article, the analysis of the control principle of modern permanent magnet synchronous motor and the various processes of MATLAB simulation application will be analyzed in detail. The basic theory, basic method and application technology of the permanent magnet synchronous motor control system are systematically introduced.

  5. User's Self-Prediction of Performance in Motor Imagery Brain-Computer Interface.

    Science.gov (United States)

    Ahn, Minkyu; Cho, Hohyun; Ahn, Sangtae; Jun, Sung C

    2018-01-01

    Performance variation is a critical issue in motor imagery brain-computer interface (MI-BCI), and various neurophysiological, psychological, and anatomical correlates have been reported in the literature. Although the main aim of such studies is to predict MI-BCI performance for the prescreening of poor performers, studies which focus on the user's sense of the motor imagery process and directly estimate MI-BCI performance through the user's self-prediction are lacking. In this study, we first test each user's self-prediction idea regarding motor imagery experimental datasets. Fifty-two subjects participated in a classical, two-class motor imagery experiment and were asked to evaluate their easiness with motor imagery and to predict their own MI-BCI performance. During the motor imagery experiment, an electroencephalogram (EEG) was recorded; however, no feedback on motor imagery was given to subjects. From EEG recordings, the offline classification accuracy was estimated and compared with several questionnaire scores of subjects, as well as with each subject's self-prediction of MI-BCI performance. The subjects' performance predictions during motor imagery task showed a high positive correlation ( r = 0.64, p performance even without feedback information. This implies that the human brain is an active learning system and, by self-experiencing the endogenous motor imagery process, it can sense and adopt the quality of the process. Thus, it is believed that users may be able to predict MI-BCI performance and results may contribute to a better understanding of low performance and advancing BCI.

  6. Age differences in the motor control of speech: An fMRI study of healthy aging.

    Science.gov (United States)

    Tremblay, Pascale; Sato, Marc; Deschamps, Isabelle

    2017-05-01

    Healthy aging is associated with a decline in cognitive, executive, and motor processes that are concomitant with changes in brain activation patterns, particularly at high complexity levels. While speech production relies on all these processes, and is known to decline with age, the mechanisms that underlie these changes remain poorly understood, despite the importance of communication on everyday life. In this cross-sectional group study, we investigated age differences in the neuromotor control of speech production by combining behavioral and functional magnetic resonance imaging (fMRI) data. Twenty-seven healthy adults underwent fMRI while performing a speech production task consisting in the articulation of nonwords of different sequential and motor complexity. Results demonstrate strong age differences in movement time (MT), with longer and more variable MT in older adults. The fMRI results revealed extensive age differences in the relationship between BOLD signal and MT, within and outside the sensorimotor system. Moreover, age differences were also found in relation to sequential complexity within the motor and attentional systems, reflecting both compensatory and de-differentiation mechanisms. At very high complexity level (high motor complexity and high sequence complexity), age differences were found in both MT data and BOLD response, which increased in several sensorimotor and executive control areas. Together, these results suggest that aging of motor and executive control mechanisms may contribute to age differences in speech production. These findings highlight the importance of studying functionally relevant behavior such as speech to understand the mechanisms of human brain aging. Hum Brain Mapp 38:2751-2771, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  7. An Adaptive Speed Control Approach for DC Shunt Motors

    Directory of Open Access Journals (Sweden)

    Ruben Tapia-Olvera

    2016-11-01

    Full Text Available A B-spline neural networks-based adaptive control technique for angular speed reference trajectory tracking tasks with highly efficient performance for direct current shunt motors is proposed. A methodology for adaptive control and its proper training procedure are introduced. This algorithm sets the control signal without using a detailed mathematical model nor exact values of the parameters of the nonlinear dynamic system. The proposed robust adaptive tracking control scheme only requires measurements of the velocity output signal. Thus, real-time measurements or estimations of acceleration, current and disturbance signals are avoided. Experimental results confirm the efficient and robust performance of the proposed control approach for highly demanding motor operation conditions exposed to variable-speed reference trajectories and completely unknown load torque. Hence, laboratory experimental tests on a direct current shunt motor prove the viability of the proposed adaptive output feedback trajectory tracking control approach.

  8. Draft evidence report : traumatic brain injury and commercial motor vehicle driver safety (comprehensive review).

    Science.gov (United States)

    2009-03-30

    Purpose of this evidence report is to address several key questions posed by the Federal Motor Carrier Safety Administration : Key question 1: What is the impact of traumatic brain injury on crash risk/driving performance? Key question 2: What factor...

  9. Study on Control of Brain Temperature for Brain Hypothermia Treatment

    Science.gov (United States)

    Gaohua, Lu; Wakamatsu, Hidetoshi

    The brain hypothermia treatment is an attractive therapy for the neurologist because of its neuroprotection in hypoxic-ischemic encephalopathy patients. The present paper deals with the possibility of controlling the brain and other viscera in different temperatures from the viewpoint of system control. It is theoretically attempted to realize the special brain hypothermia treatment to cool only the head but to warm the body by using the simple apparatus such as the cooling cap, muffler and warming blanket. For this purpose, a biothermal system concerning the temperature difference between the brain and the other thoracico-abdominal viscus is synthesized from the biothermal model of hypothermic patient. The output controllability and the asymptotic stability of the system are examined on the basis of its structure. Then, the maximum temperature difference to be realized is shown dependent on the temperature range of the apparatus and also on the maximum gain determined from the coefficient matrices A, B and C of the biothermal system. Its theoretical analysis shows the realization of difference of about 2.5°C, if there is absolutely no constraint of the temperatures of the cooling cap, muffler and blanket. It is, however, physically unavailable. Those are shown by simulation example of the optimal brain temperature regulation using a standard adult database. It is thus concluded that the surface cooling and warming apparatus do no make it possible to realize the special brain hypothermia treatment, because the brain temperature cannot be cooled lower than those of other viscera in an appropriate temperature environment. This study shows that the ever-proposed good method of clinical treatment is in principle impossible in the actual brain hypothermia treatment.

  10. Precision electronic speed controller for an alternating-current motor

    Science.gov (United States)

    Bolie, V.W.

    A high precision controller for an alternating-current multi-phase electrical motor that is subject to a large inertial load. The controller was developed for controlling, in a neutron chopper system, a heavy spinning rotor that must be rotated in phase-locked synchronism with a reference pulse train that is representative of an ac power supply signal having a meandering line frequency. The controller includes a shaft revolution sensor which provides a feedback pulse train representative of the actual speed of the motor. An internal digital timing signal generator provides a reference signal which is compared with the feedback signal in a computing unit to provide a motor control signal. The motor control signal is a weighted linear sum of a speed error voltage, a phase error voltage, and a drift error voltage, each of which is computed anew with each revolution of the motor shaft. The speed error signal is generated by a novel vernier-logic circuit which is drift-free and highly sensitive to small speed changes. The phase error is also computed by digital logic, with adjustable sensitivity around a 0 mid-scale value. The drift error signal, generated by long-term counting of the phase error, is used to compensate for any slow changes in the average friction drag on the motor. An auxillary drift-byte status sensor prevents any disruptive overflow or underflow of the drift-error counter. An adjustable clocked-delay unit is inserted between the controller and the source of the reference pulse train to permit phase alignment of the rotor to any desired offset angle. The stator windings of the motor are driven by two amplifiers which are provided with input signals having the proper quadrature relationship by an exciter unit consisting of a voltage controlled oscillator, a binary counter, a pair of read-only memories, and a pair of digital-to-analog converters.

  11. A flight simulator control system using electric torque motors

    Science.gov (United States)

    Musick, R. O.; Wagner, C. A.

    1975-01-01

    Control systems are required in flight simulators to provide representative stick and rudder pedal characteristics. A system has been developed that uses electric dc torque motors instead of the more common hydraulic actuators. The torque motor system overcomes certain disadvantages of hydraulic systems, such as high cost, high power consumption, noise, oil leaks, and safety problems. A description of the torque motor system is presented, including both electrical and mechanical design as well as performance characteristics. The system develops forces sufficiently high for most simulations, and is physically small and light enough to be used in most motion-base cockpits.

  12. Control de un motor paso a paso: PIC, USB, C#

    OpenAIRE

    Fernández Aragón, Iñigo

    2011-01-01

    El objetivo de este proyecto fin de carrera es crear un equipo con el que comprender y controlar, desde el ordenador, el funcionamiento de un motor paso a paso bifásico de imanes permanentes, a través de una comunicación USB, la ayuda de un microprocesador y el imprescindible driver del motor paso a paso. Uno de los elementos utilizados en el control de un motor paso a paso es el microprocesador, encargado tanto de enviar las consignas al controlador (driver), como de captar...

  13. Similar brain networks for detecting visuo-motor and visuo-propriceptive synchrony

    DEFF Research Database (Denmark)

    Balslev, Daniela; Nielsen, Finn Årup; Lund, Torben Ellegaard

    2006-01-01

    is compared with either (a) the proprioceptive feedback or with (b) the motor command and if they match, then the external stimulus is identified as feedback. Hypothesis (a) predicts that the neural mechanisms or brain areas involved in distinguishing self from other during passive and active movement....... However, no statistically significant difference was found between these sets of activated areas when the active and passive movement conditions were compared. With a posterior probability of 0.95, no brain voxel had a contrast effect above 0.11% of the whole-brain mean signal. These results do...

  14. Whole-brain structural connectivity in dyskinetic cerebral palsy and its association with motor and cognitive function.

    Science.gov (United States)

    Ballester-Plané, Júlia; Schmidt, Ruben; Laporta-Hoyos, Olga; Junqué, Carme; Vázquez, Élida; Delgado, Ignacio; Zubiaurre-Elorza, Leire; Macaya, Alfons; Póo, Pilar; Toro, Esther; de Reus, Marcel A; van den Heuvel, Martijn P; Pueyo, Roser

    2017-09-01

    Dyskinetic cerebral palsy (CP) has long been associated with basal ganglia and thalamus lesions. Recent evidence further points at white matter (WM) damage. This study aims to identify altered WM pathways in dyskinetic CP from a standardized, connectome-based approach, and to assess structure-function relationship in WM pathways for clinical outcomes. Individual connectome maps of 25 subjects with dyskinetic CP and 24 healthy controls were obtained combining a structural parcellation scheme with whole-brain deterministic tractography. Graph theoretical metrics and the network-based statistic were applied to compare groups and to correlate WM state with motor and cognitive performance. Results showed a widespread reduction of WM volume in CP subjects compared to controls and a more localized decrease in degree (number of links per node) and fractional anisotropy (FA), comprising parieto-occipital regions and the hippocampus. However, supramarginal gyrus showed a significantly higher degree. At the network level, CP subjects showed a bilateral pathway with reduced FA, comprising sensorimotor, intraparietal and fronto-parietal connections. Gross and fine motor functions correlated with FA in a pathway comprising the sensorimotor system, but gross motor also correlated with prefrontal, temporal and occipital connections. Intelligence correlated with FA in a network with fronto-striatal and parieto-frontal connections, and visuoperception was related to right occipital connections. These findings demonstrate a disruption in structural brain connectivity in dyskinetic CP, revealing general involvement of posterior brain regions with relative preservation of prefrontal areas. We identified pathways in which WM integrity is related to clinical features, including but not limited to the sensorimotor system. Hum Brain Mapp 38:4594-4612, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  15. Fault tolerant vector control of induction motor drive

    International Nuclear Information System (INIS)

    Odnokopylov, G; Bragin, A

    2014-01-01

    For electric composed of technical objects hazardous industries, such as nuclear, military, chemical, etc. an urgent task is to increase their resiliency and survivability. The construction principle of vector control system fault-tolerant asynchronous electric. Displaying recovery efficiency three-phase induction motor drive in emergency mode using two-phase vector control system. The process of formation of a simulation model of the asynchronous electric unbalance in emergency mode. When modeling used coordinate transformation, providing emergency operation electric unbalance work. The results of modeling transient phase loss motor stator. During a power failure phase induction motor cannot save circular rotating field in the air gap of the motor and ensure the restoration of its efficiency at rated torque and speed

  16. Programmable logic controller based synchronous motor excitation system

    Directory of Open Access Journals (Sweden)

    Janda Žarko

    2011-01-01

    Full Text Available This paper presents a 3.5 MW synchronous motor excitation system reconstruction. In the proposed solution programmable logic controller is used to control motor, which drives the turbo compressor. Comparing to some other solutions that are used in similar situations, the proposed solution is superior due to its flexibility and usage of mass-production hardware. Moreover, the implementation of PLC enables easy integration of the excitation system with the other technological processes in the plant as well as in the voltage regulation of 'smart grid' system. Also, implementation of various optimization algorithms can be done comfortably and it does not require additional investment in hardware. Some experimental results that depict excitation current during motor start-up, as well as, measured static characteristics of the motor, were presented.

  17. Echoes on the motor network: how internal motor control structures afford sensory experience.

    Science.gov (United States)

    Burgess, Jed D; Lum, Jarrad A G; Hohwy, Jakob; Enticott, Peter G

    2017-12-01

    Often, during daily experiences, hearing peers' actions can activate motor regions of the CNS. This activation is termed auditory-motor resonance (AMR) and is thought to represent an internal simulation of one's motor memories. Currently, AMR is demonstrated at the neuronal level in the Macaque and songbird, in conjunction with evidence on a systems level in humans. Here, we review evidence of AMR development from a motor control perspective. In the context of internal modelling, we consider data that demonstrates sensory-guided motor learning and action maintenance, particularly the notion of sensory comparison seen during songbird vocalisation. We suggest that these comparisons generate accurate sensory-to-motor inverse mappings. Furthermore, given reports of mapping decay after songbird learning, we highlight the proposal that the maintenance of these sensorimotor maps potentially explains why frontoparietal regions are activated upon hearing known sounds (i.e., AMR). In addition, we also recommend that activation of these types of internal models outside of action execution may provide an ecological advantage when encountering known stimuli in ambiguous conditions.

  18. Dual motor drive vehicle speed synchronization and coordination control strategy

    Science.gov (United States)

    Huang, Hao; Tu, Qunzhang; Jiang, Chenming; Ma, Limin; Li, Pei; Zhang, Hongxing

    2018-04-01

    Multi-motor driven systems are more and more widely used in the field of electric engineering vehicles, as a result of the road conditions and the variable load of engineering vehicles, makes multi-motors synchronization coordinated control system as a key point of the development of the electric vehicle drive system. This paper based on electrical machinery transmission speed in the process of engineering vehicles headed for coordinated control problem, summarized control strategies at home and abroad in recent years, made analysis and comparison of the characteristics, finally discussed the trend of development of the multi-motor coordination control, provided a reference for synchronized control system research of electric drive engineering vehicles.

  19. Adaptive neuro-fuzzy controller of switched reluctance motor

    Directory of Open Access Journals (Sweden)

    Tahour Ahmed

    2007-01-01

    Full Text Available This paper presents an application of adaptive neuro-fuzzy (ANFIS control for switched reluctance motor (SRM speed. The ANFIS has the advantages of expert knowledge of the fuzzy inference system and the learning capability of neural networks. An adaptive neuro-fuzzy controller of the motor speed is then designed and simulated. Digital simulation results show that the designed ANFIS speed controller realizes a good dynamic behaviour of the motor, a perfect speed tracking with no overshoot and a good rejection of impact loads disturbance. The results of applying the adaptive neuro-fuzzy controller to a SRM give better performance and high robustness than those obtained by the application of a conventional controller (PI.

  20. Nonlinear Control of Induction Motors: A Performance Study

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Vadstrup, P.; Børsting, H.

    1998-01-01

    A novel approach to control of induction motors based on nonlinear state feedback has previously been presented by the authors. The resulting scheme gives a linearized input-output decoupling of the torque and the amplitude of the field. The proposed approach is used to design controllers for the...... for the field amplitude and the motor torque. The method is compared with the traditional Rotor Field Oriented Control method as regards variations in rotor resistance an magnetizing inductance......A novel approach to control of induction motors based on nonlinear state feedback has previously been presented by the authors. The resulting scheme gives a linearized input-output decoupling of the torque and the amplitude of the field. The proposed approach is used to design controllers...

  1. Personal Computer Based Controller For Switched Reluctance Motor Drives

    Science.gov (United States)

    Mang, X.; Krishnan, R.; Adkar, S.; Chandramouli, G.

    1987-10-01

    Th9, switched reluctance motor (SRM) has recently gained considerable attention in the variable speed drive market. Two important factors that have contributed to this are, the simplicity of construction and the possibility of developing low cost con-trollers with minimum number of switching devices in the drive circuits. This is mainly due to the state-of-art of the present digital circuits technology and the low cost of switching devices. The control of this motor drive is under research. Optimized performance of the SRM motor drive is very dependent on the integration of the controller, converter and the motor. This research on system integration involves considerable changes in the control algorithms and their implementation. A Personal computer (PC) based controller is very appropriate for this purpose. Accordingly, the present paper is concerned with the design of a PC based controller for a SRM. The PC allows for real-time microprocessor control with the possibility of on-line system parameter modifications. Software reconfiguration of this controller is easier than a hardware based controller. User friendliness is a natural consequence of such a system. Considering the low cost of PCs, this controller will offer an excellent cost-effective means of studying the control strategies for the SRM drive intop greater detail than in the past.

  2. The effect of gravity on the motor control of landing

    OpenAIRE

    Gambelli, Clément

    2016-01-01

    Landing from a fall is a complex action requiring the prediction of the instant of contact with the ground. Since humans have developed motor actions on Earth, the nervous system and the sensory input processing are optimized to the Earth’s gravity. The aim of this study is to assess human motor control of landing in different conditions of fall initiation, simulated gravity and sensory neural input. Hypergravity was simulated either on Earth with a Subject Loading System (SLS) generating a p...

  3. High power density superconducting motor for control applications

    International Nuclear Information System (INIS)

    Lopez, J; Granados, X; Lloberas, J; Torres, R; Grau, J; Maynou, R; Bosch, R

    2008-01-01

    A high dynamics superconducting low power motor for control applications has been considered for design. The rotor is cylindrical with machined bulks that generate the field by trapping flux in a four poles configuration. The toothless iron armature is wound by copper, acting iron only as magnetic screen. Details of the magnetic assembling, cryogenics and electrical supply conditioning will be reported. Improvements due to the use of a superconducting set are compared with performances of equivalent conventional motors

  4. Brain Computer Interface: Assessment of Spinal Cord Injury Patient towards Motor Movement through EEG application

    Directory of Open Access Journals (Sweden)

    Syam Syahrull Hi-Fi

    2017-01-01

    Full Text Available Electroencephalography (EEG associated with motor task have been comprehensively investigated and it can also describe the brain activities while spinal cord injury (SCI patient with para/tetraplegia performing movement with their limbs. This paper reviews on conducted research regarding application of brain computer interface (BCI that offer alternative for neural impairments community such as spinal cord injury patient (SCI which include the experimental design, signal analysis of EEG band signal and data processing methods. The findings claim that the EEG signals of SCI patients associated with movement tasks can be stimulated through mental and motor task. Other than that EEG signal component such as alpha and beta frequency bands indicate significance for analysing the brain activity of subjects with SCI during movements.

  5. Remote Traumatic Brain Injury Is Associated with Motor Dysfunction in Older Military Veterans.

    Science.gov (United States)

    Gardner, Raquel C; Peltz, Carrie B; Kenney, Kimbra; Covinsky, Kenneth E; Diaz-Arrastia, Ramon; Yaffe, Kristine

    2017-09-01

    Traumatic brain injury (TBI) has been identified as a risk factor for Parkinson's disease (PD). Motor dysfunction among TBI-exposed elders without PD has not been well characterized. We sought to determine whether remote TBI is a risk factor for motor dysfunction on exam and functionally relevant motor dysfunction in day-to-day life among independently living elders without PD. This is a cross-sectional cohort study of independently living retired military veterans aged 50 or older with (n = 78) and without (n = 85) prior TBI-all without diagnosed PD. To characterize multidimensional aspects of motor function on exam, the Unified Parkinson's Disease Rating Scale (UPDRS) Motor Examination was performed by a board-certified neurologist and used to calculate a modified UPDRS (mUPDRS) global motor score and four domain scores (tremor, rigidity, bradykinesia, and posture/gait). Functionally relevant motor dysfunction was assessed via self-report of falls within the past year. In analyses adjusted for demographics and comorbidities that differed between groups, compared with veterans without TBI, those with moderate-to-severe TBI were more likely to have fallen in past year (33% vs. 14%, risk ratio 2.5 [95% confidence interval 1.1-5.4]), had higher (worse) mUPDRS global motor (p = .03) and posture/gait scores (p = .02), but not higher tremor (p = .70), rigidity (p = .21), or bradykinesia scores (p = .22). Mild TBI was not associated with worse motor function. Remote moderate-to-severe TBI is a risk factor for motor dysfunction-defined as recent falls and impaired posture/gait-among older veterans. TBI-exposed older adults may be ideal candidates for aggressive fall-screening and prevention strategies. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Calibrating EEG-based motor imagery brain-computer interface from passive movement.

    Science.gov (United States)

    Ang, Kai Keng; Guan, Cuntai; Wang, Chuanchu; Phua, Kok Soon; Tan, Adrian Hock Guan; Chin, Zheng Yang

    2011-01-01

    EEG data from performing motor imagery are usually collected to calibrate a subject-specific model for classifying the EEG data during the evaluation phase of motor imagery Brain-Computer Interface (BCI). However, there is no direct objective measure to determine if a subject is performing motor imagery correctly for proper calibration. Studies have shown that passive movement, which is directly observable, induces Event-Related Synchronization patterns that are similar to those induced from motor imagery. Hence, this paper investigates the feasibility of calibrating EEG-based motor imagery BCI from passive movement. EEG data of 12 healthy subjects were collected during motor imagery and passive movement of the hand by a haptic knob robot. The calibration models using the Filter Bank Common Spatial Pattern algorithm on the EEG data from motor imagery were compared against using the EEG data from passive movement. The performances were compared based on the 10×10-fold cross-validation accuracies of the calibration data, and off-line session-to-session transfer kappa values to other sessions of motor imagery performed on another day. The results showed that the calibration performed using passive movement yielded higher model accuracy and off-line session-to-session transfer (73.6% and 0.354) than the calibration performed using motor imagery (71.3% and 0.311), and no significant differences were observed between the two groups (p=0.20, 0.23). Hence, this study shows that it is feasible to calibrate EEG-based motor imagery BCI from passive movement.

  7. Advanced dc motor controller for battery-powered electric vehicles

    Science.gov (United States)

    Belsterling, C. A.

    1981-01-01

    A motor generation set is connected to run from the dc source and generate a voltage in the traction motor armature circuit that normally opposes the source voltage. The functional feasibility of the concept is demonstrated with tests on a Proof of Principle System. An analog computer simulation is developed, validated with the results of the tests, applied to predict the performance of a full scale Functional Model dc Controller. The results indicate high efficiencies over wide operating ranges and exceptional recovery of regenerated energy. The new machine integrates both motor and generator on a single two bearing shaft. The control strategy produces a controlled bidirectional plus or minus 48 volts dc output from the generator permitting full control of a 96 volt dc traction motor from a 48 volt battery, was designed to control a 20 hp traction motor. The controller weighs 63.5 kg (140 lb.) and has a peak efficiency of 90% in random driving modes and 96% during the SAE J 227a/D driving cycle.

  8. Effects of a Single Dose of Erythropoietin on Motor Function and Cognition after Focal Brain Ischemia in Adult Rats

    Directory of Open Access Journals (Sweden)

    Michaela Hralová

    2014-01-01

    Full Text Available We tested the influence of erythropoietin (EPO, a basic cytokine in erythropoiesis regulation, on the process of motor function and cognition after focal brain ischemia induced by a local application of endothelin. Endothelin-1 (ET-1 induced short lasting strong vasoconstriction, with described impact on the structure and on the function of neuronal cells. Neurological description of motor function and Morris water maze test (the swimming test is one of most widely used methods for studying cognitive functions in rodents were used to study the process of learning and memory in three-month-old male albino Wistar rats (n=52. Both tests were performed one week before, and three weeks after ischemia induction (endothelin application on the cortex in the area of a. cerebri media dx.. Experimental group received i.p. injection of EPO (5,000 IU/kg body weight, 10 min before endothelin application. Control group of animals received one i.p. injection of saline at the dose of 1 ml/kg body weight at the same time. Only sham surgery was performed in the third group of animals. Rats with EPO pretreatment before the experimental lesion exhibited significantly better motor and cognitive function then those with saline injection. No significant changes in the motor and cognitive function were found in the third group of rats (sham operated controls.

  9. Using Brain Oscillations and Corticospinal Excitability to Understand and Predict Post-Stroke Motor Function

    Directory of Open Access Journals (Sweden)

    Aurore Thibaut

    2017-05-01

    Full Text Available What determines motor recovery in stroke is still unknown and finding markers that could predict and improve stroke recovery is a challenge. In this study, we aimed at understanding the neural mechanisms of motor function recovery after stroke using neurophysiological markers by means of cortical excitability (transcranial magnetic stimulation—TMS and brain oscillations (electroencephalography—EEG. In this cross-sectional study, 55 subjects with chronic stroke (62 ± 14 yo, 17 women, 32 ± 42 months post-stroke were recruited in two sites. We analyzed TMS measures (i.e., motor threshold—MT—of the affected and unaffected sides and EEG variables (i.e., power spectrum in different frequency bands and different brain regions of the affected and unaffected hemispheres and their correlation with motor impairment as measured by Fugl-Meyer. Multiple univariate and multivariate linear regression analyses were performed to identify the predictors of good motor function. A significant interaction effect of MT in the affected hemisphere and power in beta bandwidth over the central region for both affected and unaffected hemispheres was found. We identified that motor function positively correlates with beta rhythm over the central region of the unaffected hemisphere, while it negatively correlates with beta rhythm in the affected hemisphere. Our results suggest that cortical activity in the affected and unaffected hemisphere measured by EEG provides new insights on the association between high-frequency rhythms and motor impairment, highlighting the role of an excess of beta in the affected central cortical region in poor motor function in stroke recovery.

  10. Motor Control and Neural Plasticity through Interhemispheric Interactions

    Directory of Open Access Journals (Sweden)

    Naoyuki Takeuchi

    2012-01-01

    Full Text Available The corpus callosum, which is the largest white matter structure in the human brain, connects the 2 cerebral hemispheres. It plays a crucial role in maintaining the independent processing of the hemispheres and in integrating information between both hemispheres. The functional integrity of interhemispheric interactions can be tested electrophysiologically in humans by using transcranial magnetic stimulation, electroencephalography, and functional magnetic resonance imaging. As a brain structural imaging, diffusion tensor imaging has revealed the microstructural connectivity underlying interhemispheric interactions. Sex, age, and motor training in addition to the size of the corpus callosum influence interhemispheric interactions. Several neurological disorders change hemispheric asymmetry directly by impairing the corpus callosum. Moreover, stroke lesions and unilateral peripheral impairments such as amputation alter interhemispheric interactions indirectly. Noninvasive brain stimulation changes the interhemispheric interactions between both motor cortices. Recently, these brain stimulation techniques were applied in the clinical rehabilitation of patients with stroke by ameliorating the deteriorated modulation of interhemispheric interactions. Here, we review the interhemispheric interactions and mechanisms underlying the pathogenesis of these interactions and propose rehabilitative approaches for appropriate cortical reorganization.

  11. ON THE ISSUE OF VECTOR CONTROL OF THE ASYNCHRONOUS MOTORS

    Directory of Open Access Journals (Sweden)

    B. I. Firago

    2015-01-01

    Full Text Available The paper considers the issue of one of the widespread types of vector control realization for the asynchronous motors with a short-circuited rotor. Of all more than 20 vector control types known presently, the following are applied most frequently: direct vector control with velocity pickup (VP, direct vector control without VP, indirect vector control with VP and indirect vector control without VP. Despite the fact that the asynchronous-motor indirect vector control without VP is the easiest and most spread, the absence of VP does not allow controlling the motor electromagnetic torque at zero velocity. This is the reason why for electric motor drives of such requirements they utilize the vector control with a velocity transducer. The systems of widest dissemination became the direct and indirect vector control systems with X-axis alignment of the synchronously rotating x–y-coordinate frame along the rotor flux-linkage vector inasmuch as this provides the simplest correlations for controlling variables. Although these two types of vector control are well presented in literature, a number of issues concerning their realization and practical application require further elaboration. These include: the block schemes adequate representation as consisted with the modern realization of vector control and clarification of the analytical expressions for evaluating the regulator parameters.The authors present a technique for evaluating the dynamics of an asynchronous electric motor drive with direct vector control and x-axis alignment along the vector of rotor flux linkage. The article offers a generalized structure of this vector control type with detailed description of its principal blocks: controlling system, frequency converter, and the asynchronous motor.The paper presents a direct vector control simulating model developed in the MatLab environment on the grounds of this structure. The authors illustrate the described technique with the results

  12. The Control of Switched Reluctance Motor in Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Zheng Liu

    2014-05-01

    Full Text Available The control of SRM was discussed: current chopping control, angle position control. This paper presents an inverter circuit and a fuzzy sliding mode control method to minimize the torque fluctuation and noise of the SRM. Based on the experimental results, Using the inverter circuit and fuzzy sliding mode control method can effectively minimize the torque fluctuation and noise of the SRM, For the switched reluctance motor applications in electric vehicles to provide a theoretical basis.

  13. [Surgical treatment of eloquent brain area tumors using neurophysiological mapping of the speech and motor areas and conduction tracts].

    Science.gov (United States)

    Zuev, A A; Korotchenko, E N; Ivanova, D S; Pedyash, N V; Teplykh, B A

    To evaluate the efficacy of intraoperative neurophysiological mapping in removing eloquent brain area tumors (EBATs). Sixty five EBAT patients underwent surgical treatment using intraoperative neurophysiological mapping at the Pirogov National Medical and Surgical Center in the period from 2014 to 2015. On primary neurological examination, 46 (71%) patients were detected with motor deficits of varying severity. Speech disorders were diagnosed in 17 (26%) patients. Sixteen patients with concomitant or isolated lesions of the speech centers underwent awake surgery using the asleep-awake-asleep protocol. Standard neurophysiological monitoring included transcranial stimulation as well as motor and, if necessary, speech mapping. The motor and speech areas were mapped with allowance for the preoperative planning data (obtained with a navigation station) synchronized with functional MRI. In this case, a broader representation of the motor and speech centers was revealed in 12 (19%) patients. During speech mapping, no speech disorders were detected in 7 patients; in 9 patients, stimulation of the cerebral cortex in the intended surgical area induced motor (3 patients), sensory (4), and amnesic (2) aphasia. In the total group, we identified 11 patients in whom the tumor was located near the internal capsule. Upon mapping of the conduction tracts in the internal capsule area, the stimulus strength during tumor resection was gradually decreased from 10 mA to 5 mA. Tumor resection was stopped when responses retained at a stimulus strength of 5 mA, which, when compared to the navigation data, corresponded to a distance of about 5 mm to the internal capsule. Completeness of tumor resection was evaluated (contrast-enhanced MRI) in all patients on the first postoperative day. According to the control MRI data, the tumor was resected totally in 60% of patients, subtotally in 24% of patients, and partially in 16% of patients. In the early postoperative period, the development or

  14. The micro-step motor controller protocol and driver

    International Nuclear Information System (INIS)

    Hong, Kwang Pyo; Lee, Chang Hee; Moon, Myung Kook; Choi, Bung Hun; Choi, Young Hyun; Cheon, Jong Gu

    2004-11-01

    We developed the communication protocol which is a main kernel of motor control firmware program that is used at HANARO neutron spectrometer now. This protocol driver divide into as a 4 group(Serial protocol, DLL, Active-X, Labview driver), so end-user can control the motor control as easily by PC RS232/422 port and have a merits as follows: Support a Low Level/High level driver, Support a Network Connectivity function by using High level Driver, One Server can services many client request. By using this protocol, The End-user can be easily makes a application motor control program and developed another application system program by using several kinds of programming tools under Widows and Linux based operation systems

  15. Direct Torque Control of Matrix Converter Fed Induction Motor Drive

    Directory of Open Access Journals (Sweden)

    JAGADEESAN Karpagam

    2011-10-01

    Full Text Available This paper presents the Direct TorqueControl (DTC of induction motor drive using matrixconverters. DTC is a high performance motor controlscheme with fast torque and flux responses. However,the main disadvantage of conventional DTC iselectromagnetic torque ripple. In this paper, directtorque control for Induction Motors using MatrixConverters is analysed and points out the problem ofthe electromagnetic torque ripple which is one of themost important drawbacks of the Direct TorqueControl. Besides, the matrix converter is a single-stageac-ac power conversion device without dc-link energystorage elements. Matrix converter (MC may becomea good alternative to voltage-source inverter (VSI.This work combines the advantages of the matrixconverter with those of the DTC technique, generatingthe required voltage vectors under unity input powerfactor operation. Simulation results demonstrates theeffectiveness of the torque control.

  16. A brain-computer interface controlled mail client.

    Science.gov (United States)

    Yu, Tianyou; Li, Yuanqing; Long, Jinyi; Wang, Cong

    2013-01-01

    In this paper, we propose a brain-computer interface (BCI) based mail client. This system is controlled by hybrid features extracted from scalp-recorded electroencephalographic (EEG). We emulate the computer mouse by the motor imagery-based mu rhythm and the P300 potential. Furthermore, an adaptive P300 speller is included to provide text input function. With this BCI mail client, users can receive, read, write mails, as well as attach files in mail writing. The system has been tested on 3 subjects. Experimental results show that mail communication with this system is feasible.

  17. Brain infusion of α-synuclein oligomers induces motor and non-motor Parkinson's disease-like symptoms in mice.

    Science.gov (United States)

    Fortuna, Juliana T S; Gralle, Matthias; Beckman, Danielle; Neves, Fernanda S; Diniz, Luan P; Frost, Paula S; Barros-Aragão, Fernanda; Santos, Luís E; Gonçalves, Rafaella A; Romão, Luciana; Zamberlan, Daniele C; Soares, Felix A A; Braga, Carolina; Foguel, Debora; Gomes, Flávia C A; De Felice, Fernanda G; Ferreira, Sergio T; Clarke, Julia R; Figueiredo, Cláudia P

    2017-08-30

    Parkinson's disease (PD) is characterized by motor dysfunction, which is preceded by a number of non-motor symptoms including olfactory deficits. Aggregation of α-synuclein (α-syn) gives rise to Lewy bodies in dopaminergic neurons and is thought to play a central role in PD pathology. However, whether amyloid fibrils or soluble oligomers of α-syn are the main neurotoxic species in PD remains controversial. Here, we performed a single intracerebroventricular (i.c.v.) infusion of α-syn oligomers (α-SYOs) in mice and evaluated motor and non-motor symptoms. Familiar bedding and vanillin essence discrimination tasks showed that α-SYOs impaired olfactory performance of mice, and decreased TH and dopamine levels in the olfactory bulb early after infusion. The olfactory deficit persisted until 45days post-infusion (dpi). α- SYO-infused mice behaved normally in the object recognition and forced swim tests, but showed increased anxiety-like behavior in the open field and elevated plus maze tests 20 dpi. Finally, administration of α-SYOs induced late motor impairment in the pole test and rotarod paradigms, along with reduced TH and dopamine content in the caudate putamen, 45 dpi. Reduced number of TH-positive cells was also seen in the substantia nigra of α-SYO-injected mice compared to control. In conclusion, i.c.v. infusion of α-SYOs recapitulated some of PD-associated non-motor symptoms, such as increased anxiety and olfactory dysfunction, but failed to recapitulate memory impairment and depressive-like behavior typical of the disease. Moreover, α-SYOs i.c.v. administration induced motor deficits and loss of TH and dopamine levels, key features of PD. Results point to α-syn oligomers as the proximal neurotoxins responsible for early non-motor and motor deficits in PD and suggest that the i.c.v. infusion model characterized here may comprise a useful tool for identification of PD novel therapeutic targets and drug screening. Copyright © 2017 Elsevier B.V. All

  18. Interfaz cerebro computador basada en P300 para la comunicación alternativa: estudio de caso en dos adolescentes en situación de discapacidad motora [P300 based Brain Computer Interface for alternative communication: a case study with two teenagers with motor disabilities

    NARCIS (Netherlands)

    Garcia Cossio, E.; Fernandez, C.; Gaviria, M.E.; Palacio, C.; Alvaran, L.; Torres Villa, R.A.

    2011-01-01

    Brain computer interface systems use brain signals to enable the control of external devices, such as: wheelchairs, communicators, neuro-prosthesis, among others; in people with severe motor disabilities. In this study two young men with motor disabilities were trained to learn how to control a

  19. Engineering controllable bidirectional molecular motors based on myosin

    Science.gov (United States)

    Chen, Lu; Nakamura, Muneaki; Schindler, Tony D.; Parker, David; Bryant, Zev

    2012-04-01

    Cytoskeletal motors drive the transport of organelles and molecular cargoes within cells and have potential applications in molecular detection and diagnostic devices. Engineering molecular motors with controllable properties will allow selective perturbation of mechanical processes in living cells and provide optimized device components for tasks such as molecular sorting and directed assembly. Biological motors have previously been modified by introducing activation/deactivation switches that respond to metal ions and other signals. Here, we show that myosin motors can be engineered to reversibly change their direction of motion in response to a calcium signal. Building on previous protein engineering studies and guided by a structural model for the redirected power stroke of myosin VI, we have constructed bidirectional myosins through the rigid recombination of structural modules. The performance of the motors was confirmed using gliding filament assays and single fluorophore tracking. Our strategy, in which external signals trigger changes in the geometry and mechanics of myosin lever arms, should make it possible to achieve spatiotemporal control over a range of motor properties including processivity, stride size and branchpoint turning.

  20. Engineering controllable bidirectional molecular motors based on myosin

    Science.gov (United States)

    Chen, Lu; Nakamura, Muneaki; Schindler, Tony D.; Parker, David; Bryant, Zev

    2012-01-01

    Cytoskeletal motors drive the transport of organelles and molecular cargoes within cells1, and have potential applications in molecular detection and diagnostic devices2,3. Engineering molecular motors with dynamically controllable properties will allow selective perturbation of mechanical processes in living cells, and yield optimized device components for complex tasks such as molecular sorting and directed assembly3. Biological motors have previously been modified by introducing activation/deactivation switches that respond to metal ions4,5 and other signals6. Here we show that myosin motors can be engineered to reversibly change their direction of motion in response to a calcium signal. Building on previous protein engineering studies7–11 and guided by a structural model12 for the redirected power stroke of myosin VI, we constructed bidirectional myosins through the rigid recombination of structural modules. The performance of the motors was confirmed using gliding filament assays and single fluorophore tracking. Our general strategy, in which external signals trigger changes in the geometry and mechanics of myosin lever arms, should enable spatiotemporal control over a range of motor properties including processivity, stride size13, and branchpoint turning14. PMID:22343382

  1. A modern neuroscience approach to chronic spinal pain: combining pain neuroscience education with cognition-targeted motor control training.

    Science.gov (United States)

    Nijs, Jo; Meeus, Mira; Cagnie, Barbara; Roussel, Nathalie A; Dolphens, Mieke; Van Oosterwijck, Jessica; Danneels, Lieven

    2014-05-01

    Chronic spinal pain (CSP) is a severely disabling disorder, including nontraumatic chronic low back and neck pain, failed back surgery, and chronic whiplash-associated disorders. Much of the current therapy is focused on input mechanisms (treating peripheral elements such as muscles and joints) and output mechanisms (addressing motor control), while there is less attention to processing (central) mechanisms. In addition to the compelling evidence for impaired motor control of spinal muscles in patients with CSP, there is increasing evidence that central mechanisms (ie, hyperexcitability of the central nervous system and brain abnormalities) play a role in CSP. Hence, treatments for CSP should address not only peripheral dysfunctions but also the brain. Therefore, a modern neuroscience approach, comprising therapeutic pain neuroscience education followed by cognition-targeted motor control training, is proposed. This perspective article explains why and how such an approach to CSP can be applied in physical therapist practice.

  2. Design and Comparison Direct Torque Control Techniques for Induction Motors

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Kazmierkowski, Marian P.; Zelechowski, Marcin

    2005-01-01

    In this paper a comparison of two significant control methods of induction motor are presented. The first one is a classical Direct Torque and Flux Control (DTC) and is compared with a scheme, which uses Space Vector Modulator (DTC-SVM). A comparison in respect to dynamic and steady state...

  3. Nonlinear control of permanent magnet synchronous motor driving a ...

    African Journals Online (AJOL)

    This paper presents a non-linear control of permanent magnet synchronous motor (PMSM) fed by a PWM voltage source inverter. To improve the performance of this control technique, the input-output linearization technique is proposed for a system driving a mechanical load with two masses. In order to ensure a steady ...

  4. Pneumatic motor speed control by trajectory tracking fuzzy logic

    Indian Academy of Sciences (India)

    In this study, trajectory tracking fuzzy logic controller (TTFLC) is proposed for the speed control of a pneumatic motor (PM). A third order trajectory is defined to determine the trajectory function that has to be tracked by the PM speed. Genetic algorithm (GA) is used to find the TTFLC boundary values of membership functions ...

  5. Understanding the relationship between brain and upper limb function in children with unilateral motor impairments: A multimodal approach

    NARCIS (Netherlands)

    Weinstein, M.; Green, D.; Rudisch, J.; Zielinski, I.M.; Benthem-Muñiz, M.; Jongsma, M.L.A.; McLellend, V.; Steenbergen, B.; Shiran, S.I.; Ben Bashat, D.; Barker, G.J.

    2018-01-01

    Atypical brain development and early brain injury have profound and long lasting impact on the development, skill acquisition, and subsequent independence of a child. Heterogeneity is present at the brain level and at the motor level; particularly with respect to phenomena of bilateral activation

  6. Noninvasive brain stimulation in neurorehabilitation: Local and distant effects for motor recovery

    Directory of Open Access Journals (Sweden)

    Sook-Lei eLiew

    2014-06-01

    Full Text Available Noninvasive brain stimulation (NIBS may enhance motor recovery after neurological injury through the causal induction of plasticity processes. Neurological injury, such as stroke, often results in serious long-term physical disabilities, and despite intensive therapy, a large majority of brain injury survivors fail to regain full motor function. Emerging research suggests that NIBS techniques, such as transcranial magnetic (TMS and direct current (tDCS stimulation, in association with customarily used neurorehabilitative treatments, may enhance motor recovery. This paper provides a general review on TMS and tDCS paradigms, the mechanisms by which they operate and the stimulation techniques used in neurorehabilitation, specifically stroke. TMS and tDCS influence regional neural activity underlying the stimulation location and also distant interconnected network activity throughout the brain. We discuss recent studies that document NIBS effects on global brain activity measured with various neuroimaging techniques, which help to characterize better strategies for more accurate NIBS stimulation. These rapidly growing areas of inquiry may hold potential for improving the effectiveness of NIBS-based interventions for clinical rehabilitation.

  7. Cognitive and Neurophysiological Effects of Non-invasive Brain Stimulation in Stroke Patients after Motor Rehabilitation.

    Science.gov (United States)

    D'Agata, Federico; Peila, Elena; Cicerale, Alessandro; Caglio, Marcella M; Caroppo, Paola; Vighetti, Sergio; Piedimonte, Alessandro; Minuto, Alice; Campagnoli, Marcello; Salatino, Adriana; Molo, Maria T; Mortara, Paolo; Pinessi, Lorenzo; Massazza, Giuseppe

    2016-01-01

    The primary aim of this study was to evaluate and compare the effectiveness of two specific Non-Invasive Brain Stimulation (NIBS) paradigms, the repetitive Transcranial Magnetic Stimulation (rTMS), and transcranial Direct Current Stimulation (tDCS), in the upper limb rehabilitation of patients with stroke. Short and long term outcomes (after 3 and 6 months, respectively) were evaluated. We measured, at multiple time points, the manual dexterity using a validated clinical scale (ARAT), electroencephalography auditory event related potentials, and neuropsychological performances in patients with chronic stroke of middle severity. Thirty four patients were enrolled and randomized. The intervention group was treated with a NIBS protocol longer than usual, applying a second cycle of stimulation, after a washout period, using different techniques in the two cycles (rTMS/tDCS). We compared the results with a control group treated with sham stimulation. We split the data analysis into three studies. In this first study we examined if a cumulative effect was clinically visible. In the second study we compared the effects of the two techniques. In the third study we explored if patients with minor cognitive impairment have most benefit from the treatment and if cognitive and motor outcomes were correlated. We found that the impairment in some cognitive domains cannot be considered an exclusion criterion for rehabilitation with NIBS. ERP improved, related to cognitive and attentional processes after stimulation on the motor cortex, but transitorily. This effect could be linked to the restoration of hemispheric balance or by the effects of distant connections. In our study the effects of the two NIBS were comparable, with some advantages using tDCS vs. rTMS in stroke rehabilitation. Finally we found that more than one cycle (2-4 weeks), spaced out by washout periods, should be used, only in responder patients, to obtain clinical relevant results.

  8. Effect of instructive visual stimuli on neurofeedback training for motor imagery-based brain-computer interface.

    Science.gov (United States)

    Kondo, Toshiyuki; Saeki, Midori; Hayashi, Yoshikatsu; Nakayashiki, Kosei; Takata, Yohei

    2015-10-01

    Event-related desynchronization (ERD) of the electroencephalogram (EEG) from the motor cortex is associated with execution, observation, and mental imagery of motor tasks. Generation of ERD by motor imagery (MI) has been widely used for brain-computer interfaces (BCIs) linked to neuroprosthetics and other motor assistance devices. Control of MI-based BCIs can be acquired by neurofeedback training to reliably induce MI-associated ERD. To develop more effective training conditions, we investigated the effect of static and dynamic visual representations of target movements (a picture of forearms or a video clip of hand grasping movements) during the BCI neurofeedback training. After 4 consecutive training days, the group that performed MI while viewing the video showed significant improvement in generating MI-associated ERD compared with the group that viewed the static image. This result suggests that passively observing the target movement during MI would improve the associated mental imagery and enhance MI-based BCIs skills. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Discrete Current Control Strategy of Permanent Magnet Synchronous Motors

    Directory of Open Access Journals (Sweden)

    Yan Dong

    2013-01-01

    Full Text Available A control strategy of permanent magnet synchronous motors (PMSMs, which is different from the traditional vector control (VC and direct torque control (DTC, is proposed. Firstly, the circular rotating magnetic field is analyzed on the simplified model and discredited into stepping magnetic field. The stepping magnetomotive force will drive the rotor to run as the stepping motor. Secondly, the stator current orientation is used to build the control model instead of rotor flux orientation. Then, the discrete current control strategy is set and adopted in positioning control. Three methods of the strategy are simulated in computer and tested on the experiment platform of PMSM. The control precision is also verified through the experiment.

  10. Rapid Control Prototyping Plataform for Didactic Plant Motor DC

    Directory of Open Access Journals (Sweden)

    Cristian Bazán-Orobio

    2013-06-01

    Full Text Available In this paper a design, implementation and validation of a Rapid Control Prototype platform for a plant based on a DC motor is proposed. This low-cost prototype provides of an electronic card (with a motor DC and sensors manipulated by PC with free software tools using Linux, Scilab / Scicos and RTAI-Lab. This RCP System allows developing speed -position control trainings by using different types of PID industrial controllers with anti – wind up and bump less transfer schemes. We develop a speed control application structured in four steps: identification, controller design, simulation and real time control, where there are pedagogical advantages of a platform that not only allows simulation but also real-time control of a plant.

  11. Higher-order Brain Areas Associated with Real-time Functional MRI Neurofeedback Training of the Somato-motor Cortex.

    Science.gov (United States)

    Auer, Tibor; Dewiputri, Wan Ilma; Frahm, Jens; Schweizer, Renate

    2018-05-15

    Neurofeedback (NFB) allows subjects to learn self-regulation of neuronal brain activation based on information about the ongoing activation. The implementation of real-time functional magnetic resonance imaging (rt-fMRI) for NFB training now facilitates the investigation into underlying processes. Our study involved 16 control and 16 training right-handed subjects, the latter performing an extensive rt-fMRI NFB training using motor imagery. A previous analysis focused on the targeted primary somato-motor cortex (SMC). The present study extends the analysis to the supplementary motor area (SMA), the next higher brain area within the hierarchy of the motor system. We also examined transfer-related functional connectivity using a whole-volume psycho-physiological interaction (PPI) analysis to reveal brain areas associated with learning. The ROI analysis of the pre- and post-training fMRI data for motor imagery without NFB (transfer) resulted in a significant training-specific increase in the SMA. It could also be shown that the contralateral SMA exhibited a larger increase than the ipsilateral SMA in the training and the transfer runs, and that the right-hand training elicited a larger increase in the transfer runs than the left-hand training. The PPI analysis revealed a training-specific increase in transfer-related functional connectivity between the left SMA and frontal areas as well as the anterior midcingulate cortex (aMCC) for right- and left-hand trainings. Moreover, the transfer success was related with training-specific increase in functional connectivity between the left SMA and the target area SMC. Our study demonstrates that NFB training increases functional connectivity with non-targeted brain areas. These are associated with the training strategy (i.e., SMA) as well as with learning the NFB skill (i.e., aMCC and frontal areas). This detailed description of both the system to be trained and the areas involved in learning can provide valuable information

  12. 75 FR 43975 - California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Truck Idling...

    Science.gov (United States)

    2010-07-27

    ... standards) for the control of emissions from new motor vehicles or new motor vehicle engines prior to March... approval relating to the control of emissions from any new motor vehicle or new motor vehicle engine as... relating to the control of emissions from new nonroad spark-ignition engines smaller than 50 horsepower...

  13. A synergy-based hand control is encoded in human motor cortical areas

    Science.gov (United States)

    Leo, Andrea; Handjaras, Giacomo; Bianchi, Matteo; Marino, Hamal; Gabiccini, Marco; Guidi, Andrea; Scilingo, Enzo Pasquale; Pietrini, Pietro; Bicchi, Antonio; Santello, Marco; Ricciardi, Emiliano

    2016-01-01

    How the human brain controls hand movements to carry out different tasks is still debated. The concept of synergy has been proposed to indicate functional modules that may simplify the control of hand postures by simultaneously recruiting sets of muscles and joints. However, whether and to what extent synergic hand postures are encoded as such at a cortical level remains unknown. Here, we combined kinematic, electromyography, and brain activity measures obtained by functional magnetic resonance imaging while subjects performed a variety of movements towards virtual objects. Hand postural information, encoded through kinematic synergies, were represented in cortical areas devoted to hand motor control and successfully discriminated individual grasping movements, significantly outperforming alternative somatotopic or muscle-based models. Importantly, hand postural synergies were predicted by neural activation patterns within primary motor cortex. These findings support a novel cortical organization for hand movement control and open potential applications for brain-computer interfaces and neuroprostheses. DOI: http://dx.doi.org/10.7554/eLife.13420.001 PMID:26880543

  14. Active Fault Tolerant Control for Ultrasonic Piezoelectric Motor

    Science.gov (United States)

    Boukhnifer, Moussa

    2012-07-01

    Ultrasonic piezoelectric motor technology is an important system component in integrated mechatronics devices working on extreme operating conditions. Due to these constraints, robustness and performance of the control interfaces should be taken into account in the motor design. In this paper, we apply a new architecture for a fault tolerant control using Youla parameterization for an ultrasonic piezoelectric motor. The distinguished feature of proposed controller architecture is that it shows structurally how the controller design for performance and robustness may be done separately which has the potential to overcome the conflict between performance and robustness in the traditional feedback framework. A fault tolerant control architecture includes two parts: one part for performance and the other part for robustness. The controller design works in such a way that the feedback control system will be solely controlled by the proportional plus double-integral PI2 performance controller for a nominal model without disturbances and H∞ robustification controller will only be activated in the presence of the uncertainties or an external disturbances. The simulation results demonstrate the effectiveness of the proposed fault tolerant control architecture.

  15. Motor skill learning, retention, and control deficits in Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Lisa Katharina Pendt

    Full Text Available Parkinson's disease, which affects the basal ganglia, is known to lead to various impairments of motor control. Since the basal ganglia have also been shown to be involved in learning processes, motor learning has frequently been investigated in this group of patients. However, results are still inconsistent, mainly due to skill levels and time scales of testing. To bridge across the time scale problem, the present study examined de novo skill learning over a long series of practice sessions that comprised early and late learning stages as well as retention. 19 non-demented, medicated, mild to moderate patients with Parkinson's disease and 19 healthy age and gender matched participants practiced a novel throwing task over five days in a virtual environment where timing of release was a critical element. Six patients and seven control participants came to an additional long-term retention testing after seven to nine months. Changes in task performance were analyzed by a method that differentiates between three components of motor learning prominent in different stages of learning: Tolerance, Noise and Covariation. In addition, kinematic analysis related the influence of skill levels as affected by the specific motor control deficits in Parkinson patients to the process of learning. As a result, patients showed similar learning in early and late stages compared to the control subjects. Differences occurred in short-term retention tests; patients' performance constantly decreased after breaks arising from poorer release timing. However, patients were able to overcome the initial timing problems within the course of each practice session and could further improve their throwing performance. Thus, results demonstrate the intact ability to learn a novel motor skill in non-demented, medicated patients with Parkinson's disease and indicate confounding effects of motor control deficits on retention performance.

  16. Morphological features of the neonatal brain support development of subsequent cognitive, language, and motor abilities.

    Science.gov (United States)

    Spann, Marisa N; Bansal, Ravi; Rosen, Tove S; Peterson, Bradley S

    2014-09-01

    Knowledge of the role of brain maturation in the development of cognitive abilities derives primarily from studies of school-age children to adults. Little is known about the morphological features of the neonatal brain that support the subsequent development of abilities in early childhood, when maturation of the brain and these abilities are the most dynamic. The goal of our study was to determine whether brain morphology during the neonatal period supports early cognitive development through 2 years of age. We correlated morphological features of the cerebral surface assessed using deformation-based measures (surface distances) of high-resolution MRI scans for 33 healthy neonates, scanned between the first to sixth week of postmenstrual life, with subsequent measures of their motor, language, and cognitive abilities at ages 6, 12, 18, and 24 months. We found that morphological features of the cerebral surface of the frontal, mesial prefrontal, temporal, and occipital regions correlated with subsequent motor scores, posterior parietal regions correlated with subsequent language scores, and temporal and occipital regions correlated with subsequent cognitive scores. Measures of the anterior and middle portions of the cingulate gyrus correlated with scores across all three domains of ability. Most of the significant findings were inverse correlations located bilaterally in the brain. The inverse correlations may suggest either that a more protracted morphological maturation or smaller local volumes of neonatal brain tissue supports better performance on measures of subsequent motor, language, and cognitive abilities throughout the first 2 years of postnatal life. The correlations of morphological measures of the cingulate with measures of performance across all domains of ability suggest that the cingulate supports a broad range of skills in infancy and early childhood, similar to its functions in older children and adults. Copyright © 2014 Wiley Periodicals, Inc.

  17. Chaotic operation and chaos control of travelling wave ultrasonic motor.

    Science.gov (United States)

    Shi, Jingzhuo; Zhao, Fujie; Shen, Xiaoxi; Wang, Xiaojie

    2013-08-01

    The travelling wave ultrasonic motor, which is a nonlinear dynamic system, has complex chaotic phenomenon with some certain choices of system parameters and external inputs, and its chaotic characteristics have not been studied until now. In this paper, the preliminary study of the chaos phenomenon in ultrasonic motor driving system has been done. The experiment of speed closed-loop control is designed to obtain several groups of time sampling data sequence of the amplitude of driving voltage, and phase-space reconstruction is used to analyze the chaos characteristics of these time sequences. The largest Lyapunov index is calculated and the result is positive, which shows that the travelling wave ultrasonic motor has chaotic characteristics in a certain working condition Then, the nonlinear characteristics of travelling wave ultrasonic motor are analyzed which includes Lyapunov exponent map, the bifurcation diagram and the locus of voltage relative to speed based on the nonlinear chaos model of a travelling wave ultrasonic motor. After that, two kinds of adaptive delay feedback controllers are designed in this paper to control and suppress chaos in USM speed control system. Simulation results show that the method can control unstable periodic orbits, suppress chaos in USM control system. Proportion-delayed feedback controller was designed following and arithmetic of fuzzy logic was used to adaptively adjust the delay time online. Simulation results show that this method could fast and effectively change the chaos movement into periodic or fixed-point movement and make the system enter into stable state from chaos state. Finally the chaos behavior was controlled. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Factors of Influence on the Performance of a Short-Latency Non-Invasive Brain Switch: Evidence in Healthy Individuals and Implication for Motor Function Rehabilitation

    Directory of Open Access Journals (Sweden)

    Ren eXu

    2016-01-01

    Full Text Available Brain-computer interfacing (BCI has recently been applied as a rehabilitation approach for patients with motor disorders, such as stroke. In these closed-loop applications, a brain switch detects the motor intention from brain signals, e.g. scalp EEG, and triggers a neuroprosthetic device, either to deliver sensory feedback or to mimic real movements, thus re-establishing the compromised sensory-motor control loop and promoting neural plasticity. In this context, single trial detection of motor intention with short latency is a prerequisite. The performance of the event detection from EEG recordings is mainly determined by three factors: the type of motor imagery (e.g., repetitive, ballistic, the frequency band (or signal modality used for discrimination (e.g., alpha, beta, gamma, and MRCP, i.e. movement-related cortical potential, and the processing technique (e.g., time-series analysis, sub-band power estimation. In this study, we investigated single trial EEG traces during movement imagination on healthy individuals, and provided a comprehensive analysis of the performance of a short-latency brain switch when varying these three factors. The morphological investigation showed a cross-subject consistency of a prolonged negative phase in MRCP, and a delayed beta rebound in sensory-motor rhythms during repetitive tasks. The detection performance had the greatest accuracy when using ballistic MRCP with time-series analysis. In this case, the true positive rate was ~70% for a detection latency of ~200 ms. The results presented here are of practical relevance for designing BCI systems for motor function rehabilitation.

  19. Flux-weakening control methods for hybrid excitation synchronous motor

    Directory of Open Access Journals (Sweden)

    Mingming Huang

    2015-09-01

    Full Text Available The hybrid excitation synchronous motor (HESM, which aim at combining the advantages of permanent magnet motor and wound excitation motor, have the characteristics of low-speed high-torque hill climbing and wide speed range. Firstly, a new kind of HESM is presented in the paper, and its structure and mathematical model are illustrated. Then, based on a space voltage vector control, a novel flux-weakening method for speed adjustment in the high speed region is presented. The unique feature of the proposed control method is that the HESM driving system keeps the q-axis back-EMF components invariable during the flux-weakening operation process. Moreover, a copper loss minimization algorithm is adopted to reduce the copper loss of the HESM in the high speed region. Lastly, the proposed method is validated by the simulation and the experimental results.

  20. Time Course of Brain Network Reconfiguration Supporting Inhibitory Control.

    Science.gov (United States)

    Popov, Tzvetan; Westner, Britta U; Silton, Rebecca L; Sass, Sarah M; Spielberg, Jeffrey M; Rockstroh, Brigitte; Heller, Wendy; Miller, Gregory A

    2018-05-02

    Hemodynamic research has recently clarified key nodes and links in brain networks implementing inhibitory control. Although fMRI methods are optimized for identifying the structure of brain networks, the relatively slow temporal course of fMRI limits the ability to characterize network operation. The latter is crucial for developing a mechanistic understanding of how brain networks shift dynamically to support inhibitory control. To address this critical gap, we applied spectrally resolved Granger causality (GC) and random forest machine learning tools to human EEG data in two large samples of adults (test sample n = 96, replication sample n = 237, total N = 333, both sexes) who performed a color-word Stroop task. Time-frequency analysis confirmed that recruitment of inhibitory control accompanied by slower behavioral responses was related to changes in theta and alpha/beta power. GC analyses revealed directionally asymmetric exchanges within frontal and between frontal and parietal brain areas: top-down influence of superior frontal gyrus (SFG) over both dorsal ACC (dACC) and inferior frontal gyrus (IFG), dACC control over middle frontal gyrus (MFG), and frontal-parietal exchanges (IFG, precuneus, MFG). Predictive analytics confirmed a combination of behavioral and brain-derived variables as the best set of predictors of inhibitory control demands, with SFG theta bearing higher classification importance than dACC theta and posterior beta tracking the onset of behavioral response. The present results provide mechanistic insight into the biological implementation of a psychological phenomenon: inhibitory control is implemented by dynamic routing processes during which the target response is upregulated via theta-mediated effective connectivity within key PFC nodes and via beta-mediated motor preparation. SIGNIFICANCE STATEMENT Hemodynamic neuroimaging research has recently clarified regional structures in brain networks supporting inhibitory control. However, due to

  1. Motor control and the management of musculoskeletal dysfunction.

    Science.gov (United States)

    van Vliet, Paulette M; Heneghan, Nicola R

    2006-08-01

    This paper aims to develop understanding of three important motor control issues--feedforward mechanisms, cortical plasticity and task-specificity and assess the implications for musculoskeletal practice. A model of control for the reach-to-grasp movement illustrates how the central nervous system integrates sensorimotor processes to control complex movements. Feedforward mechanisms, an essential element of motor control, are altered in neurologically intact patients with chronic neck pain and low back pain. In healthy subjects, cortical mapping studies using transcranial magnetic stimulation have demonstrated that neural pathways adapt according to what and how much is practised. Neuroplasticity has also been demonstrated in a number of musculoskeletal conditions, where cortical maps are altered compared to normal. Behavioural and neurophysiological studies indicate that environmental and task constraints such as the goal of the task and an object's shape and size, are determinants of the motor schema for reaching and other movements. Consideration of motor control issues as well as signs and symptoms, may facilitate management of musculoskeletal conditions and improve outcome. Practice of entire everyday tasks at an early stage and systematic variation of the task is recommended. Training should be directed with the aim of re-educating feedforward mechanisms where necessary and the amount of practice should be sufficient to cause changes in cortical activity.

  2. EOG Controlled Motorized Wheelchair for Disabled Persons

    OpenAIRE

    A. Naga Rajesh; S. Chandralingam; T. Anjaneyulu; K. Satyanarayana

    2014-01-01

    Assistive robotics are playing a vital role in advancing the quality of life for disable people. There exist wide range of systems that can control and guide autonomous mobile robots. The objective of the control system is to guide an autonomous mobile robot using the movement of eyes by means of EOG signal. The EOG signal is acquired using Ag/AgCl electrodes and this signal is processed by a microcontroller unit to calculate the eye gaze direction. Then according to the guidance control stra...

  3. Development of a Novel Motor Imagery Control Technique and Application in a Gaming Environment

    OpenAIRE

    Li, Ting; Zhang, Jinhua; Xue, Tao; Wang, Baozeng

    2017-01-01

    We present a methodology for a hybrid brain-computer interface (BCI) system, with the recognition of motor imagery (MI) based on EEG and blink EOG signals. We tested the BCI system in a 3D Tetris and an analogous 2D game playing environment. To enhance player’s BCI control ability, the study focused on feature extraction from EEG and control strategy supporting Game-BCI system operation. We compared the numerical differences between spatial features extracted with common spatial pattern (CSP)...

  4. Effect of visual feedback on brain activation during motor tasks: an FMRI study.

    Science.gov (United States)

    Noble, Jeremy W; Eng, Janice J; Boyd, Lara A

    2013-07-01

    This study examined the effect of visual feedback and force level on the neural mechanisms responsible for the performance of a motor task. We used a voxel-wise fMRI approach to determine the effect of visual feedback (with and without) during a grip force task at 35% and 70% of maximum voluntary contraction. Two areas (contralateral rostral premotor cortex and putamen) displayed an interaction between force and feedback conditions. When the main effect of feedback condition was analyzed, higher activation when visual feedback was available was found in 22 of the 24 active brain areas, while the two other regions (contralateral lingual gyrus and ipsilateral precuneus) showed greater levels of activity when no visual feedback was available. The results suggest that there is a potentially confounding influence of visual feedback on brain activation during a motor task, and for some regions, this is dependent on the level of force applied.

  5. Performance variation in motor imagery brain-computer interface: a brief review.

    Science.gov (United States)

    Ahn, Minkyu; Jun, Sung Chan

    2015-03-30

    Brain-computer interface (BCI) technology has attracted significant attention over recent decades, and has made remarkable progress. However, BCI still faces a critical hurdle, in that performance varies greatly across and even within subjects, an obstacle that degrades the reliability of BCI systems. Understanding the causes of these problems is important if we are to create more stable systems. In this short review, we report the most recent studies and findings on performance variation, especially in motor imagery-based BCI, which has found that low-performance groups have a less-developed brain network that is incapable of motor imagery. Further, psychological and physiological states influence performance variation within subjects. We propose a possible strategic approach to deal with this variation, which may contribute to improving the reliability of BCI. In addition, the limitations of current work and opportunities for future studies are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. A square root ensemble Kalman filter application to a motor-imagery brain-computer interface.

    Science.gov (United States)

    Kamrunnahar, M; Schiff, S J

    2011-01-01

    We here investigated a non-linear ensemble Kalman filter (SPKF) application to a motor imagery brain computer interface (BCI). A square root central difference Kalman filter (SR-CDKF) was used as an approach for brain state estimation in motor imagery task performance, using scalp electroencephalography (EEG) signals. Healthy human subjects imagined left vs. right hand movements and tongue vs. bilateral toe movements while scalp EEG signals were recorded. Offline data analysis was conducted for training the model as well as for decoding the imagery movements. Preliminary results indicate the feasibility of this approach with a decoding accuracy of 78%-90% for the hand movements and 70%-90% for the tongue-toes movements. Ongoing research includes online BCI applications of this approach as well as combined state and parameter estimation using this algorithm with different system dynamic models.

  7. Motor control assessment of community-dwelling older adults with depressive symptoms

    Directory of Open Access Journals (Sweden)

    Lucas Eduardo Antunes Bicalho

    2017-12-01

    Full Text Available Abstract AIMSThe purpose of this study was to investigate how depressive symptoms mediate different motor control requirements in elderlies and to assess the concurring effects fomented by the interaction between aging and depressive symptoms, providing indirect measures of brain functionality. METHODS Sixty-eight elderlies were paired in terms of age and gender and were equally distributed into depressed and nondepressed groups, according to their score on the Beck Depression Questionnaire. The participants performed the Grooved Pegboard Test placing and withdrawing pegs while execution time and error rate were measured. RESULTS This investigation revealed that depressive symptoms exert a broad effect upon motor control, although that the symptom intensity, as well as the interaction between aging and depression intensity, were exclusively correlated with withdrawal task, suggesting that there is a greater effect upon motor acts with higher frontal lobe requirements. CONCLUSION The discrimination of motor control aspects provides a valuable contribution for the understanding of the underlying neurophysiology of the interaction between aging and depression as it represents an indirect measure of cerebral dysfunction. Further, these findings may still have clinical implications, as they can promote more rational approaches to the elaboration of preventive measures that help maintain the functional capability of depressed elderlies.

  8. Localization of Brain Electrical Activity Sources and Hemodynamic Activity Foci during Motor Imagery

    Czech Academy of Sciences Publication Activity Database

    Frolov, A. A.; Húsek, Dušan; Mokienko, O.; Bobrov, P.; Chernikova, L.; Konovalov, R.

    2014-01-01

    Roč. 40, č. 3 (2014), s. 273-283 ISSN 0362-1197 Grant - others:GA MŠk(CZ) ED1.1.00/02.0070; GA MŠk(CZ) EE.2.3.20.0073 Program:ED Institutional support: RVO:67985807 Keywords : brain computer interface * independent component analysis * EEG pattern classification * motor imagery * inverse EEG problem Subject RIV: IN - Informatics, Computer Science

  9. Effector-independent brain activity during motor imagery of the upper and lower limbs: an fMRI study.

    Science.gov (United States)

    Mizuguchi, Nobuaki; Nakata, Hiroki; Kanosue, Kazuyuki

    2014-10-03

    We utilized functional magnetic resonance imaging (fMRI) to evaluate the common brain region of motor imagery for the right and left upper and lower limbs. The subjects were instructed to repeatedly imagined extension and flexion of the right or left hands/ankles. Brain regions, which included the supplemental motor area (SMA), premotor cortex and parietal cortex, were activated during motor imagery. Conjunction analysis revealed that the left SMA and inferior frontal gyrus (IFG)/ventral premotor cortex (vPM) were commonly activated with motor imagery of the right hand, left hand, right foot, and left foot. This result suggests that these brain regions are activated during motor imagery in an effector independent manner. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Piano training in youths with hand motor impairments after damage to the developing brain

    Science.gov (United States)

    Lampe, Renée; Thienel, Anna; Mitternacht, Jürgen; Blumenstein, Tobias; Turova, Varvara; Alves-Pinto, Ana

    2015-01-01

    Damage to the developing brain may lead to impairment of the hand motor function and negatively impact on patients’ quality of life. Development of manual dexterity and finger and hand motor function may be promoted by learning to play the piano. The latter brings together music with the intensive training of hand coordination and fine finger mobility. We investigated if learning to play the piano helped to improve hand motor skills in 18 youths with hand motor disorders resulting from damage during early brain development. Participants trained 35–40 minutes twice a week for 18 months with a professional piano teacher. With the use of a Musical Instrument Digital Interface piano, the uniformity of finger strokes could be objectively assessed from the timing of keystrokes. The analysis showed a significant improvement in the uniformity of keystrokes during the training. Furthermore, the youths showed strong motivation and engagement during the study. This is nevertheless an open study, and further studies remain needed to exclude effects of growth and concomitant therapies on the improvements observed and clarify which patients will more likely benefit from learning to play the piano. PMID:26345312

  11. Controller Design for Direct Torque Controlled Space Vector Modulated (DTC-SVM) Induction Motor Drives

    DEFF Research Database (Denmark)

    Zelechowski, M.; Kazmierkowski, M.P.; Blaabjerg, Frede

    2005-01-01

    In this paper two different methods of PI controllers for direct torque controlled-space vector modulated induction motor drives have been studied. The first one is simple method based only on symmetric optimum criterion. The second approach takes into account the full model of induction motor in...

  12. Simple Approach For Induction Motor Control Using Reconfigurable Hardware

    Directory of Open Access Journals (Sweden)

    József VÁSÁRHELYI

    2002-12-01

    Full Text Available The paper deals with rotor-field-oriented vector control structures for the induction motor drives fed by the so-called tandem frequency converter. It is composed of two different types of DC-link converters connected in parallel arrangement. The larger-power one has current-source character and is operating synchronized in time and in amplitude with the stator currents. The other one has voltage-source character and it is the actuator of the motor control system. The drive is able to run also with partial-failed tandem converter, if the control strategy corresponds to the actual operating mode. A reconfigurable hardware implemented in configurable logic cells ensures the changing of the vector-control structure. The proposed control schemes were tested by simulation based on Matlab-Simulink model.

  13. Enhanced pid vs model predictive control applied to bldc motor

    Science.gov (United States)

    Gaya, M. S.; Muhammad, Auwal; Aliyu Abdulkadir, Rabiu; Salim, S. N. S.; Madugu, I. S.; Tijjani, Aminu; Aminu Yusuf, Lukman; Dauda Umar, Ibrahim; Khairi, M. T. M.

    2018-01-01

    BrushLess Direct Current (BLDC) motor is a multivariable and highly complex nonlinear system. Variation of internal parameter values with environment or reference signal increases the difficulty in controlling the BLDC effectively. Advanced control strategies (like model predictive control) often have to be integrated to satisfy the control desires. Enhancing or proper tuning of a conventional algorithm results in achieving the desired performance. This paper presents a performance comparison of Enhanced PID and Model Predictive Control (MPC) applied to brushless direct current motor. The simulation results demonstrated that the PSO-PID is slightly better than the PID and MPC in tracking the trajectory of the reference signal. The proposed scheme could be useful algorithms for the system.

  14. Effective and Robust Generalized Predictive Speed Control of Induction Motor

    Directory of Open Access Journals (Sweden)

    Patxi Alkorta

    2013-01-01

    Full Text Available This paper presents and validates a new proposal for effective speed vector control of induction motors based on linear Generalized Predictive Control (GPC law. The presented GPC-PI cascade configuration simplifies the design with regard to GPC-GPC cascade configuration, maintaining the advantages of the predictive control algorithm. The robust stability of the closed loop system is demonstrated by the poles placement method for several typical cases of uncertainties in induction motors. The controller has been tested using several simulations and experiments and has been compared with Proportional Integral Derivative (PID and Sliding Mode (SM control schemes, obtaining outstanding results in speed tracking even in the presence of parameter uncertainties, unknown load disturbance, and measurement noise in the loop signals, suggesting its use in industrial applications.

  15. Position Control of Switched Reluctance Motor Using Super Twisting Algorithm

    Directory of Open Access Journals (Sweden)

    Muhammad Rafiq Mufti

    2016-01-01

    Full Text Available The inherent problem of chattering in traditional sliding mode control is harmful for practical application of control system. This paper pays a considerable attention to a chattering-free control method, that is, higher-order sliding mode (super twisting algorithm. The design of a position controller for switched reluctance motor is presented and its stability is assured using Lyapunov stability theorem. In order to highlight the advantages of higher-order sliding mode controller (HOSMC, a classical first-order sliding mode controller (FOSMC is also applied to the same system and compared. The simulation results reflect the effectiveness of the proposed technique.

  16. A Wearable Channel Selection-Based Brain-Computer Interface for Motor Imagery Detection.

    Science.gov (United States)

    Lo, Chi-Chun; Chien, Tsung-Yi; Chen, Yu-Chun; Tsai, Shang-Ho; Fang, Wai-Chi; Lin, Bor-Shyh

    2016-02-06

    Motor imagery-based brain-computer interface (BCI) is a communication interface between an external machine and the brain. Many kinds of spatial filters are used in BCIs to enhance the electroencephalography (EEG) features related to motor imagery. The approach of channel selection, developed to reserve meaningful EEG channels, is also an important technique for the development of BCIs. However, current BCI systems require a conventional EEG machine and EEG electrodes with conductive gel to acquire multi-channel EEG signals and then transmit these EEG signals to the back-end computer to perform the approach of channel selection. This reduces the convenience of use in daily life and increases the limitations of BCI applications. In order to improve the above issues, a novel wearable channel selection-based brain-computer interface is proposed. Here, retractable comb-shaped active dry electrodes are designed to measure the EEG signals on a hairy site, without conductive gel. By the design of analog CAR spatial filters and the firmware of EEG acquisition module, the function of spatial filters could be performed without any calculation, and channel selection could be performed in the front-end device to improve the practicability of detecting motor imagery in the wearable EEG device directly or in commercial mobile phones or tablets, which may have relatively low system specifications. Finally, the performance of the proposed BCI is investigated, and the experimental results show that the proposed system is a good wearable BCI system prototype.

  17. Gait variability and motor control in people with knee osteoarthritis

    DEFF Research Database (Denmark)

    Alkjaer, Tine; Raffalt, Peter C; Dalsgaard, Helle

    2015-01-01

    fluctuation analysis. The motor control was assessed by the soleus (SO) Hoffmann (H)-reflex modulation and muscle co-activation during walking. The results showed no statistically significant mean group differences in any of the gait variability measures or muscle co-activation levels. The SO H...

  18. Fuzzy sliding mode controller for doubly fed induction motor speed ...

    African Journals Online (AJOL)

    The use of the nonlinear fuzzy sliding mode method provides very good performance for motor operation and robustness of the control law despite the external/internal perturbations. The chattering effects is eliminated by a particular function "sat" that presents a serious problem to applications of variable structure systems.

  19. Fluid logic control circuit operates nutator actuator motor

    Science.gov (United States)

    1966-01-01

    Fluid logic control circuit operates a pneumatic nutator actuator motor. It has no moving parts and consists of connected fluid interaction devices. The operation of this circuit demonstrates the ability of fluid interaction devices to operate in a complex combination of series and parallel logic sequence.

  20. performance characteristics of an armature voltage controlled dc motor

    African Journals Online (AJOL)

    Dr Obe

    obtained by digital computer analysis. The results show that closed loop operation, with appropriate control ... Using digital computer analysis, the driver characteristics of a test motor is investigated. In the closed loop ... system circuit failure especially with respect to the semiconductor devices that may be used in varying ...

  1. Motor impairments related to brain injury timing in early hemiparesis. Part II: abnormal upper extremity joint torque synergies.

    Science.gov (United States)

    Sukal-Moulton, Theresa; Krosschell, Kristin J; Gaebler-Spira, Deborah J; Dewald, Julius P A

    2014-01-01

    Extensive neuromotor development occurs early in human life, and the timing of brain injury may affect the resulting motor impairment. In Part I of this series, it was demonstrated that the distribution of weakness in the upper extremity depended on the timing of brain injury in individuals with childhood-onset hemiparesis. The goal of this study was to characterize how timing of brain injury affects joint torque synergies, or losses of independent joint control. Twenty-four individuals with hemiparesis were divided into 3 groups based on the timing of their injury: before birth (PRE-natal, n = 8), around the time of birth (PERI-natal, n = 8), and after 6 months of age (POST-natal, n = 8). Individuals with hemiparesis and 8 typically developing peers participated in maximal isometric shoulder, elbow, wrist, and finger torque generation tasks while their efforts were recorded by a multiple degree-of-freedom load cell. Motor output in 4 joints of the upper extremity was concurrently measured during 8 primary torque generation tasks to quantify joint torque synergies. There were a number of significant coupling patterns identified in individuals with hemiparesis that differed from the typically developing group. POST-natal differences were most noted in the coupling of shoulder abductors with elbow, wrist, and finger flexors, while the PRE-natal group demonstrated significant distal joint coupling with elbow flexion. The torque synergies measured provide indirect evidence for the use of bulbospinal pathways in the POST-natal group, while those with earlier injury may use relatively preserved ipsilateral corticospinal motor pathways.

  2. Velocity control in three-phase induction motors using PIC; Controle de velocidade de motor de inducao trifasico usando PIC

    Energy Technology Data Exchange (ETDEWEB)

    Marcelino, M.A.; Silva, G.B.S.; Grandinetti, F.J. [Universidade Estadual Paulista (UNESP), Guaratingueta, SP (Brazil). Fac. de Engenharia; Universidade de Taubate (UNITAU), SP (Brazil)], Emails: abud@feg.unesp.br, gabonini@yahoo.com.br, grandinetti@unitau.br

    2009-07-01

    This paper presents a technique for speed control three-phase induction motor using the pulse width modulation (PWM), in open loop while maintaining the tension for constant frequency. The technique is adapted from a thesis entitled 'Control of the three-phase induction motor, using discrete PWM generation, optimized and synchronized', where studies are presented aimed at their application in home appliances, to eliminate mechanical parts, replaced by low cost electronic control, thus having a significant reduction in power consumption. Initially the experiment was done with the Intel 80C31 micro controller. In this paper, the PWM modulation is implemented using a PIC micro controller, and the speed control kept a low profile, based on tables, synchronized with transitions and reduced generation of harmonics in the network. Confirmations were made using the same process of building tables, but takes advantage of the program of a RISC device.

  3. Impulsive control of permanent magnet synchronous motors with parameters uncertainties

    International Nuclear Information System (INIS)

    Li Dong; Zhang Xiaohong; Wang Shilong; Yan Dan; Wang Hui

    2008-01-01

    The permanent magnet synchronous motors (PMSMs) may have chaotic behaviours for the uncertain values of parameters or under certain working conditions, which threatens the secure and stable operation of motor-driven. It is important to study methods of controlling or suppressing chaos in PMSMs. In this paper, robust stabilities of PMSM with parameter uncertainties are investigated. After the uncertain matrices which represent the variable system parameters are formulated through matrix analysis, a novel asymptotical stability criterion is established. Some illustrated examples are also given to show the effectiveness of the obtained results

  4. Sensorless Control of Electric Motors with Kalman Filters: Applications to Robotic and Industrial Systems

    Directory of Open Access Journals (Sweden)

    Gerasimos G. Rigatos

    2011-12-01

    Full Text Available The paper studies sensorless control for DC and induction motors, using Kalman Filtering techniques. First the case of a DC motor is considered and Kalman Filter-based control is implemented. Next the nonlinear model of a field-oriented induction motor is examined and the motor

  5. Fuzzy – PI controller to control the velocity parameter of Induction Motor

    Science.gov (United States)

    Malathy, R.; Balaji, V.

    2018-04-01

    The major application of Induction motor includes the usage of the same in industries because of its high robustness, reliability, low cost, highefficiency and good self-starting capability. Even though it has the above mentioned advantages, it also have some limitations: (1) the standard motor is not a true constant-speed machine, itsfull-load slip varies less than 1 % (in high-horsepower motors).And (2) it is not inherently capable of providing variable-speedoperation. In order to solve the above mentioned problem smart motor controls and variable speed controllers are used. Motor applications involve non linearity features, which can be controlled by Fuzzy logic controller as it is capable of handling those features with high efficiency and it act similar to human operator. This paper presents individuality of the plant modelling. The fuzzy logic controller (FLC)trusts on a set of linguistic if-then rules, a rule-based Mamdani for closed loop Induction Motor model. Themotor model is designed and membership functions are chosenaccording to the parameters of the motor model. Simulation results contains non linearity in induction motor model. A conventional PI controller iscompared practically to fuzzy logic controller using Simulink.

  6. Myoelectric hand prosthesis force control through servo motor current feedback.

    Science.gov (United States)

    Sono, Tálita Saemi Payossim; Menegaldo, Luciano Luporini

    2009-10-01

    This paper presents the prehension force closed-loop control design of a mechanical finger commanded by electromyographic signal (EMG) from a patient's arm. The control scheme was implemented and tested in a mechanical finger prototype with three degrees of freedom and one actuator, driven by arm muscles EMG of normal volunteers. Real-time indirect estimation of prehension force was assessed by measuring the DC servo motor actuator current. A model of the plant comprising finger, motor, and grasped object was proposed. Model parameters were identified experimentally and a classical feedback phase-lead compensator was designed. The controlled mechanical finger was able to provide a more accurate prehension force modulation of a compliant object when compared to open-loop control.

  7. Microgravity induced changes in the control of motor units

    Science.gov (United States)

    de Luca, C.; Roy, S.

    The goal of this project is to understand the effects of microgravity on the control of muscles. It is motivated by the notion that in order to adequately address microgravity-induced deterioration in the force generating capacity of muscles, one needs to understand the changes in the control aspects in addition to histochemical and morphological changes. The investigations into muscle control need to include the regulation of the firing activity of motor units that make up a muscle and the coordination of different muscles responsible for the control of a joint. In order to understand the effects of microgravity on these two aspects of muscle control, we will test astronauts before and after spaceflight. The investigations of the control of motor units will involve intramuscular EMG techniques developed in our laboratory. We will use a quadrifilar electrode to detect simultaneously three differential channels of EMG activity. These data will be decomposed accurately using a sophisticated set of algorithms constructed with artificial intelligence knowledge- based techniques. Particular attention will be paid to the firing rate and recruitment behavior of motor units and we will study the degree of cross-correlation of the firing rates. This approach will enable us to study the firing behavior of several (approx. 10) concurrently active motor units. This analysis will enable us to detect modifications in the control of motor units. We will perform these investigations in a hand muscle, which continues being used in prehensile tasks in space, and a leg muscle whose antigravity role is not needed in space. The comparison of the effects of weightlessness on these muscles will determine if continued use of muscles in space deters the possible deleterious effects of microgravity on the control of motor units, in addition to slowing down atrophy. We are particularly interested in comparing the results of this study to similar data already obtained from elderly subjects

  8. Loss Minimization Sliding Mode Control of IPM Synchronous Motor Drives

    Directory of Open Access Journals (Sweden)

    Mehran Zamanifar

    2010-01-01

    Full Text Available In this paper, a nonlinear loss minimization control strategy for an interior permanent magnet synchronous motor (IPMSM based on a newly developed sliding mode approach is presented. This control method sets force the speed control of the IPMSM drives and simultaneously ensures the minimization of the losses besides the uncertainties exist in the system such as parameter variations which have undesirable effects on the controller performance except at near nominal conditions. Simulation results are presented to show the effectiveness of the proposed controller.

  9. When the brain speaks for itself : exploiting hemodynamic brain signals for motor-independent communication

    NARCIS (Netherlands)

    Sorger, B.

    2010-01-01

    Communication is an essential element of human interaction but can be compromised in several clinical conditions. In the so-called 'locked-in' syndrome (LIS), resulting from a severe motor paralysis, patients are literally confined to their own bodies, while at the same time being fully conscious

  10. A hybrid brain-machine interface based on EEG and EMG activity for the motor rehabilitation of stroke patients.

    Science.gov (United States)

    Sarasola-Sanz, Andrea; Irastorza-Landa, Nerea; Lopez-Larraz, Eduardo; Bibian, Carlos; Helmhold, Florian; Broetz, Doris; Birbaumer, Niels; Ramos-Murguialday, Ander

    2017-07-01

    Including supplementary information from the brain or other body parts in the control of brain-machine interfaces (BMIs) has been recently proposed and investigated. Such enriched interfaces are referred to as hybrid BMIs (hBMIs) and have been proven to be more robust and accurate than regular BMIs for assistive and rehabilitative applications. Electromyographic (EMG) activity is one of the most widely utilized biosignals in hBMIs, as it provides a quite direct measurement of the motion intention of the user. Whereas most of the existing non-invasive EEG-EMG-hBMIs have only been subjected to offline testings or are limited to one degree of freedom (DoF), we present an EEG-EMG-hBMI that allows the simultaneous control of 7-DoFs of the upper limb with a robotic exoskeleton. Moreover, it establishes a biologically-inspired hierarchical control flow, requiring the active participation of central and peripheral structures of the nervous system. Contingent visual and proprioceptive feedback about the user's EEG and EMG activity is provided in the form of velocity modulation during functional task training. We believe that training with this closed-loop system may facilitate functional neuroplastic processes and eventually elicit a joint brain and muscle motor rehabilitation. Its usability is validated during a real-time operation session in a healthy participant and a chronic stroke patient, showing encouraging results for its application to a clinical rehabilitation scenario.

  11. Risks of postoperative paresis in motor eloquently and non-eloquently located brain metastases

    International Nuclear Information System (INIS)

    Obermueller, Thomas; Schaeffner, Michael; Gerhardt, Julia; Meyer, Bernhard; Ringel, Florian; Krieg, Sandro M

    2014-01-01

    When treating cerebral metastases all involved multidisciplinary oncological specialists have to cooperate closely to provide the best care for these patients. For the resection of brain metastasis several studies reported a considerable risk of new postoperative paresis. Pre- and perioperative chemotherapy (Ctx) or radiotherapy (Rtx) alter vasculature and adjacent fiber tracts on the one hand, and many patients already present with paresis prior to surgery on the other hand. As such factors were repeatedly considered risk factors for perioperative complications, we designed this study to also identify risk factors for brain metastases resection. Between 2006 and 2011, we resected 206 brain metastases consecutively, 56 in eloquent motor areas and 150 in non-eloquent ones. We evaluated the influences of preoperative paresis, previous Rtx or Ctx as well as recursive partitioning analysis (RPA) class on postoperative outcome. In general, 8.7% of all patients postoperatively developed a new permanent paresis. In contrast to preoperative Ctx, previous Rtx as a single or combined treatment strategy was a significant risk factor for postoperative motor weakness. This risk was even increased in perirolandic and rolandic lesions. Our data show significantly increased risk of new deficits for patients assigned to RPA class 3. Even in non-eloquently located brain metastases the risk of new postoperative paresis has not to be underestimated. Despite the microsurgical approach, our cohort shows a high rate of unexpected residual tumors in postoperative MRI, which supports recent data on brain metastases’ infiltrative nature but might also be the result of our strict study protocol. Surgical resection is a safe treatment of brain metastases. However, preoperative Rtx and RPA score 3 have to be taken into account when surgical resection is considered

  12. Visual-Motor Control in Baseball Batting

    Directory of Open Access Journals (Sweden)

    Rob Gray

    2011-05-01

    Full Text Available With margins for error of a few milliseconds and fractions of an inch it is not surprising that hitting a baseball is considered to be one of the most difficult acts in all of sports. We have been investigating this challenging behavior using a virtual baseball batting setup in which simulations of an approaching ball, pitcher, and field are combined with real-time recording of bat and limb movements. I will present evidence that baseball batting involves variable pre-programmed control in which the swing direction and movement time (MT are set prior to the initiation of the action but can take different values from swing-to-swing. This programming process utilizes both advance information (pitch history and count and optical information picked-up very early in the ball's flight (ball time to contact TTC and rotation direction. The pre-programmed value of MT is used to determine a critical value of TTC for swing initiation. Finally, because a baseball swing is an action that is occasionally interrupted online (i.e., a “check swing”, I will discuss experiments that examine when this pre-programmed action can be stopped and the sources of optical information that trigger stopping.

  13. Motor and non-motor circuitry activation induced by subthalamic nucleus deep brain stimulation (STN DBS) in Parkinson’s disease patients: Intraoperative fMRI for DBS

    Science.gov (United States)

    Knight, Emily J.; Testini, Paola; Min, Hoon-Ki; Gibson, William S.; Gorny, Krzysztof R.; Favazza, Christopher P.; Felmlee, Joel P.; Kim, Inyong; Welker, Kirk M.; Clayton, Daniel A.; Klassen, Bryan T.; Chang, Su-youne; Lee, Kendall H.

    2015-01-01

    Objective To test the hypothesis suggested by previous studies that subthalamic nucleus (STN) deep brain stimulation (DBS) in patients with PD would affect the activity of both motor and non-motor networks, we applied intraoperative fMRI to patients receiving DBS. Patients and Methods Ten patients receiving STN DBS for PD underwent intraoperative 1.5T fMRI during high frequency stimulation delivered via an external pulse generator. The study was conducted between the dates of January 1, 2013 and September 30, 2014. Results We observed blood oxygen level dependent (BOLD) signal changes (FDR<.001) in the motor circuitry, including primary motor, premotor, and supplementary motor cortices, thalamus, pedunculopontine nucleus (PPN), and cerebellum, as well as in the limbic circuitry, including cingulate and insular cortices. Activation of the motor network was observed also after applying a Bonferroni correction (p<.001) to our dataset, suggesting that, across subjects, BOLD changes in the motor circuitry are more consistent compared to those occurring in the non-motor network. Conclusions These findings support the modulatory role of STN DBS on the activity of motor and non-motor networks, and suggest complex mechanisms at the basis of the efficacy of this treatment modality. Furthermore, these results suggest that, across subjects, BOLD changes in the motor circuitry are more consistent compared to those occurring in the non-motor network. With further studies combining the use of real time intraoperative fMRI with clinical outcomes in patients treated with DBS, functional imaging techniques have the potential not only to elucidate the mechanisms of DBS functioning, but also to guide and assist in the surgical treatment of patients affected by movement and neuropsychiatric disorders. PMID:26046412

  14. Efficiency optimized control of medium-size induction motor drives

    DEFF Research Database (Denmark)

    Abrahamsen, F.; Blaabjerg, Frede; Pedersen, John Kim

    2000-01-01

    The efficiency of a variable speed induction motor drive can be optimized by adaption of the motor flux level to the load torque. In small drives (<10 kW) this can be done without considering the relatively small converter losses, but for medium-size drives (10-1000 kW) the losses can not be disr......The efficiency of a variable speed induction motor drive can be optimized by adaption of the motor flux level to the load torque. In small drives (... not be disregarded without further analysis. The importance of the converter losses on efficiency optimization in medium-size drives is analyzed in this paper. Based on the experiments with a 90 kW drive it is found that it is not critical if the converter losses are neglected in the control, except...... that the robustness towards load disturbances may unnecessarily be reduced. Both displacement power factor and model-based efficiency optimizing control methods perform well in medium-size drives. The last strategy is also tested on a 22 kW drive with good results....

  15. A hybrid NIRS-EEG system for self-paced brain computer interface with online motor imagery.

    Science.gov (United States)

    Koo, Bonkon; Lee, Hwan-Gon; Nam, Yunjun; Kang, Hyohyeong; Koh, Chin Su; Shin, Hyung-Cheul; Choi, Seungjin

    2015-04-15

    For a self-paced motor imagery based brain-computer interface (BCI), the system should be able to recognize the occurrence of a motor imagery, as well as the type of the motor imagery. However, because of the difficulty of detecting the occurrence of a motor imagery, general motor imagery based BCI studies have been focusing on the cued motor imagery paradigm. In this paper, we present a novel hybrid BCI system that uses near infrared spectroscopy (NIRS) and electroencephalography (EEG) systems together to achieve online self-paced motor imagery based BCI. We designed a unique sensor frame that records NIRS and EEG simultaneously for the realization of our system. Based on this hybrid system, we proposed a novel analysis method that detects the occurrence of a motor imagery with the NIRS system, and classifies its type with the EEG system. An online experiment demonstrated that our hybrid system had a true positive rate of about 88%, a false positive rate of 7% with an average response time of 10.36 s. As far as we know, there is no report that explored hemodynamic brain switch for self-paced motor imagery based BCI with hybrid EEG and NIRS system. From our experimental results, our hybrid system showed enough reliability for using in a practical self-paced motor imagery based BCI. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Signal differentiation in position tracking control of dc motors

    International Nuclear Information System (INIS)

    Beltran-Carbajal, F; Valderrabano-Gonzalez, A; Rosas-Caro, J C

    2015-01-01

    An asymptotic differentiation approach with respect to time is used for on-line estimation of velocity and acceleration signals in controlled dc motors. The attractive feature of this differentiator of signals is that it does not require any system mathematical model, which allows its use in engineering systems that require the signal differentiation for its control, identification, fault detection, among other applications. Moreover, it is shown that the differentiation approach can be applied for output signals showing a chaotic behavior. In addition a differential flatness control scheme with additional integral compensation of the output error is proposed for tracking tasks of position reference trajectories for direct current electric motors using angular position measurements only

  17. Fuzzy Impulsive Control of Permanent Magnet Synchronous Motors

    International Nuclear Information System (INIS)

    Dong, Li; Shi-Long, Wang; Xiao-Hong, Zhang; Dan, Yang; Hui, Wang

    2008-01-01

    The permanent magnet synchronous motors (PMSMs) may experience chaotic behaviours with systemic parameters falling into a certain area or under certain working conditions, which threaten the secure and stable operation of motor-driven. Hence, it is important to study the methods of controlling or suppressing chaos in PMSMs. In this work, the Takagi–Sugeno (T-S) fuzzy impulsive control model for PMSMs is established via the T-S modelling methodology and impulsive technology. Based on the new model, the control conditions of asymptotical stability and exponential stability for PMSMs have been derived by the Lyapunov method. Finally, an illustrated example is also given to show the effectiveness of the obtained results

  18. Novel intelligent PID control of traveling wave ultrasonic motor.

    Science.gov (United States)

    Jingzhuo, Shi; Yu, Liu; Jingtao, Huang; Meiyu, Xu; Juwei, Zhang; Lei, Zhang

    2014-09-01

    A simple control strategy with acceptable control performance can be a good choice for the mass production of ultrasonic motor control system. In this paper, through the theoretic and experimental analyses of typical control process, a simpler intelligent PID speed control strategy of TWUM is proposed, involving only two expert rules to adjust the PID control parameters based on the current status. Compared with the traditional PID controller, this design requires less calculation and more cheap chips which can be easily involved in online performance. Experiments with different load torques and voltage amplitudes show that the proposed controller can deal with the nonlinearity and load disturbance to maintain good control performance of TWUM. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  19. MaLT - Combined Motor and Language Therapy Tool for Brain Injury Patients Using Kinect.

    Science.gov (United States)

    Wairagkar, Maitreyee; McCrindle, Rachel; Robson, Holly; Meteyard, Lotte; Sperrin, Malcom; Smith, Andy; Pugh, Moyra

    2017-03-23

    The functional connectivity and structural proximity of elements of the language and motor systems result in frequent co-morbidity post brain injury. Although rehabilitation services are becoming increasingly multidisciplinary and "integrated", treatment for language and motor functions often occurs in isolation. Thus, behavioural therapies which promote neural reorganisation do not reflect the high intersystem connectivity of the neurologically intact brain. As such, there is a pressing need for rehabilitation tools which better reflect and target the impaired cognitive networks. The objective of this research is to develop a combined high dosage therapy tool for language and motor rehabilitation. The rehabilitation therapy tool developed, MaLT (Motor and Language Therapy), comprises a suite of computer games targeting both language and motor therapy that use the Kinect sensor as an interaction device. The games developed are intended for use in the home environment over prolonged periods of time. In order to track patients' engagement with the games and their rehabilitation progress, the game records patient performance data for the therapist to interrogate. MaLT incorporates Kinect-based games, a database of objects and language parameters, and a reporting tool for therapists. Games have been developed that target four major language therapy tasks involving single word comprehension, initial phoneme identification, rhyme identification and a naming task. These tasks have 8 levels each increasing in difficulty. A database of 750 objects is used to programmatically generate appropriate questions for the game, providing both targeted therapy and unique gameplay every time. The design of the games has been informed by therapists and by discussions with a Public Patient Involvement (PPI) group. Pilot MaLT trials have been conducted with three stroke survivors for the duration of 6 to 8 weeks. Patients' performance is monitored through MaLT's reporting facility

  20. Controlling Precision Stepper Motors in Flight Using (Almost) No Parts

    Science.gov (United States)

    Randall, David

    2010-01-01

    This concept allows control of high-performance stepper motors with minimal parts count and minimal flight software complexity. Although it uses a small number of common flight-qualified parts and simple control algorithms, it is capable enough to meet demanding system requirements. Its programmable nature makes it trivial to implement changes to control algorithms both during integration & test and in flight. Enhancements such as microstepping, half stepping, back-emf compensation, and jitter reduction can be tailored to the requirements of a large variety of stepper motor based applications including filter wheels, focus mechanisms, antenna tracking subsystems, pointing and mobility. The hardware design (using an H-bridge motor controller IC) was adapted from JPL's MER mission, still operating on Mars. This concept has been fully developed and incorporated into the MCS instrument on MRO, currently operating in Mars orbit. It has been incorporated into the filter wheel mechanism and linear stage (focus) mechanism for the AMT instrument. On MCS/MRO, two of these circuits control the elevation and azimuth of the MCS telescope/radiometer assembly, allowing the instrument to continuously monitor the limb of the Martian atmosphere. Implementation on MCS/MRO resulted in a 4:1 reduction in the volume and mass required for the motor driver electronics (100:25 square inches of PCB space), producing a very compact instrument. In fact, all of the electronics for the MCS instrument are packaged within the movable instrument structure. It also saved approximately 3 Watts of power. Most importantly, the design enabled MCS to meet very its stringent maximum allowable torque disturbance requirements.

  1. Electromagnetic phenomena analysis in brushless DC motor with speed control using PWM method

    Science.gov (United States)

    Ciurys, Marek Pawel

    2017-12-01

    Field-circuit model of a brushless DC motor with speed control using PWM method was developed. Waveforms of electrical and mechanical quantities of the designed motor with a high pressure vane pump built in a rotor of the motor were computed. Analysis of electromagnetic phenomena in the system: single phase AC network - converter - BLDC motor was carried out.

  2. Repeated sessions of noninvasive brain DC stimulation is associated with motor function improvement in stroke patients.

    Science.gov (United States)

    Boggio, Paulo S; Nunes, Alice; Rigonatti, Sergio P; Nitsche, Michael A; Pascual-Leone, Alvaro; Fregni, Felipe

    2007-01-01

    Recent evidence has suggested that a simple technique of noninvasive brain stimulation - transcranial direct current stimulation (tDCS) - is associated with a significant motor function improvement in stroke patients. We tested the motor performance improvement in stroke patients following 4 weekly sessions of sham, anodal- and cathodal tDCS (experiment 1) and the effects of 5 consecutive daily sessions of cathodal tDCS (experiment 2). A blinded rater evaluated motor function using the Jebsen-Taylor Hand Function Test. There was a significant main effect of stimulation condition (p=0.009) in experiment 1. Furthermore there was a significant motor function improvement after either cathodal tDCS of the unaffected hemisphere (p=0.016) or anodal tDCS of the affected hemisphere (p=0.046) when compared to sham tDCS. There was no cumulative effect associated with weekly sessions of tDCS, however consecutive daily sessions of tDCS (experiment 2) were associated with a significant effect on time (pmotor function improvement in stroke patients; and support that consecutive daily sessions of tDCS might increase its behavioral effects. Because the technique of tDCS is simple, safe and non-expensive; our findings support further research on the use of this technique for the rehabilitation of patients with stroke.

  3. Low speed phaselock speed control system. [for brushless dc motor

    Science.gov (United States)

    Fulcher, R. W.; Sudey, J. (Inventor)

    1975-01-01

    A motor speed control system for an electronically commutated brushless dc motor is provided which includes a phaselock loop with bidirectional torque control for locking the frequency output of a high density encoder, responsive to actual speed conditions, to a reference frequency signal, corresponding to the desired speed. The system includes a phase comparator, which produces an output in accordance with the difference in phase between the reference and encoder frequency signals, and an integrator-digital-to-analog converter unit, which converts the comparator output into an analog error signal voltage. Compensation circuitry, including a biasing means, is provided to convert the analog error signal voltage to a bidirectional error signal voltage which is utilized by an absolute value amplifier, rotational decoder, power amplifier-commutators, and an arrangement of commutation circuitry.

  4. Self-Controlled Feedback for a Complex Motor Task

    Directory of Open Access Journals (Sweden)

    Wolf Peter

    2011-12-01

    Full Text Available Self-controlled augmented feedback enhances learning of simple motor tasks. Thereby, learners tend to request feedback after trials that were rated as good by themselves. Feedback after good trials promotes positive reinforcement, which enhances motor learning. The goal of this study was to investigate when naïve learners request terminal visual feedback in a complex motor task, as conclusions drawn on simple tasks can hardly be transferred to complex tasks. Indeed, seven of nine learners stated to have intended to request feedback predominantly after good trials, but in contrast to their intention, kinematic analysis showed that feedback was rather requested randomly (23% after good, 44% after intermediate, 33% after bad trials. Moreover, requesting feedback after good trials did not correlate with learning success. It seems that self-estimation of performance in complex tasks is challenging. As a consequence, learners might have focused on certain movement aspects rather than on the overall movement. Further studies should assess the current focus of the learner in detail to gain more insight in self-estimation capabilities during complex motor task learning.

  5. Role of brain hemispheric dominance in anticipatory postural control strategies.

    Science.gov (United States)

    Cioncoloni, David; Rosignoli, Deborah; Feurra, Matteo; Rossi, Simone; Bonifazi, Marco; Rossi, Alessandro; Mazzocchio, Riccardo

    2016-07-01

    Most of the cerebral functions are asymmetrically represented in the two hemispheres. Moreover, dexterity and coordination of the distal segment of the dominant limbs depend on cortico-motor lateralization. In this study, we investigated whether postural control may be also considered a lateralized hemispheric brain function. To this aim, 15 young subjects were tested in standing position by measuring center of pressure (COP) shifts along the anteroposterior axis (COP-Y) during dynamic posturography before and after continuous Theta Burst Stimulation (cTBS) intervention applied to the dominant or non-dominant M1 hand area as well as to the vertex. We show that when subjects were expecting a forward platform translation, the COP-Y was positioned significantly backward or forward after dominant or non-dominant M1 stimulation, respectively. We postulate that cTBS applied on M1 may have disrupted the functional connectivity between intra- and interhemispheric areas implicated in the anticipatory control of postural stability. This study suggests a functional asymmetry between the two homologous primary motor areas, with the dominant hemisphere playing a critical role in the selection of the appropriate postural control strategy.

  6. Motor programme activating therapy influences adaptive brain functions in multiple sclerosis: clinical and MRI study.

    Science.gov (United States)

    Rasova, Kamila; Prochazkova, Marie; Tintera, Jaroslav; Ibrahim, Ibrahim; Zimova, Denisa; Stetkarova, Ivana

    2015-03-01

    There is still little scientific evidence for the efficacy of neurofacilitation approaches and their possible influence on brain plasticity and adaptability. In this study, the outcome of a new kind of neurofacilitation approach, motor programme activating therapy (MPAT), was evaluated on the basis of a set of clinical functions and with MRI. Eighteen patients were examined four times with standardized clinical tests and diffusion tensor imaging to monitor changes without therapy, immediately after therapy and 1 month after therapy. Moreover, the strength of effective connectivity was analysed before and after therapy. Patients underwent a 1-h session of MPAT twice a week for 2 months. The data were analysed by nonparametric tests of association and were subsequently statistically evaluated. The therapy led to significant improvement in clinical functions, significant increment of fractional anisotropy and significant decrement of mean diffusivity, and decrement of effective connectivity at supplementary motor areas was observed immediately after the therapy. Changes in clinical functions and diffusion tensor images persisted 1 month after completing the programme. No statistically significant changes in clinical functions and no differences in MRI-diffusion tensor images were observed without physiotherapy. Positive immediate and long-term effects of MPAT on clinical and brain functions, as well as brain microstructure, were confirmed.

  7. When syntax meets action: Brain potential evidence of overlapping between language and motor sequencing.

    Science.gov (United States)

    Casado, Pilar; Martín-Loeches, Manuel; León, Inmaculada; Hernández-Gutiérrez, David; Espuny, Javier; Muñoz, Francisco; Jiménez-Ortega, Laura; Fondevila, Sabela; de Vega, Manuel

    2018-03-01

    This study aims to extend the embodied cognition approach to syntactic processing. The hypothesis is that the brain resources to plan and perform motor sequences are also involved in syntactic processing. To test this hypothesis, Event-Related brain Potentials (ERPs) were recorded while participants read sentences with embedded relative clauses, judging for their acceptability (half of the sentences contained a subject-verb morphosyntactic disagreement). The sentences, previously divided into three segments, were self-administered segment-by-segment in two different sequential manners: linear or non-linear. Linear self-administration consisted of successively pressing three buttons with three consecutive fingers in the right hand, while non-linear self-administration implied the substitution of the finger in the middle position by the right foot. Our aim was to test whether syntactic processing could be affected by the manner the sentences were self-administered. Main results revealed that the ERPs LAN component vanished whereas the P600 component increased in response to incorrect verbs, for non-linear relative to linear self-administration. The LAN and P600 components reflect early and late syntactic processing, respectively. Our results convey evidence that language syntactic processing and performing non-linguistic motor sequences may share resources in the human brain. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Motor rehabilitation after traumatic brain injury and stroke - Advances in assessment and therapy.

    Science.gov (United States)

    Platz, Thomas; Hesse, S.; Mauritz, K.-H.

    1999-01-01

    A long-term goal in motor rehabilitation is that treatment is not selected on the basis of 'schools of thought', but rather, based on knowledge about efficacy and effectiveness of specific interventions for specific situations (e.g. functional syndromes). Motor dysfunction after stroke or TBI can be caused by many different functional syndromes such as paresis, ataxia, deafferentaion, visuo-perceptual deficits, or apraxia. Examples are provided showing that theory-based analysis of motor behavior makes it possible to describe 'syndrome-specific motor deficits'. Its potential implications for motor rehabilitation are that our understanding of altered motor behavior as well as specific therapeutic approaches might be promoted. A methodological prerequisite for clinical trials in rehabilitation is knowledge about test properties of assessment tools in follow-up situations such as test-retest reliability and responsiveness to change. Test-retest reliability assesses whether a test can produce stable measures with test repetition, while sensitivity to change reflects whether a test detects changes that occur over time. Exemplifying these considerations, a reliability and validity study of a kinematic arm movement analysis is summarized. In terms of new therapeutic developments, two examples of clinical therapeutic studies are provided assessing the efficacy of specific inter-ventions for specific situations in arm and gait rehabilitation: the Arm Ability Training for high functioning hemiparetic stroke and TBI patients, and the treadmill training for non-ambulatory hemiparetic patients. In addition, a new technical development, a machine-controlled gait trainer ist introduced.

  9. Vector Control Algorithm for Electric Vehicle AC Induction Motor Based on Improved Variable Gain PID Controller

    Directory of Open Access Journals (Sweden)

    Gang Qin

    2015-01-01

    Full Text Available The acceleration performance of EV, which affects a lot of performances of EV such as start-up, overtaking, driving safety, and ride comfort, has become increasingly popular in recent researches. An improved variable gain PID control algorithm to improve the acceleration performance is proposed in this paper. The results of simulation with Matlab/Simulink demonstrate the effectiveness of the proposed algorithm through the control performance of motor velocity, motor torque, and three-phase current of motor. Moreover, it is investigated that the proposed controller is valid by comparison with the other PID controllers. Furthermore, the AC induction motor experiment set is constructed to verify the effect of proposed controller.

  10. Neuromodulation of lower limb motor control in restorative neurology

    OpenAIRE

    Minassian, Karen; Hofstoetter, Ursula; Tansey, Keith; Mayr, Winfried

    2012-01-01

    One consequence of central nervous system injury or disease is the impairment of neural control of movement, resulting in spasticity and paralysis. To enhance recovery, restorative neurology procedures modify altered, yet preserved nervous system function. This review focuses on functional electrical stimulation (FES) and spinal cord stimulation (SCS) that utilize remaining capabilities of the distal apparatus of spinal cord, peripheral nerves and muscles in upper motor neuron dysfunctions. F...

  11. SPEED CONTROL OF DC MOTOR ON LOAD USING FUZZY LOGIC ...

    African Journals Online (AJOL)

    This paper presents the development of a fuzzy logic controller for the driver DC motor in the lube oil system of the H25 Hitachi gas turbine generator. The turbine generator is required to run at an operating pressure of 1.5bar with the low and the high pressure trip points being 0.78 bar and 1.9 bar respectively. However, the ...

  12. Perceived effort for motor control and decision-making.

    Directory of Open Access Journals (Sweden)

    Ignasi Cos

    2017-08-01

    Full Text Available How effort is internally quantified and how it influences both movement generation and decisions between potential movements are 2 difficult questions to answer. Physical costs are known to influence motor control and decision-making, yet we lack a general, principled characterization of how the perception of effort operates across tasks and conditions. Morel and colleagues introduce an insightful approach to that end, assessing effort indifference points and presenting a quadratic law between perceived effort and force production.

  13. Voluntary inhibitory motor control over involuntary tic movements.

    Science.gov (United States)

    Ganos, Christos; Rothwell, John; Haggard, Patrick

    2018-03-06

    Inhibitory control is crucial for normal adaptive motor behavior. In hyperkinesias, such as tics, disinhibition within the cortico-striato-thalamo-cortical loops is thought to underlie the presence of involuntary movements. Paradoxically, tics are also subject to voluntary inhibitory control. This puzzling clinical observation questions the traditional definition of tics as purely involuntary motor behaviors. Importantly, it suggests novel insights into tic pathophysiology. In this review, we first define voluntary inhibitory tic control and compare it with other notions of tic control from the literature. We then examine the association between voluntary inhibitory tic control with premonitory urges and review evidence linking voluntary tic inhibition to other forms of executive control of action. We discuss the somatotopic selectivity and the neural correlates of voluntary inhibitory tic control. Finally, we provide a scientific framework with regard to the clinical relevance of the study of voluntary inhibitory tic control within the context of the neurodevelopmental disorder of Tourette syndrome. We identify current knowledge gaps that deserve attention in future research. © 2018 International Parkinson and Movement Disorder Society. © 2018 International Parkinson and Movement Disorder Society.

  14. Verification of control system using inverter and canned motor pump

    International Nuclear Information System (INIS)

    Sawada, Yoshiaki; Misato, Hisashi

    2002-01-01

    Control on flow volume and so on of auxiliary systems at power stations is generally carried out by using control valves (CVs), of which numbers and kinds ranges to wide areas. CVs are required for periodical change of packing and so on, of which labor for maintenance is never few. Therefore, to reduce the maintenance of CVs, a system to operate pumps by using an inverter control was investigated. When carrying out flow control by an inverter, valves at output side of pumps was made perfectly open, but because of control on rotation numbers so as to keep required amount excess energy is never consumed. And, by reducing flow volume of a pump, consumed energy is reduced at a rate of its three powers as feature of pumps, so large energy saving effect can be established. Selected canned motor pumps have such characteristics as upgrading of reliability for leakage because of their seal-less ones and extension of periodical inspection period by setting a monitor for abrasion of bearings. As results of some investigations, it could be considered that a control system combining an inverter with a canned motor pump had equal feature as that of a control system using CVs. And, from a test result adding useless time and first order delay element to its control feature forecasting on its application to practical machine could be obtained. (G.K.)

  15. The influence of scopolamine on motor control and attentional processes

    Directory of Open Access Journals (Sweden)

    Emma Bestaven

    2016-05-01

    Full Text Available Background: Motion sickness may be caused by a sensory conflict between the visual and the vestibular systems. Scopolamine, known to be the most effective therapy to control the vegetative symptoms of motion sickness, acts on the vestibular nucleus and potentially the vestibulospinal pathway, which may affect balance and motor tasks requiring both attentional process and motor balance. The aim of this study was to explore the effect of scopolamine on motor control and attentional processes. Methods: Seven subjects were evaluated on four different tasks before and after a subcutaneous injection of scopolamine (0.2 mg: a one-minute balance test, a subjective visual vertical test, a pointing task and a galvanic vestibular stimulation with EMG recordings. Results: The results showed that the reaction time and the movement duration were not modified after the injection of scopolamine. However, there was an increase in the center of pressure displacement during the balance test, a decrease in EMG muscle response after galvanic vestibular stimulation and an alteration in the perception of verticality. Discussion: These results confirm that low doses of scopolamine such as those prescribed to avoid motion sickness have no effect on attentional processes, but that it is essential to consider the responsiveness of each subject. However, scopolamine did affect postural control and the perception of verticality. In conclusion, the use of scopolamine to prevent motion sickness must be considered carefully because it could increase imbalances in situations when individuals are already at risk of falling (e.g., sailing, parabolic flight.

  16. Piano training in youths with hand motor impairments after damage to the developing brain

    Directory of Open Access Journals (Sweden)

    Lampe R

    2015-08-01

    Full Text Available Renée Lampe,1,* Anna Thienel,2 Jürgen Mitternacht,1 Tobias Blumenstein,1 Varvara Turova,1 Ana Alves-Pinto1,* 1Research Unit for Paediatric Neuroorthopaedics and Cerebral Palsy, Orthopaedics Department, Klinikum Rechts der Isar, Technische Universität München, 2Department Sonderpädagogik, Ludwig Maximilians-Universität München, Munich, Germany *These authors contributed equally to this work Abstract: Damage to the developing brain may lead to impairment of the hand motor function and negatively impact on patients’ quality of life. Development of manual dexterity and finger and hand motor function may be promoted by learning to play the piano. The latter brings together music with the intensive training of hand coordination and fine finger mobility. We investigated if learning to play the piano helped to improve hand motor skills in 18 youths with hand motor disorders resulting from damage during early brain development. Participants trained 35–40 minutes twice a week for 18 months with a professional piano teacher. With the use of a Musical Instrument Digital Interface piano, the uniformity of finger strokes could be objectively assessed from the timing of keystrokes. The analysis showed a significant improvement in the uniformity of keystrokes during the training. Furthermore, the youths showed strong motivation and engagement during the study. This is nevertheless an open study, and further studies remain needed to exclude effects of growth and concomitant therapies on the improvements observed and clarify which patients will more likely benefit from learning to play the piano. Keywords: manual skill, cerebral palsy, neurodevelopmental disorder, music, rehabilitation

  17. Posterolateral Trajectories Favor a Longer Motor Domain in Subthalamic Nucleus Deep Brain Stimulation for Parkinson Disease.

    Science.gov (United States)

    Tamir, Idit; Marmor-Levin, Odeya; Eitan, Renana; Bergman, Hagai; Israel, Zvi

    2017-10-01

    The clinical outcome of patients with Parkinson disease (PD) who undergo subthalamic nucleus (STN) deep brain stimulation (DBS) is, in part, determined by the length of the electrode trajectory through the motor STN domain, the dorsolateral oscillatory region (DLOR). Trajectory length has been found to correlate with the stimulation-related improvement in patients' motor function (estimated by part III of the United Parkinson's Disease Rating Scale [UPDRS]). Therefore, it seems that ideally trajectories should have maximal DLOR length. We retrospectively studied the influence of various anatomic aspects of the brains of patients with PD and the geometry of trajectories planned on the length of the DLOR and STN recorded during DBS surgery. We examined 212 trajectories and 424 microelectrode recording tracks in 115 patients operated on in our center between 2010 and 2015. We found a strong correlation between the length of the recorded DLOR and STN. Trajectories that were more lateral and/or posterior in orientation had a longer STN and DLOR pass, although the DLOR/STN fraction length remained constant. The STN target was more lateral when the third ventricle was wider, and the latter correlated with older age and male gender. Trajectory angles correlate with the recorded STN and DLOR lengths, and should be altered toward a more posterolateral angle in older patients and atrophied brains to compensate for the changes in STN location and geometry. These fine adjustments should yield a longer motor domain pass, thereby improving the patient's predicted outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Prefrontal control of cerebellum-dependent associative motor learning.

    Science.gov (United States)

    Chen, Hao; Yang, Li; Xu, Yan; Wu, Guang-yan; Yao, Juan; Zhang, Jun; Zhu, Zhi-ru; Hu, Zhi-an; Sui, Jian-feng; Hu, Bo

    2014-02-01

    Behavioral studies have demonstrated that both medial prefrontal cortex (mPFC) and cerebellum play critical roles in trace eyeblink conditioning. However, little is known regarding the mechanism by which the two brain regions interact. By use of electrical stimulation of the caudal mPFC as a conditioned stimulus, we show evidence that persistent outputs from the mPFC to cerebellum are necessary and sufficient for the acquisition and expression of a trace conditioned response (CR)-like response. Specifically, the persistent outputs of caudal mPFC are relayed to the cerebellum via the rostral part of lateral pontine nuclei. Moreover, interfering with persistent activity by blockade of the muscarinic Ach receptor in the caudal mPFC impairs the expression of learned trace CRs. These results suggest an important way for the caudal mPFC to interact with the cerebellum during associative motor learning.

  19. Towards building hybrid biological/in silico neural networks for motor neuroprosthetic control

    Directory of Open Access Journals (Sweden)

    Mehmet eKocaturk

    2015-08-01

    Full Text Available In this article, we introduce the Bioinspired Neuroprosthetic Design Environment (BNDE as a practical platform for the development of novel brain machine interface (BMI controllers which are based on spiking model neurons. We built the BNDE around a hard real-time system so that it is capable of creating simulated synapses from extracellularly recorded neurons to model neurons. In order to evaluate the practicality of the BNDE for neuroprosthetic control experiments, a novel, adaptive BMI controller was developed and tested using real-time closed-loop simulations. The present controller consists of two in silico medium spiny neurons which receive simulated synaptic inputs from recorded motor cortical neurons. In the closed-loop simulations, the recordings from the cortical neurons were imitated using an external, hardware-based neural signal synthesizer. By implementing a reward-modulated spike timing-dependent plasticity rule, the controller achieved perfect target reach accuracy for a two target reaching task in one dimensional space. The BNDE combines the flexibility of software-based spiking neural network (SNN simulations with powerful online data visualization tools and is a low-cost, PC-based and all-in-one solution for developing neurally-inspired BMI controllers. We believe the BNDE is the first implementation which is capable of creating hybrid biological/in silico neural networks for motor neuroprosthetic control and utilizes multiple CPU cores for computationally intensive real-time SNN simulations.

  20. Balance Training Reduces Brain Activity during Motor Simulation of a Challenging Balance Task in Older Adults: An fMRI Study.

    Science.gov (United States)

    Ruffieux, Jan; Mouthon, Audrey; Keller, Martin; Mouthon, Michaël; Annoni, Jean-Marie; Taube, Wolfgang

    2018-01-01

    Aging is associated with a shift from an automatic to a more cortical postural control strategy, which goes along with deteriorations in postural stability. Although balance training has been shown to effectively counteract these behavioral deteriorations, little is known about the effect of balance training on brain activity during postural tasks in older adults. We, therefore, assessed postural stability and brain activity using fMRI during motor imagery alone (MI) and in combination with action observation (AO; i.e., AO+MI) of a challenging balance task in older adults before and after 5 weeks of balance training. Results showed a nonsignificant trend toward improvements in postural stability after balance training, accompanied by reductions in brain activity during AO+MI of the balance task in areas relevant for postural control, which have been shown to be over-activated in older adults during (simulation of) motor performance, including motor, premotor, and multisensory vestibular areas. This suggests that balance training may reverse the age-related cortical over-activations and lead to changes in the control of upright posture toward the one observed in young adults.

  1. Brain implants for substituting lost motor function: state of the art and potential impact on the lives of motor-impaired seniors.

    Science.gov (United States)

    Ramsey, N F; Aarnoutse, E J; Vansteensel, M J

    2014-01-01

    Recent scientific achievements bring the concept of neural prosthetics for reinstating lost motor function closer to medical application. Current research involves severely paralyzed people under the age of 65, but implications for seniors with stroke or trauma-induced impairments are clearly on the horizon. Demographic changes will lead to a shortage of personnel to care for an increasing population of senior citizens, threatening maintenance of an acceptable level of care and urging ways for people to live longer at their home independent from personal assistance. This is particularly challenging when people suffer from disabilities such as partial paralysis after stroke or trauma, where daily personal assistance is required. For some of these people, neural prosthetics can reinstate some lost motor function and/or lost communication, thereby increasing independence and possibly quality of life. In this viewpoint article, we present the state of the art in decoding brain activity in the service of brain-computer interfacing. Although some noninvasive applications produce good results, we focus on brain implants that benefit from better quality brain signals. Fully implantable neural prostheses for home use are not available yet, but clinical trials are being prepared. More sophisticated systems are expected to follow in the years to come, with capabilities of interest for less severe paralysis. Eventually the combination of smart robotics and brain implants is expected to enable people to interact well enough with their environment to live an independent life in spite of motor disabilities. © 2014 S. Karger AG, Basel.

  2. Dual capacity compressor with reversible motor and controls arrangement therefor

    Science.gov (United States)

    Sisk, Francis J.

    1980-12-02

    A hermetic reciprocating compressor such as may be used in heat pump applications is provided for dual capacity operation by providing the crankpin of the crankshaft with an eccentric ring rotatably mounted thereon, and with the end of the connecting rod opposite the piston encompassing the outer circumference of the eccentric ring, with means limiting the rotation of the eccentric ring upon the crankpin between one end point and an opposite angularly displaced end point to provide different values of eccentricity depending upon which end point the eccentric ring is rotated to upon the crankpin, and a reversible motor in the hermetic shell of the compressor for rotating the crankshaft, the motor operating in one direction effecting the angular displacement of the eccentric ring relative to the crankpin to the one end point, and in the opposite direction effecting the angular displacement of the eccentric ring relative to the crankpin to the opposite end point, this arrangement automatically giving different stroke lengths depending upon the direction of motor rotation. The mechanical structure of the arrangement may take various forms including at least one in which any impact of reversal is reduced by utilizing lubricant passages and chambers at the interface area of the crankpin and eccentric ring to provide a dashpot effect. In the main intended application of the arrangement according to the invention, that is, in a refrigerating or air conditioning system, it is desirable to insure a delay during reversal of the direction of compressor operation. A control arrangement is provided in which the control system controls the direction of motor operation in accordance with temperature conditions, the system including control means for effecting operation in a low capacity direction or alternatively in a high capacity direction in response to one set, and another set, respectively, of temperature conditions and with timer means delaying a restart of the compressor

  3. Direct Torque Control With Feedback Linearization for Induction Motor Drives

    DEFF Research Database (Denmark)

    Lascu, Cristian; Jafarzadeh, Saeed; Fadali, Sami M.

    2017-01-01

    This paper describes a direct-torque-controlled (DTC) induction motor (IM) drive that employs feedback linearization and sliding-mode control (SMC). A new feedback linearization approach is proposed, which yields a decoupled linear IM model with two state variables: torque and stator flux magnitude....... This intuitive linear model is used to implement a DTC-type controller that preserves all DTC advantages and eliminates its main drawback, the flux and torque ripple. Robust, fast, and ripple-free control is achieved by using SMC with proportional control in the vicinity of the sliding surface. SMC assures...... in simulations. The sliding controller is compared with a linear DTC scheme with and without feedback linearization. Extensive experimental results for a sensorless IM drive validate the proposed solution....

  4. Universal adaptive torque control for PM motors for field-weakening region operation

    Science.gov (United States)

    Royak, Semyon [Beachwood, OH; Harbaugh, Mark M [Richfield, OH; Breitzmann, Robert J [South Russel, OH; Nondahl, Thomas A [Wauwatosa, WI; Schmidt, Peter B [Franklin, WI; Liu, Jingbo [Milwaukee, WI

    2011-03-29

    The invention includes a motor controller and method for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by, among other things, receiving a torque command, determining a normalized torque command by normalizing the torque command to a characteristic current of the motor, determining a normalized maximum available voltage, determining an inductance ratio of the motor, and determining a direct-axis current based upon the normalized torque command, the normalized maximum available voltage, and the inductance ratio of the motor.

  5. Implementation of FPGA based PID Controller for DC Motor Speed Control System

    Directory of Open Access Journals (Sweden)

    Savita SONOLI

    2010-03-01

    Full Text Available In this paper, the implementation of software module using ‘VHDL’ for Xilinx FPGA (XC3S400 based PID controller for DC motor speed control system is presented. The tools used for building and testing the software modules are Xilinx ISE 9.2i and ModelSim XE III 6.3c. Before verifying the design on FPGA the complete design is simulated using Modelsim Simulation tool. A test bench is written where the set speed can be changed for the motor. It is observed that the motor speed gradually changes to the set speed and locks to the set speed.

  6. The brain decade in debate: VI. Sensory and motor maps: dynamics and plasticity

    Directory of Open Access Journals (Sweden)

    A. Das

    2001-12-01

    Full Text Available This article is an edited transcription of a virtual symposium promoted by the Brazilian Society of Neuroscience and Behavior (SBNeC. Although the dynamics of sensory and motor representations have been one of the most studied features of the central nervous system, the actual mechanisms of brain plasticity that underlie the dynamic nature of sensory and motor maps are not entirely unraveled. Our discussion began with the notion that the processing of sensory information depends on many different cortical areas. Some of them are arranged topographically and others have non-topographic (analytical properties. Besides a sensory component, every cortical area has an efferent output that can be mapped and can influence motor behavior. Although new behaviors might be related to modifications of the sensory or motor representations in a given cortical area, they can also be the result of the acquired ability to make new associations between specific sensory cues and certain movements, a type of learning known as conditioning motor learning. Many types of learning are directly related to the emotional or cognitive context in which a new behavior is acquired. This has been demonstrated by paradigms in which the receptive field properties of cortical neurons are modified when an animal is engaged in a given discrimination task or when a triggering feature is paired with an aversive stimulus. The role of the cholinergic input from the nucleus basalis to the neocortex was also highlighted as one important component of the circuits responsible for the context-dependent changes that can be induced in cortical maps.

  7. Pain and motor control: From the laboratory to rehabilitation.

    Science.gov (United States)

    Hodges, Paul W

    2011-04-01

    Movement is changed in pain and is the target of clinical interventions. Yet the understanding of the physiological basis for movement adaptation in pain remains limited. Contemporary theories are relatively simplistic and fall short of providing an explanation for the variety of permutations of changes in movement control identified in clinical and experimental contexts. The link between current theories and rehabilitation is weak at best. New theories are required that both account for the breadth of changes in motor control in pain and provide direction for development and refinement of clinical interventions. This paper describes an expanded theory of the motor adaptation to pain to address these two issues. The new theory, based on clinical and experimental data argues that: activity is redistributed within and between muscles rather than stereotypical inhibition or excitation of muscles; modifies the mechanical behaviour in a variable manner with the objective to "protect" the tissues from further pain or injury, or threatened pain or injury; involves changes at multiple levels of the motor system that may be complementary, additive or competitive; and has short-term benefit, but with potential long-term consequences due to factors such as increased load, decreased movement, and decreased variability. This expanded theory provides guidance for rehabilitation directed at alleviating a mechanical contribution to the recurrence and persistence of pain that must be balanced with other aspects of a multifaceted intervention that includes management of psychosocial aspects of the pain experience. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Motor Control Training for the Shoulder with Smart Garments.

    Science.gov (United States)

    Wang, Qi; De Baets, Liesbet; Timmermans, Annick; Chen, Wei; Giacolini, Luca; Matheve, Thomas; Markopoulos, Panos

    2017-07-22

    Wearable technologies for posture monitoring and posture correction are emerging as a way to support and enhance physical therapy treatment, e.g., for motor control training in neurological disorders or for treating musculoskeletal disorders, such as shoulder, neck, or lower back pain. Among the various technological options for posture monitoring, wearable systems offer potential advantages regarding mobility, use in different contexts and sustained tracking in daily life. We describe the design of a smart garment named Zishi to monitor compensatory movements and evaluate its applicability for shoulder motor control training in a clinical setting. Five physiotherapists and eight patients with musculoskeletal shoulder pain participated in the study. The attitudes of patients and therapists towards the system were measured using standardized survey instruments. The results indicate that patients and their therapists consider Zishi a credible aid for rehabilitation and patients expect it will help towards their recovery. The system was perceived as highly usable and patients were motivated to train with the system. Future research efforts on the improvement of the customization of feedback location and modality, and on the evaluation of Zishi as support for motor learning in shoulder patients, should be made.

  9. Neuromodulation of lower limb motor control in restorative neurology.

    Science.gov (United States)

    Minassian, Karen; Hofstoetter, Ursula; Tansey, Keith; Mayr, Winfried

    2012-06-01

    One consequence of central nervous system injury or disease is the impairment of neural control of movement, resulting in spasticity and paralysis. To enhance recovery, restorative neurology procedures modify altered, yet preserved nervous system function. This review focuses on functional electrical stimulation (FES) and spinal cord stimulation (SCS) that utilize remaining capabilities of the distal apparatus of spinal cord, peripheral nerves and muscles in upper motor neuron dysfunctions. FES for the immediate generation of lower limb movement along with current rehabilitative techniques is reviewed. The potential of SCS for controlling spinal spasticity and enhancing lower limb function in multiple sclerosis and spinal cord injury is discussed. The necessity for precise electrode placement and appropriate stimulation parameter settings to achieve therapeutic specificity is elaborated. This will lead to our human work of epidural and transcutaneous stimulation targeting the lumbar spinal cord for enhancing motor functions in spinal cord injured people, supplemented by pertinent human research of other investigators. We conclude that the concept of restorative neurology recently received new appreciation by accumulated evidence for locomotor circuits residing in the human spinal cord. Technological and clinical advancements need to follow for a major impact on the functional recovery in individuals with severe damage to their motor system. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Neural and Fuzzy Adaptive Control of Induction Motor Drives

    International Nuclear Information System (INIS)

    Bensalem, Y.; Sbita, L.; Abdelkrim, M. N.

    2008-01-01

    This paper proposes an adaptive neural network speed control scheme for an induction motor (IM) drive. The proposed scheme consists of an adaptive neural network identifier (ANNI) and an adaptive neural network controller (ANNC). For learning the quoted neural networks, a back propagation algorithm was used to automatically adjust the weights of the ANNI and ANNC in order to minimize the performance functions. Here, the ANNI can quickly estimate the plant parameters and the ANNC is used to provide on-line identification of the command and to produce a control force, such that the motor speed can accurately track the reference command. By combining artificial neural network techniques with fuzzy logic concept, a neural and fuzzy adaptive control scheme is developed. Fuzzy logic was used for the adaptation of the neural controller to improve the robustness of the generated command. The developed method is robust to load torque disturbance and the speed target variations when it ensures precise trajectory tracking with the prescribed dynamics. The algorithm was verified by simulation and the results obtained demonstrate the effectiveness of the IM designed controller

  11. Control difuso de un motor de inducción

    Directory of Open Access Journals (Sweden)

    Agustín Garzón Carbonell

    2011-02-01

    Full Text Available Se presenta la simulación de un esquema de control de velocidad de un motor de inducción en coordenadas decampo, con controlador difuso sin la necesidad de realizar las compensaciones en los ejes d-q, lo que simplificasustancialmente el control. La inferencia difusa se implementó por el método de mínimo máximo. Para eldesemborronado, el método del centro de gravedad. Se muestra el comportamiento del sistema de controlsometido a cambios bruscos de carga y referencia, observándose la robustez del control difuso frente a un PIDclásico.  In this article the simulation  of speed control  of  induction motor is presented in field coordinates with fuzzycontroller without the necessity of carrying out the compensations in the d-q axes, simplifying substantially thecontrol. The diffuse inference was implemented by the maximum minimum method. For defuzzification, themethod of the center of gravity is used. The system behaviour is shown from control to abrupt changes of loadand it indexes being observed the robustness of the diffuse control in front of a classic PID.

  12. Technology for Children With Brain Injury and Motor Disability: Executive Summary From Research Summit IV.

    Science.gov (United States)

    Christy, Jennifer B; Lobo, Michele A; Bjornson, Kristie; Dusing, Stacey C; Field-Fote, Edelle; Gannotti, Mary; Heathcock, Jill C; OʼNeil, Margaret E; Rimmer, James H

    Advances in technology show promise as tools to optimize functional mobility, independence, and participation in infants and children with motor disability due to brain injury. Although technologies are often used in adult rehabilitation, these have not been widely applied to rehabilitation of infants and children. In October 2015, the Academy of Pediatric Physical Therapy sponsored Research Summit IV, "Innovations in Technology for Children With Brain Insults: Maximizing Outcomes." The summit included pediatric physical therapist researchers, experts from other scientific fields, funding agencies, and consumers. Participants identified challenges in implementing technology in pediatric rehabilitation including accessibility, affordability, managing large data sets, and identifying relevant data elements. Participants identified 4 key areas for technology development: to determine (1) thresholds for learning, (2) appropriate transfer to independence, (3) optimal measurement of subtle changes, and (4) how to adapt to growth and changing abilities.

  13. DNA-assisted swarm control in a biomolecular motor system.

    Science.gov (United States)

    Keya, Jakia Jannat; Suzuki, Ryuhei; Kabir, Arif Md Rashedul; Inoue, Daisuke; Asanuma, Hiroyuki; Sada, Kazuki; Hess, Henry; Kuzuya, Akinori; Kakugo, Akira

    2018-01-31

    In nature, swarming behavior has evolved repeatedly among motile organisms because it confers a variety of beneficial emergent properties. These include improved information gathering, protection from predators, and resource utilization. Some organisms, e.g., locusts, switch between solitary and swarm behavior in response to external stimuli. Aspects of swarming behavior have been demonstrated for motile supramolecular systems composed of biomolecular motors and cytoskeletal filaments, where cross-linkers induce large scale organization. The capabilities of such supramolecular systems may be further extended if the swarming behavior can be programmed and controlled. Here, we demonstrate that the swarming of DNA-functionalized microtubules (MTs) propelled by surface-adhered kinesin motors can be programmed and reversibly regulated by DNA signals. Emergent swarm behavior, such as translational and circular motion, can be selected by tuning the MT stiffness. Photoresponsive DNA containing azobenzene groups enables switching between solitary and swarm behavior in response to stimulation with visible or ultraviolet light.

  14. Voice-controlled Internet Browsing for Motor-handicapped Users

    DEFF Research Database (Denmark)

    Brøndsted, Tom; Aaskoven, Erik

    2006-01-01

    The public-funded project "Indtal" ("Speak-it") has succeeded in developing a Danish voice-controlled utility for internet browsing targeting motor-handicapped users having difficulties using a standard keyboard and/or a standard mouse. The system has been designed and implemented in collaboration...... with an advisory board of motor-handicapped (potential) end-users and underlies a number of a priori defined design criteria: learnability and memorability rather than naturalness, minimal need for maintenance after release, support for "all" web standards (not just HTML conforming to certain "recommendations......"), independency of the language on the websites being browsed, etc. These criteria have lead to a primarily message-driven system interacting with an existing browser on the end users' systems...

  15. Modelling and control system of multi motor conveyor

    Science.gov (United States)

    Kovalchuk, M. S.; Baburin, S. V.

    2018-03-01

    The paper deals with the actual problem of developing the mathematical model of electromechanical system: conveyor – multimotor electric drive with a frequency converter, with the implementation in Simulink/MatLab, which allows one to perform studies of conveyor operation modes, taking into account the specifics of the mechanism with different electric drives control algorithms. The authors designed the mathematical models of the conveyor and its control system that provides increased uniformity of load distribution between drive motors and restriction of dynamic loads on the belt (over-regulation until 15%).

  16. Neurofeedback fMRI-mediated learning and consolidation of regional brain activation during motor imagery

    Science.gov (United States)

    Yoo, Seung-Schik; Lee, Jong-Hwan; O’Leary, Heather; Panych, Lawrence P.; Jolesz, Ferenc A.

    2009-01-01

    We report the long-term effect of real-time functional MRI (rtfMRI) training on voluntary regulation of the level of activation from a hand motor area. During the performance of a motor imagery task of a right hand, blood-oxygenation-level-dependent (BOLD) signal originating from a primary motor area was presented back to the subject in real-time. Demographically matched individuals also received the same procedure without valid feedback information. Followed by the initial rtfMRI sessions, both groups underwent two-week long, daily-practice of the task. Off-line data analysis revealed that the individuals in the experimental group were able to increase the level of BOLD signal from the regulatory target to a greater degree compared to the control group. Furthermore, the learned level of activation was maintained after the two-week period, with the recruitment of additional neural circuitries such as the hippocampus and the limbo-thalamo-cortical pathway. The activation obtained from the control group, in the absence of proper feedback, was indifferent across the training conditions. The level of BOLD activity from the target regulatory region was positively correlated with a self evaluative score within the experimental group, while the majority of control subjects had difficulty adopting a strategy to attain the desired level of functional regulation. Our results suggest that rtfMRI helped individuals learn how to increase region-specific cortical activity associated with a motor imagery task, and the level of increased activation in motor areas was consolidated after the two-week self-practice period, with the involvement of neural circuitries implicated in motor skill learning. PMID:19526048

  17. Environmentally relevant pyrethroid mixtures: A study on the correlation of blood and brain concentrations of a mixture of pyrethroid insecticides to motor activity in the rat.

    Science.gov (United States)

    Hughes, Michael F; Ross, David G; Starr, James M; Scollon, Edward J; Wolansky, Marcelo J; Crofton, Kevin M; DeVito, Michael J

    2016-06-01

    Human exposure to multiple pyrethroid insecticides may occur because of their broad use on crops and for residential pest control. To address the potential health risk from co-exposure to pyrethroids, it is important to understand their disposition and toxicity in target organs such as the brain, and surrogates such as the blood when administered as a mixture. The objective of this study was to assess the correlation between blood and brain concentrations of pyrethroids and neurobehavioral effects in the rat following an acute oral administration of the pyrethroids as a mixture. Male Long-Evans rats were administered a mixture of β-cyfluthrin, cypermethrin, deltamethrin, esfenvalerate and cis- and trans-permethrin in corn oil at seven dose levels. The pyrethroid with the highest percentage in the dosing solution was trans-permethrin (31% of total mixture dose) while deltamethrin and esfenvalerate had the lowest percentage (3%). Motor activity of the rats was then monitored for 1h. At 3.5h post-dosing, the animals were euthanized and blood and brain were collected. These tissues were extracted and analyzed for parent pyrethroid using HPLC-tandem mass spectrometry. Cypermethrin and cis-permethrin were the predominate pyrethroids detected in blood and brain, respectively, at all dosage levels. The relationship of total pyrethroid concentration between blood and brain was linear (r=0.93). The pyrethroids with the lowest fraction in blood were trans-permethrin and β-cyfluthrin and in brain were deltamethrin and esfenvalerate. The relationship between motor activity of the treated rats and summed pyrethroid blood and brain concentration was described using a sigmoidal Emax model with the Effective Concentration50 being more sensitive for brain than blood. The data suggests summed pyrethroid rat blood concentration could be used as a surrogate for brain concentration as an aid to study the neurotoxic effects of pyrethroids administered as a mixture under the conditions

  18. When "altering brain function" becomes "mind control".

    Science.gov (United States)

    Koivuniemi, Andrew; Otto, Kevin

    2014-01-01

    Functional neurosurgery has seen a resurgence of interest in surgical treatments for psychiatric illness. Deep brain stimulation (DBS) technology is the preferred tool in the current wave of clinical experiments because it allows clinicians to directly alter the functions of targeted brain regions, in a reversible manner, with the intent of correcting diseases of the mind, such as depression, addiction, anorexia nervosa, dementia, and obsessive compulsive disorder. These promising treatments raise a critical philosophical and humanitarian question. "Under what conditions does 'altering brain function' qualify as 'mind control'?" In order to answer this question one needs a definition of mind control. To this end, we reviewed the relevant philosophical, ethical, and neurosurgical literature in order to create a set of criteria for what constitutes mind control in the context of DBS. We also outline clinical implications of these criteria. Finally, we demonstrate the relevance of the proposed criteria by focusing especially on serendipitous treatments involving DBS, i.e., cases in which an unintended therapeutic benefit occurred. These cases highlight the importance of gaining the consent of the subject for the new therapy in order to avoid committing an act of mind control.

  19. Evaluation of a modified Fitts law brain-computer interface target acquisition task in able and motor disabled individuals

    Science.gov (United States)

    Felton, E. A.; Radwin, R. G.; Wilson, J. A.; Williams, J. C.

    2009-10-01

    A brain-computer interface (BCI) is a communication system that takes recorded brain signals and translates them into real-time actions, in this case movement of a cursor on a computer screen. This work applied Fitts' law to the evaluation of performance on a target acquisition task during sensorimotor rhythm-based BCI training. Fitts' law, which has been used as a predictor of movement time in studies of human movement, was used here to determine the information transfer rate, which was based on target acquisition time and target difficulty. The information transfer rate was used to make comparisons between control modalities and subject groups on the same task. Data were analyzed from eight able-bodied and five motor disabled participants who wore an electrode cap that recorded and translated their electroencephalogram (EEG) signals into computer cursor movements. Direct comparisons were made between able-bodied and disabled subjects, and between EEG and joystick cursor control in able-bodied subjects. Fitts' law aptly described the relationship between movement time and index of difficulty for each task movement direction when evaluated separately and averaged together. This study showed that Fitts' law can be successfully applied to computer cursor movement controlled by neural signals.

  20. Identification and robust control of an experimental servo motor.

    Science.gov (United States)

    Adam, E J; Guestrin, E D

    2002-04-01

    In this work, the design of a robust controller for an experimental laboratory-scale position control system based on a dc motor drive as well as the corresponding identification and robust stability analysis are presented. In order to carry out the robust design procedure, first, a classic closed-loop identification technique is applied and then, the parametrization by internal model control is used. The model uncertainty is evaluated under both parametric and global representation. For the latter case, an interesting discussion about the conservativeness of this description is presented by means of a comparison between the uncertainty disk and the critical perturbation radius approaches. Finally, conclusions about the performance of the experimental system with the robust controller are discussed using comparative graphics of the controlled variable and the Nyquist stability margin as a robustness measurement.

  1. Robust Adaptive Speed Control of Induction Motor Drives

    DEFF Research Database (Denmark)

    Bidstrup, N.

    This thesis concerns speed control of current vector controlled induction motor drives (CVC drives). The CVC drive is an existing prototype drive developed by Danfoss A/S, Transmission Division. Practical tests have revealed that the open loop dynamical properties of the CVC drive are highly......, (LS) identification and generalized predictive control (GPC) has been implemented and tested on the CVC drive. Allthough GPC is a robust control method, it was not possible to maintain specified controller performance in the entire operating range. This was the main reason for investigating truly...... and measurement noise in general, were the major reasons for the drifting parameters. Two approaches was proposed to robustify MASTR2 against the output noise. The first approach consists of filtering the output. Output filtering had a significant effect in simulations, but the robustness against the output noise...

  2. LINKING MOTOR-RELATED BRAIN POTENTIALS AND VELOCITY PROFILES IN MULTI-JOINT ARM REACHING MOVEMENTS

    Directory of Open Access Journals (Sweden)

    Julià L Amengual

    2014-04-01

    Full Text Available The study of the movement related brain potentials (MRPBs needs accurate technical approaches to disentangle the specific patterns of bran activity during the preparation and execution of movements. During the last forty years, synchronizing the electromiographic activation (EMG of the muscle with the electrophysiological recordings (EEG has been commonly ussed for these purposes. However, new clinical approaches in the study of motor diseases and rehabilitation suggest the demand of new paradigms that might go further into the study of the brain activity associated with the kinematics of movement. As a response to this call, we have used a 3-D hand tracking system with the aim to record continuously the position of an ultrasonic sender located on the hand during the performance of multi-joint self-pace movements. We synchronized the time-series of position of velocity of the sender with the EEG recordings, obtaining specific patterns of brain activity as a function of the fluctuations of the kinematics during the natural movement performance. Additionally, the distribution of the brain activity during the preparation and execution phases of movement was similar that reported previously using the EMG, suggesting the validity of our technique. We claim that this paradigm could be usable in patients because of its simplicity and the potential knowledge that can be extracted from clinical protocols.

  3. What is the evidence of impaired motor skills and motor control among children with attention deficit hyperactivity disorder (ADHD)? Systematic review of the literature.

    Science.gov (United States)

    Kaiser, M-L; Schoemaker, M M; Albaret, J-M; Geuze, R H

    2014-11-06

    This article presents a review of the studies that have analysed the motor skills of ADHD children without medication and the influence of medication on their motor skills. The following two questions guided the study: What is the evidence of impairment of motor skills and aspects of motor control among children with ADHD aged between 6 and 16 years? What are the effects of ADHD medication on motor skills and motor control? The following keywords were introduced in the main databases: attention disorder and/or ADHD, motor skills and/or handwriting, children, medication. Of the 45 articles retrieved, 30 described motor skills of children with ADHD and 15 articles analysed the influence of ADHD medication on motor skills and motor control. More than half of the children with ADHD have difficulties with gross and fine motor skills. The children with ADHD inattentive subtype seem to present more impairment of fine motor skills, slow reaction time, and online motor control during complex tasks. The proportion of children with ADHD who improved their motor skills to the normal range by using medication varied from 28% to 67% between studies. The children who still show motor deficit while on medication might meet the diagnostic criteria of developmental coordination disorder (DCD). It is important to assess motor skills among children with ADHD because of the risk of reduced participation in activities of daily living that require motor coordination and attention. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. The speed control of DC motor under the load condition using PI and PID controllers

    Science.gov (United States)

    Corapsiz, Muhammed Reşit; Kahveci, Hakan

    2017-04-01

    In this study, it was aimed to compare PI (Proportional-Integral) and PID (Proportional-Integral-Derivative) controllers for speed control of Permanent Magnet Direct Current (PMDC) motor under both load and without load. For this purpose, firstly, the mathematical model was obtained from the dynamic equations of the PMDC motor and the obtained mathematical model was transferred to the simulation environment and modeled using Matlab/SIMULINK. Following the modeling process, PI and PID controller structures were formed, respectively. Secondly, after these structures were formed, the PMDC motor was run without any controller. Then, the control of the PMDC motor with no load was provided by using PI and PID controllers. Finally, the PMDC motor were loaded under the constant load (TL = 3 N.m.) for each condition and selected time period (t = 3 s). The obtained result for each control operations was comparatively given by observing effects of loading process on systems. When the obtained results were evaluated for each condition, it was observed that PID controller have the best performance with respect to PI controller.

  5. Can a single session of motor imagery promote motor learning of locomotion in older adults? A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Nicholson VP

    2018-04-01

    Full Text Available Vaughan P Nicholson,1 Justin WL Keogh,2–4 Nancy L Low Choy1 1School of Physiotherapy, Australian Catholic University, Brisbane, QLD, Australia; 2Faculty of Health Sciences and Medicine, Bond University, Robina, QLD, Australia; 3Human Potential Centre, AUT University, Auckland, New Zealand; 4Cluster for Health Improvement, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sunshine Coast, QLD, Australia Purpose: To investigate the influence of a single session of locomotor-based motor imagery training on motor learning and physical performance. Patients and methods: Thirty independent adults aged >65 years took part in the randomized controlled trial. The study was conducted within an exercise science laboratory. Participants were randomly divided into three groups following baseline locomotor testing: motor imagery training, physical training, and control groups. The motor imagery training group completed 20 imagined repetitions of a locomotor task, the physical training group completed 20 physical repetitions of a locomotor task, and the control group spent 25 minutes playing mentally stimulating games on an iPad. Imagined and physical performance times were measured for each training repetition. Gait speed (preferred and fast, timed-up-and-go, gait variability and the time to complete an obstacle course were completed before and after the single training session. Results: Motor learning occurred in both the motor imagery training and physical training groups. Motor imagery training led to refinements in motor planning resulting in imagined movements better matching the physically performed movement at the end of training. Motor imagery and physical training also promoted improvements in some locomotion outcomes as demonstrated by medium to large effect size improvements after training for fast gait speed and timed-up-and-go. There were no training effects on gait variability. Conclusion: A single session

  6. Robust tactile sensory responses in finger area of primate motor cortex relevant to prosthetic control

    Science.gov (United States)

    Schroeder, Karen E.; Irwin, Zachary T.; Bullard, Autumn J.; Thompson, David E.; Bentley, J. Nicole; Stacey, William C.; Patil, Parag G.; Chestek, Cynthia A.

    2017-08-01

    Objective. Challenges in improving the performance of dexterous upper-limb brain-machine interfaces (BMIs) have prompted renewed interest in quantifying the amount and type of sensory information naturally encoded in the primary motor cortex (M1). Previous single unit studies in monkeys showed M1 is responsive to tactile stimulation, as well as passive and active movement of the limbs. However, recent work in this area has focused primarily on proprioception. Here we examined instead how tactile somatosensation of the hand and fingers is represented in M1. Approach. We recorded multi- and single units and thresholded neural activity from macaque M1 while gently brushing individual finger pads at 2 Hz. We also recorded broadband neural activity from electrocorticogram (ECoG) grids placed on human motor cortex, while applying the same tactile stimulus. Main results. Units displaying significant differences in firing rates between individual fingers (p  sensory information was present in M1 to correctly decode stimulus position from multiunit activity above chance levels in all monkeys, and also from ECoG gamma power in two human subjects. Significance. These results provide some explanation for difficulties experienced by motor decoders in clinical trials of cortically controlled prosthetic hands, as well as the general problem of disentangling motor and sensory signals in primate motor cortex during dextrous tasks. Additionally, examination of unit tuning during tactile and proprioceptive inputs indicates cells are often tuned differently in different contexts, reinforcing the need for continued refinement of BMI training and decoding approaches to closed-loop BMI systems for dexterous grasping.

  7. Energy efficiency in speed control system for induction motors; Eficiencia energetica em sistema de controle de velocidade em motores de inducao

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Arlete Vieira da; Ribeiro, Elisangela do Nascimento; Tenorio, Iana Cavalcanti; Horta, Mario Marcos Brito [Centro Universitario de Belo Horizonte (UnBH), MG (Brazil)], e-mails: arlete.silva@prof.unibh.br, nr.elisangela@gmail.com, ianactenorio@gmail.com, mario_bhorta@yahoo.com.br

    2011-07-01

    This work has as objective the study of energy efficiency of induction motors fed by frequency inverters, since this is a practical resource that has progressively allowed the replacement of mechanical speed reducers. In this work the speed control of induction motors of the squirrel cage has steeped through the frequency inverters using scalar control. Induction motors are frequently used in industrial applications due to its simple construction, its low maintenance and reduced in size. It was possible through tests made at UNI-BH Electrical Engineering laboratory to obtain satisfactory results regarding the performance of the inverter CFW08 (WEG), speed control of induction motor. (author)

  8. Robot-assisted motor activation monitored by time-domain optical brain imaging

    Science.gov (United States)

    Steinkellner, O.; Wabnitz, H.; Schmid, S.; Steingräber, R.; Schmidt, H.; Krüger, J.; Macdonald, R.

    2011-07-01

    Robot-assisted motor rehabilitation proved to be an effective supplement to conventional hand-to-hand therapy in stroke patients. In order to analyze and understand motor learning and performance during rehabilitation it is desirable to develop a monitor to provide objective measures of the corresponding brain activity at the rehabilitation progress. We used a portable time-domain near-infrared reflectometer to monitor the hemodynamic brain response to distal upper extremity activities. Four healthy volunteers performed two different robot-assisted wrist/forearm movements, flexion-extension and pronation-supination in comparison with an unassisted squeeze ball exercise. A special headgear with four optical measurement positions to include parts of the pre- and postcentral gyrus provided a good overlap with the expected activation areas. Data analysis based on variance of time-of-flight distributions of photons through tissue was chosen to provide a suitable representation of intracerebral signals. In all subjects several of the four detection channels showed a response. In some cases indications were found of differences in localization of the activated areas for the various tasks.

  9. Whole-brain functional magnetic resonance imaging of cerebral arteriovenous malformations involving the motor pathways

    International Nuclear Information System (INIS)

    Ozdoba, C.; Remonda, L.; Loevblad, K.O.; Schroth, G.; Nirkko, A.C.

    2002-01-01

    To investigate cortical, basal ganglia and cerebellar activation in patients with arteriovenous malformations (AVMs) involving the motor pathways, we studied ten patients (six male, four female, mean age 30.3 years, range 7.4-44.1) by whole-brain functional magnetic resonance imaging (fMRI) in a 1.5-T scanner with the EPI-BOLD-technique. In seven cases multiple fMRI studies were available, acquired in the course of the multi-session endovascular interventional treatment. Self-paced right- and left-handed finger-tapping tasks were used to invoke activation. In six patients a super-selective amytal test (Wada test) was performed during diagnostic pre-interventional angiography studies. Abnormal cortical activation patterns, with activation of the primary sensorimotor area, the supplementary motor area and/or the cerebellum shifted to unphysiological locations, were found in four patients. In all cases, localization of the AVM could account for the changes from the normal. After endovascular procedures, fMRI demonstrated shifts in the activation pattern in three patients. In the six patients that had undergone fMRI studies and the Wada test, both methods yielded comparable results. The fact that AVMs are structural anomalies for which the brain can partly compensate ('plasticity') was underlined by these results. fMRI is a valuable tool in the pre-therapeutic evaluation and post-interventional follow-up of patients with cerebral AVMs in whom an operation or an endovascular procedure is planned. (orig.)

  10. Motor and non-motor features of Parkinson's disease in LRRK2 G2019S carriers versus matched controls.

    Science.gov (United States)

    Gunzler, Steven A; Riley, David E; Chen, Shu G; Tatsuoka, Curtis M; Johnson, William M; Mieyal, John J; Walter, Ellen M; Whitney, Christina M; Feng, I Jung; Owusu-Dapaah, Harry; Mittal, Shivam O; Wilson-Delfosse, Amy L

    2018-05-15

    LRRK2 G2019S mutation carriers with Parkinson's disease (PD) have been generally indistinguishable from those with idiopathic PD, with the exception of variable differences in some motor and non-motor domains, including cognition, gait, and balance. LRRK2 G2019S is amongst the most common genetic etiologies for PD, particularly in Ashkenazi Jewish (AJ) populations. This cross-sectional data collection study sought to clarify the phenotype of LRRK2 G2019S mutation carriers with PD. Primary endpoints were the Movement Disorder Society Unified Parkinson Disease Rating Scale (MDS-UPDRS) and Montreal Cognitive Assessment (MoCA). Other motor and non-motor data were also assessed. The Mann-Whitney U Test was utilized to compare LRRK2 G2019S carriers with PD (LRRK2+) with non-carrier PD controls who were matched for age, gender, education, and PD duration. Survival analyses and log rank tests were utilized to compare interval from onset of PD to development of motor and non-motor complications. We screened 251 subjects and 231 completed the study, of whom 9 were LRRK2+, including 7 AJ subjects. 22.73% of AJ subjects with a family history of PD (FH) and 12.96% of AJ subjects without a FH were LRRK2+. There were no significant differences between the 9 LRRK2+ subjects and 19 matched PD controls in MDS-UPDRS, MoCA, or other motor and non-motor endpoints. Prevalence of the LRRK2 G2019S mutation in AJ and non-AJ subjects in our study population in Cleveland, Ohio was comparable to other clinical studies. There were no significant motor or non-motor differences between LRRK2+ PD and matched PD controls. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Electrical stimulation of motor cortex in the uninjured hemisphere after chronic unilateral injury promotes recovery of skilled locomotion through ipsilateral control.

    Science.gov (United States)

    Carmel, Jason B; Kimura, Hiroki; Martin, John H

    2014-01-08

    Partial injury to the corticospinal tract (CST) causes sprouting of intact axons at their targets, and this sprouting correlates with functional improvement. Electrical stimulation of motor cortex augments sprouting of intact CST axons and promotes functional recovery when applied soon after injury. We hypothesized that electrical stimulation of motor cortex in the intact hemisphere after chronic lesion of the CST in the other hemisphere would restore function through ipsilateral control. To test motor skill, rats were trained and tested to walk on a horizontal ladder with irregularly spaced rungs. Eight weeks after injury, produced by pyramidal tract transection, half of the rats received forelimb motor cortex stimulation of the intact hemisphere. Rats with injury and stimulation had significantly improved forelimb control compared with rats with injury alone and achieved a level of proficiency similar to uninjured rats. To test whether recovery of forelimb function was attributable to ipsilateral control, we selectively inactivated the stimulated motor cortex using the GABA agonist muscimol. The dose of muscimol we used produces strong contralateral but no ipsilateral impairments in naive rats. In rats with injury and stimulation, but not those with injury alone, inactivation caused worsening of forelimb function; the initial deficit was reinstated. These results demonstrate that electrical stimulation can promote recovery of motor function when applied late after injury and that motor control can be exerted from the ipsilateral motor cortex. These results suggest that the uninjured motor cortex could be targeted for brain stimulation in people with large unilateral CST lesions.

  12. Hand grips strength effect on motor function in human brain using fMRI: a pilot study

    International Nuclear Information System (INIS)

    Ismail, S S; Mohamad, M; Syazarina, S O; Nafisah, W Y

    2014-01-01

    Several methods of motor tasks for fMRI scanning have been evolving from simple to more complex tasks. Motor tasks on upper extremity were applied in order to excite the increscent of motor activation on contralesional and ipsilateral hemispheres in brain. The main objective of this study is to study the different conditions for motor tasks on upper extremity that affected the brain activation. Ten healthy right handed with normal vision (3 male and 7 female, age range=20-30 years, mean=24.6 years, SD=2.21) participated in this study. Prior to the scanning, participants were trained on hand grip tasks using rubber ball and pressure gauge tool outside the scanner. During fMRI session, a block design with 30-s task blocks and alternating 30-s rest periods was employed while participants viewed a computer screen via a back projection-mirror system and instructed to follow the instruction by gripping their hand with normal and strong grips using a rubber ball. Statistical Parametric mapping (SPM8) software was used to determine the brain activation. Both tasks activated the primary motor (M1), supplementary motor area (SMA), dorsal and ventral of premotor cortex area (PMA) in left hemisphere while in right hemisphere the area of primary motor (M1) somatosensory was activated. However, the comparison between both tasks revealed that the strong hand grip showed the higher activation at M1, PMA and SMA on left hemisphere and also the area of SMA on right hemisphere. Both conditions of motor tasks could provide insights the functional organization on human brain

  13. Hand grips strength effect on motor function in human brain using fMRI: a pilot study

    Science.gov (United States)

    Ismail, S. S.; Mohamad, M.; Syazarina, S. O.; Nafisah, W. Y.

    2014-11-01

    Several methods of motor tasks for fMRI scanning have been evolving from simple to more complex tasks. Motor tasks on upper extremity were applied in order to excite the increscent of motor activation on contralesional and ipsilateral hemispheres in brain. The main objective of this study is to study the different conditions for motor tasks on upper extremity that affected the brain activation. Ten healthy right handed with normal vision (3 male and 7 female, age range=20-30 years, mean=24.6 years, SD=2.21) participated in this study. Prior to the scanning, participants were trained on hand grip tasks using rubber ball and pressure gauge tool outside the scanner. During fMRI session, a block design with 30-s task blocks and alternating 30-s rest periods was employed while participants viewed a computer screen via a back projection-mirror system and instructed to follow the instruction by gripping their hand with normal and strong grips using a rubber ball. Statistical Parametric mapping (SPM8) software was used to determine the brain activation. Both tasks activated the primary motor (M1), supplementary motor area (SMA), dorsal and ventral of premotor cortex area (PMA) in left hemisphere while in right hemisphere the area of primary motor (M1) somatosensory was activated. However, the comparison between both tasks revealed that the strong hand grip showed the higher activation at M1, PMA and SMA on left hemisphere and also the area of SMA on right hemisphere. Both conditions of motor tasks could provide insights the functional organization on human brain.

  14. Brain-computer interface analysis of a dynamic visuo-motor task.

    Science.gov (United States)

    Logar, Vito; Belič, Aleš

    2011-01-01

    The area of brain-computer interfaces (BCIs) represents one of the more interesting fields in neurophysiological research, since it investigates the development of the machines that perform different transformations of the brain's "thoughts" to certain pre-defined actions. Experimental studies have reported some successful implementations of BCIs; however, much of the field still remains unexplored. According to some recent reports the phase coding of informational content is an important mechanism in the brain's function and cognition, and has the potential to explain various mechanisms of the brain's data transfer, but it has yet to be scrutinized in the context of brain-computer interface. Therefore, if the mechanism of phase coding is plausible, one should be able to extract the phase-coded content, carried by brain signals, using appropriate signal-processing methods. In our previous studies we have shown that by using a phase-demodulation-based signal-processing approach it is possible to decode some relevant information on the current motor action in the brain from electroencephalographic (EEG) data. In this paper the authors would like to present a continuation of their previous work on the brain-information-decoding analysis of visuo-motor (VM) tasks. The present study shows that EEG data measured during more complex, dynamic visuo-motor (dVM) tasks carries enough information about the currently performed motor action to be successfully extracted by using the appropriate signal-processing and identification methods. The aim of this paper is therefore to present a mathematical model, which by means of the EEG measurements as its inputs predicts the course of the wrist movements as applied by each subject during the task in simulated or real time (BCI analysis). However, several modifications to the existing methodology are needed to achieve optimal decoding results and a real-time, data-processing ability. The information extracted from the EEG could

  15. Neural control of finger movement via intracortical brain-machine interface

    Science.gov (United States)

    Irwin, Z. T.; Schroeder, K. E.; Vu, P. P.; Bullard, A. J.; Tat, D. M.; Nu, C. S.; Vaskov, A.; Nason, S. R.; Thompson, D. E.; Bentley, J. N.; Patil, P. G.; Chestek, C. A.

    2017-12-01

    Objective. Intracortical brain-machine interfaces (BMIs) are a promising source of prosthesis control signals for individuals with severe motor disabilities. Previous BMI studies have primarily focused on predicting and controlling whole-arm movements; precise control of hand kinematics, however, has not been fully demonstrated. Here, we investigate the continuous decoding of precise finger movements in rhesus macaques. Approach. In order to elicit precise and repeatable finger movements, we have developed a novel behavioral task paradigm which requires the subject to acquire virtual fingertip position targets. In the physical control condition, four rhesus macaques performed this task by moving all four fingers together in order to acquire a single target. This movement was equivalent to controlling the aperture of a power grasp. During this task performance, we recorded neural spikes from intracortical electrode arrays in primary motor cortex. Main results. Using a standard Kalman filter, we could reconstruct continuous finger movement offline with an average correlation of ρ  =  0.78 between actual and predicted position across four rhesus macaques. For two of the monkeys, this movement prediction was performed in real-time to enable direct brain control of the virtual hand. Compared to physical control, neural control performance was slightly degraded; however, the monkeys were still able to successfully perform the task with an average target acquisition rate of 83.1%. The monkeys’ ability to arbitrarily specify fingertip position was also quantified using an information throughput metric. During brain control task performance, the monkeys achieved an average 1.01 bits s-1 throughput, similar to that achieved in previous studies which decoded upper-arm movements to control computer cursors using a standard Kalman filter. Significance. This is, to our knowledge, the first demonstration of brain control of finger-level fine motor skills. We believe

  16. Control And Monitoring Of Controller Area Network Based Motor And Sensor Boards

    Directory of Open Access Journals (Sweden)

    Kubilay Taşdelen

    2018-06-01

    Full Text Available Remote control system also can use to provide the control of devices that are used in industrial environments nowadays. In this study, three experimental modules and one master module have been developed by using Arduino development board. These modules include sensors and motors. Experimental modules are controlled remotely through Android based application software, running on a smart phone. Bluetooth technology is used for this application. The connection between the experimental modules and master module are provided with Controller Area Network. In this way, the sensor and motor data are transmitted by serial communication.

  17. Non-stationary discharge patterns in motor cortex under subthalamic nucleus deep brain stimulation.

    Science.gov (United States)

    Santaniello, Sabato; Montgomery, Erwin B; Gale, John T; Sarma, Sridevi V

    2012-01-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) directly modulates the basal ganglia (BG), but how such stimulation impacts the cortex upstream is largely unknown. There is evidence of cortical activation in 6-hydroxydopamine (OHDA)-lesioned rodents and facilitation of motor evoked potentials in Parkinson's disease (PD) patients, but the impact of the DBS settings on the cortical activity in normal vs. Parkinsonian conditions is still debated. We use point process models to analyze non-stationary activation patterns and inter-neuronal dependencies in the motor and sensory cortices of two non-human primates during STN DBS. These features are enhanced after treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which causes a consistent PD-like motor impairment, while high-frequency (HF) DBS (i.e., ≥100 Hz) strongly reduces the short-term patterns (period: 3-7 ms) both before and after MPTP treatment, and elicits a short-latency post-stimulus activation. Low-frequency DBS (i.e., ≤50 Hz), instead, has negligible effects on the non-stationary features. Finally, by using tools from the information theory [i.e., receiver operating characteristic (ROC) curve and information rate (IR)], we show that the predictive power of these models is dependent on the DBS settings, i.e., the probability of spiking of the cortical neurons (which is captured by the point process models) is significantly conditioned on the timely delivery of the DBS input. This dependency increases with the DBS frequency and is significantly larger for high- vs. low-frequency DBS. Overall, the selective suppression of non-stationary features and the increased modulation of the spike probability suggest that HF STN DBS enhances the neuronal activation in motor and sensory cortices, presumably because of reinforcement mechanisms, which perhaps involve the overlap between feedback antidromic and feed-forward orthodromic responses along the BG-thalamo-cortical loop.

  18. Non-invasive brain stimulation for fine motor improvement after stroke: a meta-analysis.

    Science.gov (United States)

    O'Brien, A T; Bertolucci, F; Torrealba-Acosta, G; Huerta, R; Fregni, F; Thibaut, A

    2018-05-09

    The aim of this study was to determine whether non-invasive brain stimulation (NIBS) techniques improve fine motor performance in stroke. We searched PubMed, EMBASE, Web of Science, SciELO and OpenGrey for randomized clinical trials on NIBS for fine motor performance in stroke patients and healthy participants. We computed Hedges' g for active and sham groups, pooled data as random-effects models and performed sensitivity analysis on chronicity, montage, frequency of stimulation and risk of bias. Twenty-nine studies (351 patients and 152 healthy subjects) were reviewed. Effect sizes in stroke populations for transcranial direct current stimulation and repeated transcranial magnetic stimulation were 0.31 [95% confidence interval (CI), 0.08-0.55; P = 0.010; Tau 2 , 0.09; I 2 , 34%; Q, 18.23; P = 0.110] and 0.46 (95% CI, 0.00-0.92; P = 0.05; Tau 2 , 0.38; I 2 , 67%; Q, 30.45; P = 0.007). The effect size of non-dominant healthy hemisphere transcranial direct current stimulation on non-dominant hand function was 1.25 (95% CI, 0.09-2.41; P = 0.04; Tau 2 , 1.26; I 2 , 93%; Q, 40.27; P < 0.001). Our results show that NIBS is associated with gains in fine motor performance in chronic stroke patients and healthy subjects. This supports the effects of NIBS on motor learning and encourages investigation to optimize their effects in clinical and research settings. © 2018 EAN.

  19. What is the evidence of impaired motor skills and motor control among children with attention deficit hyperactivity disorder (ADHD)? Systematic review of the literature

    NARCIS (Netherlands)

    Kaiser, Marie-Laure; Schoemaker, M M; Albaret, J-M; Geuze, R H

    This article presents a review of the studies that have analysed the motor skills of ADHD children without medication and the influence of medication on their motor skills. The following two questions guided the study: What is the evidence of impairment of motor skills and aspects of motor control

  20. Control of Position for a Telescope with Stepping Motors

    OpenAIRE

    Quintero Salazar, Edwin Andrés; Gallego Becerra, Hugo Armando; Gallego Orozco, Hoover

    2008-01-01

    En este documento se muestran los resultados obtenidos al construir un control electrónico de posición para un telescopio reflector de 15 cm de objetivo, con motores paso a paso manejados desde un microcontrolador. También se ilustra el diseño circuital realizado, la simulación obtenida en la herramienta informática Proteus, el software desarrollado en lenguaje ensamblador para el microcontrolador, y el circuito final resultante montado sobre protoboard. In this paper the obtained resul...

  1. The Speed Control of Constant Tension Motor of Marine Crane

    Directory of Open Access Journals (Sweden)

    Chen Xinyang

    2016-01-01

    Full Text Available This article describes the working principle of the marine beacon crane hanging disc mechanical anti-sway device, and establish mathematical model on the rope controlling hanging disc of mechanical anti-sway device; Through matlab simulation analysis, this article obtains the relation curve between the velocity of traction rope of hanging disc and output frequency of the crane motor, combining rotary crane scaled model, this article carries out anti-sway experiment for the rotary crane to examine the crane’s anti-sway effects.

  2. The Changes in the Hemodynamic Activity of the Brain during Motor Imagery Training with the Use of Brain-Computer Interface

    Czech Academy of Sciences Publication Activity Database

    Frolov, A. A.; Húsek, Dušan; Silchenko, A.V.; Tintěra, J.; Rydlo, J.

    2016-01-01

    Roč. 42, č. 1 (2016), s. 1-12 ISSN 0362-1197 R&D Projects: GA MŠk ED1.1.00/02.0070 Grant - others:GA MŠk(CZ) EE.2.3.20.0073 Institutional support: RVO:67985807 Keywords : brain-computer interface * motor imagery * hemodynamic activity * brain plasticity * functional MRI Subject RIV: IN - Informatics, Computer Science

  3. Probabilistic fiber tracking of the language and motor white matter pathways of the supplementary motor area (SMA) in patients with brain tumors.

    Science.gov (United States)

    Jenabi, Mehrnaz; Peck, Kyung K; Young, Robert J; Brennan, Nicole; Holodny, Andrei I

    2014-12-01

    Accurate localization of anatomically and functionally separate SMA tracts is important to improve planning prior to neurosurgery. Using fMRI and probabilistic DTI techniques, we assessed the connectivity between the frontal language area (Broca's area) and the rostral pre-SMA (language SMA) and caudal SMA proper (motor SMA). Twenty brain tumor patients completed motor and language fMRI paradigms and DTI. Peaks of functional activity in the language SMA, motor SMA and Broca's area were used to define seed regions for probabilistic tractography. fMRI and probabilistic tractography identified separate and unique pathways connecting the SMA to Broca's area - the language SMA pathway and the motor SMA pathway. For all subjects, the language SMA pathway had a larger number of voxels (PProbabilistic tractography can identify unique white matter tracts that connect language SMA and motor SMA to Broca's area. The language SMA is more significantly connected to Broca's area than is the motor subdivision of the SMA proper. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  4. Factors predicting the instant effect of motor function after subthalamic nucleus deep brain stimulation in Parkinson's disease.

    Science.gov (United States)

    Su, Xin-Ling; Luo, Xiao-Guang; Lv, Hong; Wang, Jun; Ren, Yan; He, Zhi-Yi

    2017-01-01

    Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for Parkinson's disease (PD), the predictive effect of levodopa responsiveness on surgical outcomes was confirmed by some studies, however there were different conclusions about that through long- and short-term follow-ups. We aimed to investigate the factors which influence the predictive value of levodopa responsiveness, and discover more predictive factors of surgical outcomes. Twenty-three PD patients underwent bilateral STN-DBS and completed our follow-up. Clinical evaluations were performed 1 week before and 3 months after surgery. STN-DBS significantly improved motor function of PD patients after 3 months; preoperative levodopa responsiveness and disease subtype predicted the effect of DBS on motor function; gender, disease duration and duration of motor fluctuations modified the predictive effect of levodopa responsiveness on motor improvement; the duration of motor fluctuations and severity of preoperative motor symptoms modified the predictive effect of disease subtype on motor improvement. The intensity of levodopa responsiveness served as a predictor of motor improvement more accurately in female patients, patients with shorter disease duration or shorter motor fluctuations; PD patients with dominant axial symptoms benefit less from STN-DBS compared to those with limb-predominant symptoms, especially in their later disease stage.

  5. Flexible brain network reconfiguration supporting inhibitory control.

    Science.gov (United States)

    Spielberg, Jeffrey M; Miller, Gregory A; Heller, Wendy; Banich, Marie T

    2015-08-11

    The ability to inhibit distracting stimuli from interfering with goal-directed behavior is crucial for success in most spheres of life. Despite an abundance of studies examining regional brain activation, knowledge of the brain networks involved in inhibitory control remains quite limited. To address this critical gap, we applied graph theory tools to functional magnetic resonance imaging data collected while a large sample of adults (n = 101) performed a color-word Stroop task. Higher demand for inhibitory control was associated with restructuring of the global network into a configuration that was more optimized for specialized processing (functional segregation), more efficient at communicating the output of such processing across the network (functional integration), and more resilient to potential interruption (resilience). In addition, there were regional changes with right inferior frontal sulcus and right anterior insula occupying more central positions as network hubs, and dorsal anterior cingulate cortex becoming more tightly coupled with its regional subnetwork. Given the crucial role of inhibitory control in goal-directed behavior, present findings identifying functional network organization supporting inhibitory control have the potential to provide additional insights into how inhibitory control may break down in a wide variety of individuals with neurological or psychiatric difficulties.

  6. Fluoxetine for motor recovery after acute ischaemic stroke (FLAME): a randomised placebo-controlled trial.

    Science.gov (United States)

    Chollet, François; Tardy, Jean; Albucher, Jean-François; Thalamas, Claire; Berard, Emilie; Lamy, Catherine; Bejot, Yannick; Deltour, Sandrine; Jaillard, Assia; Niclot, Philippe; Guillon, Benoit; Moulin, Thierry; Marque, Philippe; Pariente, Jérémie; Arnaud, Catherine; Loubinoux, Isabelle

    2011-02-01

    Hemiplegia and hemiparesis are the most common deficits caused by stroke. A few small clinical trials suggest that fluoxetine enhances motor recovery but its clinical efficacy is unknown. We therefore aimed to investigate whether fluoxetine would enhance motor recovery if given soon after an ischaemic stroke to patients who have motor deficits. In this double-blind, placebo-controlled trial, patients from nine stroke centres in France who had ischaemic stroke and hemiplegia or hemiparesis, had Fugl-Meyer motor scale (FMMS) scores of 55 or less, and were aged between 18 years and 85 years were eligible for inclusion. Patients were randomly assigned, using a computer random-number generator, in a 1:1 ratio to fluoxetine (20 mg once per day, orally) or placebo for 3 months starting 5-10 days after the onset of stroke. All patients had physiotherapy. The primary outcome measure was the change on the FMMS between day 0 and day 90 after the start of the study drug. Participants, carers, and physicians assessing the outcome were masked to group assignment. Analysis was of all patients for whom data were available (full analysis set). This trial is registered with ClinicalTrials.gov, number NCT00657163. 118 patients were randomly assigned to fluoxetine (n=59) or placebo (n=59), and 113 were included in the analysis (57 in the fluoxetine group and 56 in the placebo group). Two patients died before day 90 and three withdrew from the study. FMMS improvement at day 90 was significantly greater in the fluoxetine group (adjusted mean 34·0 points [95% CI 29·7-38·4]) than in the placebo group (24·3 points [19·9-28·7]; p=0·003). The main adverse events in the fluoxetine and placebo groups were hyponatraemia (two [4%] vs two [4%]), transient digestive disorders including nausea, diarrhoea, and abdominal pain (14 [25%] vs six [11%]), hepatic enzyme disorders (five [9%] vs ten [18%]), psychiatric disorders (three [5%] vs four [7%]), insomnia (19 [33%] vs 20 [36%]), and partial

  7. Design of permanent magnet synchronous motor speed loop controller based on sliding mode control algorithm

    Science.gov (United States)

    Qiang, Jiang; Meng-wei, Liao; Ming-jie, Luo

    2018-03-01

    Abstract.The control performance of Permanent Magnet Synchronous Motor will be affected by the fluctuation or changes of mechanical parameters when PMSM is applied as driving motor in actual electric vehicle,and external disturbance would influence control robustness.To improve control dynamic quality and robustness of PMSM speed control system, a new second order integral sliding mode control algorithm is introduced into PMSM vector control.The simulation results show that, compared with the traditional PID control,the modified control scheme optimized has better control precision and dynamic response ability and perform better with a stronger robustness facing external disturbance,it can effectively solve the traditional sliding mode variable structure control chattering problems as well.

  8. Disruption to functional networks in neonates with perinatal brain injury predicts motor skills at 8 months.

    Science.gov (United States)

    Linke, Annika C; Wild, Conor; Zubiaurre-Elorza, Leire; Herzmann, Charlotte; Duffy, Hester; Han, Victor K; Lee, David S C; Cusack, Rhodri

    2018-01-01

    Functional connectivity magnetic resonance imaging (fcMRI) of neonates with perinatal brain injury could improve prediction of motor impairment before symptoms manifest, and establish how early brain organization relates to subsequent development. This cohort study is the first to describe and quantitatively assess functional brain networks and their relation to later motor skills in neonates with a diverse range of perinatal brain injuries. Infants ( n  = 65, included in final analyses: n  = 53) were recruited from the neonatal intensive care unit (NICU) and were stratified based on their age at birth (premature vs. term), and on whether neuropathology was diagnosed from structural MRI. Functional brain networks and a measure of disruption to functional connectivity were obtained from 14 min of fcMRI acquired during natural sleep at term-equivalent age. Disruption to connectivity of the somatomotor and frontoparietal executive networks predicted motor impairment at 4 and 8 months. This disruption in functional connectivity was not found to be driven by differences between clinical groups, or by any of the specific measures we captured to describe the clinical course. fcMRI was predictive over and above other clinical measures available at discharge from the NICU, including structural MRI. Motor learning was affected by disruption to somatomotor networks, but also frontoparietal executive networks, which supports the functional importance of these networks in early development. Disruption to these two networks might be best addressed by distinct intervention strategies.

  9. Brushless DC motor control system responsive to control signals generated by a computer or the like

    Science.gov (United States)

    Packard, Douglas T. (Inventor); Schmitt, Donald E. (Inventor)

    1987-01-01

    A control system for a brushless DC motor responsive to digital control signals is disclosed. The motor includes a multiphase wound stator and a permanent magnet rotor. The rotor is arranged so that each phase winding, when energized from a DC source, will drive the rotor through a predetermined angular position or step. A commutation signal generator responsive to the shaft position provides a commutation signal for each winding. A programmable control signal generator such as a computer or microprocessor produces individual digital control signals for each phase winding. The control signals and commutation signals associated with each winding are applied to an AND gate for that phase winding. Each gate controls a switch connected in series with the associated phase winding and the DC source so that each phase winding is energized only when the commutation signal and the control signal associated with that phase winding are present. The motor shaft may be advanced one step at a time to a desired position by applying a predetermined number of control signals in the proper sequence to the AND gates and the torque generated by the motor may be regulated by applying a separate control signal to each AND gate which is pulse width modulated to control the total time that each switch connects its associated winding to the DC source during each commutation period.

  10. Central motor control failure in fibromyalgia: a surface electromyography study.

    Science.gov (United States)

    Casale, Roberto; Sarzi-Puttini, Piercarlo; Atzeni, Fabiola; Gazzoni, Marco; Buskila, Dan; Rainoldi, Alberto

    2009-07-01

    Fibromyalgia (FM) is characterised by diffuse musculoskeletal pain and stiffness at multiple sites, tender points in characteristic locations, and the frequent presence of symptoms such as fatigue. The aim of this study was to assess whether the myoelectrical manifestations of fatigue in patients affected by FM are central or peripheral in origin. Eight female patients aged 55.6 +/- 13.6 years (FM group) and eight healthy female volunteers aged 50.3 +/- 9.3 years (MCG) were studied by means of non-invasive surface electromyography (s-EMG) involving a linear array of 16 electrodes placed on the skin overlying the biceps brachii muscle, with muscle fatigue being evoked by means of voluntary and involuntary (electrically elicited) contractions. Maximal voluntary contractions (MVCs), motor unit action potential conduction velocity distributions (mean +/- SD and skewness), and the mean power frequency of the spectrum (MNF) were estimated in order to assess whether there were any significant differences between the two groups and contraction types. The motor pattern of recruitment during voluntary contractions was altered in the FM patients, who also showed fewer myoelectrical manifestations of fatigue (normalised conduction velocity rate of changes: -0.074 +/- 0.052%/s in FM vs -0.196 +/- 0.133%/s in MCG; normalised MNF rate of changes: -0.29 +/- 0.16%/s in FM vs -0.66 +/- 0.34%/s in MCG). Mean conduction velocity distribution and skewnesses values were higher (p fatigue in FM is the electrophysiological expression of muscle remodelling in terms of the prevalence of slow conducting fatigue-resistant type I fibres. As the only between-group differences concerned voluntary contractions, they are probably more related to central motor control failure than muscle membrane alterations, which suggests pathological muscle fibre remodelling related to altered suprasegmental control.

  11. Real Time Implementation of a DC Motor Speed Control by Fuzzy Logic Controller and PI Controller Using FPGA

    Directory of Open Access Journals (Sweden)

    G. Sakthivel

    2010-10-01

    Full Text Available Fuzzy logic control has met with growing interest in many motor control applications due to its non-linearity, handling features and independence of plant modelling. The hardware implementation of fuzzy logic controller (FLC on FPGA is very important because of the increasing number of fuzzy applications requiring highly parallel and high speed fuzzy processing. Implementation of a fuzzy logic controller and conventional PI controller on an FPGA using VHDL for DC motor speed control is presented in this paper. The proposed scheme is to improve tracking performance of D.C. motor as compared to the conventional (PI control strategy .This paper describes the hardware implementation of two inputs (error and change in error, one output fuzzy logic controller based on PI controller and conventional PI controller using VHDL. Real time implementation FLC and conventional PI controller is made on Spartan-3A DSP FPGA (XC3SD1800A FPGA for the speed control of DC motor. It is observed that fuzzy logic based controllers give better responses than the conventional PI controller for the speed control of dc motor.

  12. PID Neural Network Based Speed Control of Asynchronous Motor Using Programmable Logic Controller

    Directory of Open Access Journals (Sweden)

    MARABA, V. A.

    2011-11-01

    Full Text Available This paper deals with the structure and characteristics of PID Neural Network controller for single input and single output systems. PID Neural Network is a new kind of controller that includes the advantages of artificial neural networks and classic PID controller. Functioning of this controller is based on the update of controller parameters according to the value extracted from system output pursuant to the rules of back propagation algorithm used in artificial neural networks. Parameters obtained from the application of PID Neural Network training algorithm on the speed model of the asynchronous motor exhibiting second order linear behavior were used in the real time speed control of the motor. Programmable logic controller (PLC was used as real time controller. The real time control results show that reference speed successfully maintained under various load conditions.

  13. Gait variability and motor control in people with knee osteoarthritis.

    Science.gov (United States)

    Alkjaer, Tine; Raffalt, Peter C; Dalsgaard, Helle; Simonsen, Erik B; Petersen, Nicolas C; Bliddal, Henning; Henriksen, Marius

    2015-10-01

    Knee osteoarthritis (OA) is a common disease that impairs walking ability and function. We compared the temporal gait variability and motor control in people with knee OA with healthy controls. The purpose was to test the hypothesis that the temporal gait variability would reflect a more stereotypic pattern in people with knee OA compared with healthy age-matched subjects. To assess the gait variability the temporal structure of the ankle and knee joint kinematics was quantified by the largest Lyapunov exponent and the stride time fluctuations were quantified by sample entropy and detrended fluctuation analysis. The motor control was assessed by the soleus (SO) Hoffmann (H)-reflex modulation and muscle co-activation during walking. The results showed no statistically significant mean group differences in any of the gait variability measures or muscle co-activation levels. The SO H-reflex amplitude was significantly higher in the knee OA group around heel strike when compared with the controls. The mean group difference in the H-reflex in the initial part of the stance phase (control-knee OA) was -6.6% Mmax (95% CI: -10.4 to -2.7, p=0.041). The present OA group reported relatively small impact of their disease. These results suggest that the OA group in general sustained a normal gait pattern with natural variability but with suggestions of facilitated SO H-reflex in the swing to stance phase transition. We speculate that the difference in SO H-reflex modulation reflects that the OA group increased the excitability of the soleus stretch reflex as a preparatory mechanism to avoid sudden collapse of the knee joint which is not uncommon in knee OA. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. A neuro-inspired spike-based PID motor controller for multi-motor robots with low cost FPGAs.

    Science.gov (United States)

    Jimenez-Fernandez, Angel; Jimenez-Moreno, Gabriel; Linares-Barranco, Alejandro; Dominguez-Morales, Manuel J; Paz-Vicente, Rafael; Civit-Balcells, Anton

    2012-01-01

    In this paper we present a neuro-inspired spike-based close-loop controller written in VHDL and implemented for FPGAs. This controller has been focused on controlling a DC motor speed, but only using spikes for information representation, processing and DC motor driving. It could be applied to other motors with proper driver adaptation. This controller architecture represents one of the latest layers in a Spiking Neural Network (SNN), which implements a bridge between robotics actuators and spike-based processing layers and sensors. The presented control system fuses actuation and sensors information as spikes streams, processing these spikes in hard real-time, implementing a massively parallel information processing system, through specialized spike-based circuits. This spike-based close-loop controller has been implemented into an AER platform, designed in our labs, that allows direct control of DC motors: the AER-Robot. Experimental results evidence the viability of the implementation of spike-based controllers, and hardware synthesis denotes low hardware requirements that allow replicating this controller in a high number of parallel controllers working together to allow a real-time robot control.

  15. A Neuro-Inspired Spike-Based PID Motor Controller for Multi-Motor Robots with Low Cost FPGAs

    Directory of Open Access Journals (Sweden)

    Anton Civit-Balcells

    2012-03-01

    Full Text Available In this paper we present a neuro-inspired spike-based close-loop controller written in VHDL and implemented for FPGAs. This controller has been focused on controlling a DC motor speed, but only using spikes for information representation, processing and DC motor driving. It could be applied to other motors with proper driver adaptation. This controller architecture represents one of the latest layers in a Spiking Neural Network (SNN, which implements a bridge between robotics actuators and spike-based processing layers and sensors. The presented control system fuses actuation and sensors information as spikes streams, processing these spikes in hard real-time, implementing a massively parallel information processing system, through specialized spike-based circuits. This spike-based close-loop controller has been implemented into an AER platform, designed in our labs, that allows direct control of DC motors: the AER-Robot. Experimental results evidence the viability of the implementation of spike-based controllers, and hardware synthesis denotes low hardware requirements that allow replicating this controller in a high number of parallel controllers working together to allow a real-time robot control.

  16. Upper motor neuron and extra-motor neuron involvement in amyotrophic lateral sclerosis: A clinical and brain imaging review

    NARCIS (Netherlands)

    van der Graaff, M. M.; de Jong, J. M. B. V.; Baas, F.; de Visser, M.

    2009-01-01

    There is an ongoing discussion whether ALS is primarily a disease of upper motor neurons or lower motor neurons. We undertook a review to assess how new insights have contributed to solve this controversy. For this purpose we selected relevant publications from 1995 onwards focussing on (1) primary

  17. 78 FR 20881 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards...

    Science.gov (United States)

    2013-04-08

    ...The EPA is announcing two public hearings to be held for the proposed rule ``Control of Air Pollution from Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards'' (the proposed rule is hereinafter referred to as ``Tier 3''), which will be published separately in the Federal Register. The hearings will be held in Philadelphia, PA on April 24, 2013 and in Chicago, IL on April 29, 2013. The comment period for the proposed rulemaking will end on June 13, 2013.

  18. Design and construction of stepper motor controller for brachy-therapy equipment

    International Nuclear Information System (INIS)

    Ahmad Rifai; Usep Setia Gunawan; Indarzah Masbatin Putra

    2011-01-01

    Based on a microcontroller, a stepper motor controller for brachy-therapy equipment has been designed and prototyped. The embedded control program routine and its other associated routines enable the microcontroller to generate required pulses via external commands for stepper motor based position control. The controller receives ASCII text command via a serial port. The constructed algorithm implements the widely used method that allows motor to rotate in three phases, i.e: acceleration, constant speed, and deceleration. (author)

  19. Development of EPICS based beam-line experimental control employing motor controller for precision positioning

    International Nuclear Information System (INIS)

    Tuli, Anupriya; Jain, Rajiv; Vora, H.S.

    2015-01-01

    In a Synchrotron Radiation Source the beamline experiments are carried out in radiation prone environment, inside the hutch, which demands to conduct experiments remotely. These experiments involves instrument control and data acquisition from various devices. Another factor which attributes to system complexity is precise positioning of sample and placement of detectors. A large number of stepper motors are engaged for achieving the required precision positioning. This work is a result of development of Experimental Physics and Industrial Control System (EPICS) based control system to interface a stepper motor controller developed indigenously by Laser Electronics Support Division of RRCAT. EPICS is an internationally accepted open source software environment which follows toolkit approach and standard model paradigm. The operator interface for the control system software was implemented using CSS BOY. The system was successfully tested for Ethernet based remote access. The developed control software comprises of an OPI and alarm handler (EPICS ALH). Both OPI and ALH are linked with PV's defined in database files. The development process resulted into a set of EPICS based commands for controlling stepper motor. These commands are independent of operator interface, i.e. stepper motor can be controlled by using these set of commands directly on EPICS prompt. This command set is illustrated in the above table. EPICS Alarm Handler was also tested independently by running these commands on EPIC prompt. If not using ALH, operator can read the alarm status of a PV using 'SEVR' and 'STAT' attributes. (author)

  20. Robust quasi NID current and flux control of an induction motor for position control

    NARCIS (Netherlands)

    van Duijnhoven, M.; Blachuta, M.J.

    1999-01-01

    In the paper, a new control design method called Dynamic Contraction method is applied to the flux and quadrature current robust control of an induction motor operated using the field orientation principle. The resulting input-output decoupled and linearized drive is then used for time-optimal

  1. Low-Cost Undergraduate Control Systems Experiments Using Microcontroller-Based Control of a DC Motor

    Science.gov (United States)

    Gunasekaran, M.; Potluri, R.

    2012-01-01

    This paper presents low-cost experiments for a control systems laboratory module that is worth one and a third credits. The experiments are organized around the microcontroller-based control of a permanent magnet dc motor. The experimental setups were built in-house. Except for the operating system, the software used is primarily freeware or free…

  2. Voltage directive drive with claw pole motor and control without rotor position indicator

    Science.gov (United States)

    Stroenisch, Volker Ewald

    Design and testing of a voltage directive drive for synchronous variable speed claw pole motor and control without rotor position indicator is described. Economic analysis of the designed regulation is performed. Computations of stationary and dynamic behavior are given and experimental operational behavior is determined. The motors can be used for electric transportation vehicles, diesel motors, and electric railway engines.

  3. Neuromolecular Imaging Shows Temporal Synchrony Patterns between Serotonin and Movement within Neuronal Motor Circuits in the Brain

    Directory of Open Access Journals (Sweden)

    Patricia A. Broderick

    2013-06-01

    Full Text Available The present discourse links the electrical and chemical properties of the brain with neurotransmitters and movement behaviors to further elucidate strategies to diagnose and treat brain disease. Neuromolecular imaging (NMI, based on electrochemical principles, is used to detect serotonin in nerve terminals (dorsal and ventral striata and somatodendrites (ventral tegmentum of reward/motor mesocorticolimbic and nigrostriatal brain circuits. Neuronal release of serotonin is detected at the same time and in the same animal, freely moving and unrestrained, while open-field behaviors are monitored via infrared photobeams. The purpose is to emphasize the unique ability of NMI and the BRODERICK PROBE® biosensors to empirically image a pattern of temporal synchrony, previously reported, for example, in Aplysia using central pattern generators (CPGs, serotonin and cerebral peptide-2. Temporal synchrony is reviewed within the context of the literature on central pattern generators, neurotransmitters and movement disorders. Specifically, temporal synchrony data are derived from studies on psychostimulant behavior with and without cocaine while at the same time and continuously, serotonin release in motor neurons within basal ganglia, is detected. The results show that temporal synchrony between the neurotransmitter, serotonin and natural movement occurs when the brain is NOT injured via, e.g., trauma, addictive drugs or psychiatric illness. In striking contrast, in the case of serotonin and cocaine-induced psychostimulant behavior, a different form of synchrony and also asynchrony can occur. Thus, the known dysfunctional movement behavior produced by cocaine may well be related to the loss of temporal synchrony, the loss of the ability to match serotonin in brain with motor activity. The empirical study of temporal synchrony patterns in humans and animals may be more relevant to the dynamics of motor circuits and movement behaviors than are studies of

  4. Neuromolecular Imaging Shows Temporal Synchrony Patterns between Serotonin and Movement within Neuronal Motor Circuits in the Brain.

    Science.gov (United States)

    Broderick, Patricia A

    2013-06-21

    The present discourse links the electrical and chemical properties of the brain with neurotransmitters and movement behaviors to further elucidate strategies to diagnose and treat brain disease. Neuromolecular imaging (NMI), based on electrochemical principles, is used to detect serotonin in nerve terminals (dorsal and ventral striata) and somatodendrites (ventral tegmentum) of reward/motor mesocorticolimbic and nigrostriatal brain circuits. Neuronal release of serotonin is detected at the same time and in the same animal, freely moving and unrestrained, while open-field behaviors are monitored via infrared photobeams. The purpose is to emphasize the unique ability of NMI and the BRODERICK PROBE® biosensors to empirically image a pattern of temporal synchrony, previously reported, for example, in Aplysia using central pattern generators (CPGs), serotonin and cerebral peptide-2. Temporal synchrony is reviewed within the context of the literature on central pattern generators, neurotransmitters and movement disorders. Specifically, temporal synchrony data are derived from studies on psychostimulant behavior with and without cocaine while at the same time and continuously, serotonin release in motor neurons within basal ganglia, is detected. The results show that temporal synchrony between the neurotransmitter, serotonin and natural movement occurs when the brain is NOT injured via, e.g., trauma, addictive drugs or psychiatric illness. In striking contrast, in the case of serotonin and cocaine-induced psychostimulant behavior, a different form of synchrony and also asynchrony can occur. Thus, the known dysfunctional movement behavior produced by cocaine may well be related to the loss of temporal synchrony, the loss of the ability to match serotonin in brain with motor activity. The empirical study of temporal synchrony patterns in humans and animals may be more relevant to the dynamics of motor circuits and movement behaviors than are studies of static parameters

  5. Design of linear pulse motor for control element drive mechanism of SMART

    International Nuclear Information System (INIS)

    Kim, J. H.; Huh, H.; Kim, J. I.; Jang, M. H.; Kang, D. H.

    1999-01-01

    49 Control Rod Drive Mechanisms(CEDMs) are densely installed on the reactor central head of SMART. The structural design should ensure the space for maintenance/repair, cable routing, and heat release from the motor. In this paper, an improved design is presented to enlarge the space between CEDMs by decreasing the diameter of linear pulse motor. The reduction of motor thrust force due to the decrease of the motor diameter is compensated by resizing the other structural components

  6. Relationship Between Non-invasive Brain Stimulation-induced Plasticity and Capacity for Motor Learning.

    Science.gov (United States)

    López-Alonso, Virginia; Cheeran, Binith; Fernández-del-Olmo, Miguel

    2015-01-01

    Cortical plasticity plays a key role in motor learning (ML). Non-invasive brain stimulation (NIBS) paradigms have been used to modulate plasticity in the human motor cortex in order to facilitate ML. However, little is known about the relationship between NIBS-induced plasticity over M1 and ML capacity. NIBS-induced MEP changes are related to ML capacity. 56 subjects participated in three NIBS (paired associative stimulation, anodal transcranial direct current stimulation and intermittent theta-burst stimulation), and in three lab-based ML task (serial reaction time, visuomotor adaptation and sequential visual isometric pinch task) sessions. After clustering the patterns of response to the different NIBS protocols, we compared the ML variables between the different patterns found. We used regression analysis to explore further the relationship between ML capacity and summary measures of the MEPs change. We ran correlations with the "responders" group only. We found no differences in ML variables between clusters. Greater response to NIBS protocols may be predictive of poor performance within certain blocks of the VAT. "Responders" to AtDCS and to iTBS showed significantly faster reaction times than "non-responders." However, the physiological significance of these results is uncertain. MEP changes induced in M1 by PAS, AtDCS and iTBS appear to have little, if any, association with the ML capacity tested with the SRTT, the VAT and the SVIPT. However, cortical excitability changes induced in M1 by AtDCS and iTBS may be related to reaction time and retention of newly acquired skills in certain motor learning tasks. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Hitting the right target : noninvasive localization of the subthalamic nucleus motor part for specific deep brain stimulation

    NARCIS (Netherlands)

    Brunenberg, E.J.L.

    2011-01-01

    Deep brain stimulation of the subthalamic nucleus (STN) has gained momentum as a therapy for advanced Parkinson’s disease. The stimulation effectively alleviates the patients’ typical motor symptoms on a long term, but can give rise to cognitive and psychiatric adverse effects as well. Based on

  8. Interaction of attentional and motor control processes in handwriting.

    Science.gov (United States)

    Brown, T L; Donnenwirth, E E

    1990-01-01

    The interaction between attentional capacity, motor control processes, and strategic adaptations to changing task demands was investigated in handwriting, a continuous (rather than discrete) skilled performance. Twenty-four subjects completed 12 two-minute handwriting samples under instructions stressing speeded handwriting, normal handwriting, or highly legible handwriting. For half of the writing samples, a concurrent auditory monitoring task was imposed. Subjects copied either familiar (English) or unfamiliar (Latin) passages. Writing speed, legibility ratings, errors in writing and in the secondary auditory task, and a derived measure of the average number of characters held in short-term memory during each sample ("planning unit size") were the dependent variables. The results indicated that the ability to adapt to instructions stressing speed or legibility was substantially constrained by the concurrent listening task and by text familiarity. Interactions between instructions, task concurrence, and text familiarity in the legibility ratings, combined with further analyses of planning unit size, indicated that information throughput from temporary storage mechanisms to motor processes mediated the loss of flexibility effect. Overall, the results suggest that strategic adaptations of a skilled performance to changing task circumstances are sensitive to concurrent attentional demands and that departures from "normal" or "modal" performance require attention.

  9. Proposed torque optimized behavior for digital speed control of induction motors

    Energy Technology Data Exchange (ETDEWEB)

    Metwally, H.M.B.; El-Shewy, H.M.; El-Kholy, M.M. [Zagazig Univ., Dept. of Electrical Engineering, Zagazig (Egypt); Abdel-Kader, F.E. [Menoufyia Univ., Dept. of Electrical Engineering, Menoufyia (Egypt)

    2002-09-01

    In this paper, a control strategy for speed control of induction motors with field orientation is proposed. The proposed method adjusts the output voltage and frequency of the converter to operate the motor at the desired speed with maximum torque per ampere at all load torques keeping the torque angle equal to 90 deg. A comparison between the performance characteristics of a 2 hp induction motor using three methods of speed control is presented. These methods are the proposed method, the direct torque control method and the constant V/f method. The comparison showed that better performance characteristics are obtained using the proposed speed control strategy. A computer program, based on this method, is developed. Starting from the motor parameters, the program calculates a data set for the stator voltage and frequency required to obtain maximum torque per ampere at any motor speed and load torque. This data set can be used by the digital speed control system of induction motors. (Author)

  10. Fetal frontal cortex transplant (14C) 2-deoxyglucose uptake and histology: survival in cavities of host rat brain motor cortex

    International Nuclear Information System (INIS)

    Sharp, F.R.; Gonzalez, M.F.

    1984-01-01

    Fetal frontal neocortex from 18-day-old rat embryonic brain was transplanted into cavities in 30-day-old host motor cortex. Sixty days after transplantation, 5 of 15 transplanted rats had surviving fetal transplants. The fetal cortex transplants were physically attached to the host brain, completely filled the original cavity, and had numerous surviving cells including pyramidal neurons. Cell lamination within the fetal transplant was abnormal. The ( 14 C) 2-deoxyglucose uptake of all five of the fetal neocortex transplants was less than adjacent cortex and contralateral host motor-sensory cortex, but more than adjacent corpus callosum white matter. The results indicate that fetal frontal neocortex can be transplanted into damaged rat motor cortex. The metabolic rate of the transplants suggests they could be partially functional

  11. Research and simulation of the decoupling transformation in AC motor vector control

    Science.gov (United States)

    He, Jiaojiao; Zhao, Zhongjie; Liu, Ken; Zhang, Yongping; Yao, Tuozhong

    2018-04-01

    Permanent magnet synchronous motor (PMSM) is a nonlinear, strong coupling, multivariable complex object, and transformation decoupling can solve the coupling problem of permanent magnet synchronous motor. This paper gives a permanent magnet synchronous motor (PMSM) mathematical model, introduces the permanent magnet synchronous motor vector control coordinate transformation in the process of modal matrix inductance matrix transform through the matrix related knowledge of different coordinates of diagonalization, which makes the coupling between the independent, realize the control of motor current and excitation the torque current coupling separation, and derived the coordinate transformation matrix, the thought to solve the coupling problem of AC motor. Finally, in the Matlab/Simulink environment, through the establishment and combination between the PMSM ontology, coordinate conversion module, built the simulation model of permanent magnet synchronous motor vector control, introduces the model of each part, and analyzed the simulation results.

  12. Motor abundance and control structure in the golf swing.

    Science.gov (United States)

    Morrison, A; McGrath, D; Wallace, E S

    2016-04-01

    Variability and control structure are under-represented areas of golf swing research. This study investigated the use of the abundant degrees of freedom in the golf swing of high and intermediate skilled golfers using uncontrolled manifold (UCM) analysis. The variance parallel to (VUCM) and orthogonal to (VOrth) the UCM with respect to the orientation and location of the clubhead were calculated. The higher skilled golfers had proportionally higher values of VUCM than lower skilled players for all measured outcome variables. Motor synergy was found in the control of the orientation of the clubhead and the combined outcome variables but not for clubhead location. Clubhead location variance zeroed-in on impact as has been previously shown, whereas clubhead orientation variance increased near impact. Both skill levels increased their control over the clubhead location leading up to impact, with more control exerted over the clubhead orientation in the early downswing. The results suggest that to achieve higher skill levels in golf may not lie simply in optimal technique, but may lie more in developing control over the abundant degrees of freedom in the body. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. A discreet control of sliding ways of an induction motor; Control discreto de modos deslizantes de un motor de induccion

    Energy Technology Data Exchange (ETDEWEB)

    Rivera Dominguez, Jorge

    2001-12-15

    A control of sliding ways in discreet time for non-linear discreet systems is designed, also the technique of the control by histograms for non-linear discreet systems was developed, and an observer of reduced order was developed for non-linear electromechanical discreet systems. All these techniques are applied to a non-linear discreet model of an induction motor that was found here, that posses electrical and mechanical dynamics, in which the load pair is considered an unknown disturbance. With complete measurements of the states are satisfied the pursuing of the rotor velocity and the amplitude of the magnetic flux of the rotor, where the unknown load does not affect the velocity regulation. Next, an observer of reduced order is implemented where the velocity and current measurements are employed to consider the load pair and the flows that are very difficult to measure. The proposed method has a design and stability procedure of direct analyses, conserving a simple structure of the control law. The simulations predict that the system is robust with respect to several types of load pairs. The responses of velocity and amplitude of the rotor flow and the entrance references evolved very well. These references have a linear dynamics of second order with time constants that can be chosen by the motor user. The practical aspects for a future digital implementation of the control law are considered, including the velocity and currents sensors, the preparation of signals, the transformation of the current in the frame of stationary reference, PWM and inverter modules, which were seen in detail. The experimental results are left as a future work. [Spanish] Se disena un control de modos deslizantes en tiempo discreto para sistemas discretos no lineales, tambien se desarrollo la tecnica del control por bloques para sistemas discretos no lineales, y un observador de orden reducido fue desarrollado para sistemas discretos electromecanicos no lineales. Todas estas tecnicas

  14. Position Control of Linear Synchronous Motor Drives with Exploitation of Forced Dynamics Control Principles

    Directory of Open Access Journals (Sweden)

    Jan Vittek

    2004-01-01

    Full Text Available Closed-loop position control of mechanisms directly driven by linear synchronous motors with permanent magnets is presented. The control strategy is based on forced dynamic control, which is a form of feedback linearisation, yielding a non-liner multivariable control law to obtain a prescribed linear speed dynamics together with the vector control condition of mutal orthogonality between the stator current and magnetic flux vectors (assuming perfect estimates of the plant parameters. Outer position control loop is closed via simple feedback with proportional gain. Simulations of the design control sysstem, including the drive with power electronic switching, predict the intended drive performance.

  15. Intelligent robust control law for induction motors based on field-oriented control theory

    Energy Technology Data Exchange (ETDEWEB)

    Barambones, O.; Alcorta, P.; Sevillano, G.; Garrido, A.; Garrido, I. [Univ. del Pais Vasco, Bilbao (Spain). Dpto. Ingenieri a de Sistemas y Automatica

    2009-07-01

    A sensorless adaptive control law was developed to improve the trajectory tracking performance of induction motors. The law used an integral sliding mode algorithm to avoid the necessity of calculating an upper bound for system uncertainties. The vector control theory was used to develop the induction motor drives. The sliding mode control law incorporated an adaptive switching gain and included a method of estimating rotor speeds. Rotor speed estimation errors were presented as a first order simple function based on the difference between real stator currents and estimated stator currents. The Lyapunov stability theory was used to analyze the controller under different load disturbances and parameter uncertainties. Results of the study showed that the control signal of the scheme was smaller than signals obtained using traditional variable structure control schemes. It was concluded that speed tracking objectives can be obtained under various parameter and torque uncertainties. 9 refs., 7 figs.

  16. Review of Apraxia: The cognitive side of motor control

    DEFF Research Database (Denmark)

    Martínez-Ferreiro, Silvia

    2014-01-01

    Reviews the book, Apraxia: The Cognitive Side of Motor Control by G. Goldenberg (see record 2013-31133-000). The book makes a significant contribution to the study of this multifaceted syndrome, especially in relation to limb apraxia, the author’s main research area. Despite more than 100 years...... of tradition in the field, this book is the first comprehensive account of its history, philosophy and experimental research. Consequently, this volume fulfils both the author’s main aim to assemble a comprehensive review of cases, considerations and theories about apraxia, and fills in an already too long...... the original texts. Part II concerns the survey of contemporary empirical evidence and its impact on the diverse theories available for apraxia. The book concludes with the author’s own view on apraxia and a word on therapy. On the whole, the book provides the reader with deep insights into the evolution...

  17. Stepping motor control processor reference manual. Volume I

    International Nuclear Information System (INIS)

    Holloway, F.W.; VanArsdall, P.J.; Suski, G.J.; Gant, R.G.; Rash, M.

    1980-01-01

    This manual is intended to serve several purposes. The first goal is to describe the capabilities and operation of the SMC processor package from an operator or user point of view. Secondly, the manual will describe in some detail the basic hardware elements and how they can be used effectively to implement a step motor control system. Practical information on the use, installation and checkout of the hardware set is presented in the following sections along with programming suggestions. Available related system software is described in this manual for reference and as an aid in understanding the system architecture. Section two presents an overview and operations manual of the SMC processor describing its composition and functional capabilities. Section three contains hardware descriptions in some detail for the LLL-designed hardware used in the SMC processor. Basic theory of operation and important features are explained

  18. Feed-forward motor control of ultrafast, ballistic movements.

    Science.gov (United States)

    Kagaya, K; Patek, S N

    2016-02-01

    To circumvent the limits of muscle, ultrafast movements achieve high power through the use of springs and latches. The time scale of these movements is too short for control through typical neuromuscular mechanisms, thus ultrafast movements are either invariant or controlled prior to movement. We tested whether mantis shrimp (Stomatopoda: Neogonodactylus bredini) vary their ultrafast smashing strikes and, if so, how this control is achieved prior to movement. We collected high-speed images of strike mechanics and electromyograms of the extensor and flexor muscles that control spring compression and latch release. During spring compression, lateral extensor and flexor units were co-activated. The strike initiated several milliseconds after the flexor units ceased, suggesting that flexor activity prevents spring release and determines the timing of strike initiation. We used linear mixed models and Akaike's information criterion to serially evaluate multiple hypotheses for control mechanisms. We found that variation in spring compression and strike angular velocity were statistically explained by spike activity of the extensor muscle. The results show that mantis shrimp can generate kinematically variable strikes and that their kinematics can be changed through adjustments to motor activity prior to the movement, thus supporting an upstream, central-nervous-system-based control of ultrafast movement. Based on these and other findings, we present a shishiodoshi model that illustrates alternative models of control in biological ballistic systems. The discovery of feed-forward control in mantis shrimp sets the stage for the assessment of targets, strategic variation in kinematics and the role of learning in ultrafast animals. © 2016. Published by The Company of Biologists Ltd.

  19. Deep Brain Stimulation for Parkinson's Disease with Early Motor Complications: A UK Cost-Effectiveness Analysis.

    Directory of Open Access Journals (Sweden)

    Tomasz Fundament

    Full Text Available Parkinson's disease (PD is a debilitating illness associated with considerable impairment of quality of life and substantial costs to health care systems. Deep brain stimulation (DBS is an established surgical treatment option for some patients with advanced PD. The EARLYSTIM trial has recently demonstrated its clinical benefit also in patients with early motor complications. We sought to evaluate the cost-effectiveness of DBS, compared to best medical therapy (BMT, among PD patients with early onset of motor complications, from a United Kingdom (UK payer perspective.We developed a Markov model to represent the progression of PD as rated using the Unified Parkinson's Disease Rating Scale (UPDRS over time in patients with early PD. Evidence sources were a systematic review of clinical evidence; data from the EARLYSTIM study; and a UK Clinical Practice Research Datalink (CPRD dataset including DBS patients. A mapping algorithm was developed to generate utility values based on UPDRS data for each intervention. The cost-effectiveness was expressed as the incremental cost per quality-adjusted life-year (QALY. One-way and probabilistic sensitivity analyses were undertaken to explore the effect of parameter uncertainty.Over a 15-year time horizon, DBS was predicted to lead to additional mean cost per patient of £26,799 compared with BMT (£73,077/patient versus £46,278/patient and an additional mean 1.35 QALYs (6.69 QALYs versus 5.35 QALYs, resulting in an incremental cost-effectiveness ratio of £19,887 per QALY gained with a 99% probability of DBS being cost-effective at a threshold of £30,000/QALY. One-way sensitivity analyses suggested that the results were not significantly impacted by plausible changes in the input parameter values.These results indicate that DBS is a cost-effective intervention in PD patients with early motor complications when compared with existing interventions, offering additional health benefits at acceptable incremental

  20. Large-Scale Assessment of a Fully Automatic Co-Adaptive Motor Imagery-Based Brain Computer Interface.

    Directory of Open Access Journals (Sweden)

    Laura Acqualagna

    Full Text Available In the last years Brain Computer Interface (BCI technology has benefited from the development of sophisticated machine leaning methods that let the user operate the BCI after a few trials of calibration. One remarkable example is the recent development of co-adaptive techniques that proved to extend the use of BCIs also to people not able to achieve successful control with the standard BCI procedure. Especially for BCIs based on the modulation of the Sensorimotor Rhythm (SMR these improvements are essential, since a not negligible percentage of users is unable to operate SMR-BCIs efficiently. In this study we evaluated for the first time a fully automatic co-adaptive BCI system on a large scale. A pool of 168 participants naive to BCIs operated the co-adaptive SMR-BCI in one single session. Different psychological interventions were performed prior the BCI session in order to investigate how motor coordination training and relaxation could influence BCI performance. A neurophysiological indicator based on the Power Spectral Density (PSD was extracted by the recording of few minutes of resting state brain activity and tested as predictor of BCI performances. Results show that high accuracies in operating the BCI could be reached by the majority of the participants before the end of the session. BCI performances could be significantly predicted by the neurophysiological indicator, consolidating the validity of the model previously developed. Anyway, we still found about 22% of users with performance significantly lower than the threshold of efficient BCI control at the end of the session. Being the inter-subject variability still the major problem of BCI technology, we pointed out crucial issues for those who did not achieve sufficient control. Finally, we propose valid developments to move a step forward to the applicability of the promising co-adaptive methods.

  1. Speed control of switched reluctance motor using sliding mode control strategy

    Energy Technology Data Exchange (ETDEWEB)

    John, G. [Kenetech Windpower, Livermore, CA (United States); Eastham, A.R. [Queen`s Univ., Kingston, Ontario (Canada). Dept. of Electrical Engineering

    1995-12-31

    A robust speed drive system for a switched reluctance motor (SRM) using sliding mode control strategy (SLMC) is presented. After reviewing the operation of an SRM drive, a SLMC based scheme is formulated to control the drive speed. The scheme is implemented using a micro-controller and a high resolution position sensor. The parameter insensitive characteristics are demonstrated through computer simulations and experimental verification.

  2. Research on Control System of Three - phase Brushless DC Motor for Electric Vehicle

    Science.gov (United States)

    Wang, Zhiwei; Jin, Hai; Guo, Jie; Su, Jie; Wang, Miao

    2017-12-01

    In order to study the three-phase brushless motor control system of electric vehicle, Freescale9S12XS128 chip is used as the control core, and the power MOSFET is used as the inverter device. The software is compiled by Codewarrior software. The speed control link adopts open-loop control, and the control chip collects the external sensor signal voltage Change control PWM signal output control three-phase brushless DC motor speed. The whole system consists of Hall position detection module, current detection module, power drive module and voltage detection module. The basic functions of three-phase brushless DC motor drive control are realized.

  3. Solid state circuit controls direction, speed, and braking of dc motor

    Science.gov (United States)

    Hanna, M. F.

    1966-01-01

    Full-wave bridge rectifier circuit controls the direction, speed, and braking of a dc motor. Gating in the circuit of Silicon Controlled Rectifiers /SCRS/ controls output polarity and braking is provided by an SCR that is gated to short circuit the reverse voltage generated by reversal of motor rotation.

  4. Simple Power Control for Sensorless Induction Motor Drives Fed by a Matrix Converter

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Lee, Kyo Beum

    2008-01-01

    This paper presents a new and simple method for sensorless control of matrix converter drives using a power flowing to the motor. The proposed control algorithm is based on controlling the instantaneous real and imaginary powers into the induction motor. To improve low-speed sensorless performance...

  5. Application of drive circuit based on L298N in direct current motor speed control system

    Science.gov (United States)

    Yin, Liuliu; Wang, Fang; Han, Sen; Li, Yuchen; Sun, Hao; Lu, Qingjie; Yang, Cheng; Wang, Quanzhao

    2016-10-01

    In the experiment of researching the nanometer laser interferometer, our design of laser interferometer circuit system is up to the wireless communication technique of the 802.15.4 IEEE standard, and we use the RF TI provided by Basic to receive the data on speed control system software. The system's hardware is connected with control module and the DC motor. However, in the experiment, we found that single chip microcomputer control module is very difficult to drive the DC motor directly. The reason is that the DC motor's starting and braking current is larger than the causing current of the single chip microcomputer control module. In order to solve this problem, we add a driving module that control board can transmit PWM wave signal through I/O port to drive the DC motor, the driving circuit board can come true the function of the DC motor's positive and reversal rotation and speed adjustment. In many various driving module, the L298N module's integrated level is higher compared with other driver module. The L298N model is easy to control, it not only can control the DC motor, but also achieve motor speed control by modulating PWM wave that the control panel output. It also has the over-current protection function, when the motor lock, the L298N model can protect circuit and motor. So we use the driver module based on L298N to drive the DC motor. It is concluded that the L298N driver circuit module plays a very important role in the process of driving the DC motor in the DC motor speed control system.

  6. Motor outcome and electrode location in deep brain stimulation in Parkinson's disease.

    Science.gov (United States)

    Koivu, Maija; Huotarinen, Antti; Scheperjans, Filip; Laakso, Aki; Kivisaari, Riku; Pekkonen, Eero

    2018-05-30

    To evaluate the efficacy and adverse effects of subthalamic deep brain stimulation (STN-DBS) in patients with advanced Parkinson's disease (PD) and the possible correlation between electrode location and clinical outcome. We retrospectively reviewed 87 PD-related STN-DBS operations at Helsinki University Hospital (HUH) from 2007 to 2014. The changes of Unified Parkinson's Disease Rating Scale (UPDRS) part III score, Hoehn & Yahr stage, antiparkinson medication, and adverse effects were studied. We estimated the active electrode location in three different coordinate systems: direct visual analysis of MRI correlated to brain atlas, location in relation to the nucleus borders and location in relation to the midcommisural point. At 6 months after operation, both levodopa equivalent doses (LEDs; 35%, Wilcoxon signed-rank test = 0.000) and UPDRS part III scores significantly decreased (38%, Wilcoxon signed-rank test = 0.000). Four patients (5%) suffered from moderate DBS-related dysarthria. The generator and electrodes had to be removed in one patient due to infection (1%). Electrode coordinates in the three coordinate systems correlated well with each other. On the left side, more ventral location of the active contact was associated with greater LED decrease. STN-DBS improves motor function and enables the reduction in antiparkinson medication with an acceptable adverse effect profile. More ventral location of the active contact may allow stronger LED reduction. Further research on the correlation between contact location, clinical outcome, and LED reduction is warranted. © 2018 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.

  7. Functional magnetic resonance imaging-controlled neuronavigator-guided brain surgery: a case report.

    Science.gov (United States)

    Morioka, J; Nishizaki, T; Tokumaru, T; Uesugi, S; Yamashita, K; Ito, H; Suzuki, M

    2001-05-01

    The effectiveness of functional magnetic resonance imaging (f-MRI)-controlled and navigator-guided brain surgery for a patient with a recurrent astrocytoma is demonstrated. Preoperative f-MRI was performed in order to identify the motor area and ensure that the tumour was in the left prefrontal area. A more aggressive operation was planned for the recurrent tumour. The f-MRI data were input to the MKM navigation system and during the operation the contours of the tumour and motor area were visualised b y the microscope of the navigation system. The tumour and surrounding gliotic brain tissue were removed completely. The diagnosis was a grade III astrocytoma. The combination of the navigation system and f-MRI was useful for preoperative design of the surgical strategy, and tumour orientation during the operation, enabling aggressive surgery to be performed without functional deficits ensuing. Copyright 2001 Harcourt Publishers Ltd.

  8. Emotional Learning Based Intelligent Controllers for Rotor Flux Oriented Control of Induction Motor

    Science.gov (United States)

    Abdollahi, Rohollah; Farhangi, Reza; Yarahmadi, Ali

    2014-08-01

    This paper presents design and evaluation of a novel approach based on emotional learning to improve the speed control system of rotor flux oriented control of induction motor. The controller includes a neuro-fuzzy system with speed error and its derivative as inputs. A fuzzy critic evaluates the present situation, and provides the emotional signal (stress). The controller modifies its characteristics so that the critics stress is reduced. The comparative simulation results show that the proposed controller is more robust and hence found to be a suitable replacement of the conventional PI controller for the high performance industrial drive applications.

  9. Brain mechanisms that control sleep and waking

    Science.gov (United States)

    Siegel, Jerome

    This review paper presents a brief historical survey of the technological and early research that laid the groundwork for recent advances in sleep-waking research. A major advance in this field occurred shortly after the end of World War II with the discovery of the ascending reticular activating system (ARAS) as the neural source in the brain stem of the waking state. Subsequent research showed that the brain stem activating system produced cortical arousal via two pathways: a dorsal route through the thalamus and a ventral route through the hypothalamus and basal forebrain. The nuclei, pathways, and neurotransmitters that comprise the multiple components of these arousal systems are described. Sleep is now recognized as being composed of two very different states: rapid eye movements (REMs) sleep and non-REM sleep. The major findings on the neural mechanisms that control these two sleep states are presented. This review ends with a discussion of two current views on the function of sleep: to maintain the integrity of the immune system and to enhance memory consolidation.

  10. Fine Motor Control Is Related to Cognitive Control in Adolescents with Down Syndrome

    Science.gov (United States)

    Chen, Chih-Chia; Ringenbach, Shannon D. R.; Albert, Andrew; Semken, Keith

    2014-01-01

    The connection between human cognitive development and motor functioning has been systematically examined in many typical and atypical populations; however, only a few studies focus on people with Down syndrome (DS). Twelve adolescents with DS participated and their cognitive control, measured by the Corsi-Block tapping test (e.g., visual working…

  11. Performance analysis of PM synchronous motor using fuzzy logic and self tuning fuzzy PI speed controls

    International Nuclear Information System (INIS)

    Karakaya, A.; Karakas, E.

    2008-01-01

    Permanent Magnet Synchronous Motors have nonlinear characteristics whose dynamics changes with time. In spite of this structure the permanent magnet synchronous motor has answered engineering problems in industry such as motion control which need high torque values. This paper obtains a nonlinear mathematical model for Permanent Magnet Synchronous Motor and realizes stimulation of the obtained model in the Matlab/Simulink program. Motor parameters are determined by an experimental set-up and they are used in the motor model. Speed control of motor model is made with Fuzzy Logic and Self Tuning logic PI controllers. Using the speed graphs obtained, rise time, overshoot, steady-state error and settling time are analyzed and controller performances are compared. (author)

  12. Excited state dynamics & optical control of molecular motors

    Science.gov (United States)

    Wiley, Ted; Sension, Roseanne

    2014-03-01

    Chiral overcrowded alkenes are likely candidates for light driven rotary molecular motors. At their core, these molecular motors are based on the chromophore stilbene, undergoing ultrafast cis/trans photoisomerization about their central double bond. Unlike stilbene, the photochemistry of molecular motors proceeds in one direction only. This unidirectional rotation is a result of helicity in the molecule induced by steric hindrance. However, the steric hindrance which ensures unidirectional excited state rotation, has the unfortunate consequence of producing large ground state barriers which dramatically decrease the overall rate of rotation. These molecular scale ultrafast motors have only recently been studied by ultrafast spectroscopy. Our lab has studied the photochemistry and photophysics of a ``first generation'' molecular motor with UV-visible transient absorption spectroscopy. We hope to use optical pulse shaping to enhance the efficiency and turnover rate of these molecular motors.

  13. Losses in chopper-controlled DC series motors

    Science.gov (United States)

    Hamilton, H. B.

    1982-01-01

    Motors for electric vehicle (EV) applications must have different features than dc motors designed for industrial applications. The EV motor application is characterized by the following requirements: (1) the need for highest possible efficiency from light load to overload, for maximum EV range, (2) large short time overload capability (The ratio of peak to average power varies from 5/1 in heavy city traffic to 3/1 in suburban driving situations) and (3) operation from power supply voltage levels of 84 to 144 volts (probably 120 volts maximum). A test facility utilizing a dc generator as a substitute for a battery pack was designed and utilized. Criteria for the design of such a facility are presented. Two motors, differing in design detail, commercially available for EV use were tested. Losses measured are discussed, as are waves forms and their harmonic content, the measurements of resistance and inductance, EV motor/chopper application criteria, and motor design considerations.

  14. Speed response of brushless DC motor using fuzzy PID controller under varying load condition

    Directory of Open Access Journals (Sweden)

    Akash Varshney

    2017-09-01

    Full Text Available The increasing trend towards usage of precisely controlled, high torque, efficient and low noise motors for dedicated applications has attracted the attention of researcher in Brushless DC (BLDC motors. BLDC motors can act as an acceptable alternative to the conventional motors like Induction Motors, Switched Reluctance Motors etc. This paper presents a detailed study on the performance of a BLDC motor supplying different types of loads, and at the same time, deploying different control techniques. An advance Fuzzy PID controller is compared with the commonly used PID controller. The load variations considered are of the most common types, generally encountered in practice. A comparison has been carried out in this paper by observing the dynamic speed response of motor at the time of application as well as at the time of removal of the load. The BLDC motors suffer from a major drawback of having jerky behaviour at the time of load removal. The study reveals that irrespective of the type of controller used, the gradual load variation produces better results as against sudden load variations. It is further observed that in addition to other dynamic features, the jerks produced at the time of load removal also get improved to a large extent with Fuzzy PID controller.The speed torque characteristics unraveled the fact that the jerks are minimum at the time of gradual load removal with Fuzzy PID controller in place. An attempt has been made to define these jerks by ‘Perturbation Window’.

  15. Ephrin-B3 is the midline barrier that prevents corticospinal tract axons from recrossing, allowing for unilateral motor control.

    Science.gov (United States)

    Kullander, K; Croll, S D; Zimmer, M; Pan, L; McClain, J; Hughes, V; Zabski, S; DeChiara, T M; Klein, R; Yancopoulos, G D; Gale, N W

    2001-04-01

    Growing axons follow highly stereotypical pathways, guided by a variety of attractive and repulsive cues, before establishing specific connections with distant targets. A particularly well-known example that illustrates the complexity of axonal migration pathways involves the axonal projections of motor neurons located in the motor cortex. These projections take a complex route during which they first cross the midline, then form the corticospinal tract, and ultimately connect with motor neurons in the contralateral side of the spinal cord. These obligatory contralateral connections account for why one side of the brain controls movement on the opposing side of the body. The netrins and slits provide well-known midline signals that regulate axonal crossings at the midline. Herein we report that a member of the ephrin family, ephrin-B3, also plays a key role at the midline to regulate axonal crossing. In particular, we show that ephrin-B3 acts as the midline barrier that prevents corticospinal tract projections from recrossing when they enter the spinal gray matter. We report that in ephrin-B3(-/-) mice, corticospinal tract projections freely recross in the spinal gray matter, such that the motor cortex on one side of the brain now provides bilateral input to the spinal cord. This neuroanatomical abnormality in ephrin-B3(-/-) mice correlates with loss of unilateral motor control, yielding mice that simultaneously move their right and left limbs and thus have a peculiar hopping gait quite unlike the alternate step gait displayed by normal mice. The corticospinal and walking defects in ephrin-B3(-/-) mice resemble those recently reported for mice lacking the EphA4 receptor, which binds ephrin-B3 as well as other ephrins, suggesting that the binding of EphA4-bearing axonal processes to ephrin-B3 at the midline provides the repulsive signal that prevents corticospinal tract projections from recrossing the midline in the developing spinal cord.

  16. Goal selection versus process control in a brain-computer interface based on sensorimotor rhythms.

    Science.gov (United States)

    Royer, Audrey S; He, Bin

    2009-02-01

    In a brain-computer interface (BCI) utilizing a process control strategy, the signal from the cortex is used to control the fine motor details normally handled by other parts of the brain. In a BCI utilizing a goal selection strategy, the signal from the cortex is used to determine the overall end goal of the user, and the BCI controls the fine motor details. A BCI based on goal selection may be an easier and more natural system than one based on process control. Although goal selection in theory may surpass process control, the two have never been directly compared, as we are reporting here. Eight young healthy human subjects participated in the present study, three trained and five naïve in BCI usage. Scalp-recorded electroencephalograms (EEG) were used to control a computer cursor during five different paradigms. The paradigms were similar in their underlying signal processing and used the same control signal. However, three were based on goal selection, and two on process control. For both the trained and naïve populations, goal selection had more hits per run, was faster, more accurate (for seven out of eight subjects) and had a higher information transfer rate than process control. Goal selection outperformed process control in every measure studied in the present investigation.

  17. Comparison between electric-field-navigated and line-navigated TMS for cortical motor mapping in patients with brain tumors.

    Science.gov (United States)

    Sollmann, Nico; Goblirsch-Kolb, Moritz F; Ille, Sebastian; Butenschoen, Vicki M; Boeckh-Behrens, Tobias; Meyer, Bernhard; Ringel, Florian; Krieg, Sandro M

    2016-12-01

    For the navigation of transcranial magnetic stimulation (TMS), various techniques are available. Yet, there are two basic principles underlying them all: electric-field-navigated transcranial magnetic stimulation (En-TMS) and line-navigated transcranial magnetic stimulation (Ln-TMS). The current study was designed to compare both methods. To explore whether there is a difference in clinical applicability, workflow, and mapping results of both techniques, we systematically compared motor mapping via En-TMS and Ln-TMS in 12 patients suffering from brain tumors. The number of motor-positive stimulation spots and the ratio of positive spots per overall stimulation numbers were significantly higher for En-TMS (motor-positive spots: En-TMS vs. Ln-TMS: 128.3 ± 35.0 vs. 41.3 ± 26.8, p mapping in the neurosurgical context for the first time. Although both TMS systems tested in the present study are explicitly designed for application during motor mapping in patients with brain lesions, there are differences in applicability, workflow, and results between En-TMS and Ln-TMS, which should be distinctly considered during clinical use of the technique. However, to draw final conclusions about accuracy, confirmation of motor-positive Ln-TMS spots by intraoperative stimulation is crucial within the scope of upcoming investigations.

  18. Improved Volitional Recall of Motor-Imagery-Related Brain Activation Patterns Using Real-Time Functional MRI-Based Neurofeedback.

    Science.gov (United States)

    Bagarinao, Epifanio; Yoshida, Akihiro; Ueno, Mika; Terabe, Kazunori; Kato, Shohei; Isoda, Haruo; Nakai, Toshiharu

    2018-01-01

    Motor imagery (MI), a covert cognitive process where an action is mentally simulated but not actually performed, could be used as an effective neurorehabilitation tool for motor function improvement or recovery. Recent approaches employing brain-computer/brain-machine interfaces to provide online feedback of the MI during rehabilitation training have promising rehabilitation outcomes. In this study, we examined whether participants could volitionally recall MI-related brain activation patterns when guided using neurofeedback (NF) during training. The participants' performance was compared to that without NF. We hypothesized that participants would be able to consistently generate the relevant activation pattern associated with the MI task during training with NF compared to that without NF. To assess activation consistency, we used the performance of classifiers trained to discriminate MI-related brain activation patterns. Our results showed significantly higher predictive values of MI-related activation patterns during training with NF. Additionally, this improvement in the classification performance tends to be associated with the activation of middle temporal gyrus/inferior occipital gyrus, a region associated with visual motion processing, suggesting the importance of performance monitoring during MI task training. Taken together, these findings suggest that the efficacy of MI training, in terms of generating consistent brain activation patterns relevant to the task, can be enhanced by using NF as a mechanism to enable participants to volitionally recall task-related brain activation patterns.

  19. Visual–motor integration and fine motor skills at 6½ years of age and associations with neonatal brain volumes in children born extremely preterm in Sweden: a population-based cohort study

    Science.gov (United States)

    Padilla, Nelly; Forsman, Lea; Broström, Lina; Hellgren, Kerstin; Åden, Ulrika

    2018-01-01

    Objectives This exploratory study aimed to investigate associations between neonatal brain volumes and visual–motor integration (VMI) and fine motor skills in children born extremely preterm (EPT) when they reached 6½ years of age. Setting Prospective population-based cohort study in Stockholm, Sweden, during 3 years. Participants All children born before gestational age, 27 weeks, during 2004–2007 in Stockholm, without major morbidities and impairments, and who underwent MRI at term-equivalent age. Main outcome measures Brain volumes were calculated using morphometric analyses in regions known to be involved in VMI and fine motor functions. VMI was assessed with The Beery-Buktenica Developmental Test of Visual–Motor Integration—sixth edition and fine motor skills were assessed with the manual dexterity subtest from the Movement Assessment Battery for Children—second edition, at 6½ years. Associations between the brain volumes and VMI and fine motor skills were evaluated using partial correlation, adjusted for total cerebral parenchyma and sex. Results Out of 107 children born at gestational age motor skills (r=0.54, P=0.01). Associations were also seen between fine motor skills and the volume of the cerebellum (r=0.42, P=0.02), brainstem (r=0.47, P=0.008) and grey matter (r=−0.38, P=0.04). Conclusions Neonatal brain volumes in areas known to be involved in VMI and fine motor skills were associated with scores for these two functions when children born EPT without major brain lesions or cerebral palsy were evaluated at 6½ years of age. Establishing clear associations between early brain volume alterations and later VMI and/or fine motor skills could make early interventions possible. PMID:29455171

  20. Incremental Adaptive Fuzzy Control for Sensorless Stroke Control of A Halbach-type Linear Oscillatory Motor

    Science.gov (United States)

    Lei, Meizhen; Wang, Liqiang

    2018-01-01

    The halbach-type linear oscillatory motor (HT-LOM) is multi-variable, highly coupled, nonlinear and uncertain, and difficult to get a satisfied result by conventional PID control. An incremental adaptive fuzzy controller (IAFC) for stroke tracking was presented, which combined the merits of PID control, the fuzzy inference mechanism and the adaptive algorithm. The integral-operation is added to the conventional fuzzy control algorithm. The fuzzy scale factor can be online tuned according to the load force and stroke command. The simulation results indicate that the proposed control scheme can achieve satisfied stroke tracking performance and is robust with respect to parameter variations and external disturbance.

  1. Neural Correlates of User-initiated Motor Success and Failure - A Brain-Computer Interface Perspective.

    Science.gov (United States)

    Yazmir, Boris; Reiner, Miriam

    2018-05-15

    Any motor action is, by nature, potentially accompanied by human errors. In order to facilitate development of error-tailored Brain-Computer Interface (BCI) correction systems, we focused on internal, human-initiated errors, and investigated EEG correlates of user outcome successes and errors during a continuous 3D virtual tennis game against a computer player. We used a multisensory, 3D, highly immersive environment. Missing and repelling the tennis ball were considered, as 'error' (miss) and 'success' (repel). Unlike most previous studies, where the environment "encouraged" the participant to perform a mistake, here errors happened naturally, resulting from motor-perceptual-cognitive processes of incorrect estimation of the ball kinematics, and can be regarded as user internal, self-initiated errors. Results show distinct and well-defined Event-Related Potentials (ERPs), embedded in the ongoing EEG, that differ across conditions by waveforms, scalp signal distribution maps, source estimation results (sLORETA) and time-frequency patterns, establishing a series of typical features that allow valid discrimination between user internal outcome success and error. The significant delay in latency between positive peaks of error- and success-related ERPs, suggests a cross-talk between top-down and bottom-up processing, represented by an outcome recognition process, in the context of the game world. Success-related ERPs had a central scalp distribution, while error-related ERPs were centro-parietal. The unique characteristics and sharp differences between EEG correlates of error/success provide the crucial components for an improved BCI system. The features of the EEG waveform can be used to detect user action outcome, to be fed into the BCI correction system. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. Control of a visual keyboard using an electrocorticographic brain-computer interface.

    Science.gov (United States)

    Krusienski, Dean J; Shih, Jerry J

    2011-05-01

    Brain-computer interfaces (BCIs) are devices that enable severely disabled people to communicate and interact with their environments using their brain waves. Most studies investigating BCI in humans have used scalp EEG as the source of electrical signals and focused on motor control of prostheses or computer cursors on a screen. The authors hypothesize that the use of brain signals obtained directly from the cortical surface will more effectively control a communication/spelling task compared to scalp EEG. A total of 6 patients with medically intractable epilepsy were tested for the ability to control a visual keyboard using electrocorticographic (ECOG) signals. ECOG data collected during a P300 visual task paradigm were preprocessed and used to train a linear classifier to subsequently predict the intended target letters. The classifier was able to predict the intended target character at or near 100% accuracy using fewer than 15 stimulation sequences in 5 of the 6 people tested. ECOG data from electrodes outside the language cortex contributed to the classifier and enabled participants to write words on a visual keyboard. This is a novel finding because previous invasive BCI research in humans used signals exclusively from the motor cortex to control a computer cursor or prosthetic device. These results demonstrate that ECOG signals from electrodes both overlying and outside the language cortex can reliably control a visual keyboard to generate language output without voice or limb movements.

  3. [Assessment of motor and sensory pathways of the brain using diffusion-tensor tractography in children with cerebral palsy].

    Science.gov (United States)

    Memedyarov, A M; Namazova-Baranova, L S; Ermolina, Y V; Anikin, A V; Maslova, O I; Karkashadze, M Z; Klochkova, O A

    2014-01-01

    Diffusion tensor tractography--a new method of magnetic resonance imaging, that allows to visualize the pathways of the brain and to study their structural-functional state. The authors investigated the changes in motor and sensory pathways of brain in children with cerebral palsy using routine magnetic resonance imaging and diffusion-tensor tractography. The main group consisted of 26 patients with various forms of cerebral palsy and the comparison group was 25 people with normal psychomotor development (aged 2 to 6 years) and MR-picture of the brain. Magnetic resonance imaging was performed on the scanner with the induction of a magnetic field of 1,5 Tesla. Coefficients of fractional anisotropy and average diffusion coefficient estimated in regions of the brain containing the motor and sensory pathways: precentral gyrus, posterior limb of the internal capsule, thalamus, posterior thalamic radiation and corpus callosum. Statistically significant differences (p cerebral palsy in relation to the comparison group. All investigated regions, the coefficients of fractional anisotropy in children with cerebral palsy were significantly lower, and the average diffusion coefficient, respectively, higher. These changes indicate a lower degree of ordering of the white matter tracts associated with damage and subsequent development of gliosis of varying severity in children with cerebral palsy. It is shown that microstructural damage localized in both motor and sensory tracts that plays a leading role in the development of the clinical picture of cerebral palsy.

  4. Imparting Motion to a Test Object Such as a Motor Vehicle in a Controlled Fashion

    Science.gov (United States)

    Southward, Stephen C. (Inventor); Reubush, Chandler (Inventor); Pittman, Bryan (Inventor); Roehrig, Kurt (Inventor); Gerard, Doug (Inventor)

    2014-01-01

    An apparatus imparts motion to a test object such as a motor vehicle in a controlled fashion. A base has mounted on it a linear electromagnetic motor having a first end and a second end, the first end being connected to the base. A pneumatic cylinder and piston combination have a first end and a second end, the first end connected to the base so that the pneumatic cylinder and piston combination is generally parallel with the linear electromagnetic motor. The second ends of the linear electromagnetic motor and pneumatic cylinder and piston combination being commonly linked to a mount for the test object. A control system for the linear electromagnetic motor and pneumatic cylinder and piston combination drives the pneumatic cylinder and piston combination to support a substantial static load of the test object and the linear electromagnetic motor to impart controlled motion to the test object.

  5. Motor and Nonmotor Circuitry Activation Induced by Subthalamic Nucleus Deep Brain Stimulation in Patients With Parkinson Disease: Intraoperative Functional Magnetic Resonance Imaging for Deep Brain Stimulation.

    Science.gov (United States)

    Knight, Emily J; Testini, Paola; Min, Hoon-Ki; Gibson, William S; Gorny, Krzysztof R; Favazza, Christopher P; Felmlee, Joel P; Kim, Inyong; Welker, Kirk M; Clayton, Daniel A; Klassen, Bryan T; Chang, Su-youne; Lee, Kendall H

    2015-06-01

    To test the hypothesis suggested by previous studies that subthalamic nucleus (STN) deep brain stimulation (DBS) in patients with Parkinson disease would affect the activity of motor and nonmotor networks, we applied intraoperative functional magnetic resonance imaging (fMRI) to patients receiving DBS. Ten patients receiving STN DBS for Parkinson disease underwent intraoperative 1.5-T fMRI during high-frequency stimulation delivered via an external pulse generator. The study was conducted between January 1, 2013, and September 30, 2014. We observed blood oxygen level-dependent (BOLD) signal changes (false discovery rate <0.001) in the motor circuitry (including the primary motor, premotor, and supplementary motor cortices; thalamus; pedunculopontine nucleus; and cerebellum) and in the limbic circuitry (including the cingulate and insular cortices). Activation of the motor network was observed also after applying a Bonferroni correction (P<.001) to the data set, suggesting that across patients, BOLD changes in the motor circuitry are more consistent compared with those occurring in the nonmotor network. These findings support the modulatory role of STN DBS on the activity of motor and nonmotor networks and suggest complex mechanisms as the basis of the efficacy of this treatment modality. Furthermore, these results suggest that across patients, BOLD changes in the motor circuitry are more consistent than those in the nonmotor network. With further studies combining the use of real-time intraoperative fMRI with clinical outcomes in patients treated with DBS, functional imaging techniques have the potential not only to elucidate the mechanisms of DBS functioning but also to guide and assist in the surgical treatment of patients affected by movement and neuropsychiatric disorders. clinicaltrials.gov Identifier: NCT01809613. Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  6. Modeling and Speed Control of Induction Motor Drives Using Neural Networks

    Directory of Open Access Journals (Sweden)

    V. Jamuna

    2010-08-01

    Full Text Available Speed control of induction motor drives using neural networks is presented. The mathematical model of single phase induction motor is developed. A new simulink model for a neural network-controlled bidirectional chopper fed single phase induction motor is proposed. Under normal operation, the true drive parameters are real-time identified and they are converted into the controller parameters through multilayer forward computation by neural networks. Comparative study has been made between the conventional and neural network controllers. It is observed that the neural network controlled drive system has better dynamic performance, reduced overshoot and faster transient response than the conventional controlled system.

  7. Compensatory cerebral motor control following presumed perinatal ischemic stroke

    NARCIS (Netherlands)

    van der Hoorn, Anouk; Potgieser, Adriaan R E; Brouwer, Oebele F; de Jong, Bauke M

    Case: A fifteen year-old left-handed girl presented with right-sided focal motor seizures. Neuroimaging showed a large left hemisphere lesion compatible with a middle cerebral artery stroke of presumed perinatal origin. She was not previously diagnosed with a motor deficit, although neurological

  8. Speech networks at rest and in action: interactions between functional brain networks controlling speech production

    Science.gov (United States)

    Fuertinger, Stefan

    2015-01-01

    Speech production is one of the most complex human behaviors. Although brain activation during speaking has been well investigated, our understanding of interactions between the brain regions and neural networks remains scarce. We combined seed-based interregional correlation analysis with graph theoretical analysis of functional MRI data during the resting state and sentence production in healthy subjects to investigate the interface and topology of functional networks originating from the key brain regions controlling speech, i.e., the laryngeal/orofacial motor cortex, inferior frontal and superior temporal gyri, supplementary motor area, cingulate cortex, putamen, and thalamus. During both resting and speaking, the interactions between these networks were bilaterally distributed and centered on the sensorimotor brain regions. However, speech production preferentially recruited the inferior parietal lobule (IPL) and cerebellum into the large-scale network, suggesting the importance of these regions in facilitation of the transition from the resting state to speaking. Furthermore, the cerebellum (lobule VI) was the most prominent region showing functional influences on speech-network integration and segregation. Although networks were bilaterally distributed, interregional connectivity during speaking was stronger in the left vs. right hemisphere, which may have underlined a more homogeneous overlap between the examined networks in the left hemisphere. Among these, the laryngeal motor cortex (LMC) established a core network that fully overlapped with all other speech-related networks, determining the extent of network interactions. Our data demonstrate complex interactions of large-scale brain networks controlling speech production and point to the critical role of the LMC, IPL, and cerebellum in the formation of speech production network. PMID:25673742

  9. Speech networks at rest and in action: interactions between functional brain networks controlling speech production.

    Science.gov (United States)

    Simonyan, Kristina; Fuertinger, Stefan

    2015-04-01

    Speech production is one of the most complex human behaviors. Although brain activation during speaking has been well investigated, our understanding of interactions between the brain regions and neural networks remains scarce. We combined seed-based interregional correlation analysis with graph theoretical analysis of functional MRI data during the resting state and sentence production in healthy subjects to investigate the interface and topology of functional networks originating from the key brain regions controlling speech, i.e., the laryngeal/orofacial motor cortex, inferior frontal and superior temporal gyri, supplementary motor area, cingulate cortex, putamen, and thalamus. During both resting and speaking, the interactions between these networks were bilaterally distributed and centered on the sensorimotor brain regions. However, speech production preferentially recruited the inferior parietal lobule (IPL) and cerebellum into the large-scale network, suggesting the importance of these regions in facilitation of the transition from the resting state to speaking. Furthermore, the cerebellum (lobule VI) was the most prominent region showing functional influences on speech-network integration and segregation. Although networks were bilaterally distributed, interregional connectivity during speaking was stronger in the left vs. right hemisphere, which may have underlined a more homogeneous overlap between the examined networks in the left hemisphere. Among these, the laryngeal motor cortex (LMC) established a core network that fully overlapped with all other speech-related networks, determining the extent of network interactions. Our data demonstrate complex interactions of large-scale brain networks controlling speech production and point to the critical role of the LMC, IPL, and cerebellum in the formation of speech production network. Copyright © 2015 the American Physiological Society.

  10. 76 FR 61095 - California State Motor Vehicle Pollution Control Standards; Within the Scope Determination and...

    Science.gov (United States)

    2011-10-03

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9474-5] California State Motor Vehicle Pollution Control... longer expected to produce fuel-cell vehicles to meet part of its gold vehicle credit requirements for... motor vehicle pollution control program. Because EPA has not received adverse public comment challenging...

  11. Motor Disorder and Anxious and Depressive Symptomatology: A Monozygotic Co-Twin Control Approach

    Science.gov (United States)

    Pearsall-Jones, Jillian G.; Piek, Jan P.; Rigoli, Daniela; Martin, Neilson C.; Levy, Florence

    2011-01-01

    The aim of this study was to investigate the relationship between poor motor ability and anxious and depressive symptomatology in child and adolescent monozygotic twins. The co-twin control design was used to explore these mental health issues in MZ twins concordant and discordant for a motor disorder, and controls. This methodology offers the…

  12. Interleaving subthalamic nucleus deep brain stimulation to avoid side effects while achieving satisfactory motor benefits in Parkinson disease

    Science.gov (United States)

    Zhang, Shizhen; Zhou, Peizhi; Jiang, Shu; Wang, Wei; Li, Peng

    2016-01-01

    Abstract Background: Deep brain stimulation (DBS) of the subthalamic nucleus is an effective treatment for advanced Parkinson disease (PD). However, achieving ideal outcomes by conventional programming can be difficult in some patients, resulting in suboptimal control of PD symptoms and stimulation-induced adverse effects. Interleaving stimulation (ILS) is a newer programming technique that can individually optimize the stimulation area, thereby improving control of PD symptoms while alleviating stimulation-induced side effects after conventional programming fails to achieve the desired results. Methods: We retrospectively reviewed PD patients who received DBS programming during the previous 4 years in our hospital. We collected clinical and demographic data from 12 patients who received ILS because of incomplete alleviation of PD symptoms or stimulation-induced adverse effects after conventional programming had proven ineffective or intolerable. Appropriate lead location was confirmed with postoperative reconstruction images. The rationale and clinical efficacy of ILS was analyzed. Results: We divided our patients into 4 groups based on the following symptoms: stimulation-induced dysarthria and choreoathetoid dyskinesias, gait disturbance, and incomplete control of parkinsonism. After treatment with ILS, patients showed satisfactory improvement in PD symptoms and alleviation of stimulation-induced side effects, with a mean improvement in Unified PD Rating Scale motor scores of 26.9%. Conclusions: ILS is a newer choice and effective programming strategy to maximize symptom control in PD while decreasing stimulation-induced adverse effects when conventional programming fails to achieve satisfactory outcome. However, we should keep in mind that most DBS patients are routinely treated with conventional stimulation and that not all patients benefit from ILS. ILS is not recommended as the first choice of programming, and it is recommended only when patients have

  13. Controlling a Four-Quadrant Brushless Three-Phase dc Motor

    Science.gov (United States)

    Nola, F. J.

    1986-01-01

    Control circuit commutates windings of brushless, three-phase, permanent-magnet motor operating from power supply. With single analog command voltage, controller makes motor accelerate, drive steadily, or brake regeneratively, in clockwise or counterclockwise direction. Controller well suited for use with energy-storage flywheels, actuators for aircraft-control surfaces, cranes, industrial robots, and other electromechanical systems requiring bidirectional control or sudden stopping and reversal.

  14. Linear switched reluctance motor control with PIC18F452 microcontroller

    OpenAIRE

    DURSUN, Mahir; KOÇ, Fatmagül

    2014-01-01

    This paper presents the simulation, control, and experimental results of the velocity of a double-sided, 6/4-poled, 3-phased, 8 A, 24 V, 250 W, and 250 N pull force linear switched reluctance motor (LSRM). In the simulation and experimental study, the reference velocity is constant depending on the position and time. The velocity versus the position of the translator was controlled with fuzzy logic control (FLC) and proportional-integral (PI) control techniques. The motor was control...

  15. Multi-Class Motor Imagery EEG Decoding for Brain-Computer Interfaces

    Science.gov (United States)

    Wang, Deng; Miao, Duoqian; Blohm, Gunnar

    2012-01-01

    Recent studies show that scalp electroencephalography (EEG) as a non-invasive interface has great potential for brain-computer interfaces (BCIs). However, one factor that has limited practical applications for EEG-based BCI so far is the difficulty to decode brain signals in a reliable and efficient way. This paper proposes a new robust processing framework for decoding of multi-class motor imagery (MI) that is based on five main processing steps. (i) Raw EEG segmentation without the need of visual artifact inspection. (ii) Considering that EEG recordings are often contaminated not just by electrooculography (EOG) but also other types of artifacts, we propose to first implement an automatic artifact correction method that combines regression analysis with independent component analysis for recovering the original source signals. (iii) The significant difference between frequency components based on event-related (de-) synchronization and sample entropy is then used to find non-contiguous discriminating rhythms. After spectral filtering using the discriminating rhythms, a channel selection algorithm is used to select only relevant channels. (iv) Feature vectors are extracted based on the inter-class diversity and time-varying dynamic characteristics of the signals. (v) Finally, a support vector machine is employed for four-class classification. We tested our proposed algorithm on experimental data that was obtained from dataset 2a of BCI competition IV (2008). The overall four-class kappa values (between 0.41 and 0.80) were comparable to other models but without requiring any artifact-contaminated trial removal. The performance showed that multi-class MI tasks can be reliably discriminated using artifact-contaminated EEG recordings from a few channels. This may be a promising avenue for online robust EEG-based BCI applications. PMID:23087607

  16. Fixed-Time Stability Analysis of Permanent Magnet Synchronous Motors with Novel Adaptive Control

    Directory of Open Access Journals (Sweden)

    Maoxing Liu

    2017-01-01

    Full Text Available We firstly investigate the fixed-time stability analysis of uncertain permanent magnet synchronous motors with novel control. Compared with finite-time stability where the convergence rate relies on the initial permanent magnet synchronous motors state, the settling time of fixed-time stability can be adjusted to desired values regardless of initial conditions. Novel adaptive stability control strategy for the permanent magnet synchronous motors is proposed, with which we can stabilize permanent magnet synchronous motors within fixed time based on the Lyapunov stability theory. Finally, some simulation and comparison results are given to illustrate the validity of the theoretical results.

  17. Wavelet-Fuzzy Speed Indirect Field Oriented Controller for Three-Phase AC Motor Drive

    DEFF Research Database (Denmark)

    Sanjeevikumar, Padmanaban; Daya, Febin; Blaabjerg, Frede

    2016-01-01

    Three-phase voltage source inverter driven induction motor are used in many medium- and high-power applications. Precision in speed of the motor play vital role, i.e. popular methods of direct/indirect field-oriented control (FOC) are applied. FOC is employed with proportional-integral (P...... wavelet transform and the fuzzy logic controller, to generate the scaled gains for the indirect FOC induction motor. Complete model of the proposed ac motor drive is developed with numerical simulation Matlab/Simulink software and tested under different working conditions. For experimental verification...

  18. A Study on Energy Saving of Single Phase Induction Motor By Voltage Control

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jong Moon [Pusan College of Information Technolgy, Pusan (Korea); Kim, Joon Hong [Dong Myong College, Pusan (Korea)

    2001-06-01

    This paper describes a simple effective method for energy saving of AC motors having a widely variable load. The proposed method is based on an optimal efficiency control which is operated by voltage-current pattern such as to maintain the maximum efficiency on the efficiency-output characteristics of the motor, TRIAC voltage control characteristics. The parameters of simplified voltage-current pattern can be determined approximately and reliably from the rated voltage and current of the motor. Experiments are focused on a single phase capacitor motor, the optimal energy saving are proved by proposed method. (author). 8 refs., 15 figs.

  19. A Novel Control Algorithm Expressions Set for not Negligible Resistive Parameters PM Brushless AC Motors

    Directory of Open Access Journals (Sweden)

    Renato RIZZO

    2012-08-01

    Full Text Available This paper deals with Permanent Magnet Brushless Motors. In particular is proposed a new set of control algorithm expressions that is realized taking into account resistive parameters of the motor, differently from simplified models of this type of motors where these parameters are usually neglected. The control is set up and an analysis of the performance is reported in the paper, where the validation of the new expressions is done with reference to a motor prototype particularly compact because is foreseen for application on tram propulsion drives. The results are evidenced in the last part of the paper.

  20. Mapping cortical hand motor representation using TMS: A method to assess brain plasticity and a surrogate marker for recovery of function after stroke?

    Science.gov (United States)

    Lüdemann-Podubecká, Jitka; Nowak, Dennis Alexander

    2016-10-01

    Stroke is associated with reorganization within motor areas of both hemispheres. Mapping the cortical hand motor representation using transcranial magnetic stimulation may help to understand the relationship between motor cortex reorganization and motor recovery of the affected hand after stroke. A standardized review of the pertinent literature was performed. We identified 20 trials, which analyzed the relationship between the extent and/or location of cortical hand motor representation using transcranial magnetic stimulation and motor function and recovery of the affected hand. Several correlations were found between cortical reorganization and measures of hand motor impairment and recovery. A better understanding of the relationships between the extent and location of cortical hand motor representation and the motor impairment and motor recovery of the affected hand after stroke may contribute to a targeted use of non-invasive brain stimulation protocols. In the future motor mapping may help to guide brain stimulation techniques to the most effective motor area in an affected individual. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Brain-controlled body movement assistance devices and methods

    Energy Technology Data Exchange (ETDEWEB)

    Leuthardt, Eric C.; Love, Lonnie J.; Coker, Rob; Moran, Daniel W.

    2017-01-10

    Methods, devices, systems, and apparatus, including computer programs encoded on a computer storage medium, for brain-controlled body movement assistance devices. In one aspect, a device includes a brain-controlled body movement assistance device with a brain-computer interface (BCI) component adapted to be mounted to a user, a body movement assistance component operably connected to the BCI component and adapted to be worn by the user, and a feedback mechanism provided in connection with at least one of the BCI component and the body movement assistance component, the feedback mechanism being configured to output information relating to a usage session of the brain-controlled body movement assistance device.

  2. UNIFIED CONTROL STRUCTURE OF MULTI-TYPE INTERIOR PERMANENT MAGNET MOTOR

    Directory of Open Access Journals (Sweden)

    M. NORHISAM

    2015-03-01

    Full Text Available This paper presents the control strategy structure to extract the speed torque characteristic for the newly designed three phase Multi Type Interior Permanent Magnet Motor. The proposed structure with the driving circuits exhibit the performance of torque characteristics of the stepper motor and brushless motor with independent coil winding per phase especially used as an in-wheel motor in agricultural applications. Brushless Direct Current motors exhibit characteristics of generating high torque at high speed while the Permanent Magnet Stepper motors has characteristic of generating high torque at low speed. The typical characteristics of the above two are integrated in the proposed structure with a complex control structure that handle the switching complexity and speed control in real time. Thus, a specially designed driving system is essential to drive and control this special motor. The evaluation of the motor mechanical characteristics when applying load torque is also presented. The result determines the practical torque range applicable for each motor configuration and as combined machine.

  3. Visual-motor integration and fine motor skills at 6½ years of age and associations with neonatal brain volumes in children born extremely preterm in Sweden: a population-based cohort study.

    Science.gov (United States)

    Bolk, Jenny; Padilla, Nelly; Forsman, Lea; Broström, Lina; Hellgren, Kerstin; Åden, Ulrika

    2018-02-17

    This exploratory study aimed to investigate associations between neonatal brain volumes and visual-motor integration (VMI) and fine motor skills in children born extremely preterm (EPT) when they reached 6½ years of age. Prospective population-based cohort study in Stockholm, Sweden, during 3 years. All children born before gestational age, 27 weeks, during 2004-2007 in Stockholm, without major morbidities and impairments, and who underwent MRI at term-equivalent age. Brain volumes were calculated using morphometric analyses in regions known to be involved in VMI and fine motor functions. VMI was assessed with The Beery-Buktenica Developmental Test of Visual-Motor Integration-sixth edition and fine motor skills were assessed with the manual dexterity subtest from the Movement Assessment Battery for Children-second edition, at 6½ years. Associations between the brain volumes and VMI and fine motor skills were evaluated using partial correlation, adjusted for total cerebral parenchyma and sex. Out of 107 children born at gestational age skills (r=0.54, P=0.01). Associations were also seen between fine motor skills and the volume of the cerebellum (r=0.42, P=0.02), brainstem (r=0.47, P=0.008) and grey matter (r=-0.38, P=0.04). Neonatal brain volumes in areas known to be involved in VMI and fine motor skills were associated with scores for these two functions when children born EPT without major brain lesions or cerebral palsy were evaluated at 6½ years of age. Establishing clear associations between early brain volume alterations and later VMI and/or fine motor skills could make early interventions possible. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Hemispheric speech lateralisation in the developing brain is related to motor praxis ability

    Directory of Open Access Journals (Sweden)

    Jessica C. Hodgson

    2016-12-01

    Full Text Available Commonly displayed functional asymmetries such as hand dominance and hemispheric speech lateralisation are well researched in adults. However there is debate about when such functions become lateralised in the typically developing brain. This study examined whether patterns of speech laterality and hand dominance were related and whether they varied with age in typically developing children. 148 children aged 3–10 years performed an electronic pegboard task to determine hand dominance; a subset of 38 of these children also underwent functional Transcranial Doppler (fTCD imaging to derive a lateralisation index (LI for hemispheric activation during speech production using an animation description paradigm. There was no main effect of age in the speech laterality scores, however, younger children showed a greater difference in performance between their hands on the motor task. Furthermore, this between-hand performance difference significantly interacted with direction of speech laterality, with a smaller between-hand difference relating to increased left hemisphere activation. This data shows that both handedness and speech lateralisation appear relatively determined by age 3, but that atypical cerebral lateralisation is linked to greater performance differences in hand skill, irrespective of age. Results are discussed in terms of the common neural systems underpinning handedness and speech lateralisation.

  5. Optimizing spatial patterns with sparse filter bands for motor-imagery based brain-computer interface.

    Science.gov (United States)

    Zhang, Yu; Zhou, Guoxu; Jin, Jing; Wang, Xingyu; Cichocki, Andrzej

    2015-11-30

    Common spatial pattern (CSP) has been most popularly applied to motor-imagery (MI) feature extraction for classification in brain-computer interface (BCI) application. Successful application of CSP depends on the filter band selection to a large degree. However, the most proper band is typically subject-specific and can hardly be determined manually. This study proposes a sparse filter band common spatial pattern (SFBCSP) for optimizing the spatial patterns. SFBCSP estimates CSP features on multiple signals that are filtered from raw EEG data at a set of overlapping bands. The filter bands that result in significant CSP features are then selected in a supervised way by exploiting sparse regression. A support vector machine (SVM) is implemented on the selected features for MI classification. Two public EEG datasets (BCI Competition III dataset IVa and BCI Competition IV IIb) are used to validate the proposed SFBCSP method. Experimental results demonstrate that SFBCSP help improve the classification performance of MI. The optimized spatial patterns by SFBCSP give overall better MI classification accuracy in comparison with several competing methods. The proposed SFBCSP is a potential method for improving the performance of MI-based BCI. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Hybrid EEG-fNIRS Asynchronous Brain-Computer Interface for Multiple Motor Tasks.

    Directory of Open Access Journals (Sweden)

    Alessio Paolo Buccino

    Full Text Available Non-invasive Brain-Computer Interfaces (BCI have demonstrated great promise for neuroprosthetics and assistive devices. Here we aim to investigate methods to combine Electroencephalography (EEG and functional Near-Infrared Spectroscopy (fNIRS in an asynchronous Sensory Motor rhythm (SMR-based BCI. We attempted to classify 4 different executed movements, namely, Right-Arm-Left-Arm-Right-Hand-Left-Hand tasks. Previous studies demonstrated the benefit of EEG-fNIRS combination. However, since normally fNIRS hemodynamic response shows a long delay, we investigated new features, involving slope indicators, in order to immediately detect changes in the signals. Moreover, Common Spatial Patterns (CSPs have been applied to both EEG and fNIRS signals. 15 healthy subjects took part in the experiments and since 25 trials per class were available, CSPs have been regularized with information from the entire population of participants and optimized using genetic algorithms. The different features have been compared in terms of performance and the dynamic accuracy over trials shows that the introduced methods diminish the fNIRS delay in the detection of changes.

  7. Achieving a hybrid brain-computer interface with tactile selective attention and motor imagery

    Science.gov (United States)

    Ahn, Sangtae; Ahn, Minkyu; Cho, Hohyun; Jun, Sung Chan

    2014-12-01

    Objective. We propose a new hybrid brain-computer interface (BCI) system that integrates two different EEG tasks: tactile selective attention (TSA) using a vibro-tactile stimulator on the left/right finger and motor imagery (MI) of left/right hand movement. Event-related desynchronization (ERD) from the MI task and steady-state somatosensory evoked potential (SSSEP) from the TSA task are retrieved and combined into two hybrid senses. Approach. One hybrid approach is to measure two tasks simultaneously; the features of each task are combined for testing. Another hybrid approach is to measure two tasks consecutively (TSA first and MI next) using only MI features. For comparison with the hybrid approaches, the TSA and MI tasks are measured independently. Main results. Using a total of 16 subject datasets, we analyzed the BCI classification performance for MI, TSA and two hybrid approaches in a comparative manner; we found that the consecutive hybrid approach outperformed the others, yielding about a 10% improvement in classification accuracy relative to MI alone. It is understood that TSA may play a crucial role as a prestimulus in that it helps to generate earlier ERD prior to MI and thus sustains ERD longer and to a stronger degree; this ERD may give more discriminative information than ERD in MI alone. Significance. Overall, our proposed consecutive hybrid approach is very promising for the development of advanced BCI systems.

  8. Binary particle swarm optimization for frequency band selection in motor imagery based brain-computer interfaces.

    Science.gov (United States)

    Wei, Qingguo; Wei, Zhonghai

    2015-01-01

    A brain-computer interface (BCI) enables people suffering from affective neurological diseases to communicate with the external world. Common spatial pattern (CSP) is an effective algorithm for feature extraction in motor imagery based BCI systems. However, many studies have proved that the performance of CSP depends heavily on the frequency band of EEG signals used for the construction of covariance matrices. The use of different frequency bands to extract signal features may lead to different classification performances, which are determined by the discriminative and complementary information they contain. In this study, the broad frequency band (8-30 Hz) is divided into 10 sub-bands of band width 4 Hz and overlapping 2 Hz. Binary particle swarm optimization (BPSO) is used to find the best sub-band set to improve the performance of CSP and subsequent classification. Experimental results demonstrate that the proposed method achieved an average improvement of 6.91% in cross-validation accuracy when compared to broad band CSP.

  9. Brain N-acetylaspartate levels correlate with motor function in metachromatic leukodystrophy

    DEFF Research Database (Denmark)

    í Dali, Christine; Hanson, Lars G.; Barton, N. W.

    2010-01-01

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