Hardware Development and Locomotion Control Strategy for an Over-Ground Gait Trainer: NaTUre-Gaits.

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Luu, Trieu Phat; Low, Kin Huat; Qu, Xingda; Lim, Hup Boon; Hoon, Kay Hiang

2014-01-01

Therapist-assisted body weight supported (TABWS) gait rehabilitation was introduced two decades ago. The benefit of TABWS in functional recovery of walking in spinal cord injury and stroke patients has been demonstrated and reported. However, shortage of therapists, labor-intensiveness, and short duration of training are some limitations of this approach. To overcome these deficiencies, robotic-assisted gait rehabilitation systems have been suggested. These systems have gained attentions from researchers and clinical practitioner in recent years. To achieve the same objective, an over-ground gait rehabilitation system, NaTUre-gaits, was developed at the Nanyang Technological University. The design was based on a clinical approach to provide four main features, which are pelvic motion, body weight support, over-ground walking experience, and lower limb assistance. These features can be achieved by three main modules of NaTUre-gaits: 1) pelvic assistance mechanism, mobile platform, and robotic orthosis. Predefined gait patterns are required for a robotic assisted system to follow. In this paper, the gait pattern planning for NaTUre-gaits was accomplished by an individual-specific gait pattern prediction model. The model generates gait patterns that resemble natural gait patterns of the targeted subjects. The features of NaTUre-gaits have been demonstrated by walking trials with several subjects. The trials have been evaluated by therapists and doctors. The results show that 10-m walking trial with a reduction in manpower. The task-specific repetitive training approach and natural walking gait patterns were also successfully achieved.

Performance of spinal cord injury individuals while standing with the Mohammad Taghi Karimi reciprocal gait orthosis (MTK-RGO)

International Nuclear Information System (INIS)

Karimi, Mohammad Taghi; Amiri, Pouya; Esrafilian, Amir; Sedigh, Jafar; Fatoye, Francis

2013-01-01

Most patients with spinal cord injury use a wheelchair to transfer from place to place, however they need to stand and walk with orthosis to improve their health status. Although many orthoses have been designed for paraplegic patients, they have experienced various problems while in use. A new type of reciprocal gait orthosis was designed in the Bioengineering Unit of Strathclyde University to solve the problems of the available orthoses. Since there was no research undertaken regarding testing of the new orthosis on paraplegic subjects, this study was aimed to evaluate the new orthosis during standing of paraplegic subjects. Five paraplegic patients with lesion level between T12 and L1 and aged matched normal subjects were recruited into this study. The stability of subjects was evaluated during quiet standing and while undertaking hand tasks during standing with the new orthosis and the knee ankle foot orthosis (KAFO). The difference between the performances of paraplegic subjects while standing with both orthoses, and between the function of normal and paraplegic subjects were compared using the paired t test and independent sample t test, respectively. The stability of paraplegic subjects in standing with the new orthosis was better than that of the KAFO orthosis (p < 0.05). Moreover, the force applied on the crutch differed between the orthoses. The functional performance of paraplegic subjects was better with the new orthosis compared with normal subjects. The performance of paraplegic subjects while standing with the new orthosis was better than the KAFO. Therefore, the new orthosis may be useful to improve standing and walking in patients with paraplegia.

Biofeedback for robotic gait rehabilitation

Directory of Open Access Journals (Sweden)

Colombo Gery

2007-01-01

Full Text Available Abstract Background Development and increasing acceptance of rehabilitation robots as well as advances in technology allow new forms of therapy for patients with neurological disorders. Robot-assisted gait therapy can increase the training duration and the intensity for the patients while reducing the physical strain for the therapist. Optimal training effects during gait therapy generally depend on appropriate feedback about performance. Compared to manual treadmill therapy, there is a loss of physical interaction between therapist and patient with robotic gait retraining. Thus, it is difficult for the therapist to assess the necessary feedback and instructions. The aim of this study was to define a biofeedback system for a gait training robot and test its usability in subjects without neurological disorders. Methods To provide an overview of biofeedback and motivation methods applied in gait rehabilitation, previous publications and results from our own research are reviewed. A biofeedback method is presented showing how a rehabilitation robot can assess the patients' performance and deliver augmented feedback. For validation, three subjects without neurological disorders walked in a rehabilitation robot for treadmill training. Several training parameters, such as body weight support and treadmill speed, were varied to assess the robustness of the biofeedback calculation to confounding factors. Results The biofeedback values correlated well with the different activity levels of the subjects. Changes in body weight support and treadmill velocity had a minor effect on the biofeedback values. The synchronization of the robot and the treadmill affected the biofeedback values describing the stance phase. Conclusion Robot-aided assessment and feedback can extend and improve robot-aided training devices. The presented method estimates the patients' gait performance with the use of the robot's existing sensors, and displays the resulting biofeedback

Inducing self-selected human engagement in robotic locomotion training.

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Collins, Steven H; Jackson, Rachel W

2013-06-01

Stroke leads to severe mobility impairments for millions of individuals each year. Functional outcomes can be improved through manual treadmill therapy, but high costs limit patient exposure and, thereby, outcomes. Robotic gait training could increase the viable duration and frequency of training sessions, but robotic approaches employed thus far have been less effective than manual therapy. These shortcomings may relate to subconscious energy-minimizing drives, which might cause patients to engage less actively in therapy when provided with corrective robotic assistance. We have devised a new method for gait rehabilitation that harnesses, rather than fights, least-effort tendencies. Therapeutic goals, such as increased use of the paretic limb, are made easier than the patient's nominal gait through selective assistance from a robotic platform. We performed a pilot test on a healthy subject (N = 1) in which altered self-selected stride length was induced using a tethered robotic ankle-foot orthosis. The subject first walked on a treadmill while wearing the orthosis with and without assistance at unaltered and voluntarily altered stride length. Voluntarily increasing stride length by 5% increased metabolic energy cost by 4%. Robotic assistance decreased energy cost at both unaltered and voluntarily increased stride lengths, by 6% and 8% respectively. We then performed a test in which the robotic system continually monitored stride length and provided more assistance if the subject's stride length approached a target increase. This adaptive assistance protocol caused the subject to slowly adjust their gait patterns towards the target, leading to a 4% increase in stride length. Metabolic energy consumption was simultaneously reduced by 5%. These results suggest that selective-assistance protocols based on targets relevant to rehabilitation might lead patients to self-select desirable gait patterns during robotic gait training sessions, possibly facilitating better

Virtual Reality to control active participation in a subacute stroke patient during robot-assisted gait training.

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Bergmann, J; Krewer, C; Müller, F; Koenig, A; Riener, R

2011-01-01

Virtual Reality (VR) provides a promising medium to enrich robot assisted rehabilitation. VR applications present the opportunity to engage patients in therapy and control participation. The aim of this study was to investigate two strategies to control active participation of a stroke patient focusing on the involvement of the paretic leg in task solution. A subacute stroke patient with a severe hemiparesis performed two experiments on the driven gait orthosis Lokomat. Patient activity was quantified by weighted interaction torques measured in both legs (experiment A) and the paretic leg only (experiment B). The patient was able to successfully implement both the bilateral and unilateral control modality. Both control modes increased the motor output of the paretic leg, however the paretic leg control mode resulted in a much more differentiated regulation of the activity in the leg. Both control modes are appropriate approaches to enhance active participation and increase motor output in the paretic leg. Further research should evaluate the therapeutic benefit of patients with hemiparesis using the unilateral control mode depending on the severity of their impairment. © 2011 IEEE

Gait performance and foot pressure distribution during wearable robot-assisted gait in elderly adults.

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Lee, Su-Hyun; Lee, Hwang-Jae; Chang, Won Hyuk; Choi, Byung-Ok; Lee, Jusuk; Kim, Jeonghun; Ryu, Gyu-Ha; Kim, Yun-Hee

2017-11-28

A robotic exoskeleton device is an intelligent system designed to improve gait performance and quality of life for the wearer. Robotic technology has developed rapidly in recent years, and several robot-assisted gait devices were developed to enhance gait function and activities of daily living in elderly adults and patients with gait disorders. In this study, we investigated the effects of the Gait-enhancing Mechatronic System (GEMS), a new wearable robotic hip-assist device developed by Samsung Electronics Co, Ltd., Korea, on gait performance and foot pressure distribution in elderly adults. Thirty elderly adults who had no neurological or musculoskeletal abnormalities affecting gait participated in this study. A three-dimensional (3D) motion capture system, surface electromyography and the F-Scan system were used to collect data on spatiotemporal gait parameters, muscle activity and foot pressure distribution under three conditions: free gait without robot assistance (FG), robot-assisted gait with zero torque (RAG-Z) and robot-assisted gait (RAG). We found increased gait speed, cadence, stride length and single support time in the RAG condition. Reduced rectus femoris and medial gastrocnemius muscle activity throughout the terminal stance phase and reduced effort of the medial gastrocnemius muscle throughout the pre-swing phase were also observed in the RAG condition. In addition, walking with the assistance of GEMS resulted in a significant increase in foot pressure distribution, specifically in maximum force and peak pressure of the total foot, medial masks, anterior masks and posterior masks. The results of the present study reveal that GEMS may present an alternative way of restoring age-related changes in gait such as gait instability with muscle weakness, reduced step force and lower foot pressure in elderly adults. In addition, GEMS improved gait performance by improving push-off power and walking speed and reducing muscle activity in the lower

Development of body weight support gait training system using antagonistic bi-articular muscle model.

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Shibata, Yoshiyuki; Imai, Shingo; Nobutomo, Tatsuya; Miyoshi, Tasuku; Yamamoto, Shin-Ichiroh

2010-01-01

The purpose of this study is to develop a body weight support gait training system for stroke and spinal cord injury. This system consists of a powered orthosis, treadmill and equipment of body weight support. Attachment of the powered orthosis is able to fit subject who has difference of body size. This powered orthosis is driven by pneumatic McKibben actuator. Actuators are arranged as pair of antagonistic bi-articular muscle model and two pairs of antagonistic mono-articular muscle model like human musculoskeletal system. Part of the equipment of body weight support suspend subject by wire harness, and body weight of subject is supported continuously by counter weight. The powered orthosis is attached equipment of body weight support by parallel linkage, and movement of the powered orthosis is limited at sagittal plane. Weight of the powered orthosis is compensated by parallel linkage with gas-spring. In this study, we developed system that has orthosis powered by pneumatic McKibben actuators and equipment of body weight support. We report detail of our developed body weight support gait training system.

Mechanical performance of artificial pneumatic muscles to power an ankle-foot orthosis.

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Gordon, Keith E; Sawicki, Gregory S; Ferris, Daniel P

2006-01-01

We developed a powered ankle-foot orthosis that uses artificial pneumatic muscles to produce active plantar flexor torque. The purpose of this study was to quantify the mechanical performance of the orthosis during human walking. Three subjects walked at a range of speeds wearing ankle-foot orthoses with either one or two artificial muscles working in parallel. The orthosis produced similar total peak plantar flexor torque and network across speeds independent of the number of muscles used. The orthosis generated approximately 57% of the peak ankle plantar flexor torque during stance and performed approximately 70% of the positive plantar flexor work done during normal walking. Artificial muscle bandwidth and force-length properties were the two primary factors limiting torque production. The lack of peak force and work differences between single and double muscle conditions can be explained by force-length properties. Subjects altered their ankle kinematics between conditions resulting in changes in artificial muscle length. In the double muscle condition greater plantar flexion yielded shorter artificial muscles lengths and decreased muscle forces. This finding emphasizes the importance of human testing in the design and development of robotic exoskeleton devices for assisting human movement. The results of this study outline the mechanical performance limitations of an ankle-foot orthosis powered by artificial pneumatic muscles. This orthosis could be valuable for gait rehabilitation and for studies investigating neuromechanical control of human walking.

Trainer variability during step training after spinal cord injury: Implications for robotic gait-training device design.

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Galvez, Jose A; Budovitch, Amy; Harkema, Susan J; Reinkensmeyer, David J

2011-01-01

Robotic devices are being developed to automate repetitive aspects of walking retraining after neurological injuries, in part because they might improve the consistency and quality of training. However, it is unclear how inconsistent manual training actually is or whether stepping quality depends strongly on the trainers' manual skill. The objective of this study was to quantify trainer variability of manual skill during step training using body-weight support on a treadmill and assess factors of trainer skill. We attached a sensorized orthosis to one leg of each patient with spinal cord injury and measured the shank kinematics and forces exerted by different trainers during six training sessions. An expert trainer rated the trainers' skill level based on videotape recordings. Between-trainer force variability was substantial, about two times greater than within-trainer variability. Trainer skill rating correlated strongly with two gait features: better knee extension during stance and fewer episodes of toe dragging. Better knee extension correlated directly with larger knee horizontal assistance force, but better toe clearance did not correlate with larger ankle push-up force; rather, it correlated with better knee and hip extension. These results are useful to inform robotic gait-training design.

Locomotion Gait Planning of Climber Snake-Like Robot

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Mohammad Nezaminia

2013-04-01

Full Text Available In this article a novel breed of snake-like climber robots has been introduced. Structure and operation of the first generation of snake-like climber robot "Marak I" has been discussed. The gait planning for two dimensional locomotion of a novel snake-like climber robot "Marak I" is presented. The types of locomotion investigated were rectilinear and wheeling gaits. The gaits of locomotion were experimented and their suitability for various applications has been mentioned. Some encountered practical problems plus solutions were addressed. Finally we found out that: the vertical motion was producing more fault than horizontal locomotion, and notably the fastest gait of locomotion was the wheeling gait

Hip orthosis powered by pneumatic artificial muscle: voluntary activation in absence of myoelectrical signal.

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do Nascimento, Breno Gontijo; Vimieiro, Claysson Bruno Santos; Nagem, Danilo Alves Pinto; Pinotti, Marcos

2008-04-01

Powered orthosis is a special class of gait assist device that employs a mechanical or electromechanical actuator to enhance movement of hip, knee, or ankle articulations. Pneumatic artificial muscle (PAM) has been suggested as a pneumatic actuator because its performance is similar to biological muscle. The electromyography (EMG) signal interpretation is the most popular and simplest method to establish the patient voluntary control of the orthosis. However, this technique is not suitable for patients presenting neurological lesions causing absence or very low quality of EMG signal. For those cases, an alternative control strategy should be provided. The aim of the present study is to develop a gait assistance orthosis for lower limb powered by PAMs controlled by a voluntary activation method based on the angular behavior of hip joint. In the present study, an orthosis that has been molded in a patient was employed and, by taking her anthropometric parameters and movement constraints, the adaptation of the existing orthosis to the powered orthosis was planned. A control system was devised allowing voluntary control of a powered orthosis suitable for patients presenting neurological lesions causing absence or very low quality of EMG signal. A pilot clinical study was reported where a patient, victim of poliovirus, successfully tested a hip orthosis especially modified for the gait test evaluation in the parallel bar system. The hip orthosis design and the control circuitry parameters were able to be set to provide satisfactory and comfortable use of the orthosis during the gait cycle.

The effects of gait training using powered lower limb exoskeleton robot on individuals with complete spinal cord injury.

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Wu, Cheng-Hua; Mao, Hui-Fen; Hu, Jwu-Sheng; Wang, Ting-Yun; Tsai, Yi-Jeng; Hsu, Wei-Li

2018-03-05

Powered exoskeleton can improve the mobility for people with movement deficits by providing mechanical support and facilitate the gait training. This pilot study evaluated the effect of gait training using a newly developed powered lower limb exoskeleton robot for individuals with complete spinal cord injury (SCI). Two participants with a complete SCI were recruited for this clinical study. The powered exoskeleton gait training was 8 weeks, 1 h per session, and 2 sessions per week. The evaluation was performed before and after the training for (1) the time taken by the user to don and doff the powered exoskeleton independently, (2) the level of exertion perceived by participants while using the powered exoskeleton, and (3) the mobility performance included the timed up-and-go test, 10-m walk test, and 6-min walk test with the powered exoskeleton. The safety of the powered exoskeleton was evaluated on the basis of injury reports and the incidence of falls or imbalance while using the device. The results indicated that the participants were donning and doffing the powered lower limb exoskeleton robot independently with a lower level of exertion and walked faster and farther without any injury or fall incidence when using the powered exoskeleton than when using a knee-ankle-foot orthosis. Bone mineral densities was also increased after the gait training. No adverse effects, such as skin abrasions, or discomfort were reported while using the powered exoskeleton. The findings demonstrated that individuals with complete SCI used the powered lower limb exoskeleton robot independently without any assistance after 8 weeks of powered exoskeleton gait training. Trial registration: National Taiwan University Hospital. 201210051RIB . Name of registry: Hui-Fen Mao. URL of registry: Not available. Date of registration: December 12th, 2012. Date of enrolment of the first participant to the trial: January 3rd, 2013.

Does robotic gait training improve balance in Parkinson's disease? A randomized controlled trial.

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Picelli, Alessandro; Melotti, Camilla; Origano, Francesca; Waldner, Andreas; Gimigliano, Raffaele; Smania, Nicola

2012-09-01

Treadmill training (with or without robotic assistance) has been reported to improve balance skills in patients with Parkinson's disease (PD). However, its effectiveness on postural instability has been evaluated mainly in patients with mild to moderate PD (Hoehn & Yahr stage ≤3). Patients with more severe disease may benefit from robot-assisted gait training performed by the Gait-Trainer GT1, as a harness supports them with their feet placed on motor-driven footplates. The aim of this study was to determine whether robot-assisted gait training could have a positive influence on postural stability in patients with PD at Hoehn & Yahr stage 3-4. Thirty-four patients with PD at Hoehn & Yahr stage 3-4 were randomly assigned into two groups. All patients received twelve, 40-min treatment sessions, three days/week, for four consecutive weeks. The Robotic Training group (n = 17) underwent robot-assisted gait training, while the Physical Therapy group (n = 17) underwent a training program not specifically aimed at improving postural stability. Patients were evaluated before, immediately after and 1-month post-treatment. Primary outcomes were: Berg Balance scale; Nutt's rating. A significant improvement was found after treatment on the Berg Balance Scale and the Nutt's rating in favor of the Robotic Training group (Berg: 43.44 ± 2.73; Nutt: 1.38 ± 0.50) compared to the Physical Therapy group (Berg: 37.27 ± 5.68; Nutt: 2.07 ± 0.59). All improvements were maintained at the 1-month follow-up evaluation. Robot-assisted gait training may improve postural instability in patients with PD at Hoehn & Yahr stage 3-4. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mina: A Sensorimotor Robotic Orthosis for Mobility Assistance

OpenAIRE

Raj, Anil K.; Neuhaus, Peter D.; Moucheboeuf, Adrien M.; Noorden, Jerryll H.; Lecoutre, David V.

2011-01-01

While most mobility options for persons with paraplegia or paraparesis employ wheeled solutions, significant adverse health, psychological, and social consequences result from wheelchair confinement. Modern robotic exoskeleton devices for gait assistance and rehabilitation, however, can support legged locomotion systems for those with lower extremity weakness or paralysis. The Florida Institute for Human and Machine Cognition (IHMC) has developed the Mina, a prototype sensorimotor robotic ort...

The influence of a powered knee-ankle-foot orthosis on walking in poliomyelitis subjects: A pilot study.

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Arazpour, Mokhtar; Moradi, Alireza; Samadian, Mohammad; Bahramizadeh, Mahmood; Joghtaei, Mahmoud; Ahmadi Bani, Monireh; Hutchins, Stephen W; Mardani, Mohammad A

2016-06-01

Traditionally, the anatomical knee joint is locked in extension when walking with a conventional knee-ankle-foot orthosis. A powered knee-ankle-foot orthosis was developed to provide restriction of knee flexion during stance phase and active flexion and extension of the knee during swing phase of gait. The purpose of this study was to determine differences of the powered knee-ankle-foot orthosis compared to a locked knee-ankle-foot orthosis in kinematic data and temporospatial parameters during ambulation. Quasi-experimental design. Subjects with poliomyelitis (n = 7) volunteered for this study and undertook gait analysis with both the powered and the conventional knee-ankle-foot orthoses. Three trials per orthosis were collected while each subject walked along a 6-m walkway using a calibrated six-camera three-dimensional video-based motion analysis system. Walking with the powered knee-ankle-foot orthosis resulted in a significant reduction in both walking speed and step length (both 18%), but a significant increase in stance phase percentage compared to walking with the conventional knee-ankle-foot orthosis. Cadence was not significantly different between the two test conditions (p = 0.751). There was significantly higher knee flexion during swing phase and increased hip hiking when using the powered orthosis. The new powered orthosis permitted improved knee joint kinematic for knee-ankle-foot orthosis users while providing knee support in stance and active knee motion in swing in the gait cycle. Therefore, the new powered orthosis provided more natural knee flexion during swing for orthosis users compared to the locked knee-ankle-foot orthosis. This orthosis has the potential to improve knee joint kinematics and gait pattern in poliomyelitis subjects during walking activities. © The International Society for Prosthetics and Orthotics 2015.

Does robot-assisted gait rehabilitation improve balance in stroke patients? A systematic review.

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Swinnen, Eva; Beckwée, David; Meeusen, Romain; Baeyens, Jean-Pierre; Kerckhofs, Eric

2014-01-01

The aim of this systematic review was to summarize the improvements in balance after robot-assisted gait training (RAGT) in stroke patients. Two databases were searched: PubMed and Web of Knowledge. The most important key words are "stroke," "RAGT," "balance," "Lokomat," and "gait trainer." Studies were included if stroke patients were involved in RAGT protocols, and balance was determined as an outcome measurement. The articles were checked for methodological quality by 2 reviewers (Cohen's κ = 0.72). Nine studies were included (7 true experimental and 2 pre-experimental studies; methodological quality score, 56%-81%). In total, 229 subacute or chronic stroke patients (70.5% male) were involved in RAGT (3 to 5 times per week, 3 to 10 weeks, 12 to 25 sessions). In 5 studies, the gait trainer was used; in 2, the Lokomat was used; in 1 study, a single-joint wearable knee orthosis was used; and in 1 study, the AutoAmbulator was used. Eight studies compared RAGT with other gait rehabilitation methods. Significant improvements (no to large effect sizes, Cohen's d = 0.01 to 3.01) in balance scores measured with the Berg Balance Scale, the Tinetti test, postural sway tests, and the Timed Up and Go test were found after RAGT. No significant differences in balance between the intervention and control groups were reported. RAGT can lead to improvements in balance in stroke patients; however, it is not clear whether the improvements are greater compared with those associated with other gait rehabilitation methods. Because a limited number of studies are available, more specific research (eg, randomized controlled trials with larger, specific populations) is necessary to draw stronger conclusions.

Energy Expenditure of Trotting Gait Under Different Gait Parameters

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Chen, Xian-Bao; Gao, Feng

2017-07-01

Robots driven by batteries are clean, quiet, and can work indoors or in space. However, the battery endurance is a great problem. A new gait parameter design energy saving strategy to extend the working hours of the quadruped robot is proposed. A dynamic model of the robot is established to estimate and analyze the energy expenditures during trotting. Given a trotting speed, optimal stride frequency and stride length can minimize the energy expenditure. However, the relationship between the speed and the optimal gait parameters is nonlinear, which is difficult for practical application. Therefore, a simplified gait parameter design method for energy saving is proposed. A critical trotting speed of the quadruped robot is found and can be used to decide the gait parameters. When the robot is travelling lower than this speed, it is better to keep a constant stride length and change the cycle period. When the robot is travelling higher than this speed, it is better to keep a constant cycle period and change the stride length. Simulations and experiments on the quadruped robot show that by using the proposed gait parameter design approach, the energy expenditure can be reduced by about 54% compared with the 100 mm stride length under 500 mm/s speed. In general, an energy expenditure model based on the gait parameter of the quadruped robot is built and the trotting gait parameters design approach for energy saving is proposed.

Does robot-assisted gait training ameliorate gait abnormalities in multiple sclerosis? A pilot randomized-control trial.

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Straudi, S; Benedetti, M G; Venturini, E; Manca, M; Foti, C; Basaglia, N

2013-01-01

Gait disorders are common in multiple sclerosis (MS) and lead to a progressive reduction of function and quality of life. Test the effects of robot-assisted gait rehabilitation in MS subjects through a pilot randomized-controlled study. We enrolled MS subjects with Expanded Disability Status Scale scores within 4.5-6.5. The experimental group received 12 robot-assisted gait training sessions over 6 weeks. The control group received the same amount of conventional physiotherapy. Outcomes measures were both biomechanical assessment of gait, including kinematics and spatio-temporal parameters, and clinical test of walking endurance (six-minute walk test) and mobility (Up and Go Test). 16 subjects (n = 8 experimental group, n = 8 control group) were included in the final analysis. At baseline the two groups were similar in all variables, except for step length. Data showed walking endurance, as well as spatio-temporal gait parameters improvements after robot-assisted gait training. Pelvic antiversion and reduced hip extension during terminal stance ameliorated after aforementioned intervention. Robot-assisted gait training seems to be effective in increasing walking competency in MS subjects. Moreover, it could be helpful in restoring the kinematic of the hip and pelvis.

Human Walk Modeled by PCPG to Control a Lower Limb Neuroprosthesis by High-Level Commands

Directory of Open Access Journals (Sweden)

Matthieu Duvinage

2012-06-01

Full Text Available Current active leg prostheses do not integrate the most recent advances in Brain-Computer Interfaces (BCI and bipedal robotics. Moreover, their actuators are seldom driven by the subject’s intention. This paper aims at showing a summary of our current results in the field of human gait rehabilitation. In a first prototype, the main focus was on people suffering from foot drop problems, i.e. people who are unable to lift their feet. However, current work is focusing on a full active ankle orthosis. The approach is threefold: a BCI system, a gait model and an orthosis. Thanks to the BCI system, patients are able to generate high-level commands. Typically, a command could represent a speed modification. Then, a gait model based on a programmable central pattern generator is used to generate the adequate kinematics. Finally, the orthosis is tracking this kinematics when the foot is in the air, whereas, the orthosis is mimicking a spring when the foot is on the ground.

Design of a gait training device for control of pelvic obliquity.

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Pietrusinski, Maciej; Severini, Giacomo; Cajigas, Iahn; Mavroidis, Constantinos; Bonato, Paolo

2012-01-01

This paper presents the design and testing of a novel device for the control of pelvic obliquity during gait. The device, called the Robotic Gait Rehabilitation (RGR) Trainer, consists of a single actuator system designed to target secondary gait deviations, such as hip-hiking, affecting the movement of the pelvis. Secondary gait deviations affecting the pelvis are generated in response to primary gait deviations (e.g. limited knee flexion during the swing phase) in stroke survivors and contribute to the overall asymmetrical gait pattern often observed in these patients. The proposed device generates a force field able to affect the obliquity of the pelvis (i.e. the rotation of the pelvis around the anteroposterior axis) by using an impedance controlled single linear actuator acting on a hip orthosis. Tests showed that the RGR Trainer is able to induce changes in pelvic obliquity trajectories (hip-hiking) in healthy subjects. These results suggest that the RGR Trainer is suitable to test the hypothesis that has motivated our efforts toward developing the system, namely that addressing both primary and secondary gait deviations during robotic-assisted gait training may help promote a physiologically-sound gait behavior more effectively than when only primary deviations are addressed.

Hybrid gait training with an overground robot for people with incomplete spinal cord injury: a pilot study.

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Del-Ama, Antonio J; Gil-Agudo, Angel; Pons, José L; Moreno, Juan C

2014-01-01

Locomotor training has proved to provide beneficial effect in terms of mobility in incomplete paraplegic patients. Neuroprosthetic technology can contribute to increase the efficacy of a training paradigm in the promotion of a locomotor pattern. Robotic exoskeletons can be used to manage the unavoidable loss of performance of artificially driven muscles. Hybrid exoskeletons blend complementary robotic and neuro-prosthetic technologies. The aim of this pilot study was to determine the effects of hybrid gait training in three case studies with persons with incomplete spinal cord injury (iSCI) in terms of locomotion performance during assisted gait, patient-robot adaptations, impact on ambulation and assessment of lower limb muscle strength and spasticity. Participants with iSCI received interventions with a hybrid bilateral exoskeleton for 4 days. Assessment of gait function revealed that patients improved the 6 min and 10 m walking tests after the intervention, and further improvements were observed 1 week after the intervention. Muscle examination revealed improvements in knee and hip sagittal muscle balance scores and decreased score in ankle extensor balance. It is concluded that improvements in biomechanical function of the knee joint after the tested overground hybrid gait trainer are coherent with improvements in gait performance.

Task-specific ankle robotics gait training after stroke: a randomized pilot study.

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Forrester, Larry W; Roy, Anindo; Hafer-Macko, Charlene; Krebs, Hermano I; Macko, Richard F

2016-06-02

An unsettled question in the use of robotics for post-stroke gait rehabilitation is whether task-specific locomotor training is more effective than targeting individual joint impairments to improve walking function. The paretic ankle is implicated in gait instability and fall risk, but is difficult to therapeutically isolate and refractory to recovery. We hypothesize that in chronic stroke, treadmill-integrated ankle robotics training is more effective to improve gait function than robotics focused on paretic ankle impairments. Participants with chronic hemiparetic gait were randomized to either six weeks of treadmill-integrated ankle robotics (n = 14) or dose-matched seated ankle robotics (n = 12) videogame training. Selected gait measures were collected at baseline, post-training, and six-week retention. Friedman, and Wilcoxon Sign Rank and Fisher's exact tests evaluated within and between group differences across time, respectively. Six weeks post-training, treadmill robotics proved more effective than seated robotics to increase walking velocity, paretic single support, paretic push-off impulse, and active dorsiflexion range of motion. Treadmill robotics durably improved gait dorsiflexion swing angle leading 6/7 initially requiring ankle braces to self-discarded them, while their unassisted paretic heel-first contacts increased from 44 % to 99.6 %, versus no change in assistive device usage (0/9) following seated robotics. Treadmill-integrated, but not seated ankle robotics training, durably improves gait biomechanics, reversing foot drop, restoring walking propulsion, and establishing safer foot landing in chronic stroke that may reduce reliance on assistive devices. These findings support a task-specific approach integrating adaptive ankle robotics with locomotor training to optimize mobility recovery. NCT01337960. https://clinicaltrials.gov/ct2/show/NCT01337960?term=NCT01337960&rank=1.

An ankle-foot orthosis powered by artificial pneumatic muscles.

Science.gov (United States)

Ferris, Daniel P; Czerniecki, Joseph M; Hannaford, Blake

2005-05-01

We developed a pneumatically powered orthosis for the human ankle joint. The orthosis consisted of a carbon fiber shell, hinge joint, and two artificial pneumatic muscles. One artificial pneumatic muscle provided plantar flexion torque and the second one provided dorsiflexion torque. Computer software adjusted air pressure in each artificial muscle independently so that artificial muscle force was proportional to rectified low-pass-filtered electromyography (EMG) amplitude (i.e., proportional myoelectric control). Tibialis anterior EMG activated the artificial dorsiflexor and soleus EMG activated the artificial plantar flexor. We collected joint kinematic and artificial muscle force data as one healthy participant walked on a treadmill with the orthosis. Peak plantar flexor torque provided by the orthosis was 70 Nm, and peak dorsiflexor torque provided by the orthosis was 38 Nm. The orthosis could be useful for basic science studies on human locomotion or possibly for gait rehabilitation after neurological injury.

Hybrid gait training with an overground robot for people with incomplete spinal cord injury: a pilot study

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Antonio J del-Ama

2014-05-01

Full Text Available Locomotor training has proved to provide beneficial effect in terms of mobility in incomplete paraplegic patients. Neuroprosthetic technology can contribute to increase the efficacy of a training paradigm in the promotion of a locomotor pattern. Robotic exoskeletons can be used to manage the unavoidable loss of performance of artificially-driven muscles. Hybrid exoskeletons blend complementary robotic and neuro-prosthetic technologies. The aim of this pilot study was to determine the effects of hybrid gait training in three case studies with persons with incomplete spinal cord injury in terms of locomotion performance during assisted gait, patient-robot adaptations, impact on ambulation and assessment of lower limb muscle strength and spasticity. Participants with incomplete Spinal Cord Injury (SCI received interventions with a hybrid bilateral exoskeleton for 4 days. Assessment of gait function revealed that patients improved the 6 minutes and 10 meters walking tests after the intervention, and further improvements were observed one week after the intervention. Muscle examination revealed improvements in knee and hip sagittal muscle balance scores and decreased score in ankle extensor balance. It is concluded that improvements in biomechanical function of the knee joint after the tested overground hybrid gait trainer are coherent with improvements in gait performance.

Effect of pneumatic compressing powered orthosis in stroke patients: preliminary study.

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Kim, Eun Sil; Yoon, Yong-Soon; Sohn, Min Kyun; Kwak, Soo-Hyun; Choi, Jong Ho; Oh, Ji Sun

2015-04-01

To evaluate the feasibility and effectiveness of a knee-ankle-foot orthosis powered by artificial pneumatic muscles (PKAFO). Twenty-three hemiplegic patients (age, 59.6±13.7 years) were assessed 19.7±36.6 months after brain lesion. The 10-m walking time was measured as a gait parameter while the individual walked on a treadmill. Walking speed (m/s), step cycle (cycle/s), and step length (m) were also measured on a treadmill with and without PKAFO, and before and after gait training. Clinical parameters measured before and after gait training included Korean version of Modified Bathel Index (K-MBI), manual muscle test (MMT), and Modified Ashworth Scale (MAS) of hemiplegic ankle. Gait training comprised treadmill walking for 20 minutes, 5 days a week for 3 weeks at a comfortable speed. The 10-m walking time, walking speed, step length, and step cycle were significantly greater with PKAFO than without PKAFO, and after gait training (both p<0.05). K-MBI was improved after gait training (p<0.05), but MMT and MAS were not. PKAFO may improve gait function in hemiplegic patients. It can be a useful orthosis for gait training in hemiplegic patients.

A Robotic Exoskeleton for Treatment of Crouch Gait in Children With Cerebral Palsy: Design and Initial Application.

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Lerner, Zachary F; Damiano, Diane L; Park, Hyung-Soon; Gravunder, Andrew J; Bulea, Thomas C

2017-06-01

Crouch gait, a pathological pattern of walking characterized by excessive knee flexion, is one of the most common gait disorders observed in children with cerebral palsy (CP). Effective treatment of crouch during childhood is critical to maintain mobility into adulthood, yet current interventions do not adequately alleviate crouch in most individuals. Powered exoskeletons provide an untapped opportunity for intervention. The multiple contributors to crouch, including spasticity, contracture, muscle weakness, and poor motor control make design and control of such devices challenging in this population. To our knowledge, no evidence exists regarding the feasibility or efficacy of utilizing motorized assistance to alleviate knee flexion in crouch gait. Here, we present the design of and first results from a powered exoskeleton for extension assistance as a treatment for crouch gait in children with CP. Our exoskeleton, based on the architecture of a knee-ankle-foot orthosis, is lightweight (3.2 kg) and modular. On board sensors enable knee extension assistance to be provided during distinct phases of the gait cycle. We tested our device on one six-year-old male participant with spastic diplegia from CP. Our results show that the powered exoskeleton improved knee extension during stance by 18.1° while total knee range of motion improved 21.0°. Importantly, we observed no significant decrease in knee extensor muscle activity, indicating the user did not rely solely on the exoskeleton to extend the limb. These results establish the initial feasibility of robotic exoskeletons for treatment of crouch and provide impetus for continued investigation of these devices with the aim of deployment for long term gait training in this population.

Evaluating alternative gait strategies using evolutionary robotics.

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Sellers, William I; Dennis, Louise A; W -J, Wang; Crompton, Robin H

2004-05-01

Evolutionary robotics is a branch of artificial intelligence concerned with the automatic generation of autonomous robots. Usually the form of the robot is predefined and various computational techniques are used to control the machine's behaviour. One aspect is the spontaneous generation of walking in legged robots and this can be used to investigate the mechanical requirements for efficient walking in bipeds. This paper demonstrates a bipedal simulator that spontaneously generates walking and running gaits. The model can be customized to represent a range of hominoid morphologies and used to predict performance parameters such as preferred speed and metabolic energy cost. Because it does not require any motion capture data it is particularly suitable for investigating locomotion in fossil animals. The predictions for modern humans are highly accurate in terms of energy cost for a given speed and thus the values predicted for other bipeds are likely to be good estimates. To illustrate this the cost of transport is calculated for Australopithecus afarensis. The model allows the degree of maximum extension at the knee to be varied causing the model to adopt walking gaits varying from chimpanzee-like to human-like. The energy costs associated with these gait choices can thus be calculated and this information used to evaluate possible locomotor strategies in early hominids.

Effects on foot external rotation of the modified ankle-foot orthosis on post-stroke hemiparetic gait.

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Kim, Ha Jeong; Chun, Min Ho; Kim, Hong Min; Kim, Bo Ryun

2013-08-01

To evaluate the effects of heel-opened ankle foot orthosis (HOAFO) on hemiparetic gait after stroke, especially on external foot rotation, and to compare the effects of HOAFO with conventional plastic-AFO (pAFO) and barefoot during gait. This cross-over observational study involved 15 hemiparetic patients with external rotation of the affected foot. All subjects were able to walk independently, regardless of their usual use of a single cane, and had a less than fair-grade in ankle dorsiflexion power. Each patient was asked to walk in three conditions with randomized sequences: 1) barefoot, 2) with a pAFO, and 3) with an HOAFO. Their gait patterns were analyzed using a motion analysis system. Fifteen patients consisted of nine males and six females. On gait analysis, hip and foot external rotation were significantly greater in pAFO (-3.35° and -23.68°) than in barefoot and HOAFO conditions (pexternal rotation compared with pAFO; although there was no significant difference between HOAFO and barefoot walking. Walking speed and percentage of single limb support were significantly greater for HOAFO than in barefoot walking. HOAFO was superior to pAFO in reducing hip and foot external rotation during the stance phase in patients with post-stroke hemiparesis. HOAFO may, therefore, be useful in patients with excessive external rotation of the foot during conventional pAFO.

Fuzzy logic controller for stabilization of biped robot gait

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Ryadchikov I.V.

2018-01-01

Full Text Available The article centers round the problem of stabilization of biped robot gait through smoothing out the jumps of first and second order derivatives of a biped robot control vector using the fuzzy logic approach. The structure of a composite Takagi-Sugeno fuzzy logic controller developed by the authors is presented. The simulation study of a robot gait with climbing an obstacle is carried out and the results provided in the article showed that the developed controller performed significantly better than the analytical formula model in terms of smoothing out the derivatives of the control vector.

Motor Imagery-Based Brain-Computer Interface Coupled to a Robotic Hand Orthosis Aimed for Neurorehabilitation of Stroke Patients

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Jessica Cantillo-Negrete

2018-01-01

Full Text Available Motor imagery-based brain-computer interfaces (BCI have shown potential for the rehabilitation of stroke patients; however, low performance has restricted their application in clinical environments. Therefore, this work presents the implementation of a BCI system, coupled to a robotic hand orthosis and driven by hand motor imagery of healthy subjects and the paralysed hand of stroke patients. A novel processing stage was designed using a bank of temporal filters, the common spatial pattern algorithm for feature extraction and particle swarm optimisation for feature selection. Offline tests were performed for testing the proposed processing stage, and results were compared with those computed with common spatial patterns. Afterwards, online tests with healthy subjects were performed in which the orthosis was activated by the system. Stroke patients’ average performance was 74.1 ± 11%. For 4 out of 6 patients, the proposed method showed a statistically significant higher performance than the common spatial pattern method. Healthy subjects’ average offline and online performances were of 76.2 ± 7.6% and 70 ± 6.7, respectively. For 3 out of 8 healthy subjects, the proposed method showed a statistically significant higher performance than the common spatial pattern method. System’s performance showed that it has a potential to be used for hand rehabilitation of stroke patients.

Design and evaluation of Mina: a robotic orthosis for paraplegics.

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Neuhaus, Peter D; Noorden, Jerryll H; Craig, Travis J; Torres, Tecalote; Kirschbaum, Justin; Pratt, Jerry E

2011-01-01

Mobility options for persons suffering from paraplegia or paraparesis are limited to mainly wheeled devices. There are significant health, psychological, and social consequences related to being confined to a wheelchair. We present the Mina, a robotic orthosis for assisting mobility, which offers a legged mobility option for these persons. Mina is an overground robotic device that is worn on the back and around the legs to provide mobility assistance for people suffering from paraplegia or paraparesis. Mina uses compliant actuation to power the hip and knee joints. For paralyzed users, balance is provided with the assistance of forearm crutches. This paper presents the evaluation of Mina with two paraplegics (SCI ASIA-A). We confirmed that with a few hours of training and practice, Mina is currently able to provide paraplegics walking mobility at speeds of up to 0.20 m/s. We further confirmed that using Mina is not physically taxing and requires little cognitive effort, allowing the user to converse and maintain eye contact while walking. © 2011 IEEE

Weight transfer analysis in adults with hemiplegia using ankle foot orthosis.

Science.gov (United States)

Nolan, Karen J; Yarossi, Mathew

2011-03-01

Identifying and understanding the changes in transfer of momentum that are directly affected by orthotic intervention are significant factors related to the improvement of mobility in individuals with hemiplegia. The purpose of this investigation was to use a novel analysis technique to objectively measure weight transfer during double support (DS) in healthy individuals and individuals with hemiplegia secondary to stroke with and without an ankle foot orthosis. Prospective, Repeated measures, case-controlled trial. Participants included 25 adults with stroke-related hemiplegia >6 months using a prescribed ankle foot orthosis and 12 age-matched healthy controls. Main outcome measures included the weight transfer point timing (WTP, %DS), maximum total force timing (MTF, %DS), timing difference between WTP and MTF (MTF-WTP, %DS) and the linearity of loading (LOL, R(2)) during the DS phase of the gait cycle. The WTP and LOL were significantly different between conditions with and without the ankle foot orthosis for the affected and unaffected limb in post-stroke individuals, p ≤ 0.01. The MTF and difference in timing between MTF-WTP were significantly different during affected limb loading with and without the ankle foot orthosis in the stroke group, p ≤ 0.0001 and p = 0.03, respectively. MTF, MTF-WTP and LOL were significantly different between individuals with stroke (during affected limb loading) and healthy controls (during right limb loading). This research established a systematic method for analysing weight transfer during walking to evaluate the effect of an ankle foot orthosis on loading during double support in hemiplegic gait. This novel method can be used to elucidate biomechanical mechanisms behind orthosis-mediated changes in gait patterns and quantify functional mobility outcomes in rehabilitation. This novel approach to orthotic assessment will provide the clinician with needed objective evidence to select the most effective orthotic

A study of the passive gait of a compass-like biped robot: Symmetry and chaos

International Nuclear Information System (INIS)

Goswami, A.; Espiau, B.; Thuilot, B.

1998-01-01

The focus of this work is a systematic study of the passive gait of a compass-like planar, biped robot on inclined slopes. The robot is kinematically equivalent to a double pendulum, possessing two kneeless legs with point masses and a third point mass at the hip joint. Three parameters, namely, the ground-slope angle and the normalized mass and length of the robot describe its gait. The authors show that in response to a continuous change in any one of its parameters, the symmetric and steady stable gait of the unpowered robot gradually evolves through a regime of bifurcations characterized by progressively complicated asymmetric gaits, eventually arriving at an apparently chaotic gait where not two steps are identical. The robot can maintain this gait indefinitely. A necessary (but not sufficient) condition for the stability of such gaits is the contraction of the phase-fluid volume. For this frictionless robot, the volume contraction, which the authors compute, is caused by the dissipative effects of the ground-impact model. In the chaotic regime, the fractal dimension of the robot's strange attractor (2.07) compared to its state-space dimension (4) also reveals strong contraction. The authors present a novel graphical technique based on the first return map that compactly captures the entire evolution of the gait, from symmetry to chaos. Additional passive dissipative elements in the robot joint results in a significant improvement in the stability and the versatility of the gait, and provide a rich repertoire for simple controls laws

Serpentine Robot Model and Gait Design Using Autodesk Inventor and Simulink SimMechanics

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Daniel; Iman Alamsyah, Mohammad; Erwin; Tan, Sofyan

2014-03-01

The authors introduce gaits of a serpentine robot with linear expansion mechanism where the robot varies its length using joints with three degrees of freedom. The 3D model of the serpentine robot is drawed in Autocad Inventor® and exported to SimMechanics® for straighforward modeling of the kinematics. The gaits are important for robots designed to explore ruins of disasters where the working spaces are very tight. For maximum flexibility of the serpentine robot, we adopted a joint design with three parallel actuators, where the joint is capable of linear movement in the forward axis, and rotational movements around two other axes. The designed linear expansion gaits is calculated for forward movement when the robot is posing straight or turning laterally.

Serpentine Robot Model and Gait Design Using Autodesk Inventor and Simulink SimMechanics

Directory of Open Access Journals (Sweden)

Daniel

2014-03-01

Full Text Available The authors introduce gaits of a serpentine robot with linear expansion mechanism where the robot varies its length using joints with three degrees of freedom. The 3D model of the serpentine robot is drawed in Autocad Inventor® and exported to SimMechanics® for straighforward modeling of the kinematics. The gaits are important for robots designed to explore ruins of disasters where the working spaces are very tight. For maximum flexibility of the serpentine robot, we adopted a joint design with three parallel actuators, where the joint is capable of linear movement in the forward axis, and rotational movements around two other axes. The designed linear expansion gaits is calculated for forward movement when the robot is posing straight or turning laterally.

Robot-assisted gait training versus treadmill training in patients with Parkinson's disease: a kinematic evaluation with gait profile score.

Science.gov (United States)

Galli, M; Cimolin, V; De Pandis, M F; Le Pera, D; Sova, I; Albertini, G; Stocchi, F; Franceschini, M

2016-01-01

The purpose of this study was to quantitatively compare the effects, on walking performance, of end-effector robotic rehabilitation locomotor training versus intensive training with a treadmill in Parkinson's disease (PD). Fifty patients with PD were randomly divided into two groups: 25 were assigned to the robot-assisted therapy group (RG) and 25 to the intensive treadmill therapy group (IG). They were evaluated with clinical examination and 3D quantitative gait analysis [gait profile score (GPS) and its constituent gait variable scores (GVSs) were calculated from gait analysis data] at the beginning (T0) and at the end (T1) of the treatment. In the RG no differences were found in the GPS, but there were significant improvements in some GVSs (Pelvic Obl and Hip Ab-Add). The IG showed no statistically significant changes in either GPS or GVSs. The end-effector robotic rehabilitation locomotor training improved gait kinematics and seems to be effective for rehabilitation in patients with mild PD.

Turtle mimetic soft robot with two swimming gaits.

Science.gov (United States)

Song, Sung-Hyuk; Kim, Min-Soo; Rodrigue, Hugo; Lee, Jang-Yeob; Shim, Jae-Eul; Kim, Min-Cheol; Chu, Won-Shik; Ahn, Sung-Hoon

2016-05-04

This paper presents a biomimetic turtle flipper actuator consisting of a shape memory alloy composite structure for implementation in a turtle-inspired autonomous underwater vehicle. Based on the analysis of the Chelonia mydas, the flipper actuator was divided into three segments containing a scaffold structure fabricated using a 3D printer. According to the filament stacking sequence of the scaffold structure in the actuator, different actuating motions can be realized and three different types of scaffold structures were proposed to replicate the motion of the different segments of the flipper of the Chelonia mydas. This flipper actuator can mimic the continuous deformation of the forelimb of Chelonia mydas which could not be realized in previous motor based robot. This actuator can also produce two distinct motions that correspond to the two different swimming gaits of the Chelonia mydas, which are the routine and vigorous swimming gaits, by changing the applied current sequence of the SMA wires embedded in the flipper actuator. The generated thrust and the swimming efficiency in each swimming gait of the flipper actuator were measured and the results show that the vigorous gait has a higher thrust but a relatively lower swimming efficiency than the routine gait. The flipper actuator was implemented in a biomimetic turtle robot, and its average swimming speed in the routine and vigorous gaits were measured with the vigorous gait being capable of reaching a maximum speed of 11.5 mm s(-1).

Robot-assisted gait training for stroke patients: current state of the art and perspectives of robotics.

Science.gov (United States)

Morone, Giovanni; Paolucci, Stefano; Cherubini, Andrea; De Angelis, Domenico; Venturiero, Vincenzo; Coiro, Paola; Iosa, Marco

2017-01-01

In this review, we give a brief outline of robot-mediated gait training for stroke patients, as an important emerging field in rehabilitation. Technological innovations are allowing rehabilitation to move toward more integrated processes, with improved efficiency and less long-term impairments. In particular, robot-mediated neurorehabilitation is a rapidly advancing field, which uses robotic systems to define new methods for treating neurological injuries, especially stroke. The use of robots in gait training can enhance rehabilitation, but it needs to be used according to well-defined neuroscientific principles. The field of robot-mediated neurorehabilitation brings challenges to both bioengineering and clinical practice. This article reviews the state of the art (including commercially available systems) and perspectives of robotics in poststroke rehabilitation for walking recovery. A critical revision, including the problems at stake regarding robotic clinical use, is also presented.

MotionTherapy@Home - First results of a clinical study with a novel robotic device for automated locomotion therapy at home.

Science.gov (United States)

Rupp, Rüdiger; Plewa, Harry; Schuld, Christian; Gerner, Hans Jürgen; Hofer, Eberhard P; Knestel, Markus

2011-02-01

In incomplete spinal cord injured subjects, task-oriented training regimes are applied for enhancement of neuroplasticity to improve gait capacity. However, a sufficient training intensity can only be achieved during the inpatient phase, which is getting shorter and shorter due to economic restrictions. In the clinical environment, complex and expensive robotic devices have been introduced to maintain the duration and the intensity of the training, but up to now only a few exist for continuation of automated locomotion training at home. For continuation of the automated locomotion training at home prototypes of the compact, pneumatically driven orthosis MoreGait have been realized, which generate the key afferent stimuli for activation of the spinal gait pattern generator. Artificial pneumatic muscles with excellent weight-to-force ratio and safety characteristics have been integrated as joint actuators. Additionally, a Stimulative Shoe for generation of the appropriate foot loading pattern has been developed without the need for verticalization of the user. The first results of the pilot study in eight chronic incomplete spinal cord injured subjects indicate that the home-based therapy is safe and feasible. The therapy related improvements of the walking capacity are in the range of locomotion robots used in clinical settings.

Neuromorphic walking gait control.

Science.gov (United States)

Still, Susanne; Hepp, Klaus; Douglas, Rodney J

2006-03-01

We present a neuromorphic pattern generator for controlling the walking gaits of four-legged robots which is inspired by central pattern generators found in the nervous system and which is implemented as a very large scale integrated (VLSI) chip. The chip contains oscillator circuits that mimic the output of motor neurons in a strongly simplified way. We show that four coupled oscillators can produce rhythmic patterns with phase relationships that are appropriate to generate all four-legged animal walking gaits. These phase relationships together with frequency and duty cycle of the oscillators determine the walking behavior of a robot driven by the chip, and they depend on a small set of stationary bias voltages. We give analytic expressions for these dependencies. This chip reduces the complex, dynamic inter-leg control problem associated with walking gait generation to the problem of setting a few stationary parameters. It provides a compact and low power solution for walking gait control in robots.

Fully embedded myoelectric control for a wearable robotic hand orthosis.

Science.gov (United States)

Ryser, Franziska; Butzer, Tobias; Held, Jeremia P; Lambercy, Olivier; Gassert, Roger

2017-07-01

To prevent learned non-use of the affected hand in chronic stroke survivors, rehabilitative training should be continued after discharge from the hospital. Robotic hand orthoses are a promising approach for home rehabilitation. When combined with intuitive control based on electromyography, the therapy outcome can be improved. However, such systems often require extensive cabling, experience in electrode placement and connection to external computers. This paper presents the framework for a stand-alone, fully wearable and real-time myoelectric intention detection system based on the Myo armband. The hard and software for real-time gesture classification were developed and combined with a routine to train and customize the classifier, leading to a unique ease of use. The system including training of the classifier can be set up within less than one minute. Results demonstrated that: (1) the proposed algorithm can classify five gestures with an accuracy of 98%, (2) the final system can online classify three gestures with an accuracy of 94.3% and, in a preliminary test, (3) classify three gestures from data acquired from mildly to severely impaired stroke survivors with an accuracy of over 78.8%. These results highlight the potential of the presented system for electromyography-based intention detection for stroke survivors and, with the integration of the system into a robotic hand orthosis, the potential for a wearable platform for all day robot-assisted home rehabilitation.

Physical human-robot interaction of an active pelvis orthosis: toward ergonomic assessment of wearable robots.

Science.gov (United States)

d'Elia, Nicolò; Vanetti, Federica; Cempini, Marco; Pasquini, Guido; Parri, Andrea; Rabuffetti, Marco; Ferrarin, Maurizio; Molino Lova, Raffaele; Vitiello, Nicola

2017-04-14

In human-centered robotics, exoskeletons are becoming relevant for addressing needs in the healthcare and industrial domains. Owing to their close interaction with the user, the safety and ergonomics of these systems are critical design features that require systematic evaluation methodologies. Proper transfer of mechanical power requires optimal tuning of the kinematic coupling between the robotic and anatomical joint rotation axes. We present the methods and results of an experimental evaluation of the physical interaction with an active pelvis orthosis (APO). This device was designed to effectively assist in hip flexion-extension during locomotion with a minimum impact on the physiological human kinematics, owing to a set of passive degrees of freedom for self-alignment of the human and robotic hip flexion-extension axes. Five healthy volunteers walked on a treadmill at different speeds without and with the APO under different levels of assistance. The user-APO physical interaction was evaluated in terms of: (i) the deviation of human lower-limb joint kinematics when wearing the APO with respect to the physiological behavior (i.e., without the APO); (ii) relative displacements between the APO orthotic shells and the corresponding body segments; and (iii) the discrepancy between the kinematics of the APO and the wearer's hip joints. The results show: (i) negligible interference of the APO in human kinematics under all the experimented conditions; (ii) small (i.e., ergonomics assessment of wearable robots.

The effect of ankle foot orthosis stiffness on the energy cost of walking: a simulation study.

Science.gov (United States)

Bregman, D J J; van der Krogt, M M; de Groot, V; Harlaar, J; Wisse, M; Collins, S H

2011-11-01

In stroke and multiple sclerosis patients, gait is frequently hampered by a reduced ability to push-off with the ankle caused by weakness of the plantar-flexor muscles. To enhance ankle push-off and to decrease the high energy cost of walking, spring-like carbon-composite Ankle Foot Orthoses are frequently prescribed. However, it is unknown what Ankle Foot Orthoses stiffness should be used to obtain the most efficient gait. The aim of this simulation study was to gain insights into the effect of variation in Ankle Foot Orthosis stiffness on the amount of energy stored in the Ankle Foot Orthosis and the energy cost of walking. We developed a two-dimensional forward-dynamic walking model with a passive spring at the ankle representing the Ankle Foot Orthosis and two constant torques at the hip for propulsion. We varied Ankle Foot Orthosis stiffness while keeping speed and step length constant. We found an optimal stiffness, at which the energy delivered at the hip joint was minimal. Energy cost decreased with increasing energy storage in the ankle foot orthosis, but the most efficient gait did not occur with maximal energy storage. With maximum storage, push-off occurred too late to reduce the impact of the contralateral leg with the floor. Maximum return prior to foot strike was also suboptimal, as push-off occurred too early and its effects were subsequently counteracted by gravity. The optimal Ankle Foot Orthosis stiffness resulted in significant push-off timed just prior to foot strike and led to greater ankle plantar-flexion velocity just before contralateral foot strike. Our results suggest that patient energy cost might be reduced by the proper choice of Ankle Foot Orthosis stiffness. Copyright © 2011 Elsevier Ltd. All rights reserved.

FY1995 development of rehabilitation system for promoting social integration of people with disabilities. Development of a robotic orthosis assisting motion capabilities; 1995 nendo shogaino aru hito no shakai shinshutsu wo sokushinsuru rehabilitation system no kaihatsu. Rehabilitation kino wo yusuru doryoku sogu no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

People with slight disabilities on motion. capability can be active in daily life using properly designed motion-assisting devices. Using these device in various cases would help the disabled participate in production activities, and would promote social integration of the disabled as rehabilitation in a broad sense. This research aims at developing such a device capable to help human motion by forearm based on technology and science in robotics. Two different methods are discussed in this research in order to develop robotic orthosis with good performance for assisting human motion by forearm. The first method is constructing a robotic orthosis with electronic motors and force sensors to produce a desired mechanical impedance. This orthosis was carefully designed such that mechanical safety for human is realized. The validity of the mechanism is illustrated by several experiments. The second method is constructing a low cost robotic orthosis with pneumatic actuators. A new type of pneumatic actuator is developed to realize this orthosis. Experimental results show that physical therapy can be performed effectively using this orthosis operated by direct teaching. (NEDO)

Ankle foot orthosis-footwear combination tuning: an investigation into common clinical practice in the United Kingdom.

Science.gov (United States)

Eddison, Nicola; Chockalingam, Nachiappan; Osborne, Stephen

2015-04-01

Ankle foot orthoses are used to treat a wide variety of gait pathologies. Ankle foot orthosis-footwear combination tuning should be routine clinical practice when prescribing an ankle foot orthosis. Current research suggests that failure to tune ankle foot orthosis-footwear combinations can lead to immediate detrimental effect on function, and in the longer term, it may actually contribute to deterioration. The purpose of this preliminary study was to identify the current level of knowledge clinicians have in the United Kingdom regarding ankle foot orthosis-footwear combination tuning and to investigate common clinical practice regarding ankle foot orthosis-footwear combination tuning among UK orthotists. Cross-sectional survey. A prospective study employing a multi-item questionnaire was sent out to registered orthotists and uploaded on to the official website of British Association of Prosthetists and Orthotists to be accessed by their members. A total of 41 completed questionnaires were received. The results demonstrate that only 50% of participants use ankle foot orthosis-footwear combination tuning as standard clinical practice. The most prevalent factors preventing participants from carrying out ankle foot orthosis-footwear combination tuning are a lack of access to three-dimensional gait analysis equipment (37%) and a lack of time available in their clinics (27%). Although, ankle foot orthosis-footwear combination tuning has been identified as an essential aspect of the prescription of ankle foot orthoses, the results of this study show a lack of understanding of the key principles behind ankle foot orthosis-footwear combination tuning. © The International Society for Prosthetics and Orthotics 2014.

Gait COP trajectory of left side hip-dislocation and scoliotic patient using ankle-foot orthoses

Science.gov (United States)

Chong, Albert K.; Alrikabi, Redha; Milburn, Peter

2017-07-01

Plantar pressure-sensing mats and insole plantar sensor pads are ideal low-cost alternatives to force plates for capturing plantar COP excursion during gait. The acquired COP traces, in the form of pedobarographic images are favored by many clinicians and allied health professionals for evaluation of foot loading and balance in relation to foot biomechanics, foot injury, foot deformation, and foot ulceration. Researchers have recommended the use of COP trace for the biomechanical study of the deformed foot and lower-limb to improve orthosis design and testing. A correctly designed orthoses improves mobility and reduces pain in the foot, lower limb and lower spine region during gait. The research was carried out to evaluate the performance of two types of orthosis, namely: a custom-molded orthosis and an over-the-counter molded orthosis to determine the quality of gait of an adult scoliotic patient. COP trace patterns were compared with those of a healthy adult and showed the design of the custom-molded orthosis resulted in an improved quality of movements and provided enhanced stability for the deformed left foot during gait.

Robot-assisted gait training versus treadmill training in patients with Parkinson’s disease: a kinematic evaluation with gait profile score

Science.gov (United States)

Galli, Manuela; Cimolin, Veronica; De Pandis, Maria Francesca; Le Pera, Domenica; Sova, Ivan; Albertini, Giorgio; Stocchi, Fabrizio; Franceschini, Marco

2016-01-01

Summary The purpose of this study was to quantitatively compare the effects, on walking performance, of end-effector robotic rehabilitation locomotor training versus intensive training with a treadmill in Parkinson’s disease (PD). Fifty patients with PD were randomly divided into two groups: 25 were assigned to the robot-assisted therapy group (RG) and 25 to the intensive treadmill therapy group (IG). They were evaluated with clinical examination and 3D quantitative gait analysis [gait profile score (GPS) and its constituent gait variable scores (GVSs) were calculated from gait analysis data] at the beginning (T0) and at the end (T1) of the treatment. In the RG no differences were found in the GPS, but there were significant improvements in some GVSs (Pelvic Obl and Hip Ab-Add). The IG showed no statistically significant changes in either GPS or GVSs. The end-effector robotic rehabilitation locomotor training improved gait kinematics and seems to be effective for rehabilitation in patients with mild PD. PMID:27678210

Robotic Pectoral Fin Thrust Vectoring Using Weighted Gait Combinations

Directory of Open Access Journals (Sweden)

John S. Palmisano

2012-01-01

Full Text Available A method was devised to vector propulsion of a robotic pectoral fin by means of actively controlling fin surface curvature. Separate flapping fin gaits were designed to maximize thrust for each of three different thrust vectors: forward, reverse, and lift. By using weighted combinations of these three pre-determined main gaits, new intermediate hybrid gaits for any desired propulsion vector can be created with smooth transitioning between these gaits. This weighted gait combination (WGC method is applicable to other difficult-to-model actuators. Both 3D unsteady computational fluid dynamics (CFD and experimental results are presented.

Effects of ankle-foot orthoses on mediolateral foot-placement ability during post-stroke gait.

Science.gov (United States)

Zissimopoulos, Angelika; Fatone, Stefania; Gard, Steven

2015-10-01

Accurate and precise mediolateral foot placement is important for balance during gait, but is impaired post stroke. Mediolateral foot placement may be improved with ankle-foot orthosis use. The purpose of this study was to determine whether an ankle-foot orthosis improves mediolateral foot-placement ability during post-stroke ambulation. Crossover trial with randomized order of conditions tested. The accuracy and precision of mediolateral foot placement was quantified while subjects targeted four different randomized step widths. Subjects were tested with and without their regular non-rigid ankle-foot orthosis in two separate visits (order randomized). While ankle-foot orthosis use corrected foot and ankle alignment (i.e. significantly decreased mid-swing plantar flexion, p = 0.000), effects of ankle-foot orthosis use on hip hiking (p = 0.545), circumduction (p = 0.179), coronal plane hip range of motion (p = 0.06), and mediolateral foot-placement ability (p = 0.537) were not significant. While ankle-foot orthosis-mediated equinovarus correction of the affected foot and ankle was not associated with improved biomechanics of walking (i.e. proximal ipsilateral hip kinematics or mediolateral foot-placement ability), it may affect other aspects of balance that were not tested in this study (e.g. proprioception, cerebellar, vestibular, and cognitive mechanisms). Studies that investigate the effect of ankle-foot orthosis on gait can help advance stroke rehabilitation by documenting the specific gait benefits of ankle-foot orthosis use. In this study, we investigated the effect of ankle-foot orthosis use on mediolateral foot-placement ability, an aspect of gait important for maintaining balance. © The International Society for Prosthetics and Orthotics 2014.

Powered robotic exoskeletons in post-stroke rehabilitation of gait: a scoping review.

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Louie, Dennis R; Eng, Janice J

2016-06-08

Powered robotic exoskeletons are a potential intervention for gait rehabilitation in stroke to enable repetitive walking practice to maximize neural recovery. As this is a relatively new technology for stroke, a scoping review can help guide current research and propose recommendations for advancing the research development. The aim of this scoping review was to map the current literature surrounding the use of robotic exoskeletons for gait rehabilitation in adults post-stroke. Five databases (Pubmed, OVID MEDLINE, CINAHL, Embase, Cochrane Central Register of Clinical Trials) were searched for articles from inception to October 2015. Reference lists of included articles were reviewed to identify additional studies. Articles were included if they utilized a robotic exoskeleton as a gait training intervention for adult stroke survivors and reported walking outcome measures. Of 441 records identified, 11 studies, all published within the last five years, involving 216 participants met the inclusion criteria. The study designs ranged from pre-post clinical studies (n = 7) to controlled trials (n = 4); five of the studies utilized a robotic exoskeleton device unilaterally, while six used a bilateral design. Participants ranged from sub-acute (6 months) stroke. Training periods ranged from single-session to 8-week interventions. Main walking outcome measures were gait speed, Timed Up and Go, 6-min Walk Test, and the Functional Ambulation Category. Meaningful improvement with exoskeleton-based gait training was more apparent in sub-acute stroke compared to chronic stroke. Two of the four controlled trials showed no greater improvement in any walking outcomes compared to a control group in chronic stroke. In conclusion, clinical trials demonstrate that powered robotic exoskeletons can be used safely as a gait training intervention for stroke. Preliminary findings suggest that exoskeletal gait training is equivalent to traditional therapy for chronic stroke

Adaptive Strategy for Online Gait Learning Evaluated on the Polymorphic Robotic LocoKit

DEFF Research Database (Denmark)

Christensen, David Johan; Larsen, Jørgen Christian; Stoy, Kasper

2012-01-01

This paper presents experiments with a morphologyindependent, life-long strategy for online learning of locomotion gaits, performed on a quadruped robot constructed from the LocoKit modular robot. The learning strategy applies a stochastic optimization algorithm to optimize eight open parameters...... of a central pattern generator based gait implementation. We observe that the strategy converges in roughly ten minutes to gaits of similar or higher velocity than a manually designed gait and that the strategy readapts in the event of failed actuators. In future work we plan to study co-learning...

Control strategies for effective robot assisted gait rehabilitation: the state of art and future prospects.

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Cao, Jinghui; Xie, Sheng Quan; Das, Raj; Zhu, Guo L

2014-12-01

A large number of gait rehabilitation robots, together with a variety of control strategies, have been developed and evaluated during the last decade. Initially, control strategies applied to rehabilitation robots were adapted from those applied to traditional industrial robots. However, these strategies cannot optimise effectiveness of gait rehabilitation. As a result, researchers have been investigating control strategies tailored for the needs of rehabilitation. Among these control strategies, assisted-as-needed (AAN) control is one of the most popular research topics in this field. AAN training strategies have gained the theoretical and practical evidence based backup from motor learning principles and clinical studies. Various approaches to AAN training have been proposed and investigated by research groups all around the world. This article presents a review on control algorithms of gait rehabilitation robots to summarise related knowledge and investigate potential trends of development. There are existing review papers on control strategies of rehabilitation robots. The review by Marchal-Crespo and Reinkensmeyer (2009) had a broad cover of control strategies of all kinds of rehabilitation robots. Hussain et al. (2011) had specifically focused on treadmill gait training robots and covered a limited number of control implementations on them. This review article encompasses more detailed information on control strategies for robot assisted gait rehabilitation, but is not limited to treadmill based training. It also investigates the potential to further develop assist-as-needed gait training based on assessments of patients' ability. In this paper, control strategies are generally divided into the trajectory tracking control and AAN control. The review covers these two basic categories, as well as other control algorithm and technologies derived from them, such as biofeedback control. Assessments on human gait ability are also included to investigate how to

Continuous Static Gait with Twisting Trunk of a Metamorphic Quadruped Robot

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C. Zhang

2018-01-01

Full Text Available The natural quadrupeds, such as geckos and lizards, often twist their trunks when moving. Conventional quadruped robots cannot perform the same motion due to equipping with a trunk which is a rigid body or at most consists of two blocks connected by passive joints. This paper proposes a metamorphic quadruped robot with a reconfigurable trunk which can implement active trunk motions, called MetaRobot I. The robot can imitate the natural quadrupeds to execute motion of trunk twisting. Benefiting from the twisting trunk, the stride length of this quadruped is increased comparing to that of conventional quadruped robots.In this paper a continuous static gait benefited from the twisting trunk performing the increased stride length is introduced. After that, the increased stride length relative to the trunk twisting will be analysed mathematically. Other points impacting the implementation of the increased stride length in the gait are investigated such as the upper limit of the stride length and the kinematic margin. The increased stride length in the gait will lead the increase of locomotion speed comparing with conventional quadruped robots, giving the extent that natural quadrupeds twisting their trunks when moving. The simulation and an experiment on the prototype are then carried out to illustrate the benefits on the stride length and locomotion speed brought by the twisting trunk to the quadruped robot.

Detection of Gait Modes Using an Artificial Neural Network during Walking with a Powered Ankle-Foot Orthosis

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2016-01-01

This paper presents an algorithm, for use with a Portable Powered Ankle-Foot Orthosis (i.e., PPAFO) that can automatically detect changes in gait modes (level ground, ascent and descent of stairs or ramps), thus allowing for appropriate ankle actuation control during swing phase. An artificial neural network (ANN) algorithm used input signals from an inertial measurement unit and foot switches, that is, vertical velocity and segment angle of the foot. Output from the ANN was filtered and adjusted to generate a final data set used to classify different gait modes. Five healthy male subjects walked with the PPAFO on the right leg for two test scenarios (walking over level ground and up and down stairs or a ramp; three trials per scenario). Success rate was quantified by the number of correctly classified steps with respect to the total number of steps. The results indicated that the proposed algorithm's success rate was high (99.3%, 100%, and 98.3% for level, ascent, and descent modes in the stairs scenario, respectively; 98.9%, 97.8%, and 100% in the ramp scenario). The proposed algorithm continuously detected each step's gait mode with faster timing and higher accuracy compared to a previous algorithm that used a decision tree based on maximizing the reliability of the mode recognition. PMID:28070188

Design and Development of Effective Transmission Mechanisms on a Tendon Driven Hand Orthosis for Stroke Patients

OpenAIRE

Park, Sangwoo; Weber, Lynne; Bishop, Lauri; Stein, Joel; Ciocarlie, Matei

2018-01-01

Tendon-driven hand orthoses have advantages over exoskeletons with respect to wearability and safety because of their low-profile design and ability to fit a range of patients without requiring custom joint alignment. However, no existing study on a wearable tendon-driven hand orthosis for stroke patients presents evidence that such devices can overcome spasticity given repeated use and fatigue, or discusses transmission efficiency. In this study, we propose two designs that provide effective...

The physiological cost index of walking with a powered knee-ankle-foot orthosis in subjects with poliomyelitis: A pilot study.

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Arazpour, Mokhtar; Ahmadi Bani, Monireh; Samadian, Mohammad; Mousavi, Mohammad E; Hutchins, Stephen W; Bahramizadeh, Mahmood; Curran, Sarah; Mardani, Mohammad A

2016-08-01

A powered knee-ankle-foot orthosis was developed to provide restriction of knee flexion during stance phase and active flexion and extension of the knee during swing phase of gait. The purpose of this study was to determine its effect on the physiological cost index, walking speed and the distance walked in people with poliomyelitis compared to when walking with a knee-ankle-foot orthosis with drop lock knee joints. Quasi experimental study. Seven subjects with poliomyelitis volunteered for the study and undertook gait analysis with both types of knee-ankle-foot orthosis. Walking with the powered knee-ankle-foot orthosis significantly reduced walking speed (p = 0.015) and the distance walked (p = 0.004), and also, it did not improve physiological cost index values (p = 0.009) compared to walking with the locked knee-ankle-foot orthosis. Using a powered knee-ankle-foot orthosis did not significantly improve any of the primary outcome measures during walking for poliomyelitis subjects. This powered knee-ankle-foot orthosis design did not improve the physiological cost index of walking for people with poliomyelitis when compared to walking with a knee-ankle-foot orthosis with drop lock knee joints. This may have been due to the short training period used or the bulky design and additional weight of the powered orthosis. Further research is therefore warranted. © The International Society for Prosthetics and Orthotics 2015.

Robot-assisted gait training for stroke patients: current state of the art and perspectives of robotics

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Morone G

2017-05-01

Full Text Available Giovanni Morone,1,2 Stefano Paolucci,1,2 Andrea Cherubini,3 Domenico De Angelis,1 Vincenzo Venturiero,1 Paola Coiro,1 Marco Iosa1,2 1Private Inpatient Unit, 2Clinical Laboratory of Experimental Neurorehabilitation, IRCCS Santa Lucia Foundation, Rome, Italy; 3Department of Robotics, LIRMM UM-CNRS, Montpellier, France Abstract: In this review, we give a brief outline of robot-mediated gait training for stroke patients, as an important emerging field in rehabilitation. Technological innovations are allowing rehabilitation to move toward more integrated processes, with improved efficiency and less long-term impairments. In particular, robot-mediated neurorehabilitation is a rapidly advancing field, which uses robotic systems to define new methods for treating neurological injuries, especially stroke. The use of robots in gait training can enhance rehabilitation, but it needs to be used according to well-defined neuroscientific principles. The field of robot-mediated neurorehabilitation brings challenges to both bioengineering and clinical practice. This article reviews the state of the art (including commercially available systems and perspectives of robotics in poststroke rehabilitation for walking recovery. A critical revision, including the problems at stake regarding robotic clinical use, is also presented. Keywords: exoskeleton, neurorehabilitation, robot-assisted walking training, wearable robot, activities of daily living, motor learning, plasticity

Robot-assisted practice of gait and stair climbing in nonambulatory stroke patients.

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Hesse, Stefan; Tomelleri, Christopher; Bardeleben, Anita; Werner, Cordula; Waldner, Andreas

2012-01-01

A novel gait robot enabled nonambulatory patients the repetitive practice of gait and stair climbing. Thirty nonambulatory patients with subacute stroke were allocated to two groups. During 60 min sessions every workday for 4 weeks, the experimental group received 30 min of robot training and 30 min of physiotherapy and the control group received 60 min of physiotherapy. The primary variable was gait and stair climbing ability (Functional Ambulation Categories [FAC] score 0-5); secondary variables were gait velocity, Rivermead Mobility Index (RMI), and leg strength and tone blindly assessed at onset, intervention end, and follow-up. Both groups were comparable at onset and functionally improved over time. The improvements were significantly larger in the experimental group with respect to the FAC, RMI, velocity, and leg strength during the intervention. The FAC gains (mean +/- standard deviation) were 2.4 +/- 1.2 (experimental group) and 1.2 +/- 1.5 (control group), p = 0.01. At the end of the intervention, seven experimental group patients and one control group patient had reached an FAC score of 5, indicating an ability to climb up and down one flight of stairs. At follow-up, this superior gait ability persisted. In conclusion, the therapy on the novel gait robot resulted in a superior gait and stair climbing ability in nonambulatory patients with subacute stroke; a higher training intensity was the most likely explanation. A large randomized controlled trial should follow.

A pneumatically powered knee-ankle-foot orthosis (KAFO with myoelectric activation and inhibition

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Ferris Daniel P

2009-06-01

Full Text Available Abstract Background The goal of this study was to test the mechanical performance of a prototype knee-ankle-foot orthosis (KAFO powered by artificial pneumatic muscles during human walking. We had previously built a powered ankle-foot orthosis (AFO and used it effectively in studies on human motor adaptation, locomotion energetics, and gait rehabilitation. Extending the previous AFO to a KAFO presented additional challenges related to the force-length properties of the artificial pneumatic muscles and the presence of multiple antagonistic artificial pneumatic muscle pairs. Methods Three healthy males were fitted with custom KAFOs equipped with artificial pneumatic muscles to power ankle plantar flexion/dorsiflexion and knee extension/flexion. Subjects walked over ground at 1.25 m/s under four conditions without extensive practice: 1 without wearing the orthosis, 2 wearing the orthosis with artificial muscles turned off, 3 wearing the orthosis activated under direct proportional myoelectric control, and 4 wearing the orthosis activated under proportional myoelectric control with flexor inhibition produced by leg extensor muscle activation. We collected joint kinematics, ground reaction forces, electromyography, and orthosis kinetics. Results The KAFO produced ~22%–33% of the peak knee flexor moment, ~15%–33% of the peak extensor moment, ~42%–46% of the peak plantar flexor moment, and ~83%–129% of the peak dorsiflexor moment during normal walking. With flexor inhibition produced by leg extensor muscle activation, ankle (Pearson r-value = 0.74 ± 0.04 and knee ( r = 0.95 ± 0.04 joint kinematic profiles were more similar to the without orthosis condition compared to when there was no flexor inhibition (r = 0.49 ± 0.13 for ankle, p = 0.05, and r = 0.90 ± 0.03 for knee, p = 0.17. Conclusion The proportional myoelectric control with flexor inhibition allowed for a more normal gait than direct proportional myoelectric control. The current

A pneumatically powered knee-ankle-foot orthosis (KAFO) with myoelectric activation and inhibition

Science.gov (United States)

Sawicki, Gregory S; Ferris, Daniel P

2009-01-01

Background The goal of this study was to test the mechanical performance of a prototype knee-ankle-foot orthosis (KAFO) powered by artificial pneumatic muscles during human walking. We had previously built a powered ankle-foot orthosis (AFO) and used it effectively in studies on human motor adaptation, locomotion energetics, and gait rehabilitation. Extending the previous AFO to a KAFO presented additional challenges related to the force-length properties of the artificial pneumatic muscles and the presence of multiple antagonistic artificial pneumatic muscle pairs. Methods Three healthy males were fitted with custom KAFOs equipped with artificial pneumatic muscles to power ankle plantar flexion/dorsiflexion and knee extension/flexion. Subjects walked over ground at 1.25 m/s under four conditions without extensive practice: 1) without wearing the orthosis, 2) wearing the orthosis with artificial muscles turned off, 3) wearing the orthosis activated under direct proportional myoelectric control, and 4) wearing the orthosis activated under proportional myoelectric control with flexor inhibition produced by leg extensor muscle activation. We collected joint kinematics, ground reaction forces, electromyography, and orthosis kinetics. Results The KAFO produced ~22%–33% of the peak knee flexor moment, ~15%–33% of the peak extensor moment, ~42%–46% of the peak plantar flexor moment, and ~83%–129% of the peak dorsiflexor moment during normal walking. With flexor inhibition produced by leg extensor muscle activation, ankle (Pearson r-value = 0.74 ± 0.04) and knee ( r = 0.95 ± 0.04) joint kinematic profiles were more similar to the without orthosis condition compared to when there was no flexor inhibition (r = 0.49 ± 0.13 for ankle, p = 0.05, and r = 0.90 ± 0.03 for knee, p = 0.17). Conclusion The proportional myoelectric control with flexor inhibition allowed for a more normal gait than direct proportional myoelectric control. The current orthosis design

BioMot exoskeleton - Towards a smart wearable robot for symbiotic human-robot interaction.

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Bacek, Tomislav; Moltedo, Marta; Langlois, Kevin; Prieto, Guillermo Asin; Sanchez-Villamanan, Maria Carmen; Gonzalez-Vargas, Jose; Vanderborght, Bram; Lefeber, Dirk; Moreno, Juan C

2017-07-01

This paper presents design of a novel modular lower-limb gait exoskeleton built within the FP7 BioMot project. Exoskeleton employs a variable stiffness actuator in all 6 joints, a directional-flexibility structure and a novel physical humanrobot interfacing, which allows it to deliver the required output while minimally constraining user's gait by providing passive degrees of freedom. Due to modularity, the exoskeleton can be used as a full lower-limb orthosis, a single-joint orthosis in any of the three joints, and a two-joint orthosis in a combination of any of the two joints. By employing a simple torque control strategy, the exoskeleton can be used to deliver user-specific assistance, both in gait rehabilitation and in assisting people suffering musculoskeletal impairments. The result of the presented BioMot efforts is a low-footprint exoskeleton with powerful compliant actuators, simple, yet effective torque controller and easily adjustable flexible structure.

An accelerometry-based comparison of 2 robotic assistive devices for treadmill training of gait.

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Regnaux, Jean-Philippe; Saremi, Kaveh; Marehbian, Jon; Bussel, Bernard; Dobkin, Bruce H

2008-01-01

Two commercial robotic devices, the Gait Trainer (GT) and the Lokomat (LOKO), assist task-oriented practice of walking. The gait patterns induced by these motor-driven devices have not been characterized and compared. A healthy participant chose the most comfortable gait pattern on each device and for treadmill (TM) walking at 1, 2 (maximum for the GT), and 3 km/h and over ground at similar speeds. A system of accelerometers on the thighs and feet allowed the calculation of spatiotemporal features and accelerations during the gait cycle. At the 1 and 2 km/h speed settings, single-limb stance times were prolonged on the devices compared with overground walking. Differences on the LOKO were decreased by adjusting the hip and knee angles and step length. At the 3 km/h setting, the LOKO approximated the participant's overground parameters. Irregular accelerations and decelerations from toe-off to heel contact were induced by the devices, especially at slower speeds. The LOKO and GT impose mechanical constraints that may alter leg accelerations-decelerations during stance and swing phases, as well as stance duration, especially at their slower speed settings, that are not found during TM and overground walking. The potential impact of these perturbations on training to improve gait needs further study.

Research the Gait Characteristics of Human Walking Based on a Robot Model and Experiment

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He, H. J.; Zhang, D. N.; Yin, Z. W.; Shi, J. H.

2017-02-01

In order to research the gait characteristics of human walking in different walking ways, a robot model with a single degree of freedom is put up in this paper. The system control models of the robot are established through Matlab/Simulink toolbox. The gait characteristics of straight, uphill, turning, up the stairs, down the stairs up and down areanalyzed by the system control models. To verify the correctness of the theoretical analysis, an experiment was carried out. The comparison between theoretical results and experimental results shows that theoretical results are better agreement with the experimental ones. Analyze the reasons leading to amplitude error and phase error and give the improved methods. The robot model and experimental ways can provide foundation to further research the various gait characteristics of the exoskeleton robot.

Reflex control of robotic gait using human walking data.

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Catherine A Macleod

Full Text Available Control of human walking is not thoroughly understood, which has implications in developing suitable strategies for the retraining of a functional gait following neurological injuries such as spinal cord injury (SCI. Bipedal robots allow us to investigate simple elements of the complex nervous system to quantify their contribution to motor control. RunBot is a bipedal robot which operates through reflexes without using central pattern generators or trajectory planning algorithms. Ground contact information from the feet is used to activate motors in the legs, generating a gait cycle visually similar to that of humans. Rather than developing a more complicated biologically realistic neural system to control the robot's stepping, we have instead further simplified our model by measuring the correlation between heel contact and leg muscle activity (EMG in human subjects during walking and from this data created filter functions transferring the sensory data into motor actions. Adaptive filtering was used to identify the unknown transfer functions which translate the contact information into muscle activation signals. Our results show a causal relationship between ground contact information from the heel and EMG, which allows us to create a minimal, linear, analogue control system for controlling walking. The derived transfer functions were applied to RunBot II as a proof of concept. The gait cycle produced was stable and controlled, which is a positive indication that the transfer functions have potential for use in the control of assistive devices for the retraining of an efficient and effective gait with potential applications in SCI rehabilitation.

Active robotic training improves locomotor function in a stroke survivor

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Krishnan Chandramouli

2012-08-01

Full Text Available Abstract Background Clinical outcomes after robotic training are often not superior to conventional therapy. One key factor responsible for this is the use of control strategies that provide substantial guidance. This strategy not only leads to a reduction in volitional physical effort, but also interferes with motor relearning. Methods We tested the feasibility of a novel training approach (active robotic training using a powered gait orthosis (Lokomat in mitigating post-stroke gait impairments of a 52-year-old male stroke survivor. This gait training paradigm combined patient-cooperative robot-aided walking with a target-tracking task. The training lasted for 4-weeks (12 visits, 3 × per week. The subject’s neuromotor performance and recovery were evaluated using biomechanical, neuromuscular and clinical measures recorded at various time-points (pre-training, post-training, and 6-weeks after training. Results Active robotic training resulted in considerable increase in target-tracking accuracy and reduction in the kinematic variability of ankle trajectory during robot-aided treadmill walking. These improvements also transferred to overground walking as characterized by larger propulsive forces and more symmetric ground reaction forces (GRFs. Training also resulted in improvements in muscle coordination, which resembled patterns observed in healthy controls. These changes were accompanied by a reduction in motor cortical excitability (MCE of the vastus medialis, medial hamstrings, and gluteus medius muscles during treadmill walking. Importantly, active robotic training resulted in substantial improvements in several standard clinical and functional parameters. These improvements persisted during the follow-up evaluation at 6 weeks. Conclusions The results indicate that active robotic training appears to be a promising way of facilitating gait and physical function in moderately impaired stroke survivors.

Locomotor adaptation to a powered ankle-foot orthosis depends on control method

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Gordon Keith E

2007-12-01

Full Text Available Abstract Background We studied human locomotor adaptation to powered ankle-foot orthoses with the intent of identifying differences between two different orthosis control methods. The first orthosis control method used a footswitch to provide bang-bang control (a kinematic control and the second orthosis control method used a proportional myoelectric signal from the soleus (a physiological control. Both controllers activated an artificial pneumatic muscle providing plantar flexion torque. Methods Subjects walked on a treadmill for two thirty-minute sessions spaced three days apart under either footswitch control (n = 6 or myoelectric control (n = 6. We recorded lower limb electromyography (EMG, joint kinematics, and orthosis kinetics. We compared stance phase EMG amplitudes, correlation of joint angle patterns, and mechanical work performed by the powered orthosis between the two controllers over time. Results During steady state at the end of the second session, subjects using proportional myoelectric control had much lower soleus and gastrocnemius activation than the subjects using footswitch control. The substantial decrease in triceps surae recruitment allowed the proportional myoelectric control subjects to walk with ankle kinematics close to normal and reduce negative work performed by the orthosis. The footswitch control subjects walked with substantially perturbed ankle kinematics and performed more negative work with the orthosis. Conclusion These results provide evidence that the choice of orthosis control method can greatly alter how humans adapt to powered orthosis assistance during walking. Specifically, proportional myoelectric control results in larger reductions in muscle activation and gait kinematics more similar to normal compared to footswitch control.

Is body-weight-supported treadmill training or robotic-assisted gait training superior to overground gait training and other forms of physiotherapy in people with spinal cord injury? A systematic review.

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Mehrholz, J; Harvey, L A; Thomas, S; Elsner, B

2017-08-01

Systematic review about randomised trials comparing different training strategies to improve gait in people with spinal cord injuries (SCI). The aim of this systematic review was to compare the effectiveness of body-weight-supported treadmill training (BWSTT) and robotic-assisted gait training with overground gait training and other forms of physiotherapy in people with traumatic SCI. Systematic review conducted by researchers from Germany and Australia. An extensive search was conducted for randomised controlled trials involving people with traumatic SCI that compared either BWSTT or robotic-assisted gait training with overground gait training and other forms of physiotherapy. The two outcomes of interest were walking speed (m s -1 ) and walking distance (m). BWSTT and robotic-assisted gait training were analysed separately, and data were pooled across trials to derive mean between-group differences using a random-effects model. Thirteen randomised controlled trials involving 586 people were identified. Ten trials involving 462 participants compared BWSTT to overground gait training and other forms of physiotherapy, but only nine trials provided useable data. The pooled mean (95% confidence interval (CI)) between-group differences for walking speed and walking distance were -0.03 m s -1 (-0.10 to 0.04) and -7 m (-45 to 31), respectively, favouring overground gait training. Five trials involving 344 participants compared robotic-assisted gait training to overground gait training and other forms of physiotherapy but only three provided useable data. The pooled mean (95% CI) between-group differences for walking speed and walking distance were -0.04 m s -1 (95% CI -0.21 to 0.13) and -6 m (95% CI -86 to 74), respectively, favouring overground gait training. BWSTT and robotic-assisted gait training do not increase walking speed more than overground gait training and other forms of physiotherapy do, but their effects on walking distance are not clear.

A Neural Network-Based Gait Phase Classification Method Using Sensors Equipped on Lower Limb Exoskeleton Robots.

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Jung, Jun-Young; Heo, Wonho; Yang, Hyundae; Park, Hyunsub

2015-10-30

An exact classification of different gait phases is essential to enable the control of exoskeleton robots and detect the intentions of users. We propose a gait phase classification method based on neural networks using sensor signals from lower limb exoskeleton robots. In such robots, foot sensors with force sensing registers are commonly used to classify gait phases. We describe classifiers that use the orientation of each lower limb segment and the angular velocities of the joints to output the current gait phase. Experiments to obtain the input signals and desired outputs for the learning and validation process are conducted, and two neural network methods (a multilayer perceptron and nonlinear autoregressive with external inputs (NARX)) are used to develop an optimal classifier. Offline and online evaluations using four criteria are used to compare the performance of the classifiers. The proposed NARX-based method exhibits sufficiently good performance to replace foot sensors as a means of classifying gait phases.

[Exoskeleton robot system based on real-time gait analysis for walking assist].

Science.gov (United States)

Xie, Zheng; Wang, Mingjiang; Huang, Wulong; Yong, Shanshan; Wang, Xin'an

2017-04-01

This paper presents a wearable exoskeleton robot system to realize walking assist function, which oriented toward the patients or the elderly with the mild impairment of leg movement function, due to illness or natural aging. It reduces the loads of hip, knee, ankle and leg muscles during walking by way of weight support. In consideration of the characteristics of the psychological demands and the disease, unlike the weight loss system in the fixed or followed rehabilitation robot, the structure of the proposed exoskeleton robot is artistic, lightweight and portable. The exoskeleton system analyzes the user's gait real-timely by the plantar pressure sensors to divide gait phases, and present different control strategies for each gait phase. The pressure sensors in the seat of the exoskeleton system provide real-time monitoring of the support efforts. And the drive control uses proportion-integral-derivative (PID) control technology for torque control. The total weight of the robot system is about 12.5 kg. The average of the auxiliary support is about 10 kg during standing, and it is about 3 kg during walking. The system showed, in the experiments, a certain effect of weight support, and reduction of the pressure on the lower limbs to walk and stand.

Reduction of freezing of gait in Parkinson's disease by repetitive robot-assisted treadmill training: a pilot study

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Friedman Joseph H

2010-10-01

Full Text Available Abstract Background Parkinson's disease is a chronic, neurodegenerative disease characterized by gait abnormalities. Freezing of gait (FOG, an episodic inability to generate effective stepping, is reported as one of the most disabling and distressing parkinsonian symptoms. While there are no specific therapies to treat FOG, some external physical cues may alleviate these types of motor disruptions. The purpose of this study was to examine the potential effect of continuous physical cueing using robot-assisted sensorimotor gait training on reducing FOG episodes and improving gait. Methods Four individuals with Parkinson's disease and FOG symptoms received ten 30-minute sessions of robot-assisted gait training (Lokomat to facilitate repetitive, rhythmic, and alternating bilateral lower extremity movements. Outcomes included the FOG-Questionnaire, a clinician-rated video FOG score, spatiotemporal measures of gait, and the Parkinson's Disease Questionnaire-39 quality of life measure. Results All participants showed a reduction in FOG both by self-report and clinician-rated scoring upon completion of training. Improvements were also observed in gait velocity, stride length, rhythmicity, and coordination. Conclusions This pilot study suggests that robot-assisted gait training may be a feasible and effective method of reducing FOG and improving gait. Videotaped scoring of FOG has the potential advantage of providing additional data to complement FOG self-report.

Design of a robotic gait trainer using spring over muscle actuators for ankle stroke rehabilitation.

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Bharadwaj, Kartik; Sugar, Thomas G; Koeneman, James B; Koeneman, Edward J

2005-11-01

Repetitive task training is an effective form of rehabilitation for people suffering from debilitating injuries of stroke. We present the design and working concept of a robotic gait trainer (RGT), an ankle rehabilitation device for assisting stroke patients during gait. Structurally based on a tripod mechanism, the device is a parallel robot that incorporates two pneumatically powered, double-acting, compliant, spring over muscle actuators as actuation links which move the ankle in dorsiflex ion/plantarflexion and inversion/eversion. A unique feature in the tripod design is that the human anatomy is part of the robot, the first fixed link being the patient's leg. The kinematics and workspace of the tripod device have been analyzed determining its range of motion. Experimental gait data from an able-bodied person wearing the working RGT prototype are presented.

Effects of Robot Assisted Gait Training in Progressive Supranuclear Palsy (PSP: a preliminary report.

Directory of Open Access Journals (Sweden)

Patrizio eSale

2014-04-01

Full Text Available Background and Purpose: Progressive supranuclear palsy (PSP is a rare neurodegenerative disease clinically characterized by prominent axial extrapyramidal motor symptoms with frequent falls. Over the last years the introduction of robotic technologies to recover lower limb function has been greatly employed in the rehabilitative practice. This observational trial is aimed at investigating the feasibility, the effectiveness and the efficacy of end-effector robot training in people with PSP.Method: Pilot observational trial.Participants: Five cognitively intact participants with PSP and gait disorders.Interventions: Patients were submitted to a rehabilitative program of robot-assisted walking sessions for 45 minutes, 5 times a week for 4 weeks.Main outcome measures: The spatiotemporal parameters at the beginning (T0 and at the end of treatment (T1 were recorded by a gait analysis laboratory.Results: Robot training was feasible, acceptable and safe and all participants completed the prescribed training sessions. All patients showed an improvement in the gait index (Mean velocity, Cadence, Step length and Step width (T0 versus T1.Conclusions: Robot training is a feasible and safe form of rehabilitation for cognitively intact people with PSP. This innovative approach can contribute to improve lower limb motor recovery. The focus on gait recovery is another quality that makes this research important for clinical practice. On the whole, the simplicity of treatment, the lack of side effects and the positive results in the patients support the recommendation to extend the trials of this treatment. Further investigation regarding the effectiveness of robot training in time is necessary.Trial registration: ClinicalTrials.gov NCT01668407.

Generating high-speed dynamic running gaits in a quadruped robot using an evolutionary search.

Science.gov (United States)

Krasny, Darren P; Orin, David E

2004-08-01

Over the past several decades, there has been a considerable interest in investigating high-speed dynamic gaits for legged robots. While much research has been published, both in the biomechanics and engineering fields regarding the analysis of these gaits, no single study has adequately characterized the dynamics of high-speed running as can be achieved in a realistic, yet simple, robotic system. The goal of this paper is to find the most energy-efficient, natural, and unconstrained gallop that can be achieved using a simulated quadrupedal robot with articulated legs, asymmetric mass distribution, and compliant legs. For comparison purposes, we also implement the bound and canter. The model used here is planar, although we will show that it captures much of the predominant dynamic characteristics observed in animals. While it is not our goal to prove anything about biological locomotion, the dynamic similarities between the gaits we produce and those found in animals does indicate a similar underlying dynamic mechanism. Thus, we will show that achieving natural, efficient high-speed locomotion is possible even with a fairly simple robotic system. To generate the high-speed gaits, we use an efficient evolutionary algorithm called set-based stochastic optimization. This algorithm finds open-loop control parameters to generate periodic trajectories for the body. Several alternative methods are tested to generate periodic trajectories for the legs. The combined solutions found by the evolutionary search and the periodic-leg methods, over a range of speeds up to 10.0 m/s, reveal "biological" characteristics that are emergent properties of the underlying gaits.

Kinematic evaluation of mobile robotic platforms for overground gait neurorehabilitation

Science.gov (United States)

Alias, N. Akmal; Huq, M. Saiful; Ibrahim, B. S. K. K.; Omar, Rosli

2017-09-01

Gait assistive devices offer a great solution to the walking re-education which reduce patients theoretical limit by aiding the anatomical joints to be in line with the rehabilitation session. Overground gait training, which is differs significantly from body-weight supported treadmill training in many aspects, essentially consists of a mobile robotic base to support the subject securely (usually with overhead harness) while its motion and orientation is controlled seamlessly to facilitate subjects free movement. In this study, efforts have been made for evaluation of both holonomic and nonholonomic drives, the outcome of which may constitute the primarily results to the effective approach in designing a robotic platform for the mobile rehabilitation robot. The sets of kinematic equations are derived using typical geometries of two different drives. The results indicate that omnidirectional mecanum wheel platform is capable for more sophisticated discipline. Although the differential drive platform happens to be more simple and easy to construct, but it is less desirable as it has limited number of motions applicable to the system. The omnidirectional robot consisting of mecanum wheels, which is classified as holonomic is potentially the best solution in terms of its capability to move in arbitrary direction without concerning the changing of wheel's direction.

Foot loading with an ankle-foot orthosis: the accuracy of an integrated physical strain trainer.

Science.gov (United States)

Pauser, Johannes; Jendrissek, Andreas; Brem, Matthias; Gelse, Kolja; Swoboda, Bernd; Carl, Hans-Dieter

2012-07-01

To investigate the value of a built-in physical strain trainer for the monitoring of partial weight bearing with an ankle-foot orthosis. 12 healthy volunteers were asked to perform three trials. Plantar peak pressure values from normal gait (trial one) were defined as 100% (baseline). The following trials were performed with the Vacoped® dynamic vacuum ankle orthosis worn in a neutral position with full weight bearing (trial two) and a restriction to 10% body weight (BW) (trial three), as monitored with an integrated physical strain trainer. Peak plantar pressure values were obtained using the pedar® X system. Peak pressure values were statistically significantly reduced wearing the Vacoped® shoe with full weight bearing for the hindfoot to 68% of the baseline (normal gait) and for the midfoot and forefoot to 83% and 60%, respectively. Limited weight bearing with 10% BW as controlled by physical strain trainer further reduced plantar peak pressure values for the hindfoot to 19%, for the midfoot to 43% of the baseline and the forefoot to 22% of the baseline. The Vacoped® vacuum ankle orthosis significantly reduces plantar peak pressure. The integrated physical strain trainer seems unsuitable to monitor a limitation to 10% BW adequately for the total foot. The concept of controlling partial weight bearing with the hindfoot-addressing device within the orthosis seems debatable but may be useful when the hindfoot in particular must be off-loaded.

Dynamic bending of bionic flexible body driven by pneumatic artificial muscles(PAMs) for spinning gait of quadruped robot

Science.gov (United States)

Lei, Jingtao; Yu, Huangying; Wang, Tianmiao

2016-01-01

The body of quadruped robot is generally developed with the rigid structure. The mobility of quadruped robot depends on the mechanical properties of the body mechanism. It is difficult for quadruped robot with rigid structure to achieve better mobility walking or running in the unstructured environment. A kind of bionic flexible body mechanism for quadruped robot is proposed, which is composed of one bionic spine and four pneumatic artificial muscles(PAMs). This kind of body imitates the four-legged creatures' kinematical structure and physical properties, which has the characteristic of changeable stiffness, lightweight, flexible and better bionics. The kinematics of body bending is derived, and the coordinated movement between the flexible body and legs is analyzed. The relationship between the body bending angle and the PAM length is obtained. The dynamics of the body bending is derived by the floating coordinate method and Lagrangian method, and the driving force of PAM is determined. The experiment of body bending is conducted, and the dynamic bending characteristic of bionic flexible body is evaluated. Experimental results show that the bending angle of the bionic flexible body can reach 18°. An innovation body mechanism for quadruped robot is proposed, which has the characteristic of flexibility and achieve bending by changing gas pressure of PAMs. The coordinated movement of the body and legs can achieve spinning gait in order to improve the mobility of quadruped robot.

Powered Upper Limb Orthosis Actuation System Based on Pneumatic Artificial Muscles

Science.gov (United States)

Chakarov, Dimitar; Veneva, Ivanka; Tsveov, Mihail; Venev, Pavel

2018-03-01

The actuation system of a powered upper limb orthosis is studied in the work. To create natural safety in the mutual "man-robot" interaction, an actuation system based on pneumatic artificial muscles (PAM) is selected. Experimentally obtained force/contraction diagrams for bundles, consisting of different number of muscles are shown in the paper. The pooling force and the stiffness of the pneumatic actuators is assessed as a function of the number of muscles in the bundle and the supply pressure. Joint motion and torque is achieved by antagonistic actions through pulleys, driven by bundles of pneumatic muscles. Joint stiffness and joint torques are determined on condition of a power balance, as a function of the joint position, pressure, number of muscles and muscles

Polymer optical fiber strain gauge for human-robot interaction forces assessment on an active knee orthosis

Science.gov (United States)

Leal-Junior, Arnaldo G.; Frizera, Anselmo; Marques, Carlos; Sánchez, Manuel R. A.; Botelho, Thomaz R.; Segatto, Marcelo V.; Pontes, Maria José

2018-03-01

This paper presents the development of a polymer optical fiber (POF) strain gauge based on the light coupling principle, which the power attenuation is created by the misalignment between two POFs. The misalignment, in this case, is proportional to the strain on the structure that the fibers are attached. This principle has the advantages of low cost, ease of implementation, temperature insensitiveness, electromagnetic fields immunity and simplicity on the sensor interrogation and signal processing. Such advantages make the proposed solution an interesting alternative to the electronic strain gauges. For this reason, an analytical model for the POF strain gauge is proposed and validated. Furthermore, the proposed POF sensor is applied on an active orthosis for knee rehabilitation exercises through flexion/extension cycles. The controller of the orthosis provides 10 different levels of robotic assistance on the flexion/extension movement. The POF strain gauge is tested at each one of these levels. Results show good correlation between the optical and electronic strain gauges with root mean squared deviation (RMSD) of 1.87 Nm when all cycles are analyzed, which represents a deviation of less than 8%. For the application, the proposed sensor presented higher stability than the electronic one, which can provide advantages on the rehabilitation exercises and on the inner controller of the device.

The effect of a knee ankle foot orthosis incorporating an active knee mechanism on gait of a person with poliomyelitis.

Science.gov (United States)

Arazpour, Mokhtar; Chitsazan, Ahmad; Bani, Monireh Ahmadi; Rouhi, Gholamreza; Ghomshe, Farhad Tabatabai; Hutchins, Stephen W

2013-10-01

The aim of this case study was to identify the effect of a powered stance control knee ankle foot orthosis on the kinematics and temporospatial parameters of walking by a person with poliomyelitis when compared to a knee ankle foot orthosis. A knee ankle foot orthosis was initially manufactured by incorporating drop lock knee joints and custom molded ankle foot orthoses and fitted to a person with poliomyelitis. The orthosis was then adapted by adding electrically activated powered knee joints to provide knee extension torque during stance and also flexion torque in swing phase. Lower limb kinematic and kinetic data plus data for temporospatial parameters were acquired from three test walks using each orthosis. Walking speed, step length, and vertical and horizontal displacement of the pelvis decreased when walking with the powered stance control knee ankle foot orthosis compared to the knee ankle foot orthosis. When using the powered stance control knee ankle foot orthosis, the knee flexion achieved during swing and also the overall pattern of walking more closely matched that of normal human walking. The reduced walking speed may have caused the smaller compensatory motions detected when the powered stance control knee ankle foot orthosis was used. The new powered SCKAFO facilitated controlled knee flexion and extension during ambulation for a volunteer poliomyelitis person.

Human Gait Feature Extraction Including a Kinematic Analysis toward Robotic Power Assistance

Directory of Open Access Journals (Sweden)

Mario I. Chacon-Murguia

2012-09-01

Full Text Available The present work proposes a method for human gait and kinematic analysis. Gait analysis consists of the determination of hip, knee and ankle positions through video analysis. Gait kinematic for the thigh and knee is then generated from this data. Evaluations of the gait analysis method indicate an acceptable performance of 86.66% for hip and knee position estimation, and comparable findings with other reported works for gait kinematic. A coordinate systems assignment is performed according to the DH algorithm and a direct kinematic model of the legs is obtained. The legs' angles obtained from the video analysis are applied to the kinematic model in order to revise the application of this model to robotic legs in a power assisted system.

"You gotta try it all": Parents' Experiences with Robotic Gait Training for their Children with Cerebral Palsy.

Science.gov (United States)

Beveridge, Briony; Feltracco, Deanna; Struyf, Jillian; Strauss, Emily; Dang, Saniya; Phelan, Shanon; Wright, F Virginia; Gibson, Barbara E

2015-01-01

Innovative robotic technologies hold strong promise for improving walking abilities of children with cerebral palsy (CP), but may create expectations for parents pursuing the "newest thing" in treatment. The aim of this qualitative study was to explore parents' values about walking in relation to their experiences with robotic gait training for their children. Semi-structured interviews were conducted with parents of five ambulatory children with CP participating in a randomized trial investigating robotic gait training effectiveness. Parents valued walking, especially "correct" walking, as a key component of their children's present and future well-being. They continually sought the "next best thing" in therapy and viewed the robotic gait trainer as a potentially revolutionary technology despite mixed experiences. The results can help inform rehabilitation therapists' knowledge of parents' values and perspectives, and guide effective collaborations toward meeting the therapeutic needs of children with CP.

Continuous free-crab gaits for hexapod robots on a natural terrain with forbidden zones: An application to humanitarian demining

OpenAIRE

Estremera, Joaquín; Cobano, José A.; González de Santos, Pablo

2010-01-01

Autonomous robots are leaving the laboratories to master new outdoor applications, and walking robots in particular have already shown their potential advantages in these environments, especially on a natural terrain. Gait generation is the key to success in the negotiation of natural terrain with legged robots; however, most of the algorithms devised for hexapods have been tested under laboratory conditions. This paper presents the development of crab and turning gaits for hexapod robots on ...

Combining gait optimization with passive system to increase the energy efficiency of a humanoid robot walking movement

International Nuclear Information System (INIS)

Pereira, Ana I.; Lima, José; Costa, Paulo

2015-01-01

There are several approaches to create the Humanoid robot gait planning. This problem presents a large number of unknown parameters that should be found to make the humanoid robot to walk. Optimization in simulation models can be used to find the gait based on several criteria such as energy minimization, acceleration, step length among the others. The energy consumption can also be reduced with elastic elements coupled to each joint. The presented paper addresses an optimization method, the Stretched Simulated Annealing, that runs in an accurate and stable simulation model to find the optimal gait combined with elastic elements. Final results demonstrate that optimization is a valid gait planning technique

Combining gait optimization with passive system to increase the energy efficiency of a humanoid robot walking movement

Energy Technology Data Exchange (ETDEWEB)

Pereira, Ana I. [Polytechnic Institute of Bragança (Portugal); ALGORITMI,University of Minho (Portugal); Lima, José [Polytechnic Institute of Bragança (Portugal); INESC TEC (formerly INESC Porto) Porto (Portugal); Costa, Paulo [Faculty of Engineering, University of Porto (Portugal); INESC TEC (formerly INESC Porto) Porto (Portugal)

2015-03-10

There are several approaches to create the Humanoid robot gait planning. This problem presents a large number of unknown parameters that should be found to make the humanoid robot to walk. Optimization in simulation models can be used to find the gait based on several criteria such as energy minimization, acceleration, step length among the others. The energy consumption can also be reduced with elastic elements coupled to each joint. The presented paper addresses an optimization method, the Stretched Simulated Annealing, that runs in an accurate and stable simulation model to find the optimal gait combined with elastic elements. Final results demonstrate that optimization is a valid gait planning technique.

Flipper-driven terrestrial locomotion of a sea turtle-inspired robot

International Nuclear Information System (INIS)

Mazouchova, Nicole; Umbanhowar, Paul B; Goldman, Daniel I

2013-01-01

To discover principles of flipper-based terrestrial locomotion we study the mechanics of a hatchling sea turtle-inspired robot, FlipperBot (FBot), during quasi-static movement on granular media. FBot implements a symmetric gait using two servo-motor-driven front limbs with flat-plate flippers and either freely rotating or fixed wrist joints. For a range of gaits, FBot moves with a constant step length. However, for gaits with sufficiently shallow flipper penetration or sufficiently large stroke, per step displacement decreases with each successive step resulting in failure (zero forward displacement) within a few steps. For the fixed wrist, failure occurs when FBot interacts with ground disturbed during previous steps, and measurements reveal that flipper generated forces decrease as per step displacement decreases. The biologically inspired free wrist is less prone to failure, but slip-induced failure can still occur if FBot pitches forward and drives its leading edge into the substrate. In the constant step length regime, kinematic and force-based models accurately predict FBot's motion for free and fixed wrist configurations, respectively. When combined with independent force measurements, models and experiments provide insight into how disturbed ground leads to locomotory failure and help explain differences in hatchling sea turtle performance. (paper)

Trotting Gait of a Quadruped Robot Based on the Time-Pose Control Method

Directory of Open Access Journals (Sweden)

Cai RunBin

2013-02-01

Full Text Available We present the Time-Pose control method for the trotting gait of a quadruped robot on flat ground and up a slope. The method, with brief control structure, real-time operation ability and high adaptability, divides quadruped robot control into gait control and pose control. Virtual leg and intuitive controllers are introduced to simplify the model and generate the trajectory of mass centre and location of supporting legs in gait control, while redundancy optimization is used for solving the inverse kinematics in pose control. The models both on flat ground and up a slope are fully analysed, and different kinds of optimization methods are compared using the manipulability measure in order to select the best option. Simulations are performed, which prove that the Time-Pose control method is realizable for these two kinds of environment.

Kinematic Gait Changes Following Serial Casting and Bracing to Treat Toe Walking in a Child With Autism.

Science.gov (United States)

Barkocy, Marybeth; Dexter, James; Petranovich, Colleen

2017-07-01

To evaluate the effectiveness of serial casting in a child with autism spectrum disorder (ASD) exhibiting a toe-walking gait pattern with equinus contractures. Although many children with ASD toe walk, little research on physical therapy interventions exists for this population. Serial casting has been validated for use in idiopathic toe walking to increase passive dorsiflexion and improve gait, but not for toe walking in children with ASD. Serial casting followed by ankle-foot orthosis use was implemented to treat a child with ASD who had an obligatory equinus gait pattern. Gait analysis supported improvements in kinematic, spatial, and temporal parameters of gait, and the child maintained a consistent heel-toe gait at 2-year follow-up. STATEMENT OF CONCLUSION AND RECOMMENDATIONS FOR CLINICAL PRACTICE:: Serial casting followed by ankle-foot orthosis use is a viable treatment option for toe walking in children with ASD.

Biomechanics of the immediate impact of wearing a rigid thoracolumbar corset on gait kinematics and spatiotemporal parameters

Directory of Open Access Journals (Sweden)

Taiar Redha

2018-01-01

Full Text Available The corset support is a device classified as orthosis. It compensates a functional deficiency with means of protection, recovery, correction, maintenance, and support or contention. There are two types of orthosis 1 rest orthosis and 2 corrective orthosis. Rest orthosis maintains joints in a defined position to avoid deformities or to relieve a pain at joints. Corrective orthosis adjusts joint deformity either passively or actively. Corset is used in various pathological use, thoracic-lumbar fracture, scoliosis, Scheuermann’s disease or spinal dystrophy. The purpose of this study was 1 to determine the immediate impact of wearing a semi-rigid thoracolumbar corset, the Lombax® Dorso on gait kinematics and 2 spatiotemporal parameters in 6 adults. These parameters were recorded using the optoelectronic system Vicon® on treadmill gait subjects with and without corset for the comparison. The results showed that wearing a corset significantly decrease the rotation amplitudes of the scapular and pelvic girdles (p<0.05 in the frontal plane. The movement of the pelvis and hip in this same plane was decreased also when comparing with and without a corset effects (p<0.05. The corset significantly increased the range of flexion-extension of the hip during the gait cycle. At the conclusion of this study the discriminate parameters of wearing a corset was quantified. The results and in association with manufacturer will help to improve materials for better optimization support. Comparable perspectives and after improvement of materials will aim to experiment with patients on real daily life situation.

Robot-assisted gait training in patients with Parkinson disease: a randomized controlled trial.

Science.gov (United States)

Picelli, Alessandro; Melotti, Camilla; Origano, Francesca; Waldner, Andreas; Fiaschi, Antonio; Santilli, Valter; Smania, Nicola

2012-05-01

. Gait impairment is a common cause of disability in Parkinson disease (PD). Electromechanical devices to assist stepping have been suggested as a potential intervention. . To evaluate whether a rehabilitation program of robot-assisted gait training (RAGT) is more effective than conventional physiotherapy to improve walking. . A total of 41 patients with PD were randomly assigned to 45-minute treatment sessions (12 in all), 3 days a week, for 4 consecutive weeks of either robotic stepper training (RST; n = 21) using the Gait Trainer or physiotherapy (PT; n = 20) with active joint mobilization and a modest amount of conventional gait training. Participants were evaluated before, immediately after, and 1 month after treatment. Primary outcomes were 10-m walking speed and distance walked in 6 minutes. . Baseline measures revealed no statistical differences between groups, but the PT group walked 0.12 m/s slower; 5 patients withdrew. A statistically significant improvement was found in favor of the RST group (walking speed 1.22 ± 0.19 m/s [P = .035]; distance 366.06 ± 78.54 m [P < .001]) compared with the PT group (0.98 ± 0.32 m/s; 280.11 ± 106.61 m). The RAGT mean speed increased by 0.13 m/s, which is probably not clinically important. Improvements were maintained 1 month later. . RAGT may improve aspects of walking ability in patients with PD. Future trials should compare robotic assistive training with treadmill or equal amounts of overground walking practice.

FUZZY CONTROLLER FOR THE CONTROL OF THE MOBILE PLATFORM OF THE CORBYS ROBOTIC GAIT REHABILITATION SYSTEM

Directory of Open Access Journals (Sweden)

Maria Kyrarini

2014-12-01

Full Text Available In this paper, an inverse kinematics based control algorithm for the joystick control of the mobile platform of the novel mobile robot-assisted gait rehabilitation system CORBYS is presented. The mobile platform has four independently steered and driven wheels. Given the linear and angular velocities of the mobile platform, the inverse kinematics algorithm gives as its output the steering angle and the driving angular velocity of each of the four wheels. The paper is focused on the steering control of the platform for which a fuzzy logic controller is developed and implemented. The experimental results of the real-world steering of the platform are presented in the paper.

Adaptive locomotor training on an end-effector gait robot: evaluation of the ground reaction forces in different training conditions.

Science.gov (United States)

Tomelleri, Christopher; Waldner, Andreas; Werner, Cordula; Hesse, Stefan

2011-01-01

The main goal of robotic gait rehabilitation is the restoration of independent gait. To achieve this goal different and specific patterns have to be practiced intensively in order to stimulate the learning process of the central nervous system. The gait robot G-EO Systems was designed to allow the repetitive practice of floor walking, stair climbing and stair descending. A novel control strategy allows training in adaptive mode. The force interactions between the foot and the ground were analyzed on 8 healthy volunteers in three different conditions: real floor walking on a treadmill, floor walking on the gait robot in passive mode, floor walking on the gait robot in adaptive mode. The ground reaction forces were measured by a Computer Dyno Graphy (CDG) analysis system. The results show different intensities of the ground reaction force across all of the three conditions. The intensities of force interactions during the adaptive training mode are comparable to the real walking on the treadmill. Slight deviations still occur in regard to the timing pattern of the forces. The adaptive control strategy comes closer to the physiological swing phase than the passive mode and seems to be a promising option for the treatment of gait disorders. Clinical trials will validate the efficacy of this new option in locomotor therapy on the patients. © 2011 IEEE

Restoration of gait for spinal cord injury patients using HAL with intention estimator for preferable swing speed.

Science.gov (United States)

Tsukahara, Atsushi; Hasegawa, Yasuhisa; Eguchi, Kiyoshi; Sankai, Yoshiyuki

2015-03-01

This paper proposes a novel gait intention estimator for an exoskeleton-wearer who needs gait support owing to walking impairment. The gait intention estimator not only detects the intention related to the start of the swing leg based on the behavior of the center of ground reaction force (CoGRF), but also infers the swing speed depending on the walking velocity. The preliminary experiments categorized into two stages were performed on a mannequin equipped with the exoskeleton robot [Hybrid Assistive Limb: (HAL)] including the proposed estimator. The first experiment verified that the gait support system allowed the mannequin to walk properly and safely. In the second experiment, we confirmed the differences in gait characteristics attributed to the presence or absence of the proposed swing speed profile. As a feasibility study, we evaluated the walking capability of a severe spinal cord injury patient supported by the system during a 10-m walk test. The results showed that the system enabled the patient to accomplish a symmetrical walk from both spatial and temporal standpoints while adjusting the speed of the swing leg. Furthermore, the critical differences of gait between our system and a knee-ankle-foot orthosis were obtained from the CoGRF distribution and the walking time. Through the tests, we demonstrated the effectiveness and practical feasibility of the gait support algorithms.

Light-driven robotics for nanoscopy

DEFF Research Database (Denmark)

Glückstad, Jesper; Palima, Darwin

2013-01-01

The science fiction inspired shrinking of macro-scale robotic manipulation and handling down to the micro- and nanoscale regime opens new doors for exploiting the forces and torques of light for micro- and nanoscopic probing, actuation and control. Advancing light-driven micro-robotics requires...... and matter for robotically probing at the smallest biological length scales....

Evaluation of gait performance of a participant with Perthes disease while walking with and without a Scottish-Rite orthosis.

Science.gov (United States)

Karimi, Mohammad; Sedigh, Jafar; Fatoye, Francis

2013-06-01

Scottish-Rite orthosis is one of the conservative methods used to treat Legg-Calvé-Perthes disease. As there was not enough evidence to show the effects of using this orthosis on reducing the loads applied on the limb, this research aimed to find the influence of this orthosis. A participant with Perthes disease on the left hip joint was recruited into this study to walk with and without the orthosis. The kinetic and kinematic parameters were collected by a motion analysis system and a Kistler force platform. No significant differences were noted between the hip joint flexion/extension range of motion and the moments between the sound side and the side affected by Legg-Calvé-Perthes disease. It may be concluded that use of orthosis may not have any positive effects to decrease the loads or to improve the alignment of the hip joint in participants with Perthes disease, as expected. The use of Scottish-Rite orthosis not only does not improve the containment of the hip joint, but also does not have any significant influence on loads applied on the joint during walking of the subject with Perthes disease. The results of this research can be used by clinicians involved in treatment of patients with Legg-Calvé-Perthes disease.

[The influence of locomotor treatment using robotic body-weight-supported treadmill training on rehabilitation outcome of patients suffering from neurological disorders].

Science.gov (United States)

Schwartz, Isabella; Meiner, Zeev

2013-03-01

Regaining one's ability to walk is of great importance for neurological patients and is a major goal of all rehabilitation programs. Treating neurological patients in the acute phase after the event is technically difficult because of their motor weakness and balance disturbances. Based on studies in spinalized animals, a novel locomotor training that incorporates high repetitions of task-oriented practice by the use of body weight-supported treadmill training (BWSTT) was developed to overcome these obstacles. The use of BWSTT enables early initiation of gait training, integration of weightbearing activities, stepping and balance by the use of a task-specific approach, and a symmetrical gait pattern. However, despite the theoretical potential of BWSTT to become an invaluable therapeutic tool, its effect on walking outcomes was disappointing when compared with conventional training of the same duration. To facilitate the deLivery of BWSTT, a motorized robotic driven gait orthosis (RBWSTT) was recently developed. It has many advantages over the conventional method, including less effort for the physiotherapists, longer session duration, more physiological and reproducible gait patterns, and the possibility of measuring a patient's performances. Several studies have been conducted using RBWSTT in patients after stroke, spinal cord injury, multiple sclerosis and other neurological diseases. Although some of the results were encouraging, there is still uncertainty regarding proper patient selection, timing and protocol for RBWTT treatment following neurological diseases. More large randomized controlled studies are needed in order to answer these questions.

Balanced gait generations of a two-legged robot on sloping surface

Indian Academy of Sciences (India)

legged robot moving up and down through the sloping surface is presented. The gait of the lower links during locomotion is obtained after assuming suitable trajectories for the swing leg and hip joint. The trunk motion is initially generated based on ...

Biomechanics of an orthosis-managed cranial cruciate ligament-deficient canine stifle joint predicted by use of a computer model.

Science.gov (United States)

Bertocci, Gina E; Brown, Nathan P; Mich, Patrice M

2017-01-01

OBJECTIVE To evaluate effects of an orthosis on biomechanics of a cranial cruciate ligament (CrCL)-deficient canine stifle joint by use of a 3-D quasistatic rigid-body pelvic limb computer model simulating the stance phase of gait and to investigate influences of orthosis hinge stiffness (durometer). SAMPLE A previously developed computer simulation model for a healthy 33-kg 5-year-old neutered Golden Retriever. PROCEDURES A custom stifle joint orthosis was implemented in the CrCL-deficient pelvic limb computer simulation model. Ligament loads, relative tibial translation, and relative tibial rotation in the orthosis-stabilized stifle joint (baseline scenario; high-durometer hinge]) were determined and compared with values for CrCL-intact and CrCL-deficient stifle joints. Sensitivity analysis was conducted to evaluate the influence of orthosis hinge stiffness on model outcome measures. RESULTS The orthosis decreased loads placed on the caudal cruciate and lateral collateral ligaments and increased load placed on the medial collateral ligament, compared with loads for the CrCL-intact stifle joint. Ligament loads were decreased in the orthosis-managed CrCL-deficient stifle joint, compared with loads for the CrCL-deficient stifle joint. Relative tibial translation and rotation decreased but were not eliminated after orthosis management. Increased orthosis hinge stiffness reduced tibial translation and rotation, whereas decreased hinge stiffness increased internal tibial rotation, compared with values for the baseline scenario. CONCLUSIONS AND CLINICAL RELEVANCE Stifle joint biomechanics were improved following orthosis implementation, compared with biomechanics of the CrCL-deficient stifle joint. Orthosis hinge stiffness influenced stifle joint biomechanics. An orthosis may be a viable option to stabilize a CrCL-deficient canine stifle joint.

Hybrid FES-robot cooperative control of ambulatory gait rehabilitation exoskeleton.

Science.gov (United States)

del-Ama, Antonio J; Gil-Agudo, Angel; Pons, José L; Moreno, Juan C

2014-03-04

Robotic and functional electrical stimulation (FES) approaches are used for rehabilitation of walking impairment of spinal cord injured individuals. Although devices are commercially available, there are still issues that remain to be solved. Control of hybrid exoskeletons aims at blending robotic exoskeletons and electrical stimulation to overcome the drawbacks of each approach while preserving their advantages. Hybrid actuation and control have a considerable potential for walking rehabilitation but there is a need of novel control strategies of hybrid systems that adequately manage the balance between FES and robotic controllers. Combination of FES and robotic control is a challenging issue, due to the non-linear behavior of muscle under stimulation and the lack of developments in the field of hybrid control. In this article, a cooperative control strategy of a hybrid exoskeleton is presented. This strategy is designed to overcome the main disadvantages of muscular stimulation: electromechanical delay and change in muscle performance over time, and to balance muscular and robotic actuation during walking.Experimental results in healthy subjects show the ability of the hybrid FES-robot cooperative control to balance power contribution between exoskeleton and muscle stimulation. The robotic exoskeleton decreases assistance while adequate knee kinematics are guaranteed. A new technique to monitor muscle performance is employed, which allows to estimate muscle fatigue and implement muscle fatigue management strategies. Kinesis is therefore the first ambulatory hybrid exoskeleton that can effectively balance robotic and FES actuation during walking. This represents a new opportunity to implement new rehabilitation interventions to induce locomotor activity in patients with paraplegia.Acronym list: 10 mWT: ten meters walking test; 6 MWT: six minutes walking test; FSM: finite-state machine; t-FSM: time-domain FSM; c-FSM: cycle-domain FSM; FES: functional electrical

Statically vs dynamically balanced gait: Analysis of a robotic exoskeleton compared with a human.

Science.gov (United States)

Barbareschi, Giulia; Richards, Rosie; Thornton, Matt; Carlson, Tom; Holloway, Catherine

2015-01-01

In recent years exoskeletons able to replicate human gait have begun to attract growing popularity for both assistive and rehabilitative purposes. Although wearable robots often need the use of external support in order to maintain stability, the REX exoskeleton by REX Bionics is able to self-balance through the whole cycle. However this statically balanced gait presents important differences with the dynamically balanced gait of human subjects. This paper will examine kinematic and kinetic differences between the gait analysis performed on a subject wearing the REX exoskeleton and human gait analysis data as presented in literature. We will also provide an insight on the impact that these differences can have for both rehabilitative and assistive applications.

What does best evidence tell us about robotic gait rehabilitation in stroke patients: A systematic review and meta-analysis.

Science.gov (United States)

Bruni, Maria Federica; Melegari, Corrado; De Cola, Maria Cristina; Bramanti, Alessia; Bramanti, Placido; Calabrò, Rocco Salvatore

2018-02-01

Studies about electromechanical-assisted devices proved the validity and effectiveness of these tools in gait rehabilitation, especially if used in association with conventional physiotherapy in stroke patients. The aim of this study was to compare the effects of different robotic devices in improving post-stroke gait abnormalities. A computerized literature research of articles was conducted in the databases MEDLINE, PEDro, COCHRANE, besides a search for the same items in the Library System of the University of Parma (Italy). We selected 13 randomized controlled trials, and the results were divided into sub-acute stroke patients and chronic stroke patients. We selected studies including at least one of the following test: 10-Meter Walking Test, 6-Minute Walk Test, Timed-Up-and-Go, 5-Meter Walk Test, and Functional Ambulation Categories. Stroke patients who received physiotherapy treatment in combination with robotic devices, such as Lokomat or Gait Trainer, were more likely to reach better results, compared to patients who receive conventional gait training alone. Moreover, electromechanical-assisted gait training in association with Functional Electrical Stimulations produced more benefits than the only robotic treatment (-0.80 [-1.14; -0.46], p > .05). The evaluation of the results confirm that the use of robotics can positively affect the outcome of a gait rehabilitation in patients with stroke. The effects of different devices seems to be similar on the most commonly outcome evaluated by this review. Copyright © 2017 Elsevier Ltd. All rights reserved.

Conflicting results of robot-assisted versus usual gait training during postacute rehabilitation of stroke patients: a randomized clinical trial

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Taveggia, Giovanni; Borboni, Alberto; Mulé, Chiara; Negrini, Stefano

2016-01-01

Robot gait training has the potential to increase the effectiveness of walking therapy. Clinical outcomes after robotic training are often not superior to conventional therapy. We evaluated the effectiveness of a robot training compared with a usual gait training physiotherapy during a standardized rehabilitation protocol in inpatient participants with poststroke hemiparesis. This was a randomized double-blind clinical trial in a postacute physical and rehabilitation medicine hospital. Twenty-eight patients, 39.3% women (72±6 years), with hemiparesis (Bobath approach were assigned randomly to an experimental or a control intervention of robot gait training to improve walking (five sessions a week for 5 weeks). Outcome measures included the 6-min walk test, the 10 m walk test, Functional Independence Measure, SF-36 physical functioning and the Tinetti scale. Outcomes were collected at baseline, immediately following the intervention period and 3 months following the end of the intervention. The experimental group showed a significant increase in functional independence and gait speed (10 m walk test) at the end of the treatment and follow-up, higher than the minimal detectable change. The control group showed a significant increase in the gait endurance (6-min walk test) at the follow-up, higher than the minimal detectable change. Both treatments were effective in the improvement of gait performances, although the statistical analysis of functional independence showed a significant improvement in the experimental group, indicating possible advantages during generic activities of daily living compared with overground treatment. PMID:26512928

Controlling patient participation during robot-assisted gait training

Science.gov (United States)

2011-01-01

Background The overall goal of this paper was to investigate approaches to controlling active participation in stroke patients during robot-assisted gait therapy. Although active physical participation during gait rehabilitation after stroke was shown to improve therapy outcome, some patients can behave passively during rehabilitation, not maximally benefiting from the gait training. Up to now, there has not been an effective method for forcing patient activity to the desired level that would most benefit stroke patients with a broad variety of cognitive and biomechanical impairments. Methods Patient activity was quantified in two ways: by heart rate (HR), a physiological parameter that reflected physical effort during body weight supported treadmill training, and by a weighted sum of the interaction torques (WIT) between robot and patient, recorded from hip and knee joints of both legs. We recorded data in three experiments, each with five stroke patients, and controlled HR and WIT to a desired temporal profile. Depending on the patient's cognitive capabilities, two different approaches were taken: either by allowing voluntary patient effort via visual instructions or by forcing the patient to vary physical effort by adapting the treadmill speed. Results We successfully controlled patient activity quantified by WIT and by HR to a desired level. The setup was thereby individually adaptable to the specific cognitive and biomechanical needs of each patient. Conclusion Based on the three successful approaches to controlling patient participation, we propose a metric which enables clinicians to select the best strategy for each patient, according to the patient's physical and cognitive capabilities. Our framework will enable therapists to challenge the patient to more activity by automatically controlling the patient effort to a desired level. We expect that the increase in activity will lead to improved rehabilitation outcome. PMID:21429200

LOPES: Selective control of gait functions during the gait rehabilitation of CVA patients

NARCIS (Netherlands)

Ekkelenkamp, R.; Veneman, J.F.; van der Kooij, Herman

2005-01-01

LOPES aims for an active role of the patient by selective and partial support of gait functions during robotic treadmill training sessions. Virtual model control (VMC) was applied to the robot as an intuitive method for translating current treadmill gait rehabilitation therapy programs into robotic

First clinical results with the new innovative robotic gait trainer LOPES

NARCIS (Netherlands)

Nikamp-Simons, Corien Diana Maria; van Asseldonk, Edwin H.F.; Folkersma, Marjanne; van den Hoek, Joelle; Postma, Martijn; Buurke, Jaap

2009-01-01

The results of five chronic stroke patients in a first explorative training study using the new robotic device LOPES are presented. Conclusions Positive effects of gait training in LOPES were found in four out of five subjects. Future study will focus on including larger sample sizes and introducing

Gastrocnemius tendon strain in a dog treated with autologous mesenchymal stem cells and a custom orthosis.

Science.gov (United States)

Case, J Brad; Palmer, Ross; Valdes-Martinez, Alex; Egger, Erick L; Haussler, Kevin K

2013-05-01

To report clinical findings and outcome in a dog with gastrocnemius tendon strain treated with autologous mesenchymal stem cells and a custom orthosis. Clinical report. A 4-year-old spayed female Border Collie. Bone-marrow derived, autologous mesenchymal stem cells were transplanted into the tendon core lesion. A custom, progressive, dynamic orthosis was fit to the tarsus. Serial orthopedic examinations and ultrasonography as well as long-term force-plate gait analysis were utilized for follow up. Lameness subjectively resolved and peak vertical force increased from 43% to 92% of the contralateral pelvic limb. Serial ultrasonographic examinations revealed improved but incomplete restoration of normal linear fiber pattern of the gastrocnemius tendon. Findings suggest that autologous mesenchymal stem cell transplantation with custom, progressive, dynamic orthosis may be a viable, minimally invasive technique for treatment of calcaneal tendon injuries in dogs. © Copyright 2013 by The American College of Veterinary Surgeons.

Smooth and Energy Saving Gait Planning for Humanoid Robot Using Geodesics

Directory of Open Access Journals (Sweden)

Liandong Zhang

2012-01-01

Full Text Available A novel gait planning method using geodesics for humanoid robot is given in this paper. Both the linear inverted pendulum model and the exact Single Support Phase (SSP are studied in our energy optimal gait planning based on geodesics. The kinetic energy of a 2-dimension linear inverted pendulum is obtained at first. We regard the kinetic energy as the Riemannian metric and the geodesic on this metric is studied and this is the shortest line between two points on the Riemannian surface. This geodesic is the optimal kinetic energy gait for the COG because the kinetic energy along geodesic is invariant according to the geometric property of geodesics and the walking is smooth and energy saving. Then the walking in Single Support Phase is studied and the energy optimal gait for the swing leg is obtained using our geodesics method. Finally, experiments using state-of-the-art method and using our geodesics optimization method are carried out respectively and the corresponding currents of the joint motors are recorded. With the currents comparing results, the feasibility of this new gait planning method is verified.

2nd International Conference on Cable-Driven Parallel Robots

CERN Document Server

Bruckmann, Tobias

2015-01-01

This volume presents the outcome of the second forum to cable-driven parallel robots, bringing the cable robot community together. It shows the new ideas of the active researchers developing cable-driven robots. The book presents the state of the art, including both summarizing contributions as well as latest research and future options. The book cover all topics which are essential for cable-driven robots: Classification Kinematics, Workspace and Singularity Analysis Statics and Dynamics Cable Modeling Control and Calibration Design Methodology Hardware Development Experimental Evaluation Prototypes, Application Reports and new Application concepts

COMPARISON BETWEEN PHYSIOLOGICAL COST INDEX IN HEALTHY NORMAL CHILDREN AS AGAINST AMBULATORY SPASTIC DIPLEGIC CEREBRAL PALSY (WITH AND WITHOUT ORTHOSIS IN THE AGE GROUP 6 TO 18 YEARS

Directory of Open Access Journals (Sweden)

Swatia Bhise

2016-08-01

Full Text Available Background: Efficacy of rehabilitation program for subjects with orthosis with objective measurement. The study aiming to objectively compare the PCI and walking speed of normal children with ambulatory spastic diaplegic. Also we aimed to analyze whether BMIhad impact on energy cost. Methods: 41 normal children and 41 community walking spastic diaplegic aged between 6 to 18 yrs. were assessed to compare the PCI. Speed of walking and heart rate were checked constantlyboth barefoot and in shoes in normal children and with and without conventional AFO in children with spastic diaplegic at their chosen velocities over four consecutive lengths of a 12.5m walkway i.e. total 50m.,Pre and Post readings are taken. Heart rate is affected by speed; PCI with speed of walking and heart rate was calculated for each child. Results: The mean PCI in shoes and barefoot was same in normal children i.e. 0.05 ±0.039beats/meter. The PCI for children with pathological gait i.e. spastic diaplegic without orthosis and with orthosis is 0.199 ±0.176 and 0.104± 0.093beats/meter appreciably greater than that for normal children(p less than 0.05. Conclusion: This study showed that walking with orthosis in spastic diplegic CP children showed higher costs of energy and slower walking speed compared normal children with age matched. The PCI of walking, with orthosis in children with spastic Diplegic cerebral palsy is less as compared to without orthosis i.e. gait is more energy efficient with orthosis. BMI doesn’t show any correlation with PCI further study may require.

Effectiveness of an Articulated Knee Hyperextension Orthosis in Genu Recurvatum

Directory of Open Access Journals (Sweden)

Rahul ASRM

2014-08-01

Full Text Available Genu Recurvatum is a deformity of knee joint that tends to push it backwards by excessive extension in tibio-femoral joints. This poses a significant challenge because of technical difficulties and a high incidence of recurrence. This report describes a 63 years old male diagnosed as post-polio residual paralysis who showed excessive genu recurvatum of his left knee during long standing and walking. An Articulated Knee Hyperextension Orthosis (KAFO was tried to check its effectiveness in terms of gait and energy expenditure.

Hemorrhagic versus ischemic stroke: Who can best benefit from blended conventional physiotherapy with robotic-assisted gait therapy?

Science.gov (United States)

Dierick, Frédéric; Dehas, Mélanie; Isambert, Jean-Luc; Injeyan, Soizic; Bouché, Anne-France; Bleyenheuft, Yannick; Portnoy, Sigal

2017-01-01

Contrary to common belief of clinicians that hemorrhagic stroke survivors have better functional prognoses than ischemic, recent studies show that ischemic survivors could experience similar or even better functional improvements. However, the influence of stroke subtype on gait and posture outcomes following an intervention blending conventional physiotherapy with robotic-assisted gait therapy is missing. This study compared gait and posture outcome measures between ambulatory hemorrhagic patients and ischemic patients, who received a similar 4 weeks' intervention blending a conventional bottom-up physiotherapy approach and an exoskeleton top-down robotic-assisted gait training (RAGT) approach with Lokomat. Forty adult hemiparetic stroke inpatient subjects were recruited: 20 hemorrhagic and 20 ischemic, matched by age, gender, side of hemisphere lesion, stroke severity, and locomotor impairments. Functional Ambulation Category, Postural Assessment Scale for Stroke, Tinetti Performance Oriented Mobility Assessment, 6 Minutes Walk Test, Timed Up and Go and 10-Meter Walk Test were performed before and after a 4-week long intervention. Functional gains were calculated for all tests. Hemorrhagic and ischemic subjects showed significant improvements in Functional Ambulation Category (Pbenefits from the same type, length and frequency of blended conventional physiotherapy and RAGT protocol. The use of intensive treatment plans blending top-down physiotherapy and bottom-up robotic approaches is promising for post-stroke rehabilitation.

Toward Multimodal Human-Robot Interaction to Enhance Active Participation of Users in Gait Rehabilitation.

Science.gov (United States)

Gui, Kai; Liu, Honghai; Zhang, Dingguo

2017-11-01

Robotic exoskeletons for physical rehabilitation have been utilized for retraining patients suffering from paraplegia and enhancing motor recovery in recent years. However, users are not voluntarily involved in most systems. This paper aims to develop a locomotion trainer with multiple gait patterns, which can be controlled by the active motion intention of users. A multimodal human-robot interaction (HRI) system is established to enhance subject's active participation during gait rehabilitation, which includes cognitive HRI (cHRI) and physical HRI (pHRI). The cHRI adopts brain-computer interface based on steady-state visual evoked potential. The pHRI is realized via admittance control based on electromyography. A central pattern generator is utilized to produce rhythmic and continuous lower joint trajectories, and its state variables are regulated by cHRI and pHRI. A custom-made leg exoskeleton prototype with the proposed multimodal HRI is tested on healthy subjects and stroke patients. The results show that voluntary and active participation can be effectively involved to achieve various assistive gait patterns.

The effect of impedance-controlled robotic gait training on walking ability and quality in individuals with chronic incomplete spinal cord injury: an explorative study.

Science.gov (United States)

Fleerkotte, Bertine M; Koopman, Bram; Buurke, Jaap H; van Asseldonk, Edwin H F; van der Kooij, Herman; Rietman, Johan S

2014-03-04

There is increasing interest in the use of robotic gait-training devices in walking rehabilitation of incomplete spinal cord injured (iSCI) individuals. These devices provide promising opportunities to increase the intensity of training and reduce physical demands on therapists. Despite these potential benefits, robotic gait-training devices have not yet demonstrated clear advantages over conventional gait-training approaches, in terms of functional outcomes. This might be due to the reduced active participation and step-to-step variability in most robotic gait-training strategies, when compared to manually assisted therapy. Impedance-controlled devices can increase active participation and step-to-step variability. The aim of this study was to assess the effect of impedance-controlled robotic gait training on walking ability and quality in chronic iSCI individuals. A group of 10 individuals with chronic iSCI participated in an explorative clinical trial. Participants trained three times a week for eight weeks using an impedance-controlled robotic gait trainer (LOPES: LOwer extremity Powered ExoSkeleton). Primary outcomes were the 10-meter walking test (10 MWT), the Walking Index for Spinal Cord Injury (WISCI II), the six-meter walking test (6 MWT), the Timed Up and Go test (TUG) and the Lower Extremity Motor Scores (LEMS). Secondary outcomes were spatiotemporal and kinematics measures. All participants were tested before, during, and after training and at 8 weeks follow-up. Participants experienced significant improvements in walking speed (0.06 m/s, p = 0.008), distance (29 m, p = 0.005), TUG (3.4 s, p = 0.012), LEMS (3.4, p = 0.017) and WISCI after eight weeks of training with LOPES. At the eight-week follow-up, participants retained the improvements measured at the end of the training period. Significant improvements were also found in spatiotemporal measures and hip range of motion. Robotic gait training using an impedance-controlled robot is feasible in gait

An integrated gait rehabilitation training based on Functional Electrical Stimulation cycling and overground robotic exoskeleton in complete spinal cord injury patients: Preliminary results.

Science.gov (United States)

Mazzoleni, S; Battini, E; Rustici, A; Stampacchia, G

2017-07-01

The aim of this study is to investigate the effects of an integrated gait rehabilitation training based on Functional Electrical Stimulation (FES)-cycling and overground robotic exoskeleton in a group of seven complete spinal cord injury patients on spasticity and patient-robot interaction. They underwent a robot-assisted rehabilitation training based on two phases: n=20 sessions of FES-cycling followed by n= 20 sessions of robot-assisted gait training based on an overground robotic exoskeleton. The following clinical outcome measures were used: Modified Ashworth Scale (MAS), Numerical Rating Scale (NRS) on spasticity, Penn Spasm Frequency Scale (PSFS), Spinal Cord Independence Measure Scale (SCIM), NRS on pain and International Spinal Cord Injury Pain Data Set (ISCI). Clinical outcome measures were assessed before (T0) after (T1) the FES-cycling training and after (T2) the powered overground gait training. The ability to walk when using exoskeleton was assessed by means of 10 Meter Walk Test (10MWT), 6 Minute Walk Test (6MWT), Timed Up and Go test (TUG), standing time, walking time and number of steps. Statistically significant changes were found on the MAS score, NRS-spasticity, 6MWT, TUG, standing time and number of steps. The preliminary results of this study show that an integrated gait rehabilitation training based on FES-cycling and overground robotic exoskeleton in complete SCI patients can provide a significant reduction of spasticity and improvements in terms of patient-robot interaction.

Effects of Robot-assisted Gait Training Combined with Functional Electrical Stimulation on Recovery of Locomotor Mobility in Chronic Stroke Patients: A Randomized Controlled Trial.

Science.gov (United States)

Bae, Young-Hyeon; Ko, Young Jun; Chang, Won Hyuk; Lee, Ju Hyeok; Lee, Kyeong Bong; Park, Yoo Jung; Ha, Hyun Geun; Kim, Yun-Hee

2014-12-01

[Purpose] The purpose of the present study was to investigate the effects of robot-assisted gait training combined with functional electrical stimulation on locomotor recovery in patients with chronic stroke. [Subjects] The 20 subjects were randomly assigned into either an experimental group (n = 10) that received a combination of robot-assisted gait training and functional electrical stimulation on the ankle dorsiflexor of the affected side or a control group (n = 10) that received robot-assisted gait training only. [Methods] Both groups received the respective therapies for 30 min/day, 3 days/week for 5 weeks. The outcome was measured using the Modified Motor Assessment Scale (MMAS), Timed Up-and-Go Test (TUG), Berg Balance Scale (BBS), and gait parameters through gait analysis (Vicon 370 motion analysis system, Oxford Metrics Ltd., Oxford, UK). All the variables were measured before and after training. [Results] Step length and maximal knee extension were significantly greater than those before training in the experimental group only. Maximal Knee flexion showed a significant difference between the experimental and control groups. The MMAS, BBS, and TUG scores improved significantly after training compared with before training in both groups. [Conclusion] We suggest that the combination of robot-assisted gait training and functional electrical stimulation encourages patients to actively participate in training because it facilitates locomotor recovery without the risk of adverse effects.

Effect of an ankle-foot orthosis on knee joint mechanics: a novel conservative treatment for knee osteoarthritis.

Science.gov (United States)

Fantini Pagani, Cynthia H; Willwacher, Steffen; Benker, Rita; Brüggemann, Gert-Peter

2014-12-01

Several conservative treatments for medial knee osteoarthritis such as knee orthosis and laterally wedged insoles have been shown to reduce the load in the medial knee compartment. However, those treatments also present limitations such as patient compliance and inconsistent results regarding the treatment success. To analyze the effect of an ankle-foot orthosis on the knee adduction moment and knee joint alignment in the frontal plane in subjects with knee varus alignment. Controlled laboratory study, repeated measurements. In total, 14 healthy subjects with knee varus alignment were analyzed in five different conditions: without orthotic, with laterally wedged insoles, and with an ankle-foot orthosis in three different adjustments. Three-dimensional kinetic and kinematic data were collected during gait analysis. Significant decreases in knee adduction moment, knee lever arm, and joint alignment in the frontal plane were observed with the ankle-foot orthosis in all three different adjustments. No significant differences could be found in any parameter while using the laterally wedged insoles. The ankle-foot orthosis was effective in reducing the knee adduction moment. The decreases in this parameter seem to be achieved by changing the knee joint alignment and thereby reducing the knee lever arm in the frontal plane. This study presents a novel approach for reducing the load in the medial knee compartment, which could be developed as a new treatment option for patients with medial knee osteoarthritis. © The International Society for Prosthetics and Orthotics 2013.

Volition-adaptive control for gait training using wearable exoskeleton: preliminary tests with incomplete spinal cord injury individuals.

Science.gov (United States)

Rajasekaran, Vijaykumar; López-Larraz, Eduardo; Trincado-Alonso, Fernando; Aranda, Joan; Montesano, Luis; Del-Ama, Antonio J; Pons, Jose L

2018-01-03

Gait training for individuals with neurological disorders is challenging in providing the suitable assistance and more adaptive behaviour towards user needs. The user specific adaptation can be defined based on the user interaction with the orthosis and by monitoring the user intentions. In this paper, an adaptive control model, commanded by the user intention, is evaluated using a lower limb exoskeleton with incomplete spinal cord injury individuals (SCI). A user intention based adaptive control model has been developed and evaluated with 4 incomplete SCI individuals across 3 sessions of training per individual. The adaptive control model modifies the joint impedance properties of the exoskeleton as a function of the human-orthosis interaction torques and the joint trajectory evolution along the gait sequence, in real time. The volitional input of the user is identified by monitoring the neural signals, pertaining to the user's motor activity. These volitional inputs are used as a trigger to initiate the gait movement, allowing the user to control the initialization of the exoskeleton movement, independently. A Finite-state machine based control model is used in this set-up which helps in combining the volitional orders with the gait adaptation. The exoskeleton demonstrated an adaptive assistance depending on the patients' performance without guiding them to follow an imposed trajectory. The exoskeleton initiated the trajectory based on the user intention command received from the brain machine interface, demonstrating it as a reliable trigger. The exoskeleton maintained the equilibrium by providing suitable assistance throughout the experiments. A progressive change in the maximum flexion of the knee joint was observed at the end of each session which shows improvement in the patient performance. Results of the adaptive impedance were evaluated by comparing with the application of a constant impedance value. Participants reported that the movement of the

A new approach to implement a customized anatomic insole in orthopaedic footwear of lower limb orthosis

Science.gov (United States)

Peixoto, J.; Flores, P.; Souto, A. P.

2017-10-01

This paper concerns the development of a new approach for orthopaedic footwear to apply in KAFO orthosis (acronym for Knee Ankle Foot Orthosis). This procedure starts with full characterization of the problem with the purpose to characterize a plantar of a patient’s foot with polio. A 3D Scanner was used to collect their feet’s data to produce an anatomic insole. After this step, the patient performs a study of his gait using a static and dynamic study with the aim of characterizing the parameters to improve quality in the footwear. The insole was produced using a 3D printing technology. It was essential to optimize manufacturing processes and it was developed a footwear prototype with innovative characteristics, which is 25% lighter, allowing the user to consume less energy in daily routines.

Torque Control of Underactuated Tendon-driven Robotic Fingers

Science.gov (United States)

Abdallah, Muhammad E. (Inventor); Ihrke, Chris A. (Inventor); Reiland, Matthew J. (Inventor); Wampler, Charles W. (Inventor); Diftler, Myron A. (Inventor); Platt, Robert (Inventor); Bridgwater, Lyndon (Inventor)

2013-01-01

A robotic system includes a robot having a total number of degrees of freedom (DOF) equal to at least n, an underactuated tendon-driven finger driven by n tendons and n DOF, the finger having at least two joints, being characterized by an asymmetrical joint radius in one embodiment. A controller is in communication with the robot, and controls actuation of the tendon-driven finger using force control. Operating the finger with force control on the tendons, rather than position control, eliminates the unconstrained slack-space that would have otherwise existed. The controller may utilize the asymmetrical joint radii to independently command joint torques. A method of controlling the finger includes commanding either independent or parameterized joint torques to the controller to actuate the fingers via force control on the tendons.

Developing sensor-driven robots for hazardous environments

International Nuclear Information System (INIS)

Trivedi, M.M.; Gonzalez, R.C.; Abidi, M.A.

1987-01-01

Advancements in robotic technology are sought to provide enhanced personnel safety and reduced costs of operation associated with nuclear power plant manufacture, construction, maintenance, operation, and decommissioning. The authors describe main characteristics of advanced robotic systems for such applications and suggest utilization of sensor-driven robots. Research efforts described in the paper are directed towards developing robotic systems for automatic inspection and manipulation of various tasks associated with a test panel mounted with a variety of switches, controls, displays, meters, and valves

On extracting design principles from biology: II. Case study—the effect of knee direction on bipedal robot running efficiency

International Nuclear Information System (INIS)

Haberland, M; Kim, S

2015-01-01

Comparing the leg of an ostrich to that of a human suggests an important question to legged robot designers: should a robot's leg joint bend in the direction of running (‘forwards’) or opposite (‘backwards’)? Biological studies cannot answer this question for engineers due to significant differences between the biological and engineering domains. Instead, we investigated the inherent effect of joint bending direction on bipedal robot running efficiency by comparing energetically optimal gaits of a wide variety of robot designs sampled at random from a design space. We found that the great majority of robot designs have several locally optimal gaits with the knee bending backwards that are more efficient than the most efficient gait with the knee bending forwards. The most efficient backwards gaits do not exhibit lower touchdown losses than the most efficient forward gaits; rather, the improved efficiency of backwards gaits stems from lower torque and reduced motion at the hip. The reduced hip use of backwards gaits is enabled by the ability of the backwards knee, acting alone, to (1) propel the robot upwards and forwards simultaneously and (2) lift and protract the foot simultaneously. In the absence of other information, designers interested in building efficient bipedal robots with two-segment legs driven by electric motors should design the knee to bend backwards rather than forwards. Compared to common practices for choosing robot knee direction, application of this principle would have a strong tendency to improve robot efficiency and save design resources. (paper)

Insect-computer hybrid legged robot with user-adjustable speed, step length and walking gait.

Science.gov (United States)

Cao, Feng; Zhang, Chao; Choo, Hao Yu; Sato, Hirotaka

2016-03-01

We have constructed an insect-computer hybrid legged robot using a living beetle (Mecynorrhina torquata; Coleoptera). The protraction/retraction and levation/depression motions in both forelegs of the beetle were elicited by electrically stimulating eight corresponding leg muscles via eight pairs of implanted electrodes. To perform a defined walking gait (e.g., gallop), different muscles were individually stimulated in a predefined sequence using a microcontroller. Different walking gaits were performed by reordering the applied stimulation signals (i.e., applying different sequences). By varying the duration of the stimulation sequences, we successfully controlled the step frequency and hence the beetle's walking speed. To the best of our knowledge, this paper presents the first demonstration of living insect locomotion control with a user-adjustable walking gait, step length and walking speed. © 2016 The Author(s).

Combining environment-driven adaptation and task-driven optimisation in evolutionary robotics.

Science.gov (United States)

Haasdijk, Evert; Bredeche, Nicolas; Eiben, A E

2014-01-01

Embodied evolutionary robotics is a sub-field of evolutionary robotics that employs evolutionary algorithms on the robotic hardware itself, during the operational period, i.e., in an on-line fashion. This enables robotic systems that continuously adapt, and are therefore capable of (re-)adjusting themselves to previously unknown or dynamically changing conditions autonomously, without human oversight. This paper addresses one of the major challenges that such systems face, viz. that the robots must satisfy two sets of requirements. Firstly, they must continue to operate reliably in their environment (viability), and secondly they must competently perform user-specified tasks (usefulness). The solution we propose exploits the fact that evolutionary methods have two basic selection mechanisms-survivor selection and parent selection. This allows evolution to tackle the two sets of requirements separately: survivor selection is driven by the environment and parent selection is based on task-performance. This idea is elaborated in the Multi-Objective aNd open-Ended Evolution (monee) framework, which we experimentally validate. Experiments with robotic swarms of 100 simulated e-pucks show that monee does indeed promote task-driven behaviour without compromising environmental adaptation. We also investigate an extension of the parent selection process with a 'market mechanism' that can ensure equitable distribution of effort over multiple tasks, a particularly pressing issue if the environment promotes specialisation in single tasks.

Combining environment-driven adaptation and task-driven optimisation in evolutionary robotics.

Directory of Open Access Journals (Sweden)

Evert Haasdijk

Full Text Available Embodied evolutionary robotics is a sub-field of evolutionary robotics that employs evolutionary algorithms on the robotic hardware itself, during the operational period, i.e., in an on-line fashion. This enables robotic systems that continuously adapt, and are therefore capable of (re-adjusting themselves to previously unknown or dynamically changing conditions autonomously, without human oversight. This paper addresses one of the major challenges that such systems face, viz. that the robots must satisfy two sets of requirements. Firstly, they must continue to operate reliably in their environment (viability, and secondly they must competently perform user-specified tasks (usefulness. The solution we propose exploits the fact that evolutionary methods have two basic selection mechanisms-survivor selection and parent selection. This allows evolution to tackle the two sets of requirements separately: survivor selection is driven by the environment and parent selection is based on task-performance. This idea is elaborated in the Multi-Objective aNd open-Ended Evolution (monee framework, which we experimentally validate. Experiments with robotic swarms of 100 simulated e-pucks show that monee does indeed promote task-driven behaviour without compromising environmental adaptation. We also investigate an extension of the parent selection process with a 'market mechanism' that can ensure equitable distribution of effort over multiple tasks, a particularly pressing issue if the environment promotes specialisation in single tasks.

Tegotae-based decentralised control scheme for autonomous gait transition of snake-like robots.

Science.gov (United States)

Kano, Takeshi; Yoshizawa, Ryo; Ishiguro, Akio

2017-08-04

Snakes change their locomotion patterns in response to the environment. This ability is a motivation for developing snake-like robots with highly adaptive functionality. In this study, a decentralised control scheme of snake-like robots that exhibited autonomous gait transition (i.e. the transition between concertina locomotion in narrow aisles and scaffold-based locomotion on unstructured terrains) was developed. Additionally, the control scheme was validated via simulations. A key insight revealed is that these locomotion patterns were not preprogrammed but emerged by exploiting Tegotae, a concept that describes the extent to which a perceived reaction matches a generated action. Unlike local reflexive mechanisms proposed previously, the Tegotae-based feedback mechanism enabled the robot to 'selectively' exploit environments beneficial for propulsion, and generated reasonable locomotion patterns. It is expected that the results of this study can form the basis to design robots that can work under unpredictable and unstructured environments.

Design and Evaluation of a New Type of Knee Orthosis to Align the Mediolateral Angle of the Knee Joint with Osteoarthritis

Directory of Open Access Journals (Sweden)

Amir Esrafilian

2012-01-01

Full Text Available Background. Osteoarthritis (OA is a disease which influences the performance of the knee joint. Moreover, the force and moments applied on the joint increase in contrast to normal subjects. Various types of knee orthoses have been designed to solve the mentioned problems. However, there are other problems in terms of distal migration during walking and the alignment of the orthosis which cannot be changed following the use of brace. Therefore, the main aim of the research was to design an orthosis to solve the aforementioned problems. Method. A new type of knee orthosis was designed with a modular structure. Two patients with knee OA participated in this research project. The force applied on the foot, moment transmitted through the knee joint, and spatiotemporal gait parameters were measured by use of a motion analysis system. Results. The results of the research showed that the adduction moment applied on the knee joint decreased while subjects walked with the new knee orthosis (P-value < 0.05. Conclusion. The new design of the knee brace can be used as an effective treatment to decrease the loads applied on the knee joint and to improve the alignment whilst walking.

Immediate effects of using ankle-foot orthoses in the kinematics of gait and in the balance reactions in Charcot-Marie-Tooth disease

OpenAIRE

Pereira, Rouse Barbosa; Felício, Lílian Ramiro; Ferreira, Arthur de Sá; Menezes, Sara Lúcia de; Freitas, Marcos Raimundo Gomes de; Orsini, Marco

2014-01-01

The Charcot-Marie-Tooth (CMT) disease is a peripheral hereditary neuropathy with progressive distal muscle atrophy and weakness, mainly in lower limbs, that evolves limiting the gait and balance. The objective of the study was to analyse the immediate effects of using Ankle-Foot Orthosis (AFO) in the gait's kinematics and balance in patients with CMT. Nine individuals were evaluated by Tinetti scales and Dynamic Gait Index (DGI) and gait's kinematics parameters through the motion capturing sy...

Model Driven Software Development for Agricultural Robotics

DEFF Research Database (Denmark)

Larsen, Morten

The design and development of agricultural robots, consists of both mechan- ical, electrical and software components. All these components must be de- signed and combined such that the overall goal of the robot is fulfilled. The design and development of these systems require collaboration between...... processing, control engineering, etc. This thesis proposes a Model-Driven Software Develop- ment based approach to model, analyse and partially generate the software implementation of a agricultural robot. Furthermore, Guidelines for mod- elling the architecture of an agricultural robots are provided......, assisting with bridging the different engineering disciplines. Timing play an important role in agricultural robotic applications, synchronisation of robot movement and implement actions is important in order to achieve precision spraying, me- chanical weeding, individual feeding, etc. Discovering...

Rehabilitation of gait after stroke: a review towards a top-down approach

Science.gov (United States)

2011-01-01

This document provides a review of the techniques and therapies used in gait rehabilitation after stroke. It also examines the possible benefits of including assistive robotic devices and brain-computer interfaces in this field, according to a top-down approach, in which rehabilitation is driven by neural plasticity. The methods reviewed comprise classical gait rehabilitation techniques (neurophysiological and motor learning approaches), functional electrical stimulation (FES), robotic devices, and brain-computer interfaces (BCI). From the analysis of these approaches, we can draw the following conclusions. Regarding classical rehabilitation techniques, there is insufficient evidence to state that a particular approach is more effective in promoting gait recovery than other. Combination of different rehabilitation strategies seems to be more effective than over-ground gait training alone. Robotic devices need further research to show their suitability for walking training and their effects on over-ground gait. The use of FES combined with different walking retraining strategies has shown to result in improvements in hemiplegic gait. Reports on non-invasive BCIs for stroke recovery are limited to the rehabilitation of upper limbs; however, some works suggest that there might be a common mechanism which influences upper and lower limb recovery simultaneously, independently of the limb chosen for the rehabilitation therapy. Functional near infrared spectroscopy (fNIRS) enables researchers to detect signals from specific regions of the cortex during performance of motor activities for the development of future BCIs. Future research would make possible to analyze the impact of rehabilitation on brain plasticity, in order to adapt treatment resources to meet the needs of each patient and to optimize the recovery process. PMID:22165907

Rehabilitation of gait after stroke: a review towards a top-down approach

Directory of Open Access Journals (Sweden)

Belda-Lois Juan-Manuel

2011-12-01

Full Text Available Abstract This document provides a review of the techniques and therapies used in gait rehabilitation after stroke. It also examines the possible benefits of including assistive robotic devices and brain-computer interfaces in this field, according to a top-down approach, in which rehabilitation is driven by neural plasticity. The methods reviewed comprise classical gait rehabilitation techniques (neurophysiological and motor learning approaches, functional electrical stimulation (FES, robotic devices, and brain-computer interfaces (BCI. From the analysis of these approaches, we can draw the following conclusions. Regarding classical rehabilitation techniques, there is insufficient evidence to state that a particular approach is more effective in promoting gait recovery than other. Combination of different rehabilitation strategies seems to be more effective than over-ground gait training alone. Robotic devices need further research to show their suitability for walking training and their effects on over-ground gait. The use of FES combined with different walking retraining strategies has shown to result in improvements in hemiplegic gait. Reports on non-invasive BCIs for stroke recovery are limited to the rehabilitation of upper limbs; however, some works suggest that there might be a common mechanism which influences upper and lower limb recovery simultaneously, independently of the limb chosen for the rehabilitation therapy. Functional near infrared spectroscopy (fNIRS enables researchers to detect signals from specific regions of the cortex during performance of motor activities for the development of future BCIs. Future research would make possible to analyze the impact of rehabilitation on brain plasticity, in order to adapt treatment resources to meet the needs of each patient and to optimize the recovery process.

Skeletal and Clinical Effects of Exoskeleton-Assisted Gait

Science.gov (United States)

2015-10-01

robotic exoskeletons to enable gait in individuals with a complete spinal cord injury, the health benefits of exoskeleton -assisted gait have not been...for the use of robotic exoskeletons to enable gait in individuals with a complete spinal cord injury, clinical teams are not provided with...appropriate tools to estimate or predict potential health benefits (e.g. bone health) associated with exoskeleton -assisted gait. What was the impact on other

[Modern approach to gait restoration in patients in the acute period of cerebral stroke].

Science.gov (United States)

Skvortsova, V I; Ivanova, G E; Rumiantseva, N A; Staritsyn, A N; Kovrazhkina, E A; Suvorov, A Iu

2010-01-01

An objective of the study was to work out a complex program of gait restoration in patients with stroke using robot-driven mechanized gait trainers. The study included patients in the acute period of stroke (the mean age 59+/-10,4 years) who were not able to walk without assistance; 53 patients of the main group and 25 patients of the control group. The mean interval from the disease onset to the beginning of gait retraining sessions with mechanized gait trainers was 14+/-1,6 days depending on the adequacy of functional probes. The restoration program included everyday 30 minute sessions of exercise therapy. Patients of the main group received 20 min sessions using mechanized gait trainers Motomed Viva 2 and Gait Trainer 1 (GT1) with continuous monitoring of blood pressure and cardiac beat frequency. The number of sessions with GT1 was from 5 to 12, mean 7+/-1 sessions. After the complex restoration treatment, significant positive changes on scales of standing balance, functional categories of gait, Berg, Barthel (p< or =0.01) were observed in patients of the main group compared to controls. All patients of the main group became able to walk with a support or independently. The significant decrease (p< or =0.05) of a number of patients with disorders of proprioceptive sensitivity (from 37,7 to 9,4%) and with ataxia of the low extremities (from 37 to 11,3%) was observed in the main group, while no changes were seen in the control group. It has been concluded that the complex use of reflex kinesitherapy and robot-driven mechanotherapy in patients in the acute period of stroke allows to increase the functional activity and the level of self-service already prior to the discharge from hospital.

Using robot-applied resistance to augment body-weight-supported treadmill training in an individual with incomplete spinal cord injury.

Science.gov (United States)

Lam, Tania; Pauhl, Katherine; Krassioukov, Andrei; Eng, Janice J

2011-01-01

The efficacy of task-specific gait training for people with spinal cord injury (SCI) is premised on evidence that the provision of gait-related afferent feedback is key for the recovery of stepping movements. Recent findings have shown that sensory feedback from flexor muscle afferents can facilitate flexor muscle activity during the swing phase of walking. This case report was undertaken to determine the feasibility of using robot-applied forces to resist leg movements during body-weight-supported treadmill training (BWSTT) and to measure its effect on gait and other health-related outcomes. The patient described in this case report was a 43-year-old man with a T11 incomplete chronic SCI. He underwent 36 sessions of BWSTT using a robotic gait orthosis to provide forces that resist hip and knee flexion. Tolerance to the training program was monitored using the Borg CR10 scale and heart rate and blood pressure changes during each training session. Outcome measures (ie, 10-Meter Walk Test, Six-Minute Walk Test, modified Emory Functional Ambulation Profile [mEFAP], Activities-specific Balance Confidence Scale, and Canadian Occupational Performance Measure) were completed and kinematic parameters of gait, lower-extremity muscle strength (force-generating capacity), lower-limb girth, and tolerance to orthostatic stress were measured before and after the training program. The patient could tolerate the training. Overground walking speed, endurance, and performance on all subtasks of the mEFAP improved and were accompanied by increased lower-limb joint flexion and toe clearance during gait. The patient's ambulatory self-confidence and self-perceived performance in walking also improved. These findings suggest that this new approach to BWSTT is a feasible and potentially effective therapy for improving skilled overground walking performance.

A mechanized gait trainer for restoring gait in nonambulatory subjects.

Science.gov (United States)

Hesse, S; Uhlenbrock, D; Werner, C; Bardeleben, A

2000-09-01

To construct an advanced mechanized gait trainer to enable patients the repetitive practice of a gaitlike movement without overstraining therapists. DEVICE: Prototype gait trainer that simulates the phases of gait (by generating a ratio of 40% to 60% between swing and stance phases), supports the subjects according to their ability (lifts the foot during swing phase), and controls the center of mass in the vertical and horizontal directions. Two nonambulatory, hemiparetic patients who regained their walking ability after 4 weeks of daily training on the gait trainer, a 55-year-old woman and a 62-year-old man, both of whom had a first-time ischemic stroke. Four weeks of training, five times a week, each session 20 minutes long. Functional ambulation category (FAC, levels 0-5) to assess gait ability and ground level walking velocity. Rivermead motor assessment score (RMAS, 0-13) to assess gross motor function. Patient 1: At the end of treatment, she was able to walk independently on level ground with use of a walking stick. Her walking velocity had improved from .29m/sec to .59m/sec. Her RMAS score increased from 4 to 10, meaning she could walk at least 40 meters outside, pick up objects from floor, and climb stairs independently. Patient 2: At end of 4-week training, he could walk independently on even surfaces (FAC level 4), using an ankle-foot orthosis and a walking stick. His walking velocity improved from .14m/sec to .63m/sec. His RMAS increased from 3 to 10. The gait trainer enabled severely affected patients the repetitive practice of a gaitlike movement. Future studies may elucidate its value in gait rehabilitation of nonambulatory subjects.

How can push-off be preserved during use of an ankle foot orthosis in children with hemiplegia? A prospective controlled study.

Science.gov (United States)

Desloovere, Kaat; Molenaers, Guy; Van Gestel, Leen; Huenaerts, Catherine; Van Campenhout, Anja; Callewaert, Barbara; Van de Walle, Patricia; Seyler, J

2006-10-01

Several studies indicated that walking with an ankle foot orthosis (AFO) impaired third rocker. The purpose of this study was to evaluate the effects of two types of orthoses, with similar goal settings, on gait, in a homogeneous group of children, using both barefoot and shoe walking as control conditions. Fifteen children with hemiplegia, aged between 4 and 10 years, received two types of individually tuned AFOs: common posterior leaf-spring (PLS) and Dual Carbon Fiber Spring AFO (CFO) (with carbon fibre at the dorsal part of the orthosis). Both orthoses were expected to prevent plantar flexion, thus improving first rocker, allowing dorsiflexion to improve second rocker, absorbing energy during second rocker, and returning it during the third rocker. The effect of the AFOs was studied using objective gait analysis, including 3D kinematics, and kinetics in four conditions: barefoot, shoes without AFO, and PLS and CFO combined with shoes. Several gait parameters significantly changed in shoe walking compared to barefoot walking (cadence, ankle ROM and velocity, knee shock absorption, and knee angle in swing). The CFO produced a significantly larger ankle ROM and ankle velocity during push-off, and an increased plantar flexion moment and power generation at pre-swing compared to the PLS (<0.01). The results of this study further support the findings of previous studies indicating that orthoses improve specific gait parameters compared to barefoot walking (velocity, step length, first and second ankle rocker, sagittal knee and hip ROM). However, compared to shoes, not all improvements were statistically significant.

Modeling and Simulation of Wave Gait of a Hexapod Walking Robot: A CAD/CAE Approach

Directory of Open Access Journals (Sweden)

Abhijit Mahapatra

2013-03-01

Full Text Available In the present paper, an attempt has been made to carry out dynamic analysis of a hexapod robot using the concept of multibody dynamics. A CAD (Computer Aided Design model of a realistic hexapod robot has been made for dynamic simulation of its locomotion using ADAMS (Automatic Dynamic Analysis of Mechanical Systems multibody dynamics solver. The kinematic model of each leg of three degrees of freedom has been designed using CATIA (Computer Aided Three Dimensional Interactive Application and SimDesigner package in order to develop an overall kinematic model of the robot, when it follows a straight path. Joint Torque variation as well as the variation of the aggregate center of mass of the robot was analyzed for the wave tetrapod gait. The simulation results provide the basis for developing the control algorithm as well as an intelligent decision making for the robot while in motion.

Exoskeleton Technology in Rehabilitation: Towards an EMG-Based Orthosis System for Upper Limb Neuromotor Rehabilitation

Directory of Open Access Journals (Sweden)

Luis Manuel Vaca Benitez

2013-01-01

Full Text Available The rehabilitation of patients should not only be limited to the first phases during intense hospital care but also support and therapy should be guaranteed in later stages, especially during daily life activities if the patient’s state requires this. However, aid should only be given to the patient if needed and as much as it is required. To allow this, automatic self-initiated movement support and patient-cooperative control strategies have to be developed and integrated into assistive systems. In this work, we first give an overview of different kinds of neuromuscular diseases, review different forms of therapy, and explain possible fields of rehabilitation and benefits of robotic aided rehabilitation. Next, the mechanical design and control scheme of an upper limb orthosis for rehabilitation are presented. Two control models for the orthosis are explained which compute the triggering function and the level of assistance provided by the device. As input to the model fused sensor data from the orthosis and physiology data in terms of electromyography (EMG signals are used.

Effect of ankle-foot orthoses on walking efficiency and gait in children with cerebral palsy

NARCIS (Netherlands)

Brehm, M.A.; Harlaar, J.; Schwartz, M.

2008-01-01

Objective: To determine the effect of ankle-foot orthoses on walking efficiency and gait in a heterogeneous group of children with cerebral palsy, using barefoot walking as the control condition. Design: A retrospective study. Methods: Barefoot and ankle-foot orthosis data for 172 children with

Hemorrhagic versus ischemic stroke: Who can best benefit from blended conventional physiotherapy with robotic-assisted gait therapy?

Directory of Open Access Journals (Sweden)

Frédéric Dierick

Full Text Available Contrary to common belief of clinicians that hemorrhagic stroke survivors have better functional prognoses than ischemic, recent studies show that ischemic survivors could experience similar or even better functional improvements. However, the influence of stroke subtype on gait and posture outcomes following an intervention blending conventional physiotherapy with robotic-assisted gait therapy is missing.This study compared gait and posture outcome measures between ambulatory hemorrhagic patients and ischemic patients, who received a similar 4 weeks' intervention blending a conventional bottom-up physiotherapy approach and an exoskeleton top-down robotic-assisted gait training (RAGT approach with Lokomat.Forty adult hemiparetic stroke inpatient subjects were recruited: 20 hemorrhagic and 20 ischemic, matched by age, gender, side of hemisphere lesion, stroke severity, and locomotor impairments. Functional Ambulation Category, Postural Assessment Scale for Stroke, Tinetti Performance Oriented Mobility Assessment, 6 Minutes Walk Test, Timed Up and Go and 10-Meter Walk Test were performed before and after a 4-week long intervention. Functional gains were calculated for all tests.Hemorrhagic and ischemic subjects showed significant improvements in Functional Ambulation Category (P<0.001 and P = 0.008, respectively, Postural Assessment Scale for Stroke (P<0.001 and P = 0.003, 6 Minutes Walk Test (P = 0.003 and P = 0.015 and 10-Meter Walk Test (P = 0.001 and P = 0.024. Ischemic patients also showed significant improvements in Timed Up and Go. Significantly greater mean Functional Ambulation Category and Tinetti Performance Oriented Mobility Assessment gains were observed for hemorrhagic compared to ischemic, with large (dz = 0.81 and medium (dz = 0.66 effect sizes, respectively.Overall, both groups exhibited quasi similar functional improvements and benefits from the same type, length and frequency of blended conventional physiotherapy and RAGT

Bra.Di.P.O. and P.I.G.R.O.: Innovative Devices for Motor Learning Programs

Directory of Open Access Journals (Sweden)

Guido Belforte

2014-01-01

Full Text Available Two mechatronics prototypes, useful for robotic neurotreatments and new clinical trainings, are here presented. P.I.G.R.O. (pneumatic interactive gait rehabilitation orthosis is an active exoskeleton with an electropneumatic control. It imposes movements on lower limbs in order to produce in the patient’s brain proper motor cortex activation. Bra.Di.P.O. (brain discovery pneumatic orthosis is an MR-compatible device, designed to improve fMRI (functional magnetic resonance imaging analysis. The two devices are presented together because both are involved in the study of new robotic treatments of patients affected by ictus or brain stroke or in some motor learning experimental investigations carried out on healthy subjects.

Reshaping of Gait Coordination by Robotic Intervention in Myelopathy Patients After Surgery

Science.gov (United States)

Puentes, Sandra; Kadone, Hideki; Kubota, Shigeki; Abe, Tetsuya; Shimizu, Yukiyo; Marushima, Aiki; Sankai, Yoshiyuki; Yamazaki, Masashi; Suzuki, Kenji

2018-01-01

The Ossification of the Posterior Longitudinal Ligament (OPLL) is an idiopathic degenerative spinal disease which may cause motor deficit. For patients presenting myelopathy or severe stenosis, surgical decompression is the treatment of choice; however, despite adequate decompression residual motor impairment is found in some cases. After surgery, there is no therapeutic approach available for this population. The Hybrid Assistive Limb® (HAL) robot suit is a unique powered exoskeleton designed to predict, support, and enhance the lower extremities performance of patients using their own bioelectric signals. This approach has been used for spinal cord injury and stroke patients where the walking performance improved. However, there is no available data about gait kinematics evaluation after HAL therapy. Here we analyze the effect of HAL therapy in OPLL patients in acute and chronic stages after decompression surgery. We found that HAL therapy improved the walking performance for both groups. Interestingly, kinematics evaluation by the analysis of the elevation angles of the thigh, shank, and foot by using a principal component analysis showed that planar covariation, plane orientation, and movement range evaluation improved for acute patients suggesting an improvement in gait coordination. Being the first study performing kinematics analysis after HAL therapy, our results suggest that HAL improved the gait coordination of acute patients by supporting the relearning process and therefore reshaping their gait pattern. PMID:29551960

A Comparative Study of Biologically Inspired Walking Gaits through Waypoint Navigation

Directory of Open Access Journals (Sweden)

Umar Asif

2011-01-01

Full Text Available This paper investigates the locomotion of a walking robot by delivering a comparative study of three different biologically inspired walking gaits, namely: tripod, ripple, and wave, in terms of ground slippage they experience while walking. The objective of this study is to identify the gait model which experiences the minimum slippage while walking on a ground with a specific coefficient of friction. To accomplish this feat, the robot is steered over a reference path using a waypoint navigation algorithm, and the divergence of the robot from the reference path is investigated in terms of slip errors. Experiments are conducted through closed-loop simulations using an open dynamics engine which emphasizes the fact that due to uneven and unsymmetrical distribution of payload in tripod and ripple gait models, the robot experiences comparatively larger drift in these gaits than when using the wave gait model in which the distribution of payload is even and symmetrical on both sides of the robot body. The paper investigates this phenomenon on the basis of force distribution of supporting legs in each gait model.

Gait-Cycle-Driven Transmission Power Control Scheme for a Wireless Body Area Network.

Science.gov (United States)

Zang, Weilin; Li, Ye

2018-05-01

In a wireless body area network (WBAN), walking movements can result in rapid channel fluctuations, which severely degrade the performance of transmission power control (TPC) schemes. On the other hand, these channel fluctuations are often periodic and are time-synchronized with the user's gait cycle, since they are all driven from the walking movements. In this paper, we propose a novel gait-cycle-driven transmission power control (G-TPC) for a WBAN. The proposed G-TPC scheme reinforces the existing TPC scheme by exploiting the periodic channel fluctuation in the walking scenario. In the proposed scheme, the user's gait cycle information acquired by an accelerometer is used as beacons for arranging the transmissions at the time points with the ideal channel state. The specific transmission power is then determined by using received signal strength indication (RSSI). An experiment was conducted to evaluate the energy efficiency and reliability of the proposed G-TPC based on a CC2420 platform. The results reveal that compared to the original RSSI/link-quality-indication-based TPC, G-TPC reduces energy consumption by 25% on the sensor node and reduce the packet loss rate by 65%.

Design of Spiking Central Pattern Generators for Multiple Locomotion Gaits in Hexapod Robots by Christiansen Grammar Evolution.

Science.gov (United States)

Espinal, Andres; Rostro-Gonzalez, Horacio; Carpio, Martin; Guerra-Hernandez, Erick I; Ornelas-Rodriguez, Manuel; Sotelo-Figueroa, Marco

2016-01-01

This paper presents a method to design Spiking Central Pattern Generators (SCPGs) to achieve locomotion at different frequencies on legged robots. It is validated through embedding its designs into a Field-Programmable Gate Array (FPGA) and implemented on a real hexapod robot. The SCPGs are automatically designed by means of a Christiansen Grammar Evolution (CGE)-based methodology. The CGE performs a solution for the configuration (synaptic weights and connections) for each neuron in the SCPG. This is carried out through the indirect representation of candidate solutions that evolve to replicate a specific spike train according to a locomotion pattern (gait) by measuring the similarity between the spike trains and the SPIKE distance to lead the search to a correct configuration. By using this evolutionary approach, several SCPG design specifications can be explicitly added into the SPIKE distance-based fitness function, such as looking for Spiking Neural Networks (SNNs) with minimal connectivity or a Central Pattern Generator (CPG) able to generate different locomotion gaits only by changing the initial input stimuli. The SCPG designs have been successfully implemented on a Spartan 6 FPGA board and a real time validation on a 12 Degrees Of Freedom (DOFs) hexapod robot is presented.

Robot-Assisted Body-Weight-Supported Treadmill Training in Gait Impairment in Multiple Sclerosis Patients: A Pilot Study.

Science.gov (United States)

Łyp, Marek; Stanisławska, Iwona; Witek, Bożena; Olszewska-Żaczek, Ewelina; Czarny-Działak, Małgorzata; Kaczor, Ryszard

2018-02-13

This study deals with the use of a robot-assisted body-weight-supported treadmill training in multiple sclerosis (MS) patients with gait dysfunction. Twenty MS patients (10 men and 10 women) of the mean of 46.3 ± 8.5 years were assigned to a six-week-long training period with the use of robot-assisted treadmill training of increasing intensity of the Lokomat type. The outcome measure consisted of the difference in motion-dependent torque of lower extremity joint muscles after training compared with baseline before training. We found that the training uniformly and significantly augmented the torque of both extensors and flexors of the hip and knee joints. The muscle power in the lower limbs of SM patients was improved, leading to corrective changes of disordered walking movements, which enabled the patients to walk with less effort and less assistance of care givers. The torque augmentation could have its role in affecting the function of the lower extremity muscle groups during walking. The results of this pilot study suggest that the robot-assisted body-weight-supported treadmill training may be a potential adjunct measure in the rehabilitation paradigm of 'gait reeducation' in peripheral neuropathies.

[Robotic systems for gait re-education in cases of spinal cord injury: a systematic review].

Science.gov (United States)

Gandara-Sambade, T; Fernandez-Pereira, M; Rodriguez-Sotillo, A

2017-03-01

The evidence underlying robotic body weight supported treadmill training in patients with spinal cord injury remains poorly characterized. To perform a qualitative systematic review on the efficacy of this therapy. A search on PubMed, CINAHL, Cochrane Library and PEDro was performed from January 2005 to April 2016. The references in these articles were also reviewed to find papers not identified with the initial search strategy. The methodological level of the articles was evaluated with PEDro and Downs and Black scales. A total of 129 potentially interesting articles were found, of which 10 fulfilled the inclusion criteria. Those studies included 286 patients, who were predominantly young and male. Most of them had an incomplete spinal cord injury and were classified as C or D in ASIA scale. Robotic devices employed in these studies were Lokomat, Gait Trainer and LOPES. Improvement in walking parameters evaluated was more evident in young patients, those with subacute spinal cord injury, and those with high ASIA or LEMS scores. Conversely, factors such as etiology, level of injury or sex were less predictive of improvement. The methodological level of these studies was fair according to PEDro and Downs and Black scales. The evidence of gait training with robotic devices in patients with spinal cord injury is positive, although limited and with fair methodological quality.

Clinical application of the modified medially-mounted motor-driven hip gear joint for paraplegics.

Science.gov (United States)

Sonoda, S; Imahori, R; Saitoh, E; Tomita, Y; Domen, K; Chino, N

2000-04-15

This paper describes a motor-driven orthosis for paraplegics which has been developed. This orthosis is composed of a medially-mounted motor-driven hip joint and bilateral knee-ankle-foot orthosis. With the gear mechanism, the virtual axis of the hip joint of this orthosis is almost as high as the anatomical hip joint. A paraplegic patient with an injury level of T10/11 walked using bilateral lofstrand crutches and this new orthosis with or without the motor system. The motor is initiated by pushing a button attached at the edge of the grab of the crutches. Faster cadence and speed and smaller rotation angle of the trunk was obtained in motor walking compared with non-motor walking. The patient did not feel fearful of falling. The benefit of motor orthosis is that it can be used even in patients with lower motor lesions and that it provides stable regulation of hip flexion movement in spastic patients. In conclusion, this motor orthosis will enhance paraplegic walking.

Robotic Gait Training for Individuals With Cerebral Palsy: A Systematic Review and Meta-Analysis.

Science.gov (United States)

Carvalho, Igor; Pinto, Sérgio Medeiros; Chagas, Daniel das Virgens; Praxedes Dos Santos, Jomilto Luiz; de Sousa Oliveira, Tainá; Batista, Luiz Alberto

2017-11-01

To identify the effects of robotic gait training practices in individuals with cerebral palsy. The search was performed in the following electronic databases: PubMed, Embase, Medline (OvidSP), Cochrane Database of Systematic Reviews, Web of Science, Scopus, Compendex, IEEE Xplore, ScienceDirect, Academic Search Premier, and Physiotherapy Evidence Database. Studies were included if they fulfilled the following criteria: (1) they investigated the effects of robotic gait training, (2) they involved patients with cerebral palsy, and (3) they enrolled patients classified between levels I and IV using the Gross Motor Function Classification System. The information was extracted from the selected articles using the descriptive-analytical method. The Critical Review Form for Quantitative Studies was used to quantitate the presence of critical components in the articles. To perform the meta-analysis, the effects of the intervention were quantified by effect size (Cohen d). Of the 133 identified studies, 10 met the inclusion criteria. The meta-analysis showed positive effects on gait speed (.21 [-.09, .51]), endurance (.21 [-.06, .49]), and gross motor function in dimension D (.18 [-.10, .45]) and dimension E (0.12 [-.15, .40]). The results obtained suggest that this training benefits people with cerebral palsy, specifically by increasing walking speed and endurance and improving gross motor function. For future studies, we suggest investigating device configuration parameters and conducting a large number of randomized controlled trials with larger sample sizes and individuals with homogeneous impairment. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

The effect of 'device-in-charge' support during robotic gait training on walking ability and balance in chronic stroke survivors: A systematic review

NARCIS (Netherlands)

Haarman, Juliet Albertina Maria; Reenalda, Jasper; Buurke, Jaap; van der Kooij, Herman; Rietman, Johan Swanik

2016-01-01

This review describes the effects of two control strategies – used in robotic gait-training devices for chronic stroke survivors – on gait speed, endurance and balance. Control strategies are classified as ‘patient-in-charge support’, where the device ‘empowers’ the patient, and ‘device-in-charge

Rendering potential wearable robot designs with the LOPES gait trainer.

Science.gov (United States)

Koopman, B; van Asseldonk, E H F; van der Kooij, H; van Dijk, W; Ronsse, R

2011-01-01

In recent years, wearable robots (WRs) for rehabilitation, personal assistance, or human augmentation are gaining increasing interest. To make these devices more energy efficient, radical changes to the mechanical structure of the device are being considered. However, it remains very difficult to predict how people will respond to, and interact with, WRs that differ in terms of mechanical design. Users may adjust their gait pattern in response to the mechanical restrictions or properties of the device. The goal of this pilot study is to show the feasibility of rendering the mechanical properties of different potential WR designs using the robotic gait training device LOPES. This paper describes a new method that selectively cancels the dynamics of LOPES itself and adds the dynamics of the rendered WR using two parallel inverse models. Adaptive frequency oscillators were used to get estimates of the joint position, velocity, and acceleration. Using the inverse models, different WR designs can be evaluated, eliminating the need to build several prototypes. As a proof of principle, we simulated the effect of a very simple WR that consisted of a mass attached to the ankles. Preliminary results show that we are partially able to cancel the dynamics of LOPES. Additionally, the simulation of the mass showed an increase in muscle activity but not in the same level as during the control, where subjects actually carried the mass. In conclusion, the results in this paper suggest that LOPES can be used to render different WRs. In addition, it is very likely that the results can be further optimized when more effort is put in retrieving proper estimations for the velocity and acceleration, which are required for the inverse models. © 2011 IEEE

Design and Analysis of a Bio-Inspired Wire-Driven Multi-Section Flexible Robot

Directory of Open Access Journals (Sweden)

Zheng Li

2013-04-01

Full Text Available This paper presents a bio-inspired wire-driven multi-section flexible robot. It is inspired by the snake skeleton and octopus arm muscle arrangements. The robot consists of three sections and each section is made up of several identical vertebras, which are articulated by both spherical joints and a flexible backbone. Each section is driven by two groups of wires, controlling the bending motion in X and Y directions. This design integrates the serpentine robots' structure and the continuum robots' actuation. As a result, it is more compact than traditional serpentine robots and has a higher positioning accuracy than typical continuum soft robots, such as OctArm V. A Kinematics model and a workspace model of the robot are developed based on the piece wise constant curvature assumption. To evaluate the design, a prototype is built and experiments are carried out. The average distal end positioning error is less than 4%. Characteristics of the wire-driven robot are also discussed, including the leverage effect and the manipulability under constraint. These features makes the proposed robot well suited to confined spaces, especially for working in minimally invasive surgery, nuclear reactor pipelines, disaster debris, etc.

Slow walking model for children with multiple disabilities via an application of humanoid robot

Science.gov (United States)

Wang, ZeFeng; Peyrodie, Laurent; Cao, Hua; Agnani, Olivier; Watelain, Eric; Wang, HaoPing

2016-02-01

Walk training research with children having multiple disabilities is presented. Orthosis aid in walking for children with multiple disabilities such as Cerebral Palsy continues to be a clinical and technological challenge. In order to reduce pain and improve treatment strategies, an intermediate structure - humanoid robot NAO - is proposed as an assay platform to study walking training models, to be transferred to future special exoskeletons for children. A suitable and stable walking model is proposed for walk training. It would be simulated and tested on NAO. This comparative study of zero moment point (ZMP) supports polygons and energy consumption validates the model as more stable than the conventional NAO. Accordingly direction variation of the center of mass and the slopes of linear regression knee/ankle angles, the Slow Walk model faithfully emulates the gait pattern of children.

Development of an Active Ankle Foot Orthosis to Prevent Foot Drop and Toe Drag in Hemiplegic Patients: A Preliminary Study

Directory of Open Access Journals (Sweden)

Jungyoon Kim

2011-01-01

Full Text Available We developed an active ankle-foot orthosis (AAFO that controls dorsiflexion/plantarflexion of the ankle joint to prevent foot drop and toe drag during hemiplegic walking. To prevent foot slap after initial contact, the ankle joint must remain active to minimize forefoot collision against the ground. During late stance, the ankle joint must also remain active to provide toe clearance and to aid with push-off. We implemented a series elastic actuator in our AAFO to induce ankle dorsiflexion/plantarflexion. The activator was controlled by signals from force sensing register (FSR sensors that detected gait events. Three dimensional gait analyses were performed for three hemiplegic patients under three different gait conditions: gait without AFO (NAFO, gait with a conventional hinged AFO that did not control the ankle joint (HAFO, and gait with the newly-developed AFO (AAFO. Our results demonstrate that our newly-developed AAFO not only prevents foot drop by inducing plantarflexion during loading response, but also prevents toe drag by facilitating plantarflexion during pre-swing and dorsiflexion during swing phase, leading to improvement in most temporal-spatial parameters. However, only three hemiplegic patients were included in this gait analysis. Studies including more subjects will be required to evaluate the functionality of our newly developed AAFO.

Foot trajectory approximation using the pendulum model of walking.

Science.gov (United States)

Fang, Juan; Vuckovic, Aleksandra; Galen, Sujay; Conway, Bernard A; Hunt, Kenneth J

2014-01-01

Generating a natural foot trajectory is an important objective in robotic systems for rehabilitation of walking. Human walking has pendular properties, so the pendulum model of walking has been used in bipedal robots which produce rhythmic gait patterns. Whether natural foot trajectories can be produced by the pendulum model needs to be addressed as a first step towards applying the pendulum concept in gait orthosis design. This study investigated circle approximation of the foot trajectories, with focus on the geometry of the pendulum model of walking. Three able-bodied subjects walked overground at various speeds, and foot trajectories relative to the hip were analysed. Four circle approximation approaches were developed, and best-fit circle algorithms were derived to fit the trajectories of the ankle, heel and toe. The study confirmed that the ankle and heel trajectories during stance and the toe trajectory in both the stance and the swing phases during walking at various speeds could be well modelled by a rigid pendulum. All the pendulum models were centred around the hip with pendular lengths approximately equal to the segment distances from the hip. This observation provides a new approach for using the pendulum model of walking in gait orthosis design.

The influence of ankle joint mobility when using an orthosis on stability in patients with spinal cord injury: a pilot study.

Science.gov (United States)

Arazpour, M; Bani, M A; Hutchins, S W; Curran, S; Javanshir, M A

2013-10-01

Perceived risk of falling is an important factor for people with spinal cord injury (SCI). This study investigated the influence of ankle joint motion on postural stability and walking in people with SCI when using an orthosis. Volunteer subjects with SCI (n=5) participated in this study. Each subject was fitted with an advanced reciprocating gait orthosis (ARGO) equipped with either solid or dorsiflexion-assist type ankle-foot orthosis (AFOs) and walked at their self-selected speed along a flat walkway to enable the comparison of walking speed, cadence and endurance. A force plate system and a modified Falls Efficacy Scale (MFES) were utilized to measure postural sway and the perceived fear of falling, respectively. There were significant differences in the mean MFES scores between two types of orthosis (P=0.023). When using two crutches, there was no significant difference in static standing postural sway in the medio-lateral (M/L) direction (P=0.799), but significant difference in the antero-posterior (A/P) direction (P=0.014). However, during single crutch support, there was a significant difference in both M/L (P=0.019) and A/P (P=0.022) directions. Walking speed (7%) and endurance (5%) significantly increased when using the ARGO with dorsi flexion assisted AFOs. There was no significant deference between two types of orthoses in cadence (P=0.54). Using an ARGO with dorsiflexion-assisted AFOs increased the fear of falling, but improved static postural stability and increased walking speed and endurance, and should therefore be considered as an effective orthosis during the rehabilitation of people with SCI.

Internal Models Support Specific Gaits in Orthotic Devices

DEFF Research Database (Denmark)

Matthias Braun, Jan; Wörgötter, Florentin; Manoonpong, Poramate

2014-01-01

Patients use orthoses and prosthesis for the lower limbs to support and enable movements, they can not or only with difficulties perform themselves. Because traditional devices support only a limited set of movements, patients are restricted in their mobility. A possible approach to overcome such...... the system's accuracy and robustness on a Knee-Ankle-Foot-Orthosis, introducing behaviour changes depending on the patient's current walking situation. We conclude that the here presented model-based support of different gaits has the power to enhance the patient's mobility....

An online gait generator for quadruped walking using motor primitives

Directory of Open Access Journals (Sweden)

Chunlin Zhou

2016-11-01

Full Text Available This article presents implementation of an online gait generator on a quadruped robot. Firstly, the design of a quadruped robot is presented. The robot contains four leg modules each of which is constructed by a 2 degrees of freedom (2-DOF five-bar parallel linkage mechanism. Together with other two rotational DOF, the leg module is able to perform 4-DOF movement. The parallel mechanism of the robot allows all the servos attached on the body frame, so that the leg mass is decreased and motor load can be balanced. Secondly, an online gait generator based on dynamic movement primitives for the walking control is presented. Dynamic movement primitives provide an approach to generate periodic trajectories and they can be modulated in real time, which makes the online adjustment of walking gaits possible. This gait controller is tested by the quadruped robot in regulating walking speed, switching between forward\\backward movements and steering. The controller is easy to apply, expand and is quite effective on phase coordination and online trajectory modulation. Results of simulated experiments are presented.

Soft mobile robots driven by foldable dielectric elastomer actuators

Energy Technology Data Exchange (ETDEWEB)

Sun, Wenjie; Liu, Fan; Ma, Ziqi; Li, Chenghai; Zhou, Jinxiong, E-mail: jxzhouxx@mail.xjtu.edu.cn [State Key Laboratory for Strength and Vibration of Mechanical Structures and School of Aerospace, Xi' an Jiaotong University, Xi' an 710049 (China)

2016-08-28

A cantilever beam with elastic hinge pulled antagonistically by two dielectric elastomer (DE) membranes in tension forms a foldable actuator if one DE membrane is subject to a voltage and releases part of tension. Simply placing parallel rigid bars on the prestressed DE membranes results in enhanced actuators working in a pure shear state. We report design, analysis, fabrication, and experiment of soft mobile robots that are moved by such foldable DE actuators. We describe systematic measurement of the foldable actuators and perform theoretical analysis of such actuators based on minimization of total energy, and a good agreement is achieved between model prediction and measurement. We develop two versions of prototypes of soft mobile robots driven either by two sets of DE membranes or one DE membrane and elastic springs. We demonstrate locomotion of these soft mobile robots and highlight several key design parameters that influence locomotion of the robots. A 45 g soft robot driven by a cyclic triangle voltage with amplitude 7.4 kV demonstrates maximal stroke 160 mm or maximal rolling velocity 42 mm/s. The underlying mechanics and physics of foldable DE actuators can be leveraged to develop other soft machines for various applications.

The effects on Kinematics and Muscle Activity of Walking in a Robotic Gait Trainer During Zero-Force Control

NARCIS (Netherlands)

van Asseldonk, Edwin H.F.; Veneman, J.F.; Ekkelenkamp, R.; Buurke, Jaap; van der Helm, F.C.T.; van der Kooij, Herman

2008-01-01

“Assist as needed” control algorithms promote activity of patients during robotic gait training. Implementing these requires a free walking mode of a device, as unassisted motions should not be hindered. The goal of this study was to assess the normality of walking in the free walking mode of the

Magnetic fish-robot based on multi-motion control of a flexible magnetic actuator.

Science.gov (United States)

Kim, Sung Hoon; Shin, Kyoosik; Hashi, Shuichiro; Ishiyama, Kazushi

2012-09-01

This paper presents a biologically inspired fish-robot driven by a single flexible magnetic actuator with a rotating magnetic field in a three-axis Helmholtz coil. Generally, magnetic fish-robots are powered by alternating and gradient magnetic fields, which provide a single motion such as bending the fish-robot's fins. On the other hand, a flexible magnetic actuator driven by an external rotating magnetic field can create several gaits such as the bending vibration, the twisting vibration, and their combination. Most magnetic fish-like micro-robots do not have pectoral fins on the side and are simply propelled by the tail fin. The proposed robot can swim and perform a variety of maneuvers with the addition of pectoral fins and control of the magnetic torque direction. In this paper, we find that the robot's dynamic actuation correlates with the magnetic actuator and the rotating magnetic field. The proposed robot is also equipped with new features, such as a total of six degrees of freedom, a new control method that stabilizes posture, three-dimensional swimming, a new velocity control, and new turning abilities.

Magnetic fish-robot based on multi-motion control of a flexible magnetic actuator

International Nuclear Information System (INIS)

Kim, Sung Hoon; Hashi, Shuichiro; Ishiyama, Kazushi; Shin, Kyoosik

2012-01-01

This paper presents a biologically inspired fish-robot driven by a single flexible magnetic actuator with a rotating magnetic field in a three-axis Helmholtz coil. Generally, magnetic fish-robots are powered by alternating and gradient magnetic fields, which provide a single motion such as bending the fish-robot's fins. On the other hand, a flexible magnetic actuator driven by an external rotating magnetic field can create several gaits such as the bending vibration, the twisting vibration, and their combination. Most magnetic fish-like micro-robots do not have pectoral fins on the side and are simply propelled by the tail fin. The proposed robot can swim and perform a variety of maneuvers with the addition of pectoral fins and control of the magnetic torque direction. In this paper, we find that the robot's dynamic actuation correlates with the magnetic actuator and the rotating magnetic field. The proposed robot is also equipped with new features, such as a total of six degrees of freedom, a new control method that stabilizes posture, three-dimensional swimming, a new velocity control, and new turning abilities. (paper)

Design and Analysis of a Bio-Inspired Wire-Driven Multi-Section Flexible Robot

OpenAIRE

Li, Zheng; Du, Ruxu

2013-01-01

This paper presents a bio-inspired wire-driven multi-section flexible robot. It is inspired by the snake skeleton and octopus arm muscle arrangements. The robot consists of three sections and each section is made up of several identical vertebras, which are articulated by both spherical joints and a flexible backbone. Each section is driven by two groups of wires, controlling the bending motion in X and Y directions. This design integrates the serpentine robots' structure and the continuum ro...

Safety and efficacy of at-home robotic locomotion therapy in individuals with chronic incomplete spinal cord injury: a prospective, pre-post intervention, proof-of-concept study.

Directory of Open Access Journals (Sweden)

Rüdiger Rupp

Full Text Available The compact Motorized orthosis for home rehabilitation of Gait (MoreGait was developed for continuation of locomotion training at home. MoreGait generates afferent stimuli of walking with the user in a semi-supine position and provides feedback about deviations from the reference walking pattern.Prospective, pre-post intervention, proof-of-concept study to test the feasibility of an unsupervised home-based application of five MoreGait prototypes in subjects with incomplete spinal cord injury (iSCI.Twenty-five (5 tetraplegia, 20 paraplegia participants with chronic (mean time since injury: 5.8 ± 5.4 (standard deviation, SD years sensorimotor iSCI (7 ASIA Impairment Scale (AIS C, 18 AIS D; Walking Index for Spinal Cord Injury (WISCI II: Interquartile range 9 to 16 completed the training (45 minutes / day, at least 4 days / week, 8 weeks. Baseline status was documented 4 and 2 weeks before and at training onset. Training effects were assessed after 4 and 8 weeks of therapy.After therapy, 9 of 25 study participants improved with respect to the dependency on walking aids assessed by the WISCI II. For all individuals, the short-distance walking velocity measured by the 10-Meter Walk Test showed significant improvements compared to baseline (100% for both self-selected (Mean 139.4% ± 35.5% (SD and maximum (Mean 143.1% ± 40.6% (SD speed conditions as well as the endurance estimated with the six-minute walk test (Mean 166.6% ± 72.1% (SD. One device-related adverse event (pressure sore on the big toe occurred in over 800 training sessions.Home-based robotic locomotion training with MoreGait is feasible and safe. The magnitude of functional improvements achieved by MoreGait in individuals with iSCI is well within the range of complex locomotion robots used in hospitals. Thus, unsupervised MoreGait training potentially represents an option to prolong effective training aiming at recovery of locomotor function beyond in-patient rehabilitation

Immediate effects of a single session of robot-assisted gait training using Hybrid Assistive Limb (HAL) for cerebral palsy.

Science.gov (United States)

Matsuda, Mayumi; Mataki, Yuki; Mutsuzaki, Hirotaka; Yoshikawa, Kenichi; Takahashi, Kazushi; Enomoto, Keiko; Sano, Kumiko; Mizukami, Masafumi; Tomita, Kazuhide; Ohguro, Haruka; Iwasaki, Nobuaki

2018-02-01

[Purpose] Robot-assisted gait training (RAGT) using Hybrid Assistive Limb (HAL, CYBERDYNE) was previously reported beneficial for stroke and spinal cord injury patients. Here, we investigate the immediate effect of a single session of RAGT using HAL on gait function for cerebral palsy (CP) patients. [Subjects and Methods] Twelve patients (average age: 16.2 ± 7.3 years) with CP received a single session of RAGT using HAL. Gait speed, step length, cadence, single-leg support per gait cycle, hip and knee joint angle in stance, and swing phase per gait cycle were assessed before, during, and immediately after HAL intervention. [Results] Compared to baseline values, single-leg support per gait cycle (64.5 ± 15.8% to 69.3 ± 12.1%), hip extension angle in mid-stance (149.2 ± 19.0° to 155.5 ± 20.1°), and knee extension angle in mid-stance (137.6 ± 20.2° to 143.1 ± 19.5°) were significantly increased immediately after intervention. Further, the knee flexion angle in mid-swing was significantly decreased immediately after treatment (112.0 ± 15.5° to 105.2 ± 17.1°). Hip flexion angle in mid-swing also decreased following intervention (137.2 ± 14.6° to 129.7 ± 16.6°), but not significantly. Conversely, gait speed, step length, and cadence were unchanged after intervention. [Conclusion] A single-time RAGT with HAL improved single-leg support per gait cycle and hip and knee joint angle during gait, therapeutically improving gait function in CP patients.

Clinical practice guidelines for rest orthosis, knee sleeves, and unloading knee braces in knee osteoarthritis.

Science.gov (United States)

Beaudreuil, Johann; Bendaya, Samy; Faucher, Marc; Coudeyre, Emmanuel; Ribinik, Patricia; Revel, Michel; Rannou, François

2009-12-01

To develop clinical practice guidelines concerning the use of bracing--rest orthosis, knee sleeves and unloading knee braces--for knee osteoarthritis. The French Physical Medicine and Rehabilitation Society (SOFMER) methodology, associating a systematic literature review, collection of everyday clinical practice, and external review by multidisciplinary expert panel, was used. Few high-level studies of bracing for knee osteoarthritis were found. No evidence exists for the effectiveness of rest orthosis. Evidence for knee sleeves suggests that they decrease pain in knee osteoarthritis, and their use is associated with subjective improvement. These actions do not appear to depend on a local thermal effect. The effectiveness of knee sleeves for disability is not demonstrated for knee osteoarthritis. Short- and mid-term follow-up indicates that valgus knee bracing decreases pain and disability in medial knee osteoarthritis, appears to be more effective than knee sleeves, and improves quality of life, knee proprioception, quadriceps strength, and gait symmetry, and decreases compressive loads in the medial femoro-tibial compartment. However, results of response to valgus knee bracing remain inconsistent; discomfort and side effects can result. Thrombophlebitis of the lower limbs has been reported with the braces. Braces, whatever kind, are infrequently prescribed in clinical practice for osteoarthritis of the lower limbs. Modest evidence exists for the effectiveness of bracing--rest orthosis, knee sleeves and unloading knee braces--for knee osteoarthritis, with only low level recommendations for its use. Braces are prescribed infrequently in French clinical practice for osteoarthritis of the knee. Randomized clinical trials concerning bracing in knee osteoarthritis are still necessary.

Wrist Rehabilitation Assisted by an Electromyography-Driven Neuromuscular Electrical Stimulation Robot After Stroke.

Science.gov (United States)

Hu, Xiao-Ling; Tong, Raymond Kai-yu; Ho, Newmen S K; Xue, Jing-jing; Rong, Wei; Li, Leonard S W

2015-09-01

Augmented physical training with assistance from robot and neuromuscular electrical stimulation (NMES) may introduce intensive motor improvement in chronic stroke. To compare the rehabilitation effectiveness achieved by NMES robot-assisted wrist training and that by robot-assisted training. This study was a single-blinded randomized controlled trial with a 3-month follow-up. Twenty-six hemiplegic subjects with chronic stroke were randomly assigned to receive 20-session wrist training with an electromyography (EMG)-driven NMES robot (NMES robot group, n = 11) and with an EMG-driven robot (robot group, n = 15), completed within 7 consecutive weeks. Clinical scores, Fugl-Meyer Assessment (FMA), Modified Ashworth Score (MAS), and Action Research Arm Test (ARAT) were used to evaluate the training effects before and after the training, as well as 3 months later. An EMG parameter, muscle co-contraction index, was also applied to investigate the session-by-session variation in muscular coordination patterns during the training. The improvement in FMA (shoulder/elbow, wrist/hand) obtained in the NMES robot group was more significant than the robot group (P rehabilitation progress. © The Author(s) 2014.

Surgical therapy by sandwich transplantation using a dermal collagen-elastin matrix and full thickness split grafts and gait rehabilitation with individualized orthesis

Directory of Open Access Journals (Sweden)

Uwe Wollina

2012-01-01

Full Text Available Painful callosities of the feet (PCOF are a rare complaint in children with severe impairment of mobility and quality of life. There is no medical treatment available.We investigated the usefulness of a recently developed combined transplant technique-the sandwich transplantation with dermal collagen-elastin template in this rare condition. A 14-year-old boy suffered from PCOF for several years without any improvement by topical therapy, dermabrasion, and oral retinoids. He was unable to walk normally and suffered from severe pain. We performed a complete deep excision of the hyperkeratotic plantar tissue in general anaesthesia in combination with sandwich transplantation in the same setting. Dry sheets of collagen-elastin matrix (1 mm thickness were placed on the soft tissue defects and covered by full-thickness mesh graft transplants from the upper leg. An individualized orthosis was produced for gait rehabilitation. Two weeks after surgery the gait-related pain was reduced remarkably. Using the orthosis, the boy was able to walk pain-free even on staircase. Surgery of PCOF with sandwich transplantation and gait rehabilitation appears to be a promising strategy for this rare condition.

A robotic exoskeleton to treat crouch gait from cerebral palsy: Initial kinematic and neuromuscular evaluation.

Science.gov (United States)

Lerner, Zachary F; Damiano, Diane L; Bulea, Thomas C

2016-08-01

A robotic exoskeleton was designed for individuals with crouch gait caused by cerebral palsy with the intent to supplement existing muscle function during walking. The aim of this study was to evaluate how powered knee extension assistance provided during stance and swing phases of the gait cycle affect knee kinematics, and knee flexor and extensor muscle activity. Muscle activity and kinematic data were collected from four individuals with crouch gait from cerebral palsy during their normal walking condition and while walking with the exoskeleton under stance, swing, and stance & swing assistance. The exoskeleton was effective in reducing crouch by an average of 13.8° in three of the four participants when assistance was provided during the stance phase; assistance during the swing phase alone was ineffective. Peak knee extensor activity was maintained for all of the conditions during the stance and swing phases. Integrated (i.e. area under the curve) knee extensor activity decreased in two of the subjects indicating a more well-modulated activation pattern. Modest increases in peak and integrated antagonist knee flexor activity were exhibited in all participants; the subject without kinematic improvement had the greatest increase. While the exoskeleton was well tolerated, additional training with a focus on reducing knee flexor activity may lead to further improvements in crouch gait reduction.

How can push-off be preserved during use of an ankle foot orthosis in children with hemiplegia? A prospective controlled study

OpenAIRE

Desloovere, Kaat; Molenaers, Guy; Van Gestel, Leen; Huenaerts, Catherine; Van Campenhout, Anja; Callewaert, Barbara; Van De Walle, Patricia; Seyler, J

2006-01-01

Several studies indicated that walking with an ankle foot orthosis (AFO) impaired third rocker. The purpose of this study was to evaluate the effects of two types of orthoses, with similar goal settings, on gait, in a homogeneous group of children, using both barefoot and shoe walking as control conditions. Fifteen children with hemiplegia, aged between 4 and 10 years, received two types of individually tuned AFOs: common posterior leaf-spring (PLS) and Dual Carbon Fiber Spring AFO (CFO) (wit...

The H2 robotic exoskeleton for gait rehabilitation after stroke: early findings from a clinical study.

Science.gov (United States)

Bortole, Magdo; Venkatakrishnan, Anusha; Zhu, Fangshi; Moreno, Juan C; Francisco, Gerard E; Pons, Jose L; Contreras-Vidal, Jose L

2015-06-17

Stroke significantly affects thousands of individuals annually, leading to considerable physical impairment and functional disability. Gait is one of the most important activities of daily living affected in stroke survivors. Recent technological developments in powered robotics exoskeletons can create powerful adjunctive tools for rehabilitation and potentially accelerate functional recovery. Here, we present the development and evaluation of a novel lower limb robotic exoskeleton, namely H2 (Technaid S.L., Spain), for gait rehabilitation in stroke survivors. H2 has six actuated joints and is designed to allow intensive overground gait training. An assistive gait control algorithm was developed to create a force field along a desired trajectory, only applying torque when patients deviate from the prescribed movement pattern. The device was evaluated in 3 hemiparetic stroke patients across 4 weeks of training per individual (approximately 12 sessions). The study was approved by the Institutional Review Board at the University of Houston. The main objective of this initial pre-clinical study was to evaluate the safety and usability of the exoskeleton. A Likert scale was used to measure patient's perception about the easy of use of the device. Three stroke patients completed the study. The training was well tolerated and no adverse events occurred. Early findings demonstrate that H2 appears to be safe and easy to use in the participants of this study. The overground training environment employed as a means to enhance active patient engagement proved to be challenging and exciting for patients. These results are promising and encourage future rehabilitation training with a larger cohort of patients. The developed exoskeleton enables longitudinal overground training of walking in hemiparetic patients after stroke. The system is robust and safe when applied to assist a stroke patient performing an overground walking task. Such device opens the opportunity to study means

Semi-autonomous exploration of multi-floor buildings with a legged robot

Science.gov (United States)

Wenger, Garrett J.; Johnson, Aaron M.; Taylor, Camillo J.; Koditschek, Daniel E.

2015-05-01

This paper presents preliminary results of a semi-autonomous building exploration behavior using the hexapedal robot RHex. Stairwells are used in virtually all multi-floor buildings, and so in order for a mobile robot to effectively explore, map, clear, monitor, or patrol such buildings it must be able to ascend and descend stairwells. However most conventional mobile robots based on a wheeled platform are unable to traverse stairwells, motivating use of the more mobile legged machine. This semi-autonomous behavior uses a human driver to provide steering input to the robot, as would be the case in, e.g., a tele-operated building exploration mission. The gait selection and transitions between the walking and stair climbing gaits are entirely autonomous. This implementation uses an RGBD camera for stair acquisition, which offers several advantages over a previously documented detector based on a laser range finder, including significantly reduced acquisition time. The sensor package used here also allows for considerable expansion of this behavior. For example, complete automation of the building exploration task driven by a mapping algorithm and higher level planner is presently under development.

Combination of robot-assisted and conventional body-weight-supported treadmill training improves gait in persons with multiple sclerosis: a pilot study.

Science.gov (United States)

Ruiz, Jennifer; Labas, Michele P; Triche, Elizabeth W; Lo, Albert C

2013-12-01

The majority of persons with multiple sclerosis (MS) experience problems with gait, which they characterize as highly disabling impairments that adversely impact their quality of life. Thus, it is crucial to develop effective therapies to improve mobility for these individuals. The purpose of this study was to determine whether combination gait training, using robot-assisted treadmill training followed by conventional body-weight-supported treadmill training within the same session, improved gait and balance in individuals with MS. This study tested combination gait training in 7 persons with MS. The participants were randomized into the immediate therapy group (IT group) or the delayed therapy group (DT group). In phase I of the trial, the IT group received treatment while the DT group served as a concurrent comparison group. In phase II of the trial, the DT group received treatment identical to the treatment received by the IT group in phase I. Outcome measures included the 6-Minute Walk Test (6MWT), the Timed 25-Foot Walk Test, velocity, cadence, and the Functional Reach Test (FRT). Nonparametric statistical techniques were used for analysis. Combination gait training resulted in significantly greater improvements in the 6MWT for the IT group (median change = +59 m) compared with Phase I DT group (median change = -8 m) (P = 0.08) and FRT (median change = +3.3 cm in IT vs -0.8 cm in the DT group phase I; P = 0.03). Significant overall pre-post improvements following combination gait training were found in 6MWT (+32 m; P = 0.02) and FRT (+3.3 cm; P = 0.06) for IT and Phase II DT groups combined. Combination of robot with body-weight-supported treadmill training gait training is feasible and improved 6MWT and FRT distances in persons with MS.Video Abstract available (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A62) for more insights from the authors.

[Robot-aided training in rehabilitation].

Science.gov (United States)

Hachisuka, Kenji

2010-02-01

Recently, new training techniques that involve the use of robots have been used in the rehabilitation of patients with hemiplegia and paraplegia. Robots used for training the arm include the MIT-MANUS, Arm Trainer, mirror-image motion enabler (MIME) robot, and the assisted rehabilitation and measurement (ARM) Guide. Robots that are used for lower-limb training are the Rehabot, Gait Trainer, Lokomat, LOPES Exoskeleton Robot, and Gait Assist Robot. Robot-aided therapy has enabled the functional training of the arm and the lower limbs in an effective, easy, and comfortable manner. Therefore, with this type of therapy, the patients can repeatedly undergo sufficient and accurate training for a prolonged period. However, evidence of the benefits of robot-aided training has not yet been established.

Modeling of Two-Wheeled Self-Balancing Robot Driven by DC Gearmotors

Science.gov (United States)

Frankovský, P.; Dominik, L.; Gmiterko, A.; Virgala, I.; Kurylo, P.; Perminova, O.

2017-08-01

This paper is aimed at modelling a two-wheeled self-balancing robot driven by the geared DC motors. A mathematical model consists of two main parts, the model of robot's mechanical structure and the model of the actuator. Linearized equations of motion are derived and the overall model of the two-wheeled self-balancing robot is represented in state-space realization for the purpose of state feedback controller design.

Light-driven nano-robotics for sub-diffraction probing and sensing

DEFF Research Database (Denmark)

Glückstad, Jesper; Bañas, Andrew Rafael; Palima, Darwin

On the macro-scale robotics typically uses light for carrying information for machine vision for and feedback in artificially intelligent guidance systems and monitoring. Using the miniscule momentum of light shrinking robots down to the micro- and even nano-scale regime creates opportunities......]. Therefore, a generic approach for optimizing lightmatter interaction involves the combination of optimal light-shaping techniques with the use of optimized nano-featured shapes in light-driven micro-robotics structures. In this work, we designed different three-dimensional micro-structures and fabricated...

The effect of frame rate on the ability of experienced gait analysts to identify characteristics of gait from closed circuit television footage.

Science.gov (United States)

Birch, Ivan; Vernon, Wesley; Burrow, Gordon; Walker, Jeremy

2014-03-01

Forensic gait analysis is increasingly being used as part of criminal investigations. A major issue is the quality of the closed circuit television (CCTV) footage used, particularly the frame rate which can vary from 25 frames per second to one frame every 4s. To date, no study has investigated the effect of frame rate on forensic gait analysis. A single subject was fitted with an ankle foot orthosis and recorded walking at 25 frames per second. 3D motion data were also collected, providing an absolute assessment of the gait characteristics. The CCTV footage was then edited to produce a set of eight additional pieces of footage, at various frame rates. Practitioners with knowledge of forensic gait analysis were recruited and instructed to record their observations regarding the characteristics of the subject's gait from the footage. They were sequentially sent web links to the nine pieces of footage, lowest frame rate first, and a simple observation recording form, over a period of 8 months. A sample-based Pearson product-moment correlation analysis of the results demonstrated a significant positive relationship between frame rate and scores (r=0.868, p=0.002). The results of this study show that frame rate affects the ability of experienced practitioners to identify characteristics of gait captured on CCTV footage. Every effort should therefore be made to ensure that CCTV footage likely to be used in criminal proceedings is captured at as high a frame rate as possible. © 2013.

Motor and psychosocial impact of robot-assisted gait training in a real-world rehabilitation setting: A pilot study.

Directory of Open Access Journals (Sweden)

Cira Fundarò

Full Text Available In the last decade robotic devices have been applied in rehabilitation to overcome walking disability in neurologic diseases with promising results. Robot assisted gait training (RAGT using the Lokomat seems not only to improve gait parameters but also the perception of well-being. Data on the psychosocial patient-robot impact are limited, in particular in the real-world of RAGT, in the rehabilitation setting. During rehabilitation training, the Lokomat can be considered an "assistive device for movement". This allowed the use of the Psychosocial Impact of Assistive Device Scale- PIADS to describe patient interaction with the Lokomat. The primary aim of this pilot study was to evaluate the psychosocial impact of the Lokomat in an in-patient rehabilitation setting using the PIADS; secondary aims were to assess whether the psychosocial impact of RAGT is different between pathological sub-groups and if the Lokomat influenced functional variables (Functional Independence Measure scale-FIM and parameters provided by the Lokomat itself. Thirty-nine consecutive patients (69% males, 54.0±18.0 years eligible for Lokomat training, with etiologically heterogeneous walking disabilities (Parkinson's Disease, n = 10; Spinal Cord Injury, n = 21; Ictus Event, n = 8 were enrolled. Patients were assessed with the FIM before and after rehabilitation with Lokomat, and the PIADS was administered after the rehabilitative period with Lokomat. Overall the PIADS score was positive (35.8±21.6, as well as the three sub-scales, pertaining to "ability", "adaptability" and "self-esteem" (17.2±10.4, 8.9±5.5 and 10.1±6.6 respectively with no between-group differences. All patients significantly improved in gait measure and motor FIM scale (difference after-before treatment values: 11.7±9.8 and 11.2±10.3 respectively, increased treadmill speed (0.4 ± 0.2m/s, reduced body weight support (-14.0±9.5% and guidance force (-13.1 ± 10.7%. This pilot study indicates that

Combined effects of cerebellar transcranial direct current stimulation and transcutaneous spinal direct current stimulation on robot-assisted gait training in patients with chronic brain stroke: A pilot, single blind, randomized controlled trial.

Science.gov (United States)

Picelli, Alessandro; Chemello, Elena; Castellazzi, Paola; Filippetti, Mirko; Brugnera, Annalisa; Gandolfi, Marialuisa; Waldner, Andreas; Saltuari, Leopold; Smania, Nicola

2018-01-01

Preliminary evidence showed additional effects of anodal transcranial direct current stimulation over the damaged cerebral hemisphere combined with cathodal transcutaneous spinal direct current stimulation during robot-assisted gait training in chronic stroke patients. This is consistent with the neural organization of locomotion involving cortical and spinal control. The cerebellum is crucial for locomotor control, in particular for avoidance of obstacles, and adaptation to novel conditions during walking. Despite its key role in gait control, to date the effects of transcranial direct current stimulation of the cerebellum have not been investigated on brain stroke patients treated with robot-assisted gait training. To evaluate the effects of cerebellar transcranial direct current stimulation combined with transcutaneous spinal direct current stimulation on robot-assisted gait training in patients with chronic brain stroke. After balanced randomization, 20 chronic stroke patients received ten, 20-minute robot-assisted gait training sessions (five days a week, for two consecutive weeks) combined with central nervous system stimulation. Group 1 underwent on-line cathodal transcranial direct current stimulation over the contralesional cerebellar hemisphere + cathodal transcutaneous spinal direct current stimulation. Group 2 received on-line anodal transcranial direct current stimulation over the damaged cerebral hemisphere + cathodal transcutaneous spinal direct current stimulation. The primary outcome was the 6-minute walk test performed before, after, and at follow-up at 2 and 4 weeks post-treatment. The significant differences in the 6-minute walk test noted between groups at the first post-treatment evaluation (p = 0.041) were not maintained at either the 2-week (P = 0.650) or the 4-week (P = 0.545) follow-up evaluations. Our preliminary findings support the hypothesis that cathodal transcranial direct current stimulation over the contralesional

Examination of a muscular activity estimation model using a Bayesian network for the influence of an ankle foot orthosis.

Science.gov (United States)

Inoue, Jun; Kawamura, Kazuya; Fujie, Masakatsu G

2012-01-01

In the present paper, we examine the appropriateness of a new model to examine the activity of the foot in gait. We developed an estimation model for foot-ankle muscular activity in the design of an ankle-foot orthosis by means of a statistical method. We chose three muscles for measuring muscular activity and built a Bayesian network model to confirm the appropriateness of the estimation model. We experimentally examined the normal gait of a non-disabled subject. We measured the muscular activity of the lower foot muscles using electromyography, the joint angles, and the pressure on each part of the sole. From these data, we obtained the causal relationship at every 10% level for these factors and built models for the stance phase, control term, and propulsive term. Our model has three advantages. First, it can express the influences that change during gait because we use 10% level nodes for each factor. Second, it can express the influences of factors that differ for low and high muscular-activity levels. Third, we created divided models that are able to reflect the actual features of gait. In evaluating the new model, we confirmed it is able to estimate all muscular activity level with an accuracy of over 90%.

EFFECT OF ORTHOTIC SUBTALAR ALIGNMENT WITH CO-ACTIVATION EXERCISE FOR ALTERATION IN GAIT ENDURANCE IN A CHILD WITH CEREBRAL PALSYSINGLE CASE STUDY

Directory of Open Access Journals (Sweden)

K. Vadivelan

2016-10-01

Full Text Available Background: Energy cost of walking is two times higher in children with cerebral palsy when compared with normal children; this may be due to gait abnormalities.There is a negative influence on physical activity and early onsets of fatigue in activities of daily living are evident in cerebral palsy children and the reason for this is increase in energy cost of walking. Therefore, the treatment techniques which targets on correction of gait abnormalities and Energy conservation during walking are important to maintain orimprove independent functioning.The aim is to find out the effects of using Supra Malleolar Orthosis (SMO along with co-activation exercise in the increase of gait endurance and also to encourage independent skills and abilities in cerebral palsy child. Methods: A 14 years child with spastic hemiplegic cerebral palsy was treated with custom made supra malleolar orthotic which was designed with an orthotic support followed with specific exercises, co-activating dorsiflexors and plantar flexors actively and with assistance. The subject was made to do the co-activation exercises 3 days per week for 8 weeks. Step length, stride length, cadence, navicular drop test, medial arch height and calcaneal eversion were measured before starting the treatment and at the end of 8th week. Results: the results of treatment shows that there is an improvement in 2 minutes’ walk test from 7(pre-test to 13, step length from 22 (pre-test to 32,stride length from 36(pre-test to 47,cadence from 39 (pretest to 37 after the use of Supra Malleolar Orthosis (SMO and a co-activation exercises intervention. There was a clear and significant improvement noted in navicular drop test, medial arch height and calcaneal eversion after a period of 8 weeks use of orthosis and exercise intervention when compared with pre-test value. Conclusion: Orthotic subtalar alignment with co-acticvation exercises for alteration in gait endurance in a child is showing

A novel approach to gait synchronization and transition for reconfigurable walking platforms

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Shunsuke Nansai

2015-04-01

Full Text Available Legged robots based on one degree-of-freedom reconfigurable planar leg mechanisms, that are capable of generating multiple useful gaits, are highly desired due to the possibility of handling environments and tasks of high complexity while maintaining simple control schemes. An essential consideration in these reconfigurable legged robots is to attain stability in motion, at rest as well as while transforming from one configuration to another with the minimum number of legs as long as the full range of their walking patterns, resulting from the different gait cycles of their legs, is achieved. To this end, in this paper, we present a method for the generation of input joint trajectories to properly synchronize the movement of quadruped robots with reconfigurable legs. The approach is exemplified in a four-legged robot with reconfigurable Jansen legs capable of generating up to six useful different gait cycles. The proposed technique is validated through simulated results that show the platform׳s stability across its six feasible walking patterns and during gait transition phases, thus considerably extending the capabilities of the non-reconfigurable design.

MIT-Skywalker: A Novel Gait Neurorehabilitation Robot for Stroke and Cerebral Palsy.

Science.gov (United States)

Susko, Tyler; Swaminathan, Krithika; Krebs, Hermano Igo

2016-10-01

The MIT-Skywalker is a novel robotic device developed for the rehabilitation or habilitation of gait and balance after a neurological injury. It represents an embodiment of the concept exhibited by passive walkers for rehabilitation training. Its novelty extends beyond the passive walker quintessence to the unparalleled versatility among lower extremity devices. For example, it affords the potential to implement a novel training approach built upon our working model of movement primitives based on submovements, oscillations, and mechanical impedances. This translates into three distinct training modes: discrete, rhythmic, and balance. The system offers freedom of motion that forces self-directed movement for each of the three modes. This paper will present the technical details of the robotic system as well as a feasibility study done with one adult with stroke and two adults with cerebral palsy. Results of the one-month feasibility study demonstrated that the device is safe and suggested the potential advantages of the three modular training modes that can be added or subtracted to tailor therapy to a particular patient's need. Each participant demonstrated improvement in common clinical and kinematic measurements that must be confirmed in larger randomized control clinical trials.

Development of anthropomorphic robotic hand driven by Pneumatic Artificial Muscles for robotic applications

Science.gov (United States)

Farag, Mohannad; Zainul Azlan, Norsinnira; Hayyan Alsibai, Mohammed

2018-04-01

This paper presents the design and fabrication of a three-fingered anthropomorphic robotic hand. The fingers are driven by tendons and actuated by human muscle-like actuators known as Pneumatic Artificial Muscle (PAM). The proposed design allows the actuators to be mounted outside the hand where each finger can be driven by one PAM actuator and six indirectly interlinked tendons. With this design, the three-fingered hand has a compact size and a lightweight with a mass of 150.25 grams imitating the human being hand in terms of size and weight. The hand also successfully grasped objects with different shapes and weights up to 500 g. Even though the number of PAM actuators equals the number of Degrees of Freedom (DOF), the design guarantees driving of three joints by only one actuator reducing the number of required actuators from 3 to 1. Therefore, this hand is suitable for researches of robotic applications in terms of design, cost and ability to be equipped with several types of sensors.

The Effects on Kinematics and Muscle Activity of Walking in a Robotic Gait Trainer During Zero-Force Control.

Science.gov (United States)

van Asseldonk, Edwin H F; Veneman, Jan F; Ekkelenkamp, Ralf; Buurke, Jaap H; van der Helm, Frans C T; van der Kooij, Herman

2008-08-01

"Assist as needed" control algorithms promote activity of patients during robotic gait training. Implementing these requires a free walking mode of a device, as unassisted motions should not be hindered. The goal of this study was to assess the normality of walking in the free walking mode of the LOPES gait trainer, an 8 degrees-of-freedom lightweight impedance controlled exoskeleton. Kinematics, gait parameters and muscle activity of walking in a free walking mode in the device were compared with those of walking freely on a treadmill. Average values and variability of the spatio-temporal gait variables showed no or small (relative to cycle-to-cycle variability) changes and the kinematics showed a significant and relevant decrease in knee angle range only. Muscles involved in push off showed a small decrease, whereas muscles involved in acceleration and deceleration of the swing leg showed an increase of their activity. Timing of the activity was mainly unaffected. Most of the observed differences could be ascribed to the inertia of the exoskeleton. Overall, walking with the LOPES resembled free walking, although this required several adaptations in muscle activity. These adaptations are such that we expect that Assist as Needed training can be implemented in LOPES.

Modelling and Control of the Multi-Stage Cable Pulley-Driven Flexible-Joint Robot

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Phongsaen Pitakwatchara

2014-07-01

Full Text Available This work is concerned with the task space impedance control of a robot driven through a multi-stage nonlinear flexible transmission system. Specifically, a two degrees-of-freedom cable pulley-driven flexible-joint robot is considered. Realistic modelling of the system is developed within the bond graph modelling framework. The model captures the nonlinear compliance behaviour of the multi-stage cable pulley transmission system, the spring effect of the augmented counterbalancing mechanism, the major loss throughout the system elements, and the typical inertial dynamics of the robot. Next, a task space impedance controller based on limited information about the angle and the current of the motors is designed. The motor current is used to infer the transmitted torque, by which the motor inertia may be modulated. The motor angle is employed to estimate the stationary distal robot link angle and the robot joint velocity. They are used in the controller to generate the desired damping force and to shape the potential energy of the flexible joint robot system to the desired configuration. Simulation and experimental results of the controlled system signify the competency of the proposed control law.

Light-driven micro-robotics with holographic 3D tracking

DEFF Research Database (Denmark)

Glückstad, Jesper

2016-01-01

We recently pioneered the concept of ligh-driven micro-robotics including the new and disruptive 3D-printed micro-tools coined Wave-guided Optical Waveguides that can be real-time optically trapped and “remote-controlled” in a volume with six-degrees-of-freedom. To be exploring the full potential...... of this new drone-like 3D light robotics approach in challenging microscopic geometries requires a versatile and real-time reconfigurable light coupling that can dynamically track a plurality of “light robots” in 3D to ensure continuous optimal light coupling on the fly. Our latest developments in this new...

A Powered Lower Limb Orthosis for Providing Legged Mobility in Paraplegic Individuals.

Science.gov (United States)

Quintero, Hugo A; Farris, Ryan J; Hartigan, Clare; Clesson, Ismari; Goldfarb, Michael

2011-01-01

This paper presents preliminary results on the development of a powered lower limb orthosis intended to provide legged mobility (with the use of a stability aid, such as forearm crutches) to paraplegic individuals. The orthosis contains electric motors at both hip and both knee joints, which in conjunction with ankle-foot orthoses, provides appropriate joint kinematics for legged locomotion. The paper describes the orthosis and the nature of the controller that enables the SCI patient to command the device, and presents data from preliminary trials that indicate the efficacy of the orthosis and controller in providing legged mobility.

The effect of impedance-controlled robotic gait training on walking ability and quality in individuals with chronic incomplete spinal cord injury : An explorative study

NARCIS (Netherlands)

Fleerkotte, B.M.; Koopman, B.; Buurke, J.H.; Van Asseldonk, E.H.F.; Van der Kooij, H.; Rietman, J.S.

2014-01-01

Background There is increasing interest in the use of robotic gait-training devices in walking rehabilitation of incomplete spinal cord injured (iSCI) individuals. These devices provide promising opportunities to increase the intensity of training and reduce physical demands on therapists. Despite

The effect of impedance-controlled robotic gait training on walking ability and quality in individuals with chronic incomplete spinal cord injury: An explorative study

NARCIS (Netherlands)

Fleerkotte, B.M.; Koopman, Bram; Buurke, Jaap; van Asseldonk, Edwin H.F.; van der Kooij, Herman; Rietman, Johan Swanik

2014-01-01

Background There is increasing interest in the use of robotic gait-training devices in walking rehabilitation of incomplete spinal cord injured (iSCI) individuals. These devices provide promising opportunities to increase the intensity of training and reduce physical demands on therapists. Despite

The effects of a new designed forearm orthosis in treatment of lateral epicondylitis.

Science.gov (United States)

Forogh, Bijan; Khalighi, Mohsen; Javanshir, Mohammad Ali; Ghoseiri, Kamiar; Kamali, Mohammad; Raissi, Gholamreza

2012-07-01

This paper reports on the design and testing of a new designed forearm orthosis and explores its efficacious in comparison to the standard counterforce orthosis in patients with lateral epicondylitis. Twenty-four patients were enrolled in this assessor-blinded clinical trial and randomly assigned to two parallel treatment groups. The measures of pain and function, the pain threshold and grip strength were compared using patient rated tennis elbow evaluation (PRTEE) form, algometer and dynamometer respectively at baseline and 4 weeks after treatment. Paired and independent t-test statistical methods recruited for within and between groups comparisons respectively. The both orthoses, counterforce and new-designed, significantly relieved pain, and improved function, pain threshold and grip strength of all patients after 4 weeks application. The new-designed orthosis seemed to be more effective than the counterforce orthosis in pain relief, but there was not any significant difference in efficacious of two types of orthoses regarding function. The new-designed orthosis can significantly relieve pain, improve function, increase pain threshold and grip strength after application. This orthosis seemed to be more effective than counterforce orthosis in relieving pain and increasing the pain threshold probably due to the limitation of forearm supination.

Evaluation of the effectiveness of robotic gait training and gait-focused physical therapy programs for children and youth with cerebral palsy: a mixed methods RCT.

Science.gov (United States)

Wiart, Lesley; Rosychuk, Rhonda J; Wright, F Virginia

2016-06-02

Robot assisted gait training (RAGT) is considered to be a promising approach for improving gait-related gross motor function of children and youth with cerebral palsy. However, RAGT has yet to be empirically demonstrated to be effective. This knowledge gap is particularly salient given the strong interest in this intensive therapy, the high cost of the technology, and the requirement for specialized rehabilitation centre resources. This is a research protocol describing a prospective, multi-centre, concurrent mixed methods study comprised of a randomized controlled trial (RCT) and an interpretive descriptive qualitative design. It is a mixed methods study designed to determine the relative effectiveness of three physical therapy treatment conditions (i.e., RAGT, a functional physical therapy program conducted over-ground (fPT), and RAGT + fPT) on gait related motor skills of ambulatory children with cerebral palsy. Children with cerebral palsy aged 5-18 years who are ambulatory (Gross Motor Function Classification System Levels II and III) will be randomly allocated to one of four treatment conditions: 1) RAGT, 2) fPT, 3) RAGT and fPT combined, or 4) a maintenance therapy only control group. The qualitative component will explicate child and parent experiences with the interventions, provide insight into the values that underlie their therapy goals, and assist with interpretation of the results of the RCT. n/a. NCT02391324 Registered March 12, 2015.

A small biomimetic quadruped robot driven by multistacked dielectric elastomer actuators

Science.gov (United States)

Nguyen, Canh Toan; Phung, Hoa; Dat Nguyen, Tien; Lee, Choonghan; Kim, Uikyum; Lee, Donghyouk; Moon, Hyungpil; Koo, Jachoon; Nam, Jae-do; Ryeol Choi, Hyouk

2014-06-01

A kind of dielectric elastomer (DE) material, called ‘synthetic elastomer’, has been developed based on acrylonitrile butadiene rubber (NBR) to be used as a dielectric elastomer actuator (DEA). By stacking single layers of synthetic elastomer, a linear actuator, called a multistacked actuator, is produced, and used by mechatronic and robotic systems to generate linear motion. In this paper, we demonstrate the application of the multistacked dielectric elastomer actuator in a biomimetic legged robot. A miniature robot driven by a biomimetic actuation system with four 2-DOF (two-degree-of-freedom) legged mechanisms is realized. Based on the experimental results, we evaluate the performance of the proposed robot and validate the feasibility of the multistacked actuator in a locomotion system as a replacement for conventional actuators.

A small biomimetic quadruped robot driven by multistacked dielectric elastomer actuators

International Nuclear Information System (INIS)

Nguyen, Canh Toan; Phung, Hoa; Nguyen, Tien Dat; Lee, Choonghan; Kim, Uikyum; Lee, Donghyouk; Moon, Hyungpil; Koo, Jachoon; Choi, Hyouk Ryeol; Nam, Jae-do

2014-01-01

A kind of dielectric elastomer (DE) material, called ‘synthetic elastomer’, has been developed based on acrylonitrile butadiene rubber (NBR) to be used as a dielectric elastomer actuator (DEA). By stacking single layers of synthetic elastomer, a linear actuator, called a multistacked actuator, is produced, and used by mechatronic and robotic systems to generate linear motion. In this paper, we demonstrate the application of the multistacked dielectric elastomer actuator in a biomimetic legged robot. A miniature robot driven by a biomimetic actuation system with four 2-DOF (two-degree-of-freedom) legged mechanisms is realized. Based on the experimental results, we evaluate the performance of the proposed robot and validate the feasibility of the multistacked actuator in a locomotion system as a replacement for conventional actuators. (paper)

Design on the Control System of a Gait Rehabilitation Training Robot Based on Brain-Computer Interface and Virtual Reality Technology

Directory of Open Access Journals (Sweden)

Hui Wang

2012-10-01

Full Text Available In this paper a control system of a gait rehabilitation training robot based on Brain-Computer Interface (BCI and virtual reality technology is proposed, which makes the patients' rehabilitation training process more interesting. A technique for measuring the mental states of the human and associated applications based on normal brain signals are examined and evaluated firstly. Secondly, the virtual game starts with the information from the BCI and then it runs in the form of a thread, with the singleton design pattern as the main mode. Thirdly, through the synergistic cooperation with the main software, the virtual game can achieve quick and effective access to blood oxygen, heart rate and other physiological information of the patients. At the same time, by means of the hardware control system, the start-up of the gait rehabilitation training robot could be controlled accurately and effectively. Therefore, the plantar pressure information and the velocity information, together with the physiological information of the patients, would be properly reflected in the game lastly and the physical condition of the patients participating in rehabilitation training would also be reflected to a great extent.

3D finite element model of the diabetic neuropathic foot: a gait analysis driven approach.

Science.gov (United States)

Guiotto, Annamaria; Sawacha, Zimi; Guarneri, Gabriella; Avogaro, Angelo; Cobelli, Claudio

2014-09-22

Diabetic foot is an invalidating complication of diabetes that can lead to foot ulcers. Three-dimensional (3D) finite element analysis (FEA) allows characterizing the loads developed in the different anatomical structures of the foot in dynamic conditions. The aim of this study was to develop a subject specific 3D foot FE model (FEM) of a diabetic neuropathic (DNS) and a healthy (HS) subject, whose subject specificity can be found in term of foot geometry and boundary conditions. Kinematics, kinetics and plantar pressure (PP) data were extracted from the gait analysis trials of the two subjects with this purpose. The FEM were developed segmenting bones, cartilage and skin from MRI and drawing a horizontal plate as ground support. Materials properties were adopted from previous literature. FE simulations were run with the kinematics and kinetics data of four different phases of the stance phase of gait (heel strike, loading response, midstance and push off). FEMs were then driven by group gait data of 10 neuropathic and 10 healthy subjects. Model validation focused on agreement between FEM-simulated and experimental PP. The peak values and the total distribution of the pressures were compared for this purpose. Results showed that the models were less robust when driven from group data and underestimated the PP in each foot subarea. In particular in the case of the neuropathic subject's model the mean errors between experimental and simulated data were around the 20% of the peak values. This knowledge is crucial in understanding the aetiology of diabetic foot. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mesh three-dimensional arm orthosis with built-in ultrasound physiotherapy system

Science.gov (United States)

Kashapova, R. M.; Kashapov, R. N.; Kashapova, R. S.

2017-09-01

The possibility of using the built-in ultrasound physiotherapy system of the hand orthosis is explored in the work. The individual mesh orthosis from nylon 12 was manufactured by the 3D prototyping method on the installation of selective laser sintering SLS SPro 60HD. The applied technology of three-dimensional scanning made it possible to obtain a model of the patient’s hand and on the basis of it to build a virtual model of the mesh frame. In the course of the research, the developed system of ultrasound exposure was installed on the orthosis and its tests were carried out. As a result, the acceleration of the healing process and the reduction in the time of wearing orthosis were found.

Estimating the Mechanical Behavior of the Knee Joint during Crouch Gait: Implications for Real-Time Motor Control of Robotic Knee Orthoses

Science.gov (United States)

Damiano, Diane L.; Bulea, Thomas C.

2016-01-01

Individuals with cerebral palsy frequently exhibit crouch gait, a pathological walking pattern characterized by excessive knee flexion. Knowledge of the knee joint moment during crouch gait is necessary for the design and control of assistive devices used for treatment. Our goal was to 1) develop statistical models to estimate knee joint moment extrema and dynamic stiffness during crouch gait, and 2) use the models to estimate the instantaneous joint moment during weight-acceptance. We retrospectively computed knee moments from 10 children with crouch gait and used stepwise linear regression to develop statistical models describing the knee moment features. The models explained at least 90% of the response value variability: peak moment in early (99%) and late (90%) stance, and dynamic stiffness of weight-acceptance flexion (94%) and extension (98%). We estimated knee extensor moment profiles from the predicted dynamic stiffness and instantaneous knee angle. This approach captured the timing and shape of the computed moment (root-mean-squared error: 2.64 Nm); including the predicted early-stance peak moment as a correction factor improved model performance (root-mean-squared error: 1.37 Nm). Our strategy provides a practical, accurate method to estimate the knee moment during crouch gait, and could be used for real-time, adaptive control of robotic orthoses. PMID:27101612

Modeling of Two-Wheeled Self-Balancing Robot Driven by DC Gearmotors

Directory of Open Access Journals (Sweden)

Frankovský P.

2017-08-01

Full Text Available This paper is aimed at modelling a two-wheeled self-balancing robot driven by the geared DC motors. A mathematical model consists of two main parts, the model of robot’s mechanical structure and the model of the actuator. Linearized equations of motion are derived and the overall model of the two-wheeled self-balancing robot is represented in state-space realization for the purpose of state feedback controller design.

Development of quadruped walking locomotion gait generator using a hybrid method

International Nuclear Information System (INIS)

Jasni, F; Shafie, A A

2013-01-01

The earth, in many areas is hardly reachable by the wheeled or tracked locomotion system. Thus, walking locomotion system is becoming a favourite option for mobile robot these days. This is because of the ability of walking locomotion to move on the rugged and unlevel terrains. However, to develop a walking locomotion gait for a robot is not a simple task. Central Pattern Generator (CPGs) method is a biological inspired method that is introduced as a method to develop the gait for the walking robot recently to tackle the issue faced by the conventional method of pre-designed trajectory based method. However, research shows that even the CPG method do have some limitations. Thus, in this paper, a hybrid method that combines CPG and the pre-designed trajectory based method is introduced to develop a walking gait for quadruped walking robot. The 3-D foot trajectories and the joint angle trajectories developed using the proposed method are compared with the data obtained via the conventional method of pre-designed trajectory to confirm the performance

Magnetically-driven medical robots: An analytical magnetic model for endoscopic capsules design

Science.gov (United States)

Li, Jing; Barjuei, Erfan Shojaei; Ciuti, Gastone; Hao, Yang; Zhang, Peisen; Menciassi, Arianna; Huang, Qiang; Dario, Paolo

2018-04-01

Magnetic-based approaches are highly promising to provide innovative solutions for the design of medical devices for diagnostic and therapeutic procedures, such as in the endoluminal districts. Due to the intrinsic magnetic properties (no current needed) and the high strength-to-size ratio compared with electromagnetic solutions, permanent magnets are usually embedded in medical devices. In this paper, a set of analytical formulas have been derived to model the magnetic forces and torques which are exerted by an arbitrary external magnetic field on a permanent magnetic source embedded in a medical robot. In particular, the authors modelled cylindrical permanent magnets as general solution often used and embedded in magnetically-driven medical devices. The analytical model can be applied to axially and diametrically magnetized, solid and annular cylindrical permanent magnets in the absence of the severe calculation complexity. Using a cylindrical permanent magnet as a selected solution, the model has been applied to a robotic endoscopic capsule as a pilot study in the design of magnetically-driven robots.

Human-robot interaction strategies for walker-assisted locomotion

CERN Document Server

Cifuentes, Carlos A

2016-01-01

This book presents the development of a new multimodal human-robot interface for testing and validating control strategies applied to robotic walkers for assisting human mobility and gait rehabilitation. The aim is to achieve a closer interaction between the robotic device and the individual, empowering the rehabilitation potential of such devices in clinical applications. A new multimodal human-robot interface for testing and validating control strategies applied to robotic walkers for assisting human mobility and gait rehabilitation is presented. Trends and opportunities for future advances in the field of assistive locomotion via the development of hybrid solutions based on the combination of smart walkers and biomechatronic exoskeletons are also discussed. .

The Effect of Rocker Bar Ankle Foot Orthosis on Functional Mobility in Post-Stroke Hemiplegic Patients

Directory of Open Access Journals (Sweden)

Farzad Farmani

2015-09-01

Full Text Available Objectives: Ankle Foot Orthoses (AFOs are widely utilized to improve walking ability in hemiplegic patients. The present study aimed to evaluate the effect of Rocker bar Ankle Foot Orthosis (RAFO on functional mobility in post-stroke hemiplegic patients. Methods: Fifteen hemiplegic patients (men and women who were at least 6-months post-stroke and able to walk without assistive device for at least 10 meters voluntarily participated in this study. The patients were examined with and without RAFO. Their functional mobility was evaluated through 10-meter walk test and Timed Up and Go (TUG test. Also, paired t-test was used to analyze obtained data. Results: When patients used RAFO, their gait speed significantly increased (P<0.05. Also, the time of performing TUG test experienced a significant decrease using RAFO compared with utilizing shoe only (P<0.05. Discussion: RAFO led to a significant improvement in functional mobility in hemiplegic patient’s secondary to stroke. It seems that, it has been due to the positive effect of rocker modification on improving push off and transferring weight during stance phase of gait.

Development of Ankle Foot Orthosis (AFO Using Pneumatic Artificial Muscle for Disabled Children

Directory of Open Access Journals (Sweden)

Ishak N.Z.

2017-01-01

Full Text Available Ankle foot orthosis (AFO are commonly used to correct the instabilities and joint weakness of lower limb. In this research, AFO was developed by using pneumatic artificial muscle (PAM to prevent plantarflexion to occur and also to correct the foot from the inversion syndrome. The research started with designing the AFO by using SolidWorks software based on anthropometry measurement data (n=5, age=12 years old. The mechanical simulation was conducted by using Autodesk Inventor software to obtain a safety factor before the fabrication process was conducted. The AFO was fabricated using 3D printer and the thermoplastic elastomer (TPE rubber was selected as the material. PAM was tested by using test bed machine to generate the force and contraction by muscle. The result shows that the PAM was suitable for low speed as the displacement was greater. The AFO could be valuable for the gait rehabilitation.

An Open-Structure Treadmill Gait Trainer: From Research to Application

OpenAIRE

Li, Jian; Chen, Diansheng; Fan, Yubo

2017-01-01

Lower limb rehabilitation robots are designed to enhance gait function in individuals with motor impairments. Although numerous rehabilitation robots have been developed, only few of these robots have been used in practical health care, particularly in China. The objective of this study is to construct a lower limb rehabilitation robot and bridge the gap between research and application. Open structure to facilitate practical application was created for the whole robot. Three typical movement...

Flowrate behavior and clustering of self-driven robots in a channel

Science.gov (United States)

Tian, Bo; Sun, Wang-Ping; Li, Ming; Jiang, Rui; Hu, Mao-Bin

2018-03-01

In this paper, the collective motion of self-driven robots is studied experimentally and theoretically. In the channel, the flowrate of robots increases with the density linearly, even if the density of the robots tends to 1.0. There is no abrupt drop in the flowrate, similar to the collective motion of ants. We find that the robots will adjust their velocities by a serial of tiny collisions. The speed-adjustment will affect both robots involved in the collision, and will help to maintain a nearly uniform velocity for the robots. As a result, the flowrate drop will disappear. In the motion, the robots neither gather together nor scatter completely. Instead, they form some clusters to move together. These clusters are not stable during the moving process, but their sizes follow a power-law-alike distribution. We propose a theoretical model to simulate this collective motion process, which can reproduce these behaviors well. Analytic results about the flowrate behavior are also consistent with experiments. Project supported by the Key Research and Development Program, China (Grant No. 2016YFC0802508) and the National Natural Science Foundation of China (Grant Nos. 11672289 and 11422221).

Defining the mechanical properties of a spring-hinged ankle foot orthosis to assess its potential use in children with spastic cerebral palsy.

Science.gov (United States)

Kerkum, Yvette L; Brehm, Merel-Anne; Buizer, Annemieke I; van den Noort, Josien C; Becher, Jules G; Harlaar, Jaap

2014-12-01

A rigid ventral shelf ankle foot orthosis (AFO) may improve gait in children with spastic cerebral palsy (SCP) whose gait is characterized by excessive knee flexion in stance. However, these AFOs can also impede ankle range of motion (ROM) and thereby inhibit push-off power. A more spring-like AFO can enhance push-off and may potentially reduce walking energy cost. The recent development of an adjustable spring-hinged AFO now allows adjustment of AFO stiffness, enabling tuning toward optimal gait performance. This study aims to quantify the mechanical properties of this spring-hinged AFO for each of its springs and settings. Using an AFO stiffness tester, two AFO hinges and their accompanying springs were measured. The springs showed a stiffness range of 0.01-1.82 N · m · deg(-1). The moment-threshold increased with increasing stiffness (1.13-12.1 N · m), while ROM decreased (4.91-16.5°). Energy was returned by all springs (11.5-116.3 J). These results suggest that the two stiffest available springs should improve joint kinematics and enhance push-off in children with SCP walking with excessive knee flexion.

A Powered Lower Limb Orthosis for Providing Legged Mobility in Paraplegic Individuals

OpenAIRE

Quintero, Hugo A.; Farris, Ryan J.; Hartigan, Clare; Clesson, Ismari; Goldfarb, Michael

2011-01-01

This paper presents preliminary results on the development of a powered lower limb orthosis intended to provide legged mobility (with the use of a stability aid, such as forearm crutches) to paraplegic individuals. The orthosis contains electric motors at both hip and both knee joints, which in conjunction with ankle-foot orthoses, provides appropriate joint kinematics for legged locomotion. The paper describes the orthosis and the nature of the controller that enables the SCI patient to comm...

Simulations and experimental evaluation of an active orthosis for interaction in virtual environments

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Tsveov Mihail

2018-01-01

Full Text Available In this work, the development of a human arm active orthosis is presented. The orthosis is designed primarily for training and rehabilitation in virtual environments.The orthosis system is intended for embodiment in virtual reality where it is allowing human to perceive forces at different body parts or the weight of lifted objects. In the paper the choice of a mechanical structure is shown equivalent to the structure of the human arm. A mechanical model of the orthosis arm as haptic device is built, where kinematic and dynamic parameters are evaluated. Impedance control scheme is selected as the most suitable for force refection at the hand or arm. An open-loop impedance controller is presented in the paper. Computer experiments are carried out using the dimensions of a real arm orthosis. Computer experiments have been carried out to provide force reflection by VR, according to virtual scenario. The conducted simulations show the range of the forces on the operator hand, orthosis can provide. The results of additional measurements and experimental evaluations of physical quantities in the interaction in a virtual environment are revealed in the paper.

Sensor-driven, fault-tolerant control of a maintenance robot

International Nuclear Information System (INIS)

Moy, M.M.; Davidson, W.M.

1987-01-01

A robot system has been designed to do routine maintenance tasks on the Sandia Pulsed Reactor (SPR). The use of this Remote Maintenance Robot (RMR) is expected to significantly reduce the occupational radiation exposure of the reactor operators. Reactor safety was a key issue in the design of the robot maintenance system. Using sensors to detect error conditions and intelligent control to recover from the errors, the RMR is capable of responding to error conditions without creating a hazard. This paper describes the design and implementation of a sensor-driven, fault-tolerant control for the RMR. Recovery from errors is not automatic; it does rely on operator assistance. However, a key feature of the error recovery procedure is that the operator is allowed to reenter the programmed operation after the error has been corrected. The recovery procedure guarantees that the moving components of the system will not collide with the reactor during recovery

Effect of ankle-foot orthosis on postural control after stroke: a systematic review.

Science.gov (United States)

Guerra Padilla, M; Molina Rueda, F; Alguacil Diego, I M

2014-09-01

Stroke is currently the main cause of permanent disability in adults. The impairments are a combination of sensory, motor, cognitive and emotional changes that result in restrictions on the ability to perform basic activities of daily living (BADL). Postural control is affected and causes problems with static and dynamic balance, thus increasing the risk of falls and secondary injuries. The purpose of this review was to compile the literature to date, and assess the impact of ankle-foot orthosis (AFO) on postural control and gait in individuals who have suffered a stroke. The review included randomised and controlled trials that examined the effects of AFO in stroke patients between 18 and 80 years old, with acute or chronic evolution. No search limits on the date of the studies were included, and the search lasted until April 2011. The following databases were used: Pubmed, Trip Database, Cochrane library, Embase, ISI Web Knowledge, CINHAL and PEDro. Intervention succeeded in improving some gait parameters, such as speed and cadence. However it is not clear if there was improvement in the symmetry, postural sway or balance. Because of the limitations of this systematic review, due to the clinical diversity of the studies and the methodological limitations, 0these results should be considered with caution. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

Perception-Driven Obstacle-Aided Locomotion for Snake Robots: The State of the Art, Challenges and Possibilities †

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Filippo Sanfilippo

2017-03-01

Full Text Available In nature, snakes can gracefully traverse a wide range of different and complex environments. Snake robots that can mimic this behaviour could be fitted with sensors and transport tools to hazardous or confined areas that other robots and humans are unable to access. In order to carry out such tasks, snake robots must have a high degree of awareness of their surroundings (i.e., perception-driven locomotion and be capable of efficient obstacle exploitation (i.e., obstacle-aided locomotion to gain propulsion. These aspects are pivotal in order to realise the large variety of possible snake robot applications in real-life operations such as fire-fighting, industrial inspection, search-and-rescue, and more. In this paper, we survey and discuss the state of the art, challenges, and possibilities of perception-driven obstacle-aided locomotion for snake robots. To this end, different levels of autonomy are identified for snake robots and categorised into environmental complexity, mission complexity, and external system independence. From this perspective, we present a step-wise approach on how to increment snake robot abilities within guidance, navigation, and control in order to target the different levels of autonomy. Pertinent to snake robots, we focus on current strategies for snake robot locomotion in the presence of obstacles. Moreover, we put obstacle-aided locomotion into the context of perception and mapping. Finally, we present an overview of relevant key technologies and methods within environment perception, mapping, and representation that constitute important aspects of perception-driven obstacle-aided locomotion.

Modelling of the Human Knee Joint Supported by Active Orthosis

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Musalimov, V.; Monahov, Y.; Tamre, M.; Rõbak, D.; Sivitski, A.; Aryassov, G.; Penkov, I.

2018-02-01

The article discusses motion of a healthy knee joint in the sagittal plane and motion of an injured knee joint supported by an active orthosis. A kinematic scheme of a mechanism for the simulation of a knee joint motion is developed and motion of healthy and injured knee joints are modelled in Matlab. Angles between links, which simulate the femur and tibia are controlled by Simulink block of Model predictive control (MPC). The results of simulation have been compared with several samples of real motion of the human knee joint obtained from motion capture systems. On the basis of these analyses and also of the analysis of the forces in human lower limbs created at motion, an active smart orthosis is developed. The orthosis design was optimized to achieve an energy saving system with sufficient anatomy, necessary reliability, easy exploitation and low cost. With the orthosis it is possible to unload the knee joint, and also partially or fully compensate muscle forces required for the bending of the lower limb.

Modelling of the Human Knee Joint Supported by Active Orthosis

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Musalimov V.

2018-02-01

Full Text Available The article discusses motion of a healthy knee joint in the sagittal plane and motion of an injured knee joint supported by an active orthosis. A kinematic scheme of a mechanism for the simulation of a knee joint motion is developed and motion of healthy and injured knee joints are modelled in Matlab. Angles between links, which simulate the femur and tibia are controlled by Simulink block of Model predictive control (MPC. The results of simulation have been compared with several samples of real motion of the human knee joint obtained from motion capture systems. On the basis of these analyses and also of the analysis of the forces in human lower limbs created at motion, an active smart orthosis is developed. The orthosis design was optimized to achieve an energy saving system with sufficient anatomy, necessary reliability, easy exploitation and low cost. With the orthosis it is possible to unload the knee joint, and also partially or fully compensate muscle forces required for the bending of the lower limb.

A pneumatic power harvesting ankle-foot orthosis to prevent foot-drop

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Chin Robin

2009-06-01

Full Text Available Abstract Background A self-contained, self-controlled, pneumatic power harvesting ankle-foot orthosis (PhAFO to manage foot-drop was developed and tested. Foot-drop is due to a disruption of the motor control pathway and may occur in numerous pathologies such as stroke, spinal cord injury, multiple sclerosis, and cerebral palsy. The objectives for the prototype PhAFO are to provide toe clearance during swing, permit free ankle motion during stance, and harvest the needed power with an underfoot bellow pump pressurized during the stance phase of walking. Methods The PhAFO was constructed from a two-part (tibia and foot carbon composite structure with an articulating ankle joint. Ankle motion control was accomplished through a cam-follower locking mechanism actuated via a pneumatic circuit connected to the bellow pump and embedded in the foam sole. Biomechanical performance of the prototype orthosis was assessed during multiple trials of treadmill walking of an able-bodied control subject (n = 1. Motion capture and pressure measurements were used to investigate the effect of the PhAFO on lower limb joint behavior and the capacity of the bellow pump to repeatedly generate the required pneumatic pressure for toe clearance. Results Toe clearance during swing was successfully achieved during all trials; average clearance 44 ± 5 mm. Free ankle motion was observed during stance and plantarflexion was blocked during swing. In addition, the bellow component repeatedly generated an average of 169 kPa per step of pressure during ten minutes of walking. Conclusion This study demonstrated that fluid power could be harvested with a pneumatic circuit built into an AFO, and used to operate an actuated cam-lock mechanism that controls ankle-foot motion at specific periods of the gait cycle.

Prototyping of Individual Ankle Orthosis Using Additive Manufacturing Technologies

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Natalia Wierzbicka

2017-09-01

Full Text Available The paper presents design and manufacturing process of an individualized ankle orthosis using additive manufacturing technologies and reverse engineering. Conventional processes of manufacturing of orthosesareexpensive and time consuming -an alternative method was proposed. The patient’s leg was 3D scanned and the orthosis was designed using a CAD system. It was then manufactured using the Fused Deposition Modelling technology, assembled and fully tested. Positive results were obtained.

Human-robot interaction tests on a novel robot for gait assistance.

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Tagliamonte, Nevio Luigi; Sergi, Fabrizio; Carpino, Giorgio; Accoto, Dino; Guglielmelli, Eugenio

2013-06-01

This paper presents tests on a treadmill-based non-anthropomorphic wearable robot assisting hip and knee flexion/extension movements using compliant actuation. Validation experiments were performed on the actuators and on the robot, with specific focus on the evaluation of intrinsic backdrivability and of assistance capability. Tests on a young healthy subject were conducted. In the case of robot completely unpowered, maximum backdriving torques were found to be in the order of 10 Nm due to the robot design features (reduced swinging masses; low intrinsic mechanical impedance and high-efficiency reduction gears for the actuators). Assistance tests demonstrated that the robot can deliver torques attracting the subject towards a predicted kinematic status.

A cable-driven soft robot surgical system for cardiothoracic endoscopic surgery: preclinical tests in animals.

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Wang, Hesheng; Zhang, Runxi; Chen, Weidong; Wang, Xiaozhou; Pfeifer, Rolf

2017-08-01

Minimally invasive surgery attracts more and more attention because of the advantages of minimal trauma, less bleeding and pain and low complication rate. However, minimally invasive surgery for beating hearts is still a challenge. Our goal is to develop a soft robot surgical system for single-port minimally invasive surgery on a beating heart. The soft robot described in this paper is inspired by the octopus arm. Although the octopus arm is soft and has more degrees of freedom (DOFs), it can be controlled flexibly. The soft robot is driven by cables that are embedded into the soft robot manipulator and can control the direction of the end and middle of the soft robot manipulator. The forward, backward and rotation movement of the soft robot is driven by a propulsion plant. The soft robot can move freely by properly controlling the cables and the propulsion plant. The soft surgical robot system can perform different thoracic operations by changing surgical instruments. To evaluate the flexibility, controllability and reachability of the designed soft robot surgical system, some testing experiments have been conducted in vivo on a swine. Through the subxiphoid, the soft robot manipulator could enter into the thoracic cavity and pericardial cavity smoothly and perform some operations such as biopsy, ligation and ablation. The operations were performed successfully and did not cause any damage to the surrounding soft tissues. From the experiments, the flexibility, controllability and reachability of the soft robot surgical system have been verified. Also, it has been shown that this system can be used in the thoracic and pericardial cavity for different operations. Compared with other endoscopy robots, the soft robot surgical system is safer, has more DOFs and is more flexible for control. When performing operations in a beating heart, this system maybe more suitable than traditional endoscopy robots.

Scoliosis curve analysis with Milwaukee orthosis based on Open SIMM modeling

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Mohammad Karimi

2015-01-01

Full Text Available Background: Scoliosis is a three-dimensional spinal deformity characterized by lateral curvature and rotational deformity of the spine. Various methods have been used to investigate the performance of the subjects during walking with an orthosis, but nobody study the biomechanics of orthotic use by understanding the length of the muscles and the force produced by them. Therefore, the aim of this research is to test the effect of the orthosis on the muscular force, tendon length during walking with and without orthosis. Materials and Methods: A 12-year-old scoliosis subject was recruited in this study. The forces produced by trunk musculature, joint reaction force, length of trunk musculature were some parameters selected in this study. Open SIMM and Visual 3D software were used to model the subject. Results: The results of this research showed that the length of erector spine muscles increased follow the use of orthosis. Moreover, the force produced by trunk muscles differed during walking with and without orthosis and also between right and left sides. Discussion: It seems that Open SIMM software can be used to predict the length of muscles, active-passive forces produced by muscles in scoliotic subjects. Therefore, it is recommended this research be done on more number of subjects.

Scoliosis curve analysis with Milwaukee orthosis based on Open SIMM modeling.

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Karimi, Mohammad; Kavyani, Mahsa

2015-01-01

Scoliosis is a three-dimensional spinal deformity characterized by lateral curvature and rotational deformity of the spine. Various methods have been used to investigate the performance of the subjects during walking with an orthosis, but nobody study the biomechanics of orthotic use by understanding the length of the muscles and the force produced by them. Therefore, the aim of this research is to test the effect of the orthosis on the muscular force, tendon length during walking with and without orthosis. A 12-year-old scoliosis subject was recruited in this study. The forces produced by trunk musculature, joint reaction force, length of trunk musculature were some parameters selected in this study. Open SIMM and Visual 3D software were used to model the subject. The results of this research showed that the length of erector spine muscles increased follow the use of orthosis. Moreover, the force produced by trunk muscles differed during walking with and without orthosis and also between right and left sides. It seems that Open SIMM software can be used to predict the length of muscles, active-passive forces produced by muscles in scoliotic subjects. Therefore, it is recommended this research be done on more number of subjects.

Skeletal and Clinical Effects of Exoskeletal Assisted - Gait

Science.gov (United States)

2016-10-01

clinical functional outcomes. The hypothesis of the study is that exoskeleton -assisted ambulation has skeletal and general health benefits for...for the use of robotic exoskeletons to enable gait in individuals with a complete SCI, clinical teams are not provided with appropriate tools to...estimate or predict potential health benefits (e.g. bone health) associated with exoskeleton -assisted gait. What was the impact on other disciplines

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients

OpenAIRE

Hesse, Stefan; Waldner, Andreas; Tomelleri, Christopher

2010-01-01

Abstract Background Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation pat...

The smart Peano fluidic muscle: a low profile flexible orthosis actuator that feels pain

Science.gov (United States)

Veale, Allan J.; Anderson, Iain A.; Xie, Shane Q.

2015-03-01

Robotic orthoses have the potential to provide effective rehabilitation while overcoming the availability and cost constraints of therapists. These orthoses must be characterized by the naturally safe, reliable, and controlled motion of a human therapist's muscles. Such characteristics are only possible in the natural kingdom through the pain sensing realized by the interaction of an intelligent nervous system and muscles' embedded sensing organs. McKibben fluidic muscles or pneumatic muscle actuators (PMAs) are a popular orthosis actuator because of their inherent compliance, high force, and muscle-like load-displacement characteristics. However, the circular cross-section of PMA increases their profile. PMA are also notoriously unreliable and difficult to control, lacking the intelligent pain sensing systems of their biological muscle counterparts. Here the Peano fluidic muscle, a new low profile yet high-force soft actuator is introduced. This muscle is smart, featuring bioinspired embedded pressure and soft capacitive strain sensors. Given this pressure and strain feedback, experimental validation shows that a lumped parameter model based on the muscle geometry and material parameters can be used to predict its force for quasistatic motion with an average error of 10 - 15N. Combining this with a force threshold pain sensing algorithm sets a precedent for flexible orthosis actuation that uses embedded sensors to prevent damage to the actuator and its environment.

Bio-inspired step-climbing in a hexapod robot

International Nuclear Information System (INIS)

Chou, Ya-Cheng; Yu, Wei-Shun; Huang, Ke-Jung; Lin, Pei-Chun

2012-01-01

Inspired by the observation that the cockroach changes from a tripod gait to a different gait for climbing high steps, we report on the design and implementation of a novel, fully autonomous step-climbing maneuver, which enables a RHex-style hexapod robot to reliably climb a step up to 230% higher than the length of its leg. Similar to the climbing strategy most used by cockroaches, the proposed maneuver is composed of two stages. The first stage is the ‘rearing stage,’ inclining the body so the front side of the body is raised and it is easier for the front legs to catch the top of the step, followed by the ‘rising stage,’ maneuvering the body's center of mass to the top of the step. Two infrared range sensors are installed on the front of the robot to detect the presence of the step and its orientation relative to the robot's heading, so that the robot can perform automatic gait transition, from walking to step-climbing, as well as correct its initial tilt approaching posture. An inclinometer is utilized to measure body inclination and to compute step height, thus enabling the robot to adjust its gait automatically, in real time, and to climb steps of different heights and depths successfully. The algorithm is applicable for the robot to climb various rectangular obstacles, including a narrow bar, a bar and a step (i.e. a bar of infinite width). The performance of the algorithm is evaluated experimentally, and the comparison of climbing strategies and climbing behaviors in biological and robotic systems is discussed. (paper)

[Effect of abducens orthosis combined with walker on developmental dysplasia of the hip].

Science.gov (United States)

Hu, Zhiyong; Xu, Yongqiang; Liang, Jieyu; Li, Kanghua; Liao, Qiande

2009-07-01

To evaluate the effect of abducens orthosis combined with walker on developmental dysplasia of the hip (DDH). A total of 126 patients (224 hips) with DDH aged 6-36 months in Xiangya Hospital was randomly divided into 2 groups: an orthosis combined with walker group and an improved hip frog cast fixation group. Seventy patients (130 hips) were treated by the orthosis combined with walker and 56 patients (94 hips) were treated by the improved hip frog cast fixation. We compared the effect and complications of the 2 groups. The fineness rates of the orthosis combined with walker group and the improved hip frog cast fixation group were 89.2% and 90.4%, respectively, with no significant difference (P>0.05). The rate of femoral head osteonecrosis in the orthosis combined with walker group was significantly lower than that in the improved hip frog cast fixation group (1.5% vs. 5.3%,Pwalker has a lower proportion of femoral head osteonecrosis, but a higher proportion of re-dislocation.

Effect of New Kypho-Remainder Orthosis on Curve Intensity in Adults With Postural Hyper Kyphosis

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Omid Torkaman

2017-10-01

Conclusion Considering the importance of maintaining a proper posture to optimize the muscles activity in preventing deformity and orthosis with a bio-feedback mechanism may be the solution. The long-term effect of using a bio-feedback orthosis indicated that kypho-remainder orthosis can significantly improve the kyphosis curve in individuals with postural hyper-kyphosis. 

Biomechanical effects of robot assisted walking on knee joint kinematics and muscle activation pattern.

Science.gov (United States)

Thangavel, Pavithra; Vidhya, S; Li, Junhua; Chew, Effie; Bezerianos, Anastasios; Yu, Haoyong

2017-07-01

Since manual rehabilitation therapy can be taxing for both the patient and the physiotherapist, a gait rehabilitation robot has been built to reduce the physical strain and increase the efficacy of the rehabilitation therapy. The prototype of the gait rehabilitation robot is designed to provide assistance while walking for patients with abnormal gait pattern and it can also be used for rehabilitation therapy to restore an individual's normal gait pattern by aiding motor recovery. The Gait Rehabilitation Robot uses gait event based synchronization, which enables the exoskeleton to provide synchronous assistance during walking that aims to reduce the lower-limb muscle activation. This study emphasizes on the biomechanical effects of assisted walking on the lower limb by analyzing the EMG signal, knee joint kinematics data that was collected from the right leg during the various experimental conditions. The analysis of the measured data shows an improved knee joint trajectory and reduction in muscle activity with assistance. The result of this study does not only assess the functionality of the exoskeleton but also provides a profound understanding of the human-robot interaction by studying the effects of assistance on the lower limb.

Clinical feasibility of gait training with a robotic exoskeleton (WPAL) in an individual with both incomplete cervical and complete thoracic spinal cord injury: A case study.

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Tanabe, Shigeo; Koyama, Soichiro; Saitoh, Eiichi; Hirano, Satoshi; Yatsuya, Kanan; Tsunoda, Tetsuya; Katoh, Masaki; Gotoh, Takeshi; Furumoto, Ayako

2017-01-01

Patients with tetraplegia can achieve independent gait with lateral-type powered exoskeletons; it is unclear whether medial-type powered exoskeletons allow for this. To investigate gait training with a medial-type powered exoskeleton wearable power-assist locomotor (WPAL) in an individual with incomplete cervical (C5) and complete thoracic (T12) spinal cord injury (SCI). The 60-session program was investigated retrospectively using medical records. Upon completion, gait performance was examined using three-dimensional motion analyses and surface electromyography (EMG) of the upper limbs. The subject achieved independent gait with WPAL and a walker in 12 sessions. He continuously extended his right elbow; his left elbow periodically flexed/extended. His pelvic inclination was larger than the trunk inclination during single-leg stance. EMG activity was increased in the left deltoid muscles during ipsilateral foot-contact. The right anterior and medial deltoid muscle EMG activity increased just after foot-off for each leg, as did the right biceps activity. Continuous activity was observed in the left triceps throughout the gait cycle; activity was unclear in the right triceps. These results suggest the importance of upper limb residual motor function, and may be useful in extending the range of clinical applications for robotic gait rehabilitation in patients with SCI.

Trajectory Generation and Stability Analysis for Reconfigurable Klann Mechanism Based Walking Robot

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Jaichandar Kulandaidaasan Sheba

2016-06-01

Full Text Available Reconfigurable legged robots based on one degree of freedom are highly desired because they are effective on rough and irregular terrains and they provide mobility in such terrain with simple control schemes. It is necessary that reconfigurable legged robots should maintain stability during rest and motion, with a minimum number of legs while maintaining their full range of walking patterns resulting from different gait configuration. In this paper we present a method to generate input trajectory for reconfigurable quadruped robots based on Klann mechanism to properly synchronize movement. Six useful gait cycles based on this reconfigurable Klann mechanism for quadruped robots has been clearly shown here. The platform stability for these six useful gait cycles are validated through simulated results which clearly shows the capabilities of reconfigurable design.

Nonlinear disturbance observer based sliding mode control of a cable-driven rehabilitation robot.

Science.gov (United States)

Niu, Jie; Yang, Qianqian; Chen, Guangtao; Song, Rong

2017-07-01

This paper introduces a cable-driven robot for upper-limb rehabilitation. Kinematic and dynamic of this rehabilitation robot is analyzed. A sliding mode controller combined with a nonlinear disturbance observer is proposed to control this robot in the presence of disturbances. Simulation is carried out to prove the effectiveness of the proposed control scheme, and the results of the proposed controller is compared with a PID controller and a traditional sliding mode controller. Results show that the proposed controller can effectively improve the tracking performance as compared with the other two controllers and cause lower chattering as compared with a traditional sliding mode controller.

Pneumatic Muscles Actuated Lower-Limb Orthosis Model Verification with Actual Human Muscle Activation Patterns

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Dzahir M.A.M

2017-01-01

Full Text Available A review study was conducted on existing lower-limb orthosis systems for rehabilitation which implemented pneumatic muscle type of actuators with the aim to clarify the current and on-going research in this field. The implementation of pneumatic artificial muscle will play an important role for the development of the advanced robotic system. In this research a derivation model for the antagonistic mono- and bi-articular muscles using pneumatic artificial muscles of a lower limb orthosis will be verified with actual human’s muscle activities models. A healthy and young male 29 years old subject with height 174cm and weight 68kg was used as a test subject. Two mono-articular muscles Vastus Medialis (VM and Vastus Lateralis (VL were selected to verify the mono-articular muscle models and muscle synergy between anterior muscles. Two biarticular muscles Rectus Femoris (RF and Bicep Femoris (BF were selected to verify the bi-articular muscle models and muscle co-contraction between anterior-posterior muscles. The test was carried out on a treadmill with a speed of 4.0 km/h, which approximately around 1.25 m/s for completing one cycle of walking motion. The data was collected for about one minute on a treadmill and 20 complete cycles of walking motion were successfully recorded. For the evaluations, the mathematical model obtained from the derivation and the actual human muscle activation patterns obtained using the surface electromyography (sEMG system were compared and analysed. The results shown that, high correlation values ranging from 0.83 up to 0.93 were obtained in between the derivation model and the actual human muscle’s model for both mono- and biarticular muscles. As a conclusion, based on the verification with the sEMG muscle activities data and its correlation values, the proposed derivation models of the antagonistic mono- and bi-articular muscles were suitable to simulate and controls the pneumatic muscles actuated lower limb

Novel actuation design of a gait trainer with shadow leg approach.

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Meuleman, Jos; Meuleman, Jos; van Asseldonk, Edwin H F; van der Kooij, Herman

2013-06-01

Robotic gait training has developed since the end of the 20(th) century, yet there is much room for improvement in the design of the robots. With the conventional exoskeleton structures, donning of patients in a gait trainer usually is a cumbersome process due to the need of joint alignments and normal walking is often hindered due to obstructed arm swing. Our goal was to design a gait training robots that overcomes these limitations. We propose a novel design in which these drawbacks are reduced to a great amount. By using a parallel structure behind the patient (shadow leg) that is connected to the patient joints with rods, little alignment is needed, the area lateral to the hip is left free, and thus arm swing is not obstructed. The construction is lightweight, because the actuators are mounted on a fixed base and the transmission of power is executed with light weight rods. An end stop in the shadow leg prevents hyper extension of the patient's knee. The relationship between motor displacement and human joint rotations is nonlinear. In this paper we derive the nonlinear relationships between motors and patient joints and verify these. calculations with a measurement. The device has been built, now tests with subjects are required to assess if subjects can indeed walk normally in the robot.

Sliding Mode Tracking Control of a Wire-Driven Upper-Limb Rehabilitation Robot with Nonlinear Disturbance Observer

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Jie Niu

2017-12-01

Full Text Available Robot-aided rehabilitation has become an important technology to restore and reinforce motor functions of patients with extremity impairment, whereas it can be extremely challenging to achieve satisfactory tracking performance due to uncertainties and disturbances during rehabilitation training. In this paper, a wire-driven rehabilitation robot that can work over a three-dimensional space is designed for upper-limb rehabilitation, and sliding mode control with nonlinear disturbance observer is designed for the robot to deal with the problem of unpredictable disturbances during robot-assisted training. Then, simulation and experiments of trajectory tracking are carried out to evaluate the performance of the system, the position errors, and the output forces of the designed control scheme are compared with those of the traditional sliding mode control (SMC scheme. The results show that the designed control scheme can effectively reduce the tracking errors and chattering of the output forces as compared with the traditional SMC scheme, which indicates that the nonlinear disturbance observer can reduce the effect of unpredictable disturbances. The designed control scheme for the wire-driven rehabilitation robot has potential to assist patients with stroke in performing repetitive rehabilitation training.

Robotic Hand-Assisted Training for Spinal Cord Injury Driven by Myoelectric Pattern Recognition: A Case Report.

Science.gov (United States)

Lu, Zhiyuan; Tong, Kai-Yu; Shin, Henry; Stampas, Argyrios; Zhou, Ping

2017-10-01

A 51-year-old man with an incomplete C6 spinal cord injury sustained 26 yrs ago attended twenty 2-hr visits over 10 wks for robot-assisted hand training driven by myoelectric pattern recognition. In each visit, his right hand was assisted to perform motions by an exoskeleton robot, while the robot was triggered by his own motion intentions. The hand robot was designed for this study, which can perform six kinds of motions, including hand closing/opening; thumb, index finger, and middle finger closing/opening; and middle, ring, and little fingers closing/opening. After the training, his grip force increased from 13.5 to 19.6 kg, his pinch force remained the same (5.0 kg), his score of Box and Block test increased from 32 to 39, and his score from the Graded Redefined Assessment of Strength, Sensibility, and Prehension test Part 4.B increased from 22 to 24. He accomplished the tasks in the Graded Redefined Assessment of Strength, Sensibility, and Prehension test Part 4.B 28.8% faster on average. The results demonstrate the feasibility and effectiveness of robot-assisted training driven by myoelectric pattern recognition after spinal cord injury.

Artificial Leg Design and Control Research of a Biped Robot with Heterogeneous Legs Based on PID Control Algorithm

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Hualong Xie

2015-04-01

Full Text Available A biped robot with heterogeneous legs (BRHL is proposed to provide an ideal test-bed for intelligent bionic legs (IBL. To make artificial leg gait better suited to a human, a four-bar mechanism is used as its knee joint, and a pneumatic artificial muscle (PAM is used as its driving source. The static mathematical model of PAM is established and the mechanical model of a single degree of freedom of a knee joint driven by PAM is analyzed. A control simulation of an artificial leg based on PID control algorithm is carried out and the simulation results indicate that the artificial leg can simulate precisely a normal human walking gait.

Effects of electromyography-driven robot-aided hand training with neuromuscular electrical stimulation on hand control performance after chronic stroke.

Science.gov (United States)

Rong, Wei; Tong, Kai Yu; Hu, Xiao Ling; Ho, Sze Kit

2015-03-01

An electromyography-driven robot system integrated with neuromuscular electrical stimulation (NMES) was developed to investigate its effectiveness on post-stroke rehabilitation. The performance of this system in assisting finger flexion/extension with different assistance combinations was evaluated in five stroke subjects. Then, a pilot study with 20-sessions training was conducted to evaluate the training's effectiveness. The results showed that combined assistance from the NMES-robot could improve finger movement accuracy, encourage muscle activation of the finger muscles and suppress excessive muscular activities in the elbow joint. When assistances from both NMES and the robot were 50% of their maximum assistances, finger-tracking performance had the best results, with the lowest root mean square error, greater range of motion, higher voluntary muscle activations of the finger joints and lower muscle co-contraction in the finger and elbow joints. Upper limb function improved after the 20-session training, indicated by the increased clinical scores of Fugl-Meyer Assessment, Action Research Arm Test and Wolf Motor Function Test. Muscle co-contraction was reduced in the finger and elbow joints reflected by the Modified Ashworth Scale. The findings demonstrated that an electromyography-driven NMES-robot used for chronic stroke improved hand function and tracking performance. Further research is warranted to validate the method on a larger scale. Implications for Rehabilitation The hand robotics and neuromuscular electrical stimulation (NMES) techniques are still separate systems in current post-stroke hand rehabilitation. This is the first study to investigate the combined effects of the NMES and robot on hand rehabilitation. The finger tracking performance was improved with the combined assistance from the EMG-driven NMES-robot hand system. The assistance from the robot could improve the finger movement accuracy and the assistance from the NMES could reduce the

Effects of walkbot gait training on kinematics, kinetics, and clinical gait function in paraplegia and quadriplegia.

Science.gov (United States)

Hwang, Jongseok; Shin, Yongil; Park, Ji-Ho; Cha, Young Joo; You, Joshua Sung H

2018-04-07

The robotic-assisted gait training (RAGT) system has gained recognition as an innovative, effective paradigm to improve functional ambulation and activities of daily living in spinal cord injury and stroke. However, the effects of the Walkbot robotic-assisted gait training system with a specialized hip-knee-ankle actuator have never been examined in the paraplegia and quadriplegia population. The aim of this study was to determine the long-term effects of Walkbot training on clinical for hips and knee stiffness in individuals with paraplegia or quadriplegia. Nine adults with subacute or chronic paraplegia resulting from spinal cord injury or quadriplegia resulting from cerebral vascular accident (CVA) and/or hypoxia underwent progressive conventional gait retraining combined with the Walkbot RAGT for 5 days/week over an average of 43 sessions for 8 weeks. Clinical outcomes were measured with the Functional Ambulation Category (FAC), Modified Rankin Scale (MRS), Korean version of the Modified Barthel Index (K-MBI), Modified Ashworth Scale (MAS). Kinetic and kinematic data were collected via a built-in Walkbot program. Wilcoxon signed-rank tests showed significant positive intervention effects on K-MBI, maximal hip flexion and extension, maximal knee flexion, active torque in the knee joint, resistive torque, and stiffness in the hip joint (P quadriplegia who had reached a plateau in motor recovery after conventional therapy.

Counterforce Orthosis In The Management Of Lateral Epicondylitis.

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Vellilappilly, Daison Varghese; Rai, Heroor Ravindranath; Varghese, Jaison; Renjith, Vishnu

2017-01-01

Lateral Epicondylitis (LE), is a condition characterized by the pain and tenderness over the lateral epicondyle of the humerus. LE is commonly seen among people who are involved in sports such as tennis and golf. Any activity that repeatedly overstrains the extensor carpi radialis brevis tendon can lead to LE. The management of lateral epicondylitis generally involves the use of counterforce orthosis. The aim of this review is to summarize the evidence regarding the effectiveness of counterforce orthoses on the clinical outcomes of patients with lateral epicondylitis. The PubMed, Ovid, and ProQuest databases were searched for potential studies which explored the use of counterforce orthosis in the management of lateral epicondylitis. To have a better understanding of the effectiveness of various types of orthoses, the review is organized into four sections. The first section explores the use of a single orthotic device, the second section focuses on the combined use of orthotic devices, the third section explore studies that compared the effect of local steroid injection along with orthosis and the last section narrate the studies that compared various types of orthotic devices. The studies support the use of orthotic devices as a treatment modality for lateral epicondylitis. There is rising evidence which supports the use of a comprehensive approach, (by combining routine physiotherapy with orthotic devices) in the management of LE. Orthosis alone or in combination with routine physical therapy can be considered as an evidence-based treatment strategy for patients with lateral epicondylitis. However, on the basis of the literature review conducted, the authors recommend that further high-quality clinical trials regarding the management of lateral epicondylitis are necessary to strengthen the evidence-based physiotherapy practice.

Foot placement in robotic bipedal locomotion

NARCIS (Netherlands)

De Boer, T.

2012-01-01

Human walking is remarkably robust, versatile and energy-efficient: humans have the ability to handle large unexpected disturbances, perform a wide variety of gaits and consume little energy. A bipedal walking robot that performs well on all of these aspects has not yet been developed. Some robots

Gait Selection and Transition of Passivity-Based Bipeds with Adaptable Ankle Stiffness

Directory of Open Access Journals (Sweden)

Yan Huang

2012-10-01

Full Text Available Stable bipedal walking is one of the most important components of humanoid robot design, which can help us better understand natural human walking. In this paper, to study gait selection and gait transition of efficient bipedal walking, we proposed a dynamic bipedal walking model with an upper body, flat feet and compliant joints. The model can achieve stable cyclic motion with different walking gaits. The hip actuation and ankle stiffness behavior of the model are quite similar to those of human normal walking. In simulation, we studied the influence of hip actuation and ankle stiffness on walking performance of each gait. The effects of ankle stiffness on gait selection are also analyzed. Gait transition is realized by adjusting ankle stiffness during walking.

Combination of brain-computer interface training and goal-directed physical therapy in chronic stroke: a case report.

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Broetz, Doris; Braun, Christoph; Weber, Cornelia; Soekadar, Surjo R; Caria, Andrea; Birbaumer, Niels

2010-09-01

There is no accepted and efficient rehabilitation strategy to reduce focal impairments for patients with chronic stroke who lack residual movements. A 67-year-old hemiplegic patient with no active finger extension was trained with a brain-computer interface (BCI) combined with a specific daily life-oriented physiotherapy. The BCI used electrical brain activity (EEG) and magnetic brain activity (MEG) to drive an orthosis and a robot affixed to the patient's affected upper extremity, which enabled him to move the paralyzed arm and hand driven by voluntary modulation of micro-rhythm activity. In addition, the patient practiced goal-directed physiotherapy training. Over 1 year, he completed 3 training blocks. Arm motor function, gait capacities (using Fugl-Meyer Assessment, Wolf Motor Function Test, Modified Ashworth Scale, 10-m walk speed, and goal attainment score), and brain reorganization (functional MRI, MEG) were repeatedly assessed. The ability of hand and arm movements as well as speed and safety of gait improved significantly (mean 46.6%). Improvement of motor function was associated with increased micro-oscillations in the ipsilesional motor cortex. This proof-of-principle study suggests that the combination of BCI training with goal-directed, active physical therapy may improve the motor abilities of chronic stroke patients despite apparent initial paralysis.

Use and tolerability of a side pole static ankle foot orthosis in children with neurological disorders.

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Delvert, Céline; Rippert, Pascal; Margirier, Françoise; Vadot, Jean-Pierre; Bérard, Carole; Poirot, Isabelle; Vuillerot, Carole

2017-04-01

Transverse-plane foot deformities are a frequently encountered issue in children with neurological disorders. They are the source of many symptoms, such as pain and walking difficulties, making their prevention very important. We aim to describe the use and tolerability of a side pole static ankle foot orthosis used to prevent transverse-plane foot deformities in children with neurologic disorders. Monocentric, retrospective, observational study. Medical data were collected from 103 children with transverse-plane foot deformities in one or both feet caused by a neurological impairment. All children were braced between 2001 and 2010. Unilateral orthosis was prescribed for 32 children and bilateral orthosis for 71. Transverse-plane foot deformities were varus in 66% of the cases and an equinus was associated in 59.2% of the cases. Mean age for the first prescription was 8.6 years. For the 23 patients present at the 4-year visit, 84.8% still wore the orthosis daily, and 64.7% wore the orthosis more than 6 h per day. The rate of permanent discontinuation of wearing the orthosis was 14.7%. The side pole static ankle foot orthosis is well tolerated with very few side effects, which promotes regular wearing and observance. Clinical relevance Side pole static ankle foot orthoses are well tolerated and can be safely used for children with foot abnormalities in the frontal plane that have a neurological pathology origin.

Increased lower limb muscle coactivation reduces gait performance and increases metabolic cost in patients with hereditary spastic paraparesis.

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Rinaldi, Martina; Ranavolo, Alberto; Conforto, Silvia; Martino, Giovanni; Draicchio, Francesco; Conte, Carmela; Varrecchia, Tiwana; Bini, Fabiano; Casali, Carlo; Pierelli, Francesco; Serrao, Mariano

2017-10-01

The aim of this study was to investigate the lower limb muscle coactivation and its relationship with muscles spasticity, gait performance, and metabolic cost in patients with hereditary spastic paraparesis. Kinematic, kinetic, electromyographic and energetic parameters of 23 patients and 23 controls were evaluated by computerized gait analysis system. We computed ankle and knee antagonist muscle coactivation indexes throughout the gait cycle and during the subphases of gait. Energy consumption and energy recovery were measured as well. In addition to the correlation analysis between coactivation indexes and clinical variables, correlations between coactivation indexes and time-distance, kinematic, kinetic, and energetic parameters were estimated. Increased coactivity indexes of both knee and ankle muscles throughout the gait cycle and during the subphases of gait were observed in patients compared with controls. Energetic parameters were significantly higher in patients than in controls. Both knee and ankle muscle coactivation indexes were positively correlated with knee and ankle spasticity (Ashworth score), respectively. Knee and ankle muscle coactivation indexes were both positively correlated with energy consumption and both negatively correlated with energy recovery. Positive correlations between the Ashworth score and lower limb muscle coactivation suggest that abnormal lower limb muscle coactivation in patients with hereditary spastic paraparesis reflects a primary deficit linked to lower limb spasticity. Furthermore, these abnormalities influence the energetic mechanisms during walking. Identifying excessive muscle coactivation may be helpful in individuating the rehabilitative treatments and designing specific orthosis to restrain spasticity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Strategies for human-driven robot comprehension of spatial descriptions by older adults in a robot fetch task.

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Carlson, Laura; Skubic, Marjorie; Miller, Jared; Huo, Zhiyu; Alexenko, Tatiana

2014-07-01

This contribution presents a corpus of spatial descriptions and describes the development of a human-driven spatial language robot system for their comprehension. The domain of application is an eldercare setting in which an assistive robot is asked to "fetch" an object for an elderly resident based on a natural language spatial description given by the resident. In Part One, we describe a corpus of naturally occurring descriptions elicited from a group of older adults within a virtual 3D home that simulates the eldercare setting. We contrast descriptions elicited when participants offered descriptions to a human versus robot avatar, and under instructions to tell the addressee how to find the target versus where the target is. We summarize the key features of the spatial descriptions, including their dynamic versus static nature and the perspective adopted by the speaker. In Part Two, we discuss critical cognitive and perceptual processing capabilities necessary for the robot to establish a common ground with the human user and perform the "fetch" task. Based on the collected corpus, we focus here on resolving the perspective ambiguity and recognizing furniture items used as landmarks in the descriptions. Taken together, the work presented here offers the key building blocks of a robust system that takes as input natural spatial language descriptions and produces commands that drive the robot to successfully fetch objects within our eldercare scenario. Copyright © 2014 Cognitive Science Society, Inc.

Active lower limb orthosis with one degree of freedom for people with paraplegia.

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Gloger, Michal; Obinata, Goro; Genda, Eiichi; Babjak, Jan; Pei, Yanling

2017-07-01

The main challenges of designing devices for paraplegic walking can be summarized into three groups, stability and comfort, high efficiency or low energy consumption, dimensions and weight. A new economical device for people with paraplegia which tackles all problems of the three groups is introduced in this paper. The main idea of this device is based on HALO mechanism. HALO is compact passive medial hip joint orthosis with contralateral hip and ankle linkage, which keeps the feet always parallel to the ground and assists swinging the leg. The medial hip joint is equipped with one actuator in the new design and the new orthosis is called @halo. Due to this update, we can achieve more stable and smoother walking patterns with decreased energy consumption of the users, yet maintain its compact and lightweight features. It is proven by the results from preliminary experiments with able-bodied subjects during which the same device with and without actuator was evaluated. Waddling and excessive vertical elevation of the center of gravity were decreased by 40% with significantly smaller standard deviations in case of the active orthosis. There was 52% less energy spent by the user wearing @halo which was calculated from the vertical excursion difference. There was measured 38.5% bigger impulse in crutches while using passive orthosis. The new @halo device is the first active orthosis for lower limbs with just one actuated degree of freedom for users with paraplegia.

Fusion reactor handling operations with cable-driven parallel robots

Energy Technology Data Exchange (ETDEWEB)

Izard, Jean-Baptiste, E-mail: jeanbaptiste.izard@tecnalia.com; Michelin, Micael; Baradat, Cédric

2015-10-15

Highlights: • CDPR allow 6DOF positioning of loads using cable as links without payload swag. • Conceptual design of a CDPR for carrying and positioning tokamak sectors is given. • A CDPR for threading stellarator coils (6D trajectory following) is provided. • Both designs are capable of fullfilling the required precision without tooling. - Abstract: Cable-driven parallel robots (CDPR) are in their concept cranes with inclined cables which allow control of all the degrees of freedom of its payload, and therefore stability of all the degrees of freedom, including rotations. The workspace of a CDPR is only limited by the length of the cables, and the payload capacity related to the mass of the whole robot is very important. Besides, the control being based on kinematic models, the behavior of a CDPR is really that of a robot capable of automated trajectories or remote handling. The present paper gives a presentation of two use case studies based on some of the assembly phases and remote handling actions as designed for the recent fusion machines. Based on the use cases already in place in fusion reactor baselines, the opportunity of using CDPR for assembly of structural elements and coils is discussed. Finally, prospects for remote handling equipment from the reactor in hot cells are envisioned based on current CDPR research.

A robot and control algorithm that can synchronously assist in naturalistic motion during body-weight-supported gait training following neurologic injury.

Science.gov (United States)

Aoyagi, Daisuke; Ichinose, Wade E; Harkema, Susan J; Reinkensmeyer, David J; Bobrow, James E

2007-09-01

Locomotor training using body weight support on a treadmill and manual assistance is a promising rehabilitation technique following neurological injuries, such as spinal cord injury (SCI) and stroke. Previous robots that automate this technique impose constraints on naturalistic walking due to their kinematic structure, and are typically operated in a stiff mode, limiting the ability of the patient or human trainer to influence the stepping pattern. We developed a pneumatic gait training robot that allows for a full range of natural motion of the legs and pelvis during treadmill walking, and provides compliant assistance. However, we observed an unexpected consequence of the device's compliance: unimpaired and SCI individuals invariably began walking out-of-phase with the device. Thus, the robot perturbed rather than assisted stepping. To address this problem, we developed a novel algorithm that synchronizes the device in real-time to the actual motion of the individual by sensing the state error and adjusting the replay timing to reduce this error. This paper describes data from experiments with individuals with SCI that demonstrate the effectiveness of the synchronization algorithm, and the potential of the device for relieving the trainers of strenuous work while maintaining naturalistic stepping.

Exoskeleton-assisted gait training to improve gait in individuals with spinal cord injury: a pilot randomized study.

Science.gov (United States)

Chang, Shuo-Hsiu; Afzal, Taimoor; Berliner, Jeffrey; Francisco, Gerard E

2018-01-01

Robotic wearable exoskeletons have been utilized as a gait training device in persons with spinal cord injury. This pilot study investigated the feasibility of offering exoskeleton-assisted gait training (EGT) on gait in individuals with incomplete spinal cord injury (iSCI) in preparation for a phase III RCT. The objective was to assess treatment reliability and potential efficacy of EGT and conventional physical therapy (CPT). Forty-four individuals were screened, and 13 were eligible to participate in the study. Nine participants consented and were randomly assigned to receive either EGT or CPT with focus on gait. Subjects received EGT or CPT, five sessions a week (1 h/session daily) for 3 weeks. American Spinal Injury Association (ASIA) Lower Extremity Motor Score (LEMS), 10-Meter Walk Test (10MWT), 6-Minute Walk Test (6MWT), Timed Up and Go (TUG) test, and gait characteristics including stride and step length, cadence and stance, and swing phase durations were assessed at the pre- and immediate post- training. Mean difference estimates with 95% confidence intervals were used to analyze the differences. After training, improvement was observed in the 6MWT for the EGT group. The CPT group showed significant improvement in the TUG test. Both the EGT and the CPT groups showed significant increase in the right step length. EGT group also showed improvement in the stride length. EGT could be applied to individuals with iSCI to facilitate gait recovery. The subjects were able to tolerate the treatment; however, exoskeleton size range may be a limiting factor in recruiting larger cohort of patients. Future studies with larger sample size are needed to investigate the effectiveness and efficacy of exoskeleton-assisted gait training as single gait training and combined with other gait training strategies. Clinicaltrials.org, NCT03011099, retrospectively registered on January 3, 2017.

[Kinematics Modeling and Analysis of Central-driven Robot for Upper Limb Rehabilitation after Stroke].

Science.gov (United States)

Yi, Jinhua; Yu, Hongliu; Zhang, Ying; Hu, Xin; Shi, Ping

2015-12-01

The present paper proposed a central-driven structure of upper limb rehabilitation robot in order to reduce the volume of the robotic arm in the structure, and also to reduce the influence of motor noise, radiation and other adverse factors on upper limb dysfunction patient. The forward and inverse kinematics equations have been obtained with using the Denavit-Hartenberg (D-H) parameter method. The motion simulation has been done to obtain the angle-time curve of each joint and the position-time curve of handle under setting rehabilitation path by using Solid Works software. Experimental results showed that the rationality with the central-driven structure design had been verified by the fact that the handle could move under setting rehabilitation path. The effectiveness of kinematics equations had been proved, and the error was less than 3° by comparing the angle-time curves obtained from calculation with those from motion simulation.

Simple analytical model reveals the functional role of embodied sensorimotor interaction in hexapod gaits

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Aoi, Shinya; Nachstedt, Timo; Manoonpong, Poramate; Wörgötter, Florentin; Matsuno, Fumitoshi

2018-01-01

Insects have various gaits with specific characteristics and can change their gaits smoothly in accordance with their speed. These gaits emerge from the embodied sensorimotor interactions that occur between the insect’s neural control and body dynamic systems through sensory feedback. Sensory feedback plays a critical role in coordinated movements such as locomotion, particularly in stick insects. While many previously developed insect models can generate different insect gaits, the functional role of embodied sensorimotor interactions in the interlimb coordination of insects remains unclear because of their complexity. In this study, we propose a simple physical model that is amenable to mathematical analysis to explain the functional role of these interactions clearly. We focus on a foot contact sensory feedback called phase resetting, which regulates leg retraction timing based on touchdown information. First, we used a hexapod robot to determine whether the distributed decoupled oscillators used for legs with the sensory feedback generate insect-like gaits through embodied sensorimotor interactions. The robot generated two different gaits and one had similar characteristics to insect gaits. Next, we proposed the simple model as a minimal model that allowed us to analyze and explain the gait mechanism through the embodied sensorimotor interactions. The simple model consists of a rigid body with massless springs acting as legs, where the legs are controlled using oscillator phases with phase resetting, and the governed equations are reduced such that they can be explained using only the oscillator phases with some approximations. This simplicity leads to analytical solutions for the hexapod gaits via perturbation analysis, despite the complexity of the embodied sensorimotor interactions. This is the first study to provide an analytical model for insect gaits under these interaction conditions. Our results clarified how this specific foot contact sensory

Origami-based earthworm-like locomotion robots.

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Fang, Hongbin; Zhang, Yetong; Wang, K W

2017-10-16

Inspired by the morphology characteristics of the earthworms and the excellent deformability of origami structures, this research creates a novel earthworm-like locomotion robot through exploiting the origami techniques. In this innovation, appropriate actuation mechanisms are incorporated with origami ball structures into the earthworm-like robot 'body', and the earthworm's locomotion mechanism is mimicked to develop a gait generator as the robot 'centralized controller'. The origami ball, which is a periodic repetition of waterbomb units, could output significant bidirectional (axial and radial) deformations in an antagonistic way similar to the earthworm's body segment. Such bidirectional deformability can be strategically programmed by designing the number of constituent units. Experiments also indicate that the origami ball possesses two outstanding mechanical properties that are beneficial to robot development: one is the structural multistability in the axil direction that could contribute to the robot control implementation; and the other is the structural compliance in the radial direction that would increase the robot robustness and applicability. To validate the origami-based innovation, this research designs and constructs three robot segments based on different axial actuators: DC-motor, shape-memory-alloy springs, and pneumatic balloon. Performance evaluations reveal their merits and limitations, and to prove the concept, the DC-motor actuation is selected for building a six-segment robot prototype. Learning from earthworms' fundamental locomotion mechanism-retrograde peristalsis wave, seven gaits are automatically generated; controlled by which, the robot could achieve effective locomotion with qualitatively different modes and a wide range of average speeds. The outcomes of this research could lead to the development of origami locomotion robots with low fabrication costs, high customizability, light weight, good scalability, and excellent re-configurability.

Optimal Orientation Planning and Control Deviation Estimation on FAST Cable-Driven Parallel Robot

Directory of Open Access Journals (Sweden)

Hui Li

2014-03-01

Full Text Available The paper is devoted theoretically to the optimal orientation planning and control deviation estimation of FAST cable-driven parallel robot. Regarding the robot characteristics, the solutions are obtained from two constrained optimizations, both of which are based on the equilibrium of the cabin and the attention on force allocation among 6 cable tensions. A kind of control algorithm is proposed based on the position and force feedbacks. The analysis proves that the orientation control depends on force feedback and the optimal tension solution corresponding to the planned orientation. Finally, the estimation of orientation deviation is given under the limit range of tension errors.

Combining Environment-Driven Adaptation and Task-Driven Optimisation in Evolutionary Robotics

NARCIS (Netherlands)

Haasdijk, E.W.; Bredeche, Nicolas; Eiben, A.E.

2014-01-01

Embodied evolutionary robotics is a sub-field of evolutionary robotics that employs evolutionary algorithms on the robotic hardware itself, during the operational period, i.e., in an on-line fashion. This enables robotic systems that continuously adapt, and are therefore capable of (re-)adjusting

Restoration of ankle movements with the ActiGait implantable drop foot stimulator: a safe and reliable treatment option for permanent central leg palsy.

Science.gov (United States)

Martin, Klaus Daniel; Polanski, Witold Henryk; Schulz, Anne-Kathrin; Jöbges, Michael; Hoff, Hansjoerg; Schackert, Gabriele; Pinzer, Thomas; Sobottka, Stephan B

2016-01-01

OBJECT The ActiGait drop foot stimulator is a promising technique for restoration of lost ankle function by an implantable hybrid stimulation system. It allows ankle dorsiflexion by active peroneal nerve stimulation during the swing phase of gait. In this paper the authors report the outcome of the first prospective study on a large number of patients with stroke-related drop foot. METHODS Twenty-seven patients who experienced a stroke and with persisting spastic leg paresis received an implantable ActiGait drop foot stimulator for restoration of ankle movement after successful surface test stimulation. After 3 to 5 weeks, the stimulator was activated, and gait speed, gait endurance, and activation time of the system were evaluated and compared with preoperative gait tests. In addition, patient satisfaction was assessed using a questionnaire. RESULTS Postoperative gait speed significantly improved from 33.9 seconds per 20 meters to 17.9 seconds per 20 meters (p < 0.0001), gait endurance from 196 meters in 6 minutes to 401 meters in 6 minutes (p < 0.0001), and activation time from 20.5 seconds to 10.6 seconds on average (p < 0.0001). In 2 patients with nerve injury, surgical repositioning of the electrode cuff became necessary. One patient showed a delayed wound healing, and in another patient the system had to be removed because of a wound infection. Marked improvement in mobility, social participation, and quality of life was confirmed by 89% to 96% of patients. CONCLUSIONS The ActiGait implantable drop foot stimulator improves gait speed, endurance, and quality of life in patients with stroke-related drop foot. Regarding gait speed, the ActiGait system appears to be advantageous compared with foot orthosis or surface stimulation devices. Randomized trials with more patients and longer observation periods are needed to prove the long-term benefit of this device.

iGrab: hand orthosis powered by twisted and coiled polymer muscles

Science.gov (United States)

Saharan, Lokesh; de Andrade, Monica Jung; Saleem, Wahaj; Baughman, Ray H.; Tadesse, Yonas

2017-10-01

Several works have been reported in powered hand orthosis in the last ten years for assistive or rehabilitative purposes. However, most of these approaches uses conventional actuators such as servo motors to power orthosis. In this work, we demonstrate the recently reported twisted and coiled polymeric (TCP) muscles to drive a compact, light, inexpensive and wearable upper extremity device, iGrab. A 3D printed orthotic hand module was designed, developed and tested for the performance. The device has six 2-ply muscles of diameter 1.35 mm with a length of 380 mm. We used a single 2-ply muscle for each finger and two 2-ply muscles for the thumb. Pulsed actuation of the muscles at 1.8 A current for 25 s with 7% duty cycle under natural cooling showed full flexion of the fingers within 2 s. Modeling and simulation were performed on the device using standard Euler-Lagrangian equations. Our artificial muscles powered hand orthosis demonstrated the capability of pinching and picking objects of different shapes, weights, and sizes.

Gait control by foot placement for humanoid robots

NARCIS (Netherlands)

Botden, F.J.B.M.; Nijmeijer, H.; Zutven, van P.W.M.

2013-01-01

Humanoid robots are used as a research tool to understand bipedal locomotion. When pushed, a humanoid robot must be able to avoid falling and return to a balanced configuration. This is called push recovery and can be achieved using proper foot placement. Depending on the freedom of movement, one or

Evaluation of a Virtual Model Control for the selective support of gait functions using an exoskeleton

NARCIS (Netherlands)

Ekkelenkamp, R.; Ekkelenkamp, R.; Veltink, Petrus H.; Stramigioli, Stefano; van der Kooij, Herman

Robotic gait trainers are used all over the world for the rehabilitation of stroke patients, despite relatively little is known about how the robots should be controlled to achieve the optimal improvement. Most devices control complete joint trajectories and assume symmetry between both legs by

Biological inspiration used for robots motion synthesis.

Science.gov (United States)

Zielińska, Teresa

2009-01-01

This work presents a biologically inspired method of gait generation. Bipedal gait pattern (for hip and knee joints) was taken into account giving the reference trajectories in a learning task. The four coupled oscillators were taught to generate the outputs similar to those in a human gait. After applying the correction functions the obtained generation method was validated using ZMP criterion. The formula suitable for real-time motion generation taking into account the positioning errors was also formulated. The small real robot prototype was tested to be able walk successfully following the elaborated motion pattern.

Wearable Gait Measurement System with an Instrumented Cane for Exoskeleton Control

Directory of Open Access Journals (Sweden)

Modar Hassan

2014-01-01

Full Text Available In this research we introduce a wearable sensory system for motion intention estimation and control of exoskeleton robot. The system comprises wearable inertial motion sensors and shoe-embedded force sensors. The system utilizes an instrumented cane as a part of the interface between the user and the robot. The cane reflects the motion of upper limbs, and is used in terms of human inter-limb synergies. The developed control system provides assisted motion in coherence with the motion of other unassisted limbs. The system utilizes the instrumented cane together with body worn sensors, and provides assistance for start, stop and continuous walking. We verified the function of the proposed method and the developed wearable system through gait trials on treadmill and on ground. The achievement contributes to finding an intuitive and feasible interface between human and robot through wearable gait sensors for practical use of assistive technology. It also contributes to the technology for cognitively assisted locomotion, which helps the locomotion of physically challenged people.

Single DoF Hand Orthosis for Rehabilitation of Stroke and SCI Patients

Science.gov (United States)

Kannan Megalingam, Rajesh; Apuroop, K. G. S.; Boddupalli, Sricharan

2017-08-01

Many stroke and spinal cord injury patients suffer from paralysis which range from severe to nominal. Some of them, after therapy, could regain most of the motor control, particularly in hands if the severity level is not so high. In this paper we propose a hand orthosis for such patients whose stroke and spinal cord injury severity is nominal and the motor control in hands can be regained by therapy as part of their rehabilitation process. The patients can wear this orthosis and the therapy can be done with simple Human Computer Interface. The physicians, the physiotherapists and the patients themselves can carry out the therapy with the help of this device. The tests conducted in the lab and the results obtained are very promising that this can be an effective mechanism for stroke and spinal cord injury patients in their rehabilitation process. The hand orthosis is designed and fabricated locally so that it can be made available to such patients at an affordable cost.

An Approach to Stable Walking over Uneven Terrain Using a Reflex-Based Adaptive Gait

Directory of Open Access Journals (Sweden)

Umar Asif

2011-01-01

Full Text Available This paper describes the implementation of an adaptive gait in a six-legged walking robot that is capable of generating reactive stepping actions with the same underlying control methodology as an insect for stable walking over uneven terrains. The proposed method of gait generation uses feedback data from onboard sensors to generate an adaptive gait in order to surmount obstacles, gaps and perform stable walking. The paper addresses its implementation through simulations in a visual dynamic simulation environment. Finally the paper draws conclusions about the significance and performance of the proposed gait in terms of tracking errors while navigating in difficult terrains.

Numerical Modelling and Simulation of Dynamic Parameters for Vibration Driven Mobile Robot: Preliminary Study

Science.gov (United States)

Baharudin, M. E.; Nor, A. M.; Saad, A. R. M.; Yusof, A. M.

2018-03-01

The motion of vibration-driven robots is based on an internal oscillating mass which can move without legs or wheels. The oscillation of the unbalanced mass by a motor is translated into vibration which in turn produces vertical and horizontal forces. Both vertical and horizontal oscillations are of the same frequency but the phases are shifted. The vertical forces will deflect the bristles which cause the robot to move forward. In this paper, the horizontal motion direction caused by the vertically vibrated bristle is numerically simulated by tuning the frequency of their oscillatory actuation. As a preliminary work, basic equations for a simple off-centered vibration location on the robot platform and simulation model for vibration excitement are introduced. It involves both static and dynamic vibration analysis of robots and analysis of different type of parameters. In addition, the orientation of the bristles and oscillators are also analysed. Results from the numerical integration seem to be in good agreement with those achieved from the literature. The presented numerical integration modeling can be used for designing the bristles and controlling the speed and direction of the robot.

Trajectory generation to suppress oscillations in under-constrained cable-driven parallel robots

Energy Technology Data Exchange (ETDEWEB)

Hwang, Sung Wook; Bak, Jeong Hyeon; Yoon, Jong Hyun; Park, Jong Hyeon [Dept. of Mechanical Engineering, Hanyang University, Seoul (Korea, Republic of); Park, Jong Oh [School of Mechanical Engineering, Chonnam National University, Gwangju (Korea, Republic of)

2016-12-15

Cable-driven parallel robots (CDPRs) have many advantages over conventional link-based robot manipulators in terms of acceleration due to their low inertia. This paper concerns about under-constrained CDPRs, which have a less number of cables than six, often used favorably due to their simpler structures. Since a smaller number of cables than 6 are employed, however, their payloads have extra degrees of motion freedom and exhibit swaying motions or oscillation. In this paper, a scheme to suppress unwanted oscillatory motions of the payload of a 4-cable-driven CDPR based on a Zero-vibration (ZV) input-shaping scheme is proposed. In this method, a motion in the 3-dimensional space is projected onto the independent motions on two vertical planes perpendicular to each other. On each of the vertical plane, the natural frequency of the CDPR is computed based on a 2-cable-driven planar CDPR model. The precise dynamic model of a planar CDPR is obtained in order to find the natural frequency, which depends on the payload position. The advantage of the proposed scheme is that it is possible to generate an oscillation-free trajectory based on a ZV input-shaping scheme despite the complexity in the dynamics of the CDPR and the difficulty in computing the natural frequencies of the CDPR, which is required in any ZV input-shaping scheme. To verify the effectiveness of the proposed method, a series of computer simulations and experiments were conducted for 3- dimensional motions with a 4-cable-driven CDPR. Their results showed that the motions of the CDPR with the proposed method exhibited a significant reduction in oscillations of the payload. However, when the payload moves near the edges of its workspace, the improvement in oscillation reduction diminished as expected due to the errors in model projection.

Plasticity of spinal centers in spinal cord injury patients: new concepts for gait evaluation and training.

Science.gov (United States)

Scivoletto, Giorgio; Ivanenko, Yuri; Morganti, Barbara; Grasso, Renato; Zago, Mirka; Lacquaniti, Francesco; Ditunno, John; Molinari, Marco

2007-01-01

Recent data on spinal cord plasticity after spinal cord injury (SCI) were reviewed to analyze the influence of training on the neurophysiological organization of locomotor spinal circuits in SCI patients. In particular, the authors studied the relationship between central pattern generators (CPGs) and motor neuron pool activation during gait. An analysis of the relations between locomotor recovery and compensatory mechanisms focuses on the hierarchical organization of gait parameters and allows characterizing kinematic parameters that are highly stable during different gait conditions and in recovered gait after SCI. The importance of training characteristics and the use of robotic/automated devices in gait recovery is analyzed and discussed. The role of CPG in defining kinematic gait parameters is summarized, and spatio-temporal maps of EMG activity during gait are used to clarify the role of CPG plasticity in sustaining gait recovery.

A Newly Designed Tennis Elbow Orthosis With a Traditional Tennis Elbow Strap in Patients With Lateral Epicondylitis

Science.gov (United States)

Saremi, Hossein; Chamani, Vahid; Vahab-Kashani, Reza

2016-01-01

Background Lateral epicondylitis is a common cause of pain and upper limb dysfunction. The use of counterforce straps for treatment of lateral epicondylitis is widespread. This kind of orthosis can be modified to have a greater effect on relieving pain by reducing tension on the origin of the extensor pronator muscles. Objectives To determine the immediate effects of a newly designed orthosis on pain and grip strength in patients with lateral epicondylitis. Materials and Methods Twelve participants (six men and six women) were recruited (mean age = 41 ± 6.7 years) and evaluated for pain and grip strength in three sessions. A 48-hour break was taken between each session. The first session was without any orthosis, the second session was with the new modified tennis elbow orthosis, and the third session was with a conventional tennis elbow strap. Results Both counterforce straps were effective. However, significantly more improvement was observed in pain and grip strength after using the newly modified orthosis (P < 0.05). Conclusions The newly designed strap reduces pain more effectively and improves grip strength by causing greater localized pressure on two regions with different force applications (two component vectors versus one). PMID:28180116

A Newly Designed Tennis Elbow Orthosis With a Traditional Tennis Elbow Strap in Patients With Lateral Epicondylitis.

Science.gov (United States)

Saremi, Hossein; Chamani, Vahid; Vahab-Kashani, Reza

2016-07-01

Lateral epicondylitis is a common cause of pain and upper limb dysfunction. The use of counterforce straps for treatment of lateral epicondylitis is widespread. This kind of orthosis can be modified to have a greater effect on relieving pain by reducing tension on the origin of the extensor pronator muscles. To determine the immediate effects of a newly designed orthosis on pain and grip strength in patients with lateral epicondylitis. Twelve participants (six men and six women) were recruited (mean age = 41 ± 6.7 years) and evaluated for pain and grip strength in three sessions. A 48-hour break was taken between each session. The first session was without any orthosis, the second session was with the new modified tennis elbow orthosis, and the third session was with a conventional tennis elbow strap. Both counterforce straps were effective. However, significantly more improvement was observed in pain and grip strength after using the newly modified orthosis (P < 0.05). The newly designed strap reduces pain more effectively and improves grip strength by causing greater localized pressure on two regions with different force applications (two component vectors versus one).

Goal driven kinematic simulation of flexible arm robot for space station missions

Science.gov (United States)

Janssen, P.; Choudry, A.

1987-01-01

Flexible arms offer a great degree of flexibility in maneuvering in the space environment. The problem of transporting an astronaut for extra-vehicular activity using a space station based flexible arm robot was studied. Inverse kinematic solutions of the multilink structure were developed. The technique is goal driven and can support decision making for configuration selection as required for stability and obstacle avoidance. Details of this technique and results are given.

Biped Robot Gait Planning Based on 3D Linear Inverted Pendulum Model

Science.gov (United States)

Yu, Guochen; Zhang, Jiapeng; Bo, Wu

2018-01-01

In order to optimize the biped robot’s gait, the biped robot’s walking motion is simplify to the 3D linear inverted pendulum motion mode. The Center of Mass (CoM) locus is determined from the relationship between CoM and the Zero Moment Point (ZMP) locus. The ZMP locus is planned in advance. Then, the forward gait and lateral gait are simplified as connecting rod structure. Swing leg trajectory using B-spline interpolation. And the stability of the walking process is discussed in conjunction with the ZMP equation. Finally the system simulation is carried out under the given conditions to verify the validity of the proposed planning method.

An Intention-Driven Semi-autonomous Intelligent Robotic System for Drinking

Directory of Open Access Journals (Sweden)

Zhijun Zhang

2017-09-01

Full Text Available In this study, an intention-driven semi-autonomous intelligent robotic (ID-SIR system is designed and developed to assist the severely disabled patients to live independently. The system mainly consists of a non-invasive brain–machine interface (BMI subsystem, a robot manipulator and a visual detection and localization subsystem. Different from most of the existing systems remotely controlled by joystick, head- or eye tracking, the proposed ID-SIR system directly acquires the intention from users’ brain. Compared with the state-of-art system only working for a specific object in a fixed place, the designed ID-SIR system can grasp any desired object in a random place chosen by a user and deliver it to his/her mouth automatically. As one of the main advantages of the ID-SIR system, the patient is only required to send one intention command for one drinking task and the autonomous robot would finish the rest of specific controlling tasks, which greatly eases the burden on patients. Eight healthy subjects attended our experiment, which contained 10 tasks for each subject. In each task, the proposed ID-SIR system delivered the desired beverage container to the mouth of the subject and then put it back to the original position. The mean accuracy of the eight subjects was 97.5%, which demonstrated the effectiveness of the ID-SIR system.

The mechanics of redundantly-driven robotic systems. Final report, September 1988 - December 1995

International Nuclear Information System (INIS)

Tsai, L.W.

1996-04-01

The objectives of this research are to develop systematic methodologies for the creation of multi-degree-of-freedom mechanisms and to gain better understanding of the kinematics, dynamics and control of such devices. The following three inter-related subjects have been studied: (1) tendon-driven manipulators, (2) geared robotic mechanisms, and (3) automotive transmission mechanisms. The main results of this study are summarized

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients.

Science.gov (United States)

Hesse, Stefan; Waldner, Andreas; Tomelleri, Christopher

2010-06-28

Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged) onset (duration) of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies.

Design and experimental evaluation of a lightweight, high-torque and compliant actuator for an active ankle foot orthosis.

Science.gov (United States)

Moltedo, Marta; Bacek, Tomislav; Langlois, Kevin; Junius, Karen; Vanderborght, Bram; Lefeber, Dirk

2017-07-01

The human ankle joint plays a crucial role during walking. At the push-off phase the ankle plantarflexors generate the highest torque among the lower limb joints during this activity. The potential of the ankle plantarflexors is affected by numerous pathologies and injuries, which cause a decrease in the ability of the subject to achieve a natural gait pattern. Active orthoses have shown to have potential in assisting these subjects. The design of such robots is very challenging due to the contrasting design requirements of wearability (light weight and compact) and high torques capacity. This paper presents the development of a high-torque ankle actuator to assist the ankle joint in both dorsiflexion and plantarflexion. The compliant actuator is a spindle-driven MACCEPA (Mechanically Adjustable Compliance and Controllable Equilibrium Position Actuator). The design of the actuator was made to keep its weight as low as possible, while being able to provide high torques. As a result of this novel design, the actuator weighs 1.18kg. Some static characterization tests were perfomed on the actuator and their results are shown in the paper.

Online Gait Learning for Modular Robots with Arbitrary Shapes and Sizes

NARCIS (Netherlands)

Weel, Berend; D'Angelo, M.; Haasdijk, Evert; Eiben, A. E.

2017-01-01

Evolutionary robotics using real hardware is currently restricted to evolving robot controllers, but the technology for evolvable morphologies is advancing quickly. Rapid prototyping (3D printing) and automated assembly are the main enablers of robotic systems where robot offspring can be produced

Light‐driven Nano­‐robotics - Invited Plenary Presentation, IEEE NANO 2016

DEFF Research Database (Denmark)

Glückstad, Jesper

) and pioneering their use in so-called lightdriven nano-robotics. Hence, the aim of our latest R&D is to combine advanced topology optimisation, 3D printing of functionalized materials and light manipulation to demonstrate a structure-mediated micro-tonano coupling paradigm for controlled operation of robotic...... tools overcoming the diffraction limit while still being optically visible and manoeuvrable. 2PP-fabrication can already today create intricate nano-features merged onto larger microstructures that, in turn, are steerable by dynamic light beams. Applying multiple independently controllable laser beam...... traps on these structures will enable real-time light-driven nanorobotics with six-degrees-of-freedom. This sets the stage for new discoveries using calibrated steering of optimally shaped and functionalized nano-tools at the subcellular level and in full 3D - not available in the scientifi c world...

New Jacobian Matrix and Equations of Motion for a 6 d.o.f Cable-Driven Robot

Directory of Open Access Journals (Sweden)

Ali Afshari

2007-03-01

Full Text Available In this paper, we introduce a new method and new motion variables to study kinematics and dynamics of a 6 d.o.f cable-driven robot. Using these new variables and Lagrange equations, we achieve new equations of motion which are different in appearance and several aspects from conventional equations usually used to study 6 d.o.f cable robots. Then, we introduce a new Jacobian matrix which expresses kinematical relations of the robot via a new approach and is basically different from the conventional Jacobian matrix. One of the important characteristics of the new method is computational efficiency in comparison with the conventional method. It is demonstrated that using the new method instead of the conventional one, significantly reduces the computation time required to determine workspace of the robot as well as the time required to solve the equations of motion.

Design and Programming for Cable-Driven Parallel Robots in the German Pavilion at the EXPO 2015

Directory of Open Access Journals (Sweden)

Philipp Tempel

2015-08-01

Full Text Available In the German Pavilion at the EXPO 2015, two large cable-driven parallel robots are flying over the heads of the visitors representing two bees flying over Germany and displaying everyday life in Germany. Each robot consists of a mobile platform and eight cables suspended by winches and follows a desired trajectory, which needs to be computed in advance taking technical limitations, safety considerations and visual aspects into account. In this paper, a path planning software is presented, which includes the design process from developing a robot design and workspace estimation via planning complex trajectories considering technical limitations through to exporting a complete show. For a test trajectory, simulation results are given, which display the relevant trajectories and cable force distributions.

Wearing an active spinal orthosis improves back extensor strength in women with osteoporotic vertebral fractures

DEFF Research Database (Denmark)

Valentin, Gitte Hoff; Pedersen, Louise Nymann; Maribo, Thomas

2014-01-01

.Study design:Experimental follow-up.Methods:The women used the active spinal orthosis for 3 months. Outcomes were changes in isometric back extensor strength, changes in back pain and changes in physical functioning.Results:A total of 13 women were included in the trial. Wearing the orthosis during a 3-month......Background:Vertebral fractures are the most common clinical manifestations of osteoporosis. Vertebral fractures and reduced back extensor strength can result in hyperkyphosis. Hyperkyphosis is associated with diminished daily functioning and an increased risk of falling. Improvements in back...... extensor strength can result in decreased kyphosis and thus a decreased risk of falls and fractures.Objectives:The aim was to examine the effects of an active spinal orthosis - Spinomed III - on back extensor strength, back pain and physical functioning in women with osteoporotic vertebral fractures...

Robotics in Lower-Limb Rehabilitation after Stroke.

Science.gov (United States)

Zhang, Xue; Yue, Zan; Wang, Jing

2017-01-01

With the increase in the elderly, stroke has become a common disease, often leading to motor dysfunction and even permanent disability. Lower-limb rehabilitation robots can help patients to carry out reasonable and effective training to improve the motor function of paralyzed extremity. In this paper, the developments of lower-limb rehabilitation robots in the past decades are reviewed. Specifically, we provide a classification, a comparison, and a design overview of the driving modes, training paradigm, and control strategy of the lower-limb rehabilitation robots in the reviewed literature. A brief review on the gait detection technology of lower-limb rehabilitation robots is also presented. Finally, we discuss the future directions of the lower-limb rehabilitation robots.

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients

Directory of Open Access Journals (Sweden)

Waldner Andreas

2010-06-01

Full Text Available Abstract Background Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk, based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. Methods The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. Results The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged onset (duration of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. Conclusions The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies.

The Combined Effects of Body Weight Support and Gait Speed on Gait Related Muscle Activity : A Comparison between Walking in the Lokomat Exoskeleton and Regular Treadmill Walking

NARCIS (Netherlands)

Van Kammen, Klaske; Boonstra, Annemarijke; Reinders-Messelink, Heleen; Otter, den Rob

2014-01-01

Background: For the development of specialized training protocols for robot assisted gait training, it is important to understand how the use of exoskeletons alters locomotor task demands, and how the nature and magnitude of these changes depend on training parameters. Therefore, the present study

Motor modules in robot-aided walking

Directory of Open Access Journals (Sweden)

Gizzi Leonardo

2012-10-01

Full Text Available Abstract Background It is hypothesized that locomotion is achieved by means of rhythm generating networks (central pattern generators and muscle activation generating networks. This modular organization can be partly identified from the analysis of the muscular activity by means of factorization algorithms. The activity of rhythm generating networks is described by activation signals whilst the muscle intervention generating network is represented by motor modules (muscle synergies. In this study, we extend the analysis of modular organization of walking to the case of robot-aided locomotion, at varying speed and body weight support level. Methods Non Negative Matrix Factorization was applied on surface electromyographic signals of 8 lower limb muscles of healthy subjects walking in gait robotic trainer at different walking velocities (1 to 3km/h and levels of body weight support (0 to 30%. Results The muscular activity of volunteers could be described by low dimensionality (4 modules, as for overground walking. Moreover, the activation signals during robot-aided walking were bursts of activation timed at specific phases of the gait cycle, underlying an impulsive controller, as also observed in overground walking. This modular organization was consistent across the investigated speeds, body weight support level, and subjects. Conclusions These results indicate that walking in a Lokomat robotic trainer is achieved by similar motor modules and activation signals as overground walking and thus supports the use of robotic training for re-establishing natural walking patterns.

Hybrid Locomotion Evaluation for a Novel Amphibious Spherical Robot

Directory of Open Access Journals (Sweden)

Huiming Xing

2018-01-01

Full Text Available We describe the novel, multiply gaited, vectored water-jet, hybrid locomotion-capable, amphibious spherical robot III (termed ASR-III featuring a wheel-legged, water-jet composite driving system incorporating a lifting and supporting wheel mechanism (LSWM and mechanical legs with a water-jet thruster. The LSWM allows the ASR-III to support the body and slide flexibly on smooth (flat terrain. The composite driving system facilitates two on-land locomotion modes (sliding and walking and underwater locomotion mode with vectored thrusters, improving adaptability to the amphibious environment. Sliding locomotion improves the stability and maneuverability of ASR-III on smooth flat terrain, whereas walking locomotion allows ASR-III to conquer rough terrain. We used both forward and reverse kinematic models to evaluate the walking and sliding gait efficiency. The robot can also realize underwater locomotion with four vectored water-jet thrusters, and is capable of forward motion, heading angle control and depth control. We evaluated LSWM efficiency and the sliding velocities associated with varying extensions of the LSWM. To explore gait stability and mobility, we performed on-land experiments on smooth flat terrain to define the optimal stride length and frequency. We also evaluated the efficacy of waypoint tracking when the sliding gait was employed, using a closed-loop proportional-integral-derivative (PID control mechanism. Moreover, experiments of forward locomotion, heading angle control and depth control were conducted to verify the underwater performance of ASR-III. Comparison of the previous robot and ASR-III demonstrated the ASR-III had better amphibious motion performance.

An Open-Structure Treadmill Gait Trainer: From Research to Application.

Science.gov (United States)

Li, Jian; Chen, Diansheng; Fan, Yubo

2017-01-01

Lower limb rehabilitation robots are designed to enhance gait function in individuals with motor impairments. Although numerous rehabilitation robots have been developed, only few of these robots have been used in practical health care, particularly in China. The objective of this study is to construct a lower limb rehabilitation robot and bridge the gap between research and application. Open structure to facilitate practical application was created for the whole robot. Three typical movement patterns of a single leg were adopted in designing the exoskeletons, and force models for patient training were established and analyzed under three different conditions, respectively, and then a control system and security strategy were introduced. After establishing the robot, a preliminary experiment on the actual use of a prototype by patients was conducted to validate the functionality of the robot. The experiment showed that different patients and stages displayed different performances, and results on the trend variations across patients and across stages confirmed the validity of the robot and suggested that the design may lead to a system that could be successful in the treatment of patients with walking disorders in China. Furthermore, this study could provide a reference for a similar application design.

Dynamic Modelling of a CPG-Controlled Amphibious Biomimetic Swimming Robot

Directory of Open Access Journals (Sweden)

Rui Ding

2013-04-01

Full Text Available This paper focuses on the modelling and control problems of a self-propelled, multimodal amphibious robot. Inspired by the undulatory body motions of fish and dolphins, the amphibious robot propels itself underwater by oscillations of several modular fish-like propelling units coupled with a pair of pectoral fins capable of non-continuous 360 degree rotation. In order to mimic fish-like undulating propulsion, a control architecture based on Central Pattern Generator (CPG is applied to the amphibious robot for robust swimming gaits, including forward and backward swimming and turning, etc. With the simplification of the robot as a multi-link serial mechanism, a Lagrangian function is employed to establish the hydrodynamic model for steady swimming. The CPG motion control law is then imported into the Lagrangian-based dynamic model, where an associated system of kinematics and dynamics is formed to solve real-time movements and, further, to guide the exploration of the CPG parameters and steady locomotion gaits. Finally, comparative results between the simulations and experiments are provided to show the effectiveness of the built control models.

The Effects of Varying Ankle Foot Orthosis Stiffness on Gait in Children with Spastic Cerebral Palsy Who Walk with Excessive Knee Flexion.

Science.gov (United States)

Kerkum, Yvette L; Buizer, Annemieke I; van den Noort, Josien C; Becher, Jules G; Harlaar, Jaap; Brehm, Merel-Anne

2015-01-01

Rigid Ankle-Foot Orthoses (AFOs) are commonly prescribed to counteract excessive knee flexion during the stance phase of gait in children with cerebral palsy (CP). While rigid AFOs may normalize knee kinematics and kinetics effectively, it has the disadvantage of impeding push-off power. A spring-like AFO may enhance push-off power, which may come at the cost of reducing the knee flexion less effectively. Optimizing this trade-off between enhancing push-off power and normalizing knee flexion in stance is expected to maximize gait efficiency. This study investigated the effects of varying AFO stiffness on gait biomechanics and efficiency in children with CP who walk with excessive knee flexion in stance. Fifteen children with spastic CP (11 boys, 10±2 years) were prescribed with a ventral shell spring-hinged AFO (vAFO). The hinge was set into a rigid, or spring-like setting, using both a stiff and flexible performance. At baseline (i.e. shoes-only) and for each vAFO, a 3D-gait analysis and 6-minute walk test with breath-gas analysis were performed at comfortable speed. Lower limb joint kinematics and kinetics were calculated. From the 6-minute walk test, walking speed and the net energy cost were determined. A generalized estimation equation (ppush-off power did not lead to greater reductions in walking energy cost. These findings suggest that, in this specific group of children with spastic CP, the vAFO stiffness that maximizes gait efficiency is primarily determined by its effect on knee kinematics and kinetics rather than by its effect on push-off power. Dutch Trial Register NTR3418.

Modification of hemiplegic compensatory gait pattern by symmetry-based motion controller of HAL.

Science.gov (United States)

Kawamoto, Hiroaki; Kadone, Hideki; Sakurai, Takeru; Sankai, Yoshiyuki

2015-01-01

As one of several characteristics of hemiplegic patients after stroke, compensatory gait caused by affected limb is often seen. The purpose of this research is to apply a symmetry-based controller of a wearable type lower limb robot, Hybrid Assistive Limb (HAL) to hemiplegic patients with compensatory gait, and to investigate improvement of gait symmetry. The controller is designed respectively for swing phase and support phase according to characteristics of hemiplegic gait pattern. The controller during swing phase stores the motion of the unaffected limb and then provides motion support on the affected limb during the subsequent swing using the stored pattern to realize symmetric gait based on spontaneous limb swing. Moreover, the controller during support phase provides motion to extend hip and knee joints to support wearer's body. Clinical tests were conducted in order to assess the modification of gait symmetry. Our case study involved participation of one chronic stroke patient who performs abnormally-compensatory gait for both of the affected and unaffected limbs. As a result, the patient's gait symmetry was improved by providing motion support during the swing phase on the affected side and motion constraint during the support phase on the unaffected side. The study showed promising basis for the effectiveness of the controller for the future clinical study.

A muscle-driven approach to restore stepping with an exoskeleton for individuals with paraplegia.

Science.gov (United States)

Chang, Sarah R; Nandor, Mark J; Li, Lu; Kobetic, Rudi; Foglyano, Kevin M; Schnellenberger, John R; Audu, Musa L; Pinault, Gilles; Quinn, Roger D; Triolo, Ronald J

2017-05-30

Functional neuromuscular stimulation, lower limb orthosis, powered lower limb exoskeleton, and hybrid neuroprosthesis (HNP) technologies can restore stepping in individuals with paraplegia due to spinal cord injury (SCI). However, a self-contained muscle-driven controllable exoskeleton approach based on an implanted neural stimulator to restore walking has not been previously demonstrated, which could potentially result in system use outside the laboratory and viable for long term use or clinical testing. In this work, we designed and evaluated an untethered muscle-driven controllable exoskeleton to restore stepping in three individuals with paralysis from SCI. The self-contained HNP combined neural stimulation to activate the paralyzed muscles and generate joint torques for limb movements with a controllable lower limb exoskeleton to stabilize and support the user. An onboard controller processed exoskeleton sensor signals, determined appropriate exoskeletal constraints and stimulation commands for a finite state machine (FSM), and transmitted data over Bluetooth to an off-board computer for real-time monitoring and data recording. The FSM coordinated stimulation and exoskeletal constraints to enable functions, selected with a wireless finger switch user interface, for standing up, standing, stepping, or sitting down. In the stepping function, the FSM used a sensor-based gait event detector to determine transitions between gait phases of double stance, early swing, late swing, and weight acceptance. The HNP restored stepping in three individuals with motor complete paralysis due to SCI. The controller appropriately coordinated stimulation and exoskeletal constraints using the sensor-based FSM for subjects with different stimulation systems. The average range of motion at hip and knee joints during walking were 8.5°-20.8° and 14.0°-43.6°, respectively. Walking speeds varied from 0.03 to 0.06 m/s, and cadences from 10 to 20 steps/min. A self-contained muscle-driven

Task-driven orbit design and implementation on a robotic C-arm system for cone-beam CT

Science.gov (United States)

Ouadah, S.; Jacobson, M.; Stayman, J. W.; Ehtiati, T.; Weiss, C.; Siewerdsen, J. H.

2017-03-01

Purpose: This work applies task-driven optimization to the design of non-circular orbits that maximize imaging performance for a particular imaging task. First implementation of task-driven imaging on a clinical robotic C-arm system is demonstrated, and a framework for orbit calculation is described and evaluated. Methods: We implemented a task-driven imaging framework to optimize orbit parameters that maximize detectability index d'. This framework utilizes a specified Fourier domain task function and an analytical model for system spatial resolution and noise. Two experiments were conducted to test the framework. First, a simple task was considered consisting of frequencies lying entirely on the fz-axis (e.g., discrimination of structures oriented parallel to the central axial plane), and a "circle + arc" orbit was incorporated into the framework as a means to improve sampling of these frequencies, and thereby increase task-based detectability. The orbit was implemented on a robotic C-arm (Artis Zeego, Siemens Healthcare). A second task considered visualization of a cochlear implant simulated within a head phantom, with spatial frequency response emphasizing high-frequency content in the (fy, fz) plane of the cochlea. An optimal orbit was computed using the task-driven framework, and the resulting image was compared to that for a circular orbit. Results: For the fz-axis task, the circle + arc orbit was shown to increase d' by a factor of 1.20, with an improvement of 0.71 mm in a 3D edge-spread measurement for edges located far from the central plane and a decrease in streak artifacts compared to a circular orbit. For the cochlear implant task, the resulting orbit favored complementary views of high tilt angles in a 360° orbit, and d' was increased by a factor of 1.83. Conclusions: This work shows that a prospective definition of imaging task can be used to optimize source-detector orbit and improve imaging performance. The method was implemented for execution of

An EMG-driven exoskeleton hand robotic training device on chronic stroke subjects: task training system for stroke rehabilitation.

Science.gov (United States)

Ho, N S K; Tong, K Y; Hu, X L; Fung, K L; Wei, X J; Rong, W; Susanto, E A

2011-01-01

An exoskeleton hand robotic training device is specially designed for persons after stroke to provide training on their impaired hand by using an exoskeleton robotic hand which is actively driven by their own muscle signals. It detects the stroke person's intention using his/her surface electromyography (EMG) signals from the hemiplegic side and assists in hand opening or hand closing functional tasks. The robotic system is made up of an embedded controller and a robotic hand module which can be adjusted to fit for different finger length. Eight chronic stroke subjects had been recruited to evaluate the effects of this device. The preliminary results showed significant improvement in hand functions (ARAT) and upper limb functions (FMA) after 20 sessions of robot-assisted hand functions task training. With the use of this light and portable robotic device, stroke patients can now practice more easily for the opening and closing of their hands at their own will, and handle functional daily living tasks at ease. A video is included together with this paper to give a demonstration of the hand robotic system on chronic stroke subjects and it will be presented in the conference. © 2011 IEEE

Invariant hip moment pattern while walking with a robotic hip exoskeleton.

Science.gov (United States)

Lewis, Cara L; Ferris, Daniel P

2011-03-15

Robotic lower limb exoskeletons hold significant potential for gait assistance and rehabilitation; however, we have a limited understanding of how people adapt to walking with robotic devices. The purpose of this study was to test the hypothesis that people reduce net muscle moments about their joints when robotic assistance is provided. This reduction in muscle moment results in a total joint moment (muscle plus exoskeleton) that is the same as the moment without the robotic assistance despite potential differences in joint angles. To test this hypothesis, eight healthy subjects trained with the robotic hip exoskeleton while walking on a force-measuring treadmill. The exoskeleton provided hip flexion assistance from approximately 33% to 53% of the gait cycle. We calculated the root mean squared difference (RMSD) between the average of data from the last 15 min of the powered condition and the unpowered condition. After completing three 30-min training sessions, the hip exoskeleton provided 27% of the total peak hip flexion moment during gait. Despite this substantial contribution from the exoskeleton, subjects walked with a total hip moment pattern (muscle plus exoskeleton) that was almost identical and more similar to the unpowered condition than the hip angle pattern (hip moment RMSD 0.027, angle RMSD 0.134, p<0.001). The angle and moment RMSD were not different for the knee and ankle joints. These findings support the concept that people adopt walking patterns with similar joint moment patterns despite differences in hip joint angles for a given walking speed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Three dimensional design, simulation and optimization of a novel, universal diabetic foot offloading orthosis

Science.gov (United States)

Sukumar, Chand; Ramachandran, K. I.

2016-09-01

Leg amputation is a major consequence of aggregated foot ulceration in diabetic patients. A common sense based treatment approach for diabetic foot ulceration is foot offloading where the patient is required to wear a foot offloading orthosis during the entire treatment course. Removable walker is an excellent foot offloading modality compared to the golden standard solution - total contact cast and felt padding. Commercially available foot offloaders are generally customized with huge cost and less patient compliance. This work suggests an optimized 3D model of a new type light weight removable foot offloading orthosis for diabetic patients. The device has simple adjustable features which make this suitable for wide range of patients with weight of 35 to 74 kg and height of 137 to 180 cm. Foot plate of this orthosis is unisexual, with a size adjustability of (US size) 6 to 10. Materials like Aluminum alloy 6061-T6, Acrylonitrile Butadiene Styrene (ABS) and Polyurethane acted as the key player in reducing weight of the device to 0.804 kg. Static analysis of this device indicated that maximum stress developed in this device under a load of 1000 N is only 37.8 MPa, with a small deflection of 0.150 cm and factor of safety of 3.28, keeping the safety limits, whereas dynamic analysis results assures the load bearing capacity of this device. Thus, the proposed device can be safely used as an orthosis for offloading diabetic ulcerated foot.

Training with a balance exercise assist robot is more effective than conventional training for frail older adults.

Science.gov (United States)

Ozaki, Kenichi; Kondo, Izumi; Hirano, Satoshi; Kagaya, Hitoshi; Saitoh, Eiichi; Osawa, Aiko; Fujinori, Yoichi

2017-11-01

To examine the efficacy of postural strategy training using a balance exercise assist robot (BEAR) as compared with conventional balance training for frail older adults. The present study was designed as a cross-over trial without a washout term. A total of 27 community-dwelling frail or prefrail elderly residents (7 men, 20 women; age range 65-85 years) were selected from a volunteer sample. Two exercises were prepared for interventions: robotic exercise moving the center of gravity by the balance exercise assist robot system; and conventional balance training combining muscle-strengthening exercise, postural strategy training and applied motion exercise. Each exercise was carried out twice a week for 6 weeks. Participants were allocated randomly to either the robotic exercise first group or the conventional balance exercise first group. preferred and maximal gait speeds, tandem gait speeds, timed up-and-go test, functional reach test, functional base of support, center of pressure, and muscle strength of the lower extremities were assessed before and after completion of each exercise program. Robotic exercise achieved significant improvements for tandem gait speed (P = 0.012), functional reach test (P = 0.002), timed up-and-go test (P = 0.023) and muscle strength of the lower extremities (P = 0.001-0.030) compared with conventional exercise. In frail or prefrail older adults, robotic exercise was more effective for improving dynamic balance and lower extremity muscle strength than conventional exercise. These findings suggest that postural strategy training with the balance exercise assist robot is effective to improve the gait instability and muscle weakness often seen in frail older adults. Geriatr Gerontol Int 2017; 17: 1982-1990. © 2017 The Authors. Geriatrics & Gerontology International published by John Wiley & Sons Australia, Ltd on behalf of Japan Geriatrics Society.

Planning strategies for the Ambler walking robot

Science.gov (United States)

Wettergreen, David; Thomas, Hans; Thorpe, Chuck

1990-01-01

A hierarchy of planning strategies is proposed and explained for a walking robot called the Ambler. The hierarchy decomposes planning into levels of trajectory, gait, and footfall. An abstraction of feasible traversability allows the Ambler's trajectory planner to identify acceptable trajectories by finding paths that guarantee footfalls without specifying exactly which footfalls. Leg and body moves that achieve this trajectory can be generated by the Ambler's gait planner, which incorporates pattern constraints and measures of utility to search for the best next move. By combining constraints from the quality and details of the terrain, the Ambler's footfall planner can select footfalls that insure stability and remain within the tolerances of the gait.

Mechanical design and optimal control of humanoid robot (TPinokio

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Teck Chew Wee

2014-04-01

Full Text Available The mechanical structure and the control of the locomotion of bipedal humanoid is an important and challenging domain of research in bipedal robots. Accurate models of the kinematics and dynamics of the robot are essential to achieve bipedal locomotion. Toe-foot walking produces a more natural and faster walking speed and it is even possible to perform stretch knee walking. This study presents the mechanical design of a toe-feet bipedal, TPinokio and the implementation of some optimal walking gait generation methods. The optimality in the gait trajectory is achieved by applying augmented model predictive control method and the pole-zero cancellation method, taken into consideration of a trade-off between walking speed and stability. The mechanism of the TPinokio robot is designed in modular form, so that its kinematics can be modelled accurately into a multiple point-mass system, its dynamics is modelled using the single and double mass inverted pendulum model and zero-moment-point concept. The effectiveness of the design and control technique is validated by simulation testing with the robot walking on flat surface and climbing stairs.

Design of a 3D printed lightweight orthotic device based on twisted and coiled polymer muscle: iGrab hand orthosis

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Saharan, Lokesh; Sharma, Ashvath; Jung de Andrade, Monica; Baughman, Ray H.; Tadesse, Yonas

2017-04-01

Partial or total upper extremity impairment affects the quality of life of a vast number of people due to stroke, neuromuscular disease, or trauma. Many researchers have presented hand orthosis to address the needs of rehabilitation or assistance on upper extremity function. Most of the devices available commercially and in literature are powered by conventional actuators such as DC motors, servomotors or pneumatic actuators. Some prototypes are developed based on shape memory alloy (SMA) and dielectric elastomers (DE). This study presents a customizable, 3D printed, a lightweight exoskeleton (iGrab) based on recently reported Twisted and Coiled Polymer (TCP) muscles, which are lightweight, provide high power to weight ratio and large stroke. We used silver coated nylon 6, 6 threads to make the TCP muscles, which can be easily actuated electrothermally. We reviewed briefly hand orthosis created with various actuation technologies and present our design of tendon-driven exoskeleton with the muscles confined in the forearm area. A single muscle is used to facilitate the motion of all three joints namely DIP (Distal interphalangeal), PIP (Proximal Interphalangeal) and MCP (Metacarpophalangeal) using passive tendons though circular rings. The grasping capabilities, along with TCP muscle properties utilized in the design such as life cycle, actuation under load and power inputs are discussed.

A CORBA-Based Control Architecture for Real-Time Teleoperation Tasks in a Developmental Humanoid Robot

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Hanafiah Yussof

2011-06-01

Full Text Available This paper presents the development of new Humanoid Robot Control Architecture (HRCA platform based on Common Object Request Broker Architecture (CORBA in a developmental biped humanoid robot for real-time teleoperation tasks. The objective is to make the control platform open for collaborative teleoperation research in humanoid robotics via the internet. Meanwhile, to generate optimal trajectory generation in bipedal walk, we proposed a real time generation of optimal gait by using Genetic Algorithms (GA to minimize the energy for humanoid robot gait. In addition, we proposed simplification of kinematical solutions to generate controlled trajectories of humanoid robot legs in teleoperation tasks. The proposed control systems and strategies was evaluated in teleoperation experiments between Australia and Japan using humanoid robot Bonten-Maru. Additionally, we have developed a user-friendly Virtual Reality (VR user interface that is composed of ultrasonic 3D mouse system and a Head Mounted Display (HMD for working coexistence of human and humanoid robot in teleoperation tasks. The teleoperation experiments show good performance of the proposed system and control, and also verified the good performance for working coexistence of human and humanoid robot.

A CORBA-Based Control Architecture for Real-Time Teleoperation Tasks in a Developmental Humanoid Robot

Directory of Open Access Journals (Sweden)

Hanafiah Yussof

2011-06-01

Full Text Available This paper presents the development of new Humanoid Robot Control Architecture (HRCA platform based on Common Object Request Broker Architecture (CORBA in a developmental biped humanoid robot for real‐time teleoperation tasks. The objective is to make the control platform open for collaborative teleoperation research in humanoid robotics via the internet. Meanwhile, to generate optimal trajectory generation in bipedal walk, we proposed a real time generation of optimal gait by using Genetic Algorithms (GA to minimize the energy for humanoid robot gait. In addition, we proposed simplification of kinematical solutions to generate controlled trajectories of humanoid robot legs in teleoperation tasks. The proposed control systems and strategies was evaluated in teleoperation experiments between Australia and Japan using humanoid robot Bonten‐Maru. Additionally, we have developed a user‐ friendly Virtual Reality (VR user interface that is composed of ultrasonic 3D mouse system and a Head Mounted Display (HMD for working coexistence of human and humanoid robot in teleoperation tasks. The teleoperation experiments show good performance of the proposed system and control, and also verified the good performance for working coexistence of human and humanoid robot.

Management of a patient's gait abnormality using smartphone technology in-clinic for improved qualitative analysis: A case report.

Science.gov (United States)

VanWye, William R; Hoover, Donald L

2018-05-01

Qualitative analysis has its limitations as the speed of human movement often occurs more quickly than can be comprehended. Digital video allows for frame-by-frame analysis, and therefore likely more effective interventions for gait dysfunction. Although the use of digital video outside laboratory settings, just a decade ago, was challenging due to cost and time constraints, rapid use of smartphones and software applications has made this technology much more practical for clinical usage. A 35-year-old man presented for evaluation with the chief complaint of knee pain 24 months status-post triple arthrodesis following a work-related crush injury. In-clinic qualitative gait analysis revealed gait dysfunction, which was augmented by using a standard IPhone® 3GS camera. After video capture, an IPhone® application (Speed Up TV®, https://itunes.apple.com/us/app/speeduptv/id386986953?mt=8 ) allowed for frame-by-frame analysis. Corrective techniques were employed using in-clinic equipment to develop and apply a temporary heel-to-toe rocker sole (HTRS) to the patient's shoe. Post-intervention video revealed significantly improved gait efficiency with a decrease in pain. The patient was promptly fitted with a permanent HTRS orthosis. This intervention enabled the patient to successfully complete a work conditioning program and progress to job retraining. Video allows for multiple views, which can be further enhanced by using applications for frame-by-frame analysis and zoom capabilities. This is especially useful for less experienced observers of human motion, as well as for establishing comparative signs prior to implementation of training and/or permanent devices.

The Effects of Upper-Limb Training Assisted with an Electromyography-Driven Neuromuscular Electrical Stimulation Robotic Hand on Chronic Stroke

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Chingyi Nam

2017-12-01

Full Text Available BackgroundImpaired hand dexterity is a major disability of the upper limb after stroke. An electromyography (EMG-driven neuromuscular electrical stimulation (NMES robotic hand was designed previously, whereas its rehabilitation effects were not investigated.ObjectivesThis study aims to investigate the rehabilitation effectiveness of the EMG-driven NMES-robotic hand-assisted upper-limb training on persons with chronic stroke.MethodA clinical trial with single-group design was conducted on chronic stroke participants (n = 15 who received 20 sessions of EMG-driven NMES-robotic hand-assisted upper-limb training. The training effects were evaluated by pretraining, posttraining, and 3-month follow-up assessments with the clinical scores of the Fugl-Meyer Assessment (FMA, the Action Research Arm Test (ARAT, the Wolf Motor Function Test, the Motor Functional Independence Measure, and the Modified Ashworth Scale (MAS. Improvements in the muscle coordination across the sessions were investigated by EMG parameters, including EMG activation level and Co-contraction Indexes (CIs of the target muscles in the upper limb.ResultsSignificant improvements in the FMA shoulder/elbow and wrist/hand scores (P < 0.05, the ARAT (P < 0.05, and in the MAS (P < 0.05 were observed after the training and sustained 3 months later. The EMG parameters indicated a significant decrease of the muscle activation level in flexor digitorum (FD and biceps brachii (P < 0.05, as well as a significant reduction of CIs in the muscle pairs of FD and triceps brachii and biceps brachii and triceps brachii (P < 0.05.ConclusionThe upper-limb training integrated with the assistance from the EMG-driven NMES-robotic hand is effective for the improvements of the voluntary motor functions and the muscle coordination in the proximal and distal joints. Furthermore, the motor improvement after the training could be maintained till 3 months later.Trial registration

The Effects of Upper-Limb Training Assisted with an Electromyography-Driven Neuromuscular Electrical Stimulation Robotic Hand on Chronic Stroke.

Science.gov (United States)

Nam, Chingyi; Rong, Wei; Li, Waiming; Xie, Yunong; Hu, Xiaoling; Zheng, Yongping

2017-01-01

Impaired hand dexterity is a major disability of the upper limb after stroke. An electromyography (EMG)-driven neuromuscular electrical stimulation (NMES) robotic hand was designed previously, whereas its rehabilitation effects were not investigated. This study aims to investigate the rehabilitation effectiveness of the EMG-driven NMES-robotic hand-assisted upper-limb training on persons with chronic stroke. A clinical trial with single-group design was conducted on chronic stroke participants ( n  = 15) who received 20 sessions of EMG-driven NMES-robotic hand-assisted upper-limb training. The training effects were evaluated by pretraining, posttraining, and 3-month follow-up assessments with the clinical scores of the Fugl-Meyer Assessment (FMA), the Action Research Arm Test (ARAT), the Wolf Motor Function Test, the Motor Functional Independence Measure, and the Modified Ashworth Scale (MAS). Improvements in the muscle coordination across the sessions were investigated by EMG parameters, including EMG activation level and Co-contraction Indexes (CIs) of the target muscles in the upper limb. Significant improvements in the FMA shoulder/elbow and wrist/hand scores ( P  < 0.05), the ARAT ( P  < 0.05), and in the MAS ( P  < 0.05) were observed after the training and sustained 3 months later. The EMG parameters indicated a significant decrease of the muscle activation level in flexor digitorum (FD) and biceps brachii ( P  < 0.05), as well as a significant reduction of CIs in the muscle pairs of FD and triceps brachii and biceps brachii and triceps brachii ( P  < 0.05). The upper-limb training integrated with the assistance from the EMG-driven NMES-robotic hand is effective for the improvements of the voluntary motor functions and the muscle coordination in the proximal and distal joints. Furthermore, the motor improvement after the training could be maintained till 3 months later. ClinicalTrials.gov. NCT02117089; date of registration: April

Ankle-Foot Orthosis Made by 3D Printing Technique and Automated Design Software

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Yong Ho Cha

2017-01-01

Full Text Available We described 3D printing technique and automated design software and clinical results after the application of this AFO to a patient with a foot drop. After acquiring a 3D modelling file of a patient’s lower leg with peroneal neuropathy by a 3D scanner, we loaded this file on the automated orthosis software and created the “STL” file. The designed AFO was printed using a fused filament fabrication type 3D printer, and a mechanical stress test was performed. The patient alternated between the 3D-printed and conventional AFOs for 2 months. There was no crack or damage, and the shape and stiffness of the AFO did not change after the durability test. The gait speed increased after wearing the conventional AFO (56.5 cm/sec and 3D-printed AFO (56.5 cm/sec compared to that without an AFO (42.2 cm/sec. The patient was more satisfied with the 3D-printed AFO than the conventional AFO in terms of the weight and ease of use. The 3D-printed AFO exhibited similar functionality as the conventional AFO and considerably satisfied the patient in terms of the weight and ease of use. We suggest the possibility of the individualized AFO with 3D printing techniques and automated design software.

Immediate effect of a functional wrist orthosis for children with cerebral palsy or brain injury: A randomized controlled trial.

Science.gov (United States)

Jackman, Michelle; Novak, Iona; Lannin, Natasha; Galea, Claire

2017-10-28

Two-group randomized controlled trial. Upper limb orthoses worn during functional tasks are commonly used in pediatric neurologic rehabilitation, despite a paucity of high-level evidence. The purpose of this study was to investigate if a customized functional wrist orthosis, when placed on the limb, leads to an immediate improvement in hand function for children with cerebral palsy or brain injury. A 2-group randomized controlled trial involving 30 children was conducted. Participants were randomized to either receive a customized functional wrist orthosis (experimental, n = 15) or not receive an orthosis (control, n = 15). The box and blocks test was administered at baseline and repeated 1 hour after experimental intervention, with the orthosis on if randomized to the orthotic group. After intervention, there were no significant differences on the box and blocks test between the orthotic group (mean, 10.13; standard deviation, 11.476) and the no orthotic group (mean, 14.07; standard deviation, 11.106; t[28], -0.954; P = .348; and 95% confidence interval, -12.380 to 4.513). In contrast to the findings of previous studies, our results suggest that a functional wrist orthosis, when supporting the joint in a 'typical' position, may not lead to an immediate improvement in hand function. Wearing a functional wrist orthosis did not lead to an immediate improvement in the ability of children with cerebral palsy or brain injury to grasp and release. Further research is needed combining upper limb orthoses with task-specific training and measuring outcomes over the medium to long term. Copyright © 2017 Hanley & Belfus. All rights reserved.

Animal and robot experiments to discover principles behind the evolution of a minimal locomotor apparatus for robust legged locomotion

Science.gov (United States)

McInroe, Benjamin; Astley, Henry; Kawano, Sandy; Blob, Richard; Goldman, Daniel I.

2015-03-01

In the evolutionary transition from an aquatic to a terrestrial environment, early walkers adapted to the challenges of locomotion on complex, flowable substrates (e.g. sand and mud). Our previous biological and robotic studies have demonstrated that locomotion on such substrates is sensitive to both limb morphology and kinematics. Although reconstructions of early vertebrate skeletal morphologies exist, the kinematic strategies required for successful locomotion by these organisms have not yet been explored. To gain insight into how early walkers contended with complex substrates, we developed a robotic model with appendage morphology inspired by a model analog organism, the mudskipper. We tested mudskippers and the robot on different substrates, including rigid ground and dry granular media, varying incline angle. The mudskippers moved effectively on all level substrates using a fin-driven gait. But as incline angle increased, the animals used their tails in concert with their fins to generate propulsion. Adding an actuated tail to the robot improved robustness, making possible locomotion on otherwise inaccessible inclines. With these discoveries, we are elucidating a minimal template that may have allowed the early walkers to adapt to locomotion on land. This work was supported by NSF PoLS.

Improving the transparency of a rehabilitation robot by exploiting the cyclic behaviour of walking.

Science.gov (United States)

van Dijk, W; van der Kooij, H; Koopman, B; van Asseldonk, E H F; van der Kooij, H

2013-06-01

To promote active participation of neurological patients during robotic gait training, controllers, such as "assist as needed" or "cooperative control", are suggested. Apart from providing support, these controllers also require that the robot should be capable of resembling natural, unsupported, walking. This means that they should have a transparent mode, where the interaction forces between the human and the robot are minimal. Traditional feedback-control algorithms do not exploit the cyclic nature of walking to improve the transparency of the robot. The purpose of this study was to improve the transparent mode of robotic devices, by developing two controllers that use the rhythmic behavior of gait. Both controllers use adaptive frequency oscillators and kernel-based non-linear filters. Kernelbased non-linear filters can be used to estimate signals and their time derivatives, as a function of the gait phase. The first controller learns the motor angle, associated with a certain joint angle pattern, and acts as a feed-forward controller to improve the torque tracking (including the zero-torque mode). The second controller learns the state of the mechanical system and compensates for the dynamical effects (e.g. the acceleration of robot masses). Both controllers have been tested separately and in combination on a small subject population. Using the feedforward controller resulted in an improved torque tracking of at least 52 percent at the hip joint, and 61 percent at the knee joint. When both controllers were active simultaneously, the interaction power between the robot and the human leg was reduced by at least 40 percent at the thigh, and 43 percent at the shank. These results indicate that: if a robotic task is cyclic, the torque tracking and transparency can be improved by exploiting the predictions of adaptive frequency oscillator and kernel-based nonlinear filters.

Investigating the feasibility of a BCI-driven robot-based writing agent for handicapped individuals

Science.gov (United States)

Syan, Chanan S.; Harnarinesingh, Randy E. S.; Beharry, Rishi

2014-07-01

Brain-Computer Interfaces (BCIs) predominantly employ output actuators such as virtual keyboards and wheelchair controllers to enable handicapped individuals to interact and communicate with their environment. However, BCI-based assistive technologies are limited in their application. There is minimal research geared towards granting disabled individuals the ability to communicate using written words. This is a drawback because involving a human attendant in writing tasks can entail a breach of personal privacy where the task entails sensitive and private information such as banking matters. BCI-driven robot-based writing however can provide a safeguard for user privacy where it is required. This study investigated the feasibility of a BCI-driven writing agent using the 3 degree-of- freedom Phantom Omnibot. A full alphanumerical English character set was developed and validated using a teach pendant program in MATLAB. The Omnibot was subsequently interfaced to a P300-based BCI. Three subjects utilised the BCI in the online context to communicate words to the writing robot over a Local Area Network (LAN). The average online letter-wise classification accuracy was 91.43%. The writing agent legibly constructed the communicated letters with minor errors in trajectory execution. The developed system therefore provided a feasible platform for BCI-based writing.

Investigating the feasibility of a BCI-driven robot-based writing agent for handicapped individuals

International Nuclear Information System (INIS)

Syan, Chanan S; Harnarinesingh, Randy E S; Beharry, Rishi

2014-01-01

Brain-Computer Interfaces (BCIs) predominantly employ output actuators such as virtual keyboards and wheelchair controllers to enable handicapped individuals to interact and communicate with their environment. However, BCI-based assistive technologies are limited in their application. There is minimal research geared towards granting disabled individuals the ability to communicate using written words. This is a drawback because involving a human attendant in writing tasks can entail a breach of personal privacy where the task entails sensitive and private information such as banking matters. BCI-driven robot-based writing however can provide a safeguard for user privacy where it is required. This study investigated the feasibility of a BCI-driven writing agent using the 3 degree-of- freedom Phantom Omnibot. A full alphanumerical English character set was developed and validated using a teach pendant program in MATLAB. The Omnibot was subsequently interfaced to a P300-based BCI. Three subjects utilised the BCI in the online context to communicate words to the writing robot over a Local Area Network (LAN). The average online letter-wise classification accuracy was 91.43%. The writing agent legibly constructed the communicated letters with minor errors in trajectory execution. The developed system therefore provided a feasible platform for BCI-based writing

Next Generation Light Robotics

DEFF Research Database (Denmark)

Glückstad, Jesper

Light Robotics is a new field of research where ingredients from photonics, nanotechnology and biotechnology are put together in new ways to realize light-driven robotics at the smallest scales to solve major challenges primarily within the nanobio-domain but not limited hereto. Exploring the full...... potential of this new ‘drone-like’ light-printed, light-driven, light-actuated micro- and nano-robotics in challenging geometries requires a versatile and real-time reconfigurable light addressing that can dynamically track a plurality of tiny tools in 3D to ensure real-time continuous light...

Can an ankle-foot orthosis change hearts and minds?

Science.gov (United States)

Patzkowski, Jeanne C; Blanck, Ryan V; Owens, Johnny G; Wilken, Jason M; Blair, James A; Hsu, Joseph R

2011-01-01

The current military conflicts of Operation Enduring Freedom and Operation Iraqi Freedom have been characterized by high-energy explosive wounding patterns, with the majority affecting the extremities. While many injuries have resulted in amputation, surgical advances have allowed the orthopaedic surgeon to pursue limb salvage in the face of injuries once considered unsalvageable. The military limb salvage patient is frequently highly active and motivated and expresses significant frustration with the slow nature of limb salvage rehabilitation and continued functional deficits. Inspired by these patients, efforts at this institution began to provide them with a more dynamic orthosis. Utilizing techniques and technology resulting from cerebral palsy, stroke, and amputation research, the Intrepid Dynamic Exoskeletal Orthosis was created. To date, this device has significantly improved the functional capabilities of the limb salvage wounded warrior population when combined with a high-intensity rehabilitation program. Clinical and biomechanical research is currently underway at this institution in order to fully characterize the device, its effect on patients, and what can be done to modify future generations of the device to best serve the combat-wounded limb salvage population.

An Open-Structure Treadmill Gait Trainer: From Research to Application

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Jian Li

2017-01-01

Full Text Available Lower limb rehabilitation robots are designed to enhance gait function in individuals with motor impairments. Although numerous rehabilitation robots have been developed, only few of these robots have been used in practical health care, particularly in China. The objective of this study is to construct a lower limb rehabilitation robot and bridge the gap between research and application. Open structure to facilitate practical application was created for the whole robot. Three typical movement patterns of a single leg were adopted in designing the exoskeletons, and force models for patient training were established and analyzed under three different conditions, respectively, and then a control system and security strategy were introduced. After establishing the robot, a preliminary experiment on the actual use of a prototype by patients was conducted to validate the functionality of the robot. The experiment showed that different patients and stages displayed different performances, and results on the trend variations across patients and across stages confirmed the validity of the robot and suggested that the design may lead to a system that could be successful in the treatment of patients with walking disorders in China. Furthermore, this study could provide a reference for a similar application design.

Initial experience using a robotic-driven laparoscopic needle holder with ergonomic handle: assessment of surgeons' task performance and ergonomics.

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Sánchez-Margallo, Juan A; Sánchez-Margallo, Francisco M

2017-12-01

The objective of this study is to assess the surgeons' performance and ergonomics during the use of a robotic-driven needle holder in laparoscopic suturing tasks. Six right-handed laparoscopic surgeons with different levels of experience took part in this study. Participants performed a set of three different intracorporeal suturing tasks organized in ten trials during a period of five weeks. Surgeons used both conventional (Conv) and robotic (Rob) laparoscopic needle holders. Precision using the surgical needle, quality of the intracorporeal suturing performance, execution time and leakage pressure for the urethrovesical anastomosis, as well as the ergonomics of the surgeon's hand posture, were analyzed during the first, fifth and last trials. No statistically significant differences in precision and quality of suturing performance were obtained between both groups of instruments. Surgeons required more time using the robotic instrument than using the conventional needle holder to perform the urethrovesical anastomosis, but execution time was significantly reduced after training ([Formula: see text] 0.05). There were no differences in leakage pressure for the anastomoses carried out by both instruments. After training, novice surgeons significantly improved the ergonomics of the wrist ([Formula: see text] 0.05) and index finger (Conv: 36.381[Formula: see text], Rob: 30.389[Formula: see text]; p = 0.024) when using the robotic instrument compared to the conventional needle holder. Results have shown that, although both instruments offer similar technical performance, the robotic-driven instrument results in better ergonomics for the surgeon's hand posture compared to the use of a conventional laparoscopic needle holder in intracorporeal suturing.

A Novel Approach For Ankle Foot Orthosis Developed By Three Dimensional Technologies

Science.gov (United States)

Belokar, R. M.; Banga, H. K.; Kumar, R.

2017-12-01

This study presents a novel approach for testing mechanical properties of medical orthosis developed by three dimensional (3D) technologies. A hand-held type 3D laser scanner is used for generating 3D mesh geometry directly from patient’s limb. Subsequently 3D printable orthotic design is produced from crude input model by means of Computer Aided Design (CAD) software. Fused Deposition Modelling (FDM) method in Additive Manufacturing (AM) technologies is used to fabricate the 3D printable Ankle Foot Orthosis (AFO) prototype in order to test the mechanical properties on printout. According to test results, printed Acrylonitrile Butadiene Styrene (ABS) AFO prototype has sufficient elasticity modulus and durability for patient-specific medical device manufactured by the 3D technologies.

Optimum path planning of mobile robot in unknown static and dynamic environments using Fuzzy-Wind Driven Optimization algorithm

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Anish Pandey

2017-02-01

Full Text Available This article introduces a singleton type-1 fuzzy logic system (T1-SFLS controller and Fuzzy-WDO hybrid for the autonomous mobile robot navigation and collision avoidance in an unknown static and dynamic environment. The WDO (Wind Driven Optimization algorithm is used to optimize and tune the input/output membership function parameters of the fuzzy controller. The WDO algorithm is working based on the atmospheric motion of infinitesimal small air parcels navigates over an N-dimensional search domain. The performance of this proposed technique has compared through many computer simulations and real-time experiments by using Khepera-III mobile robot. As compared to the T1-SFLS controller the Fuzzy-WDO algorithm is found good agreement for mobile robot navigation.

Development of Multiple Capsule Robots in Pipe

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Shuxiang Guo

2018-05-01

Full Text Available Swallowable capsule robots which travel in body cavities to implement drug delivery, minimally invasive surgery, and diagnosis have provided great potential for medical applications. However, the space constraints of the internal environment and the size limitations of the robots are great challenges to practical application. To address the fundamental challenges of narrow body cavities, a different-frequency driven approach for multiple capsule robots with screw structure manipulated by external electromagnetic field is proposed in this paper. The multiple capsule robots are composed of driven permanent magnets, joint permanent magnets, and a screw body. The screw body generates a propulsive force in a fluidic environment. Moreover, robots can form new constructions via mutual docking and release. To provide manipulation guidelines for active locomotion, a dynamic model of axial propulsion and circumferential torque is established. The multiple start and step-out frequencies for multiple robots are defined theoretically. Moreover, the different-frequency driven approach based on geometrical parameters of screw structure and the overlap angles of magnetic polarities is proposed to drive multiple robots in an identical electromagnetic field. Finally, two capsule robots were prototyped and experiments in a narrow pipe were conducted to verify the different motions such as docking, release, and cooperative locomotion. The experimental results demonstrated the validity of the driven approach for multiple capsule robots in narrow body cavities.

Morphological self stabilization of locomotion gaits: illustration on a few examples from bio-inspired locomotion

OpenAIRE

Chevallereau , Christine; Boyer , Frédéric; Porez , Mathieu; Mauny , Johan; Aoustin , Yannick

2017-01-01

International audience; — To a large extent, robotics locomotion can be viewed as cyclic motions, named gaits. Due to the high complexity of the locomotion dynamics, to find the control laws that ensure an expected gait and its stability with respect to external perturbations, is a challenging issue for feedback control. To address this issue, a promising way is to take inspiration from animals that intensively exploit the interactions of the passive degrees of freedom of their body with thei...

Approaching human performance the functionality-driven Awiwi robot hand

CERN Document Server

Grebenstein, Markus

2014-01-01

Humanoid robotics have made remarkable progress since the dawn of robotics. So why don't we have humanoid robot assistants in day-to-day life yet? This book analyzes the keys to building a successful humanoid robot for field robotics, where collisions become an unavoidable part of the game. The author argues that the design goal should be real anthropomorphism, as opposed to mere human-like appearance. He deduces three major characteristics to aim for when designing a humanoid robot, particularly robot hands: _ Robustness against impacts _ Fast dynamics _ Human-like grasping and manipulation performance   Instead of blindly copying human anatomy, this book opts for a holistic design me-tho-do-lo-gy. It analyzes human hands and existing robot hands to elucidate the important functionalities that are the building blocks toward these necessary characteristics.They are the keys to designing an anthropomorphic robot hand, as illustrated in the high performance anthropomorphic Awiwi Hand presented in this book.  ...

[The use of a robot-assisted Gait Trainer GT1 in patients in the acute period of cerebral stroke: a pilot study].

Science.gov (United States)

Skvortsova, V I; Ivanova, G E; Kovrazhkina, E A; Rumiantseva, N A; Staritsyn, A N; Suvorov, A Iu; Sogomonian, E K

2008-01-01

An aim of the study was to evaluate efficacy of using Gait Trainer GT1, a robot-assisted gait trainer with a system of body-weight support, for the rehabilitation of gait in patients in the acute period of cerebral stroke. A main group included 30 patients in the acute period of ischemic and hemorrhage stroke and a control group--20 age- and sex matched patients. Patients of both groups had daily kinesitherapy sessions with a rehabilitator. Patients of the main group had additional sessions on the Gait Trainer GT1 from the moment of functional readiness to adequate orthostatic probe. Efficacy of rehabilitation was assessed in the four following phases: the first verticalization of patient in the standing position, adaptation of patient to the standing position, walking with assistance, independent walking. Muscular power (scores) in all muscles of low extremities, muscle tonus (the Ashfort scale), amplitude of tendinous reflexes on the reflexes scale, sensory disturbances and discoordination syndromes (specially elaborated scales), pathological positions in the axial muscular system and extremities, functional status (a steadiness scale, the Berg balance scale, the Barthel scale, 5 m test) were assessed in each phase. Stabilometry was conducted for objective evaluation of vertical balance function. The duration of sessions on GT1 and a number of exercises were depended on the patient's tolerability to physical activity. Percentage of relief was determined by the ability of a patient to balance in the standing position. Each patient had 8-10 sessions. A significant improvement of the functional status: ability to balance in standing position, walking, increase of self-care skills were observed in both groups. No significant differences in the level of functional improvements were found compared to the control group. However some peculiarities of the rehabilitation of primary neurologic deficit were observed during CT1-trainings: the normalization of muscle tonus

Standardized voluntary force measurement in a lower extremity rehabilitation robot

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Bolliger Marc

2008-10-01

Full Text Available Abstract Background Isometric force measurements in the lower extremity are widely used in rehabilitation of subjects with neurological movement disorders (NMD because walking ability has been shown to be related to muscle strength. Therefore muscle strength measurements can be used to monitor and control the effects of training programs. A new method to assess isometric muscle force was implemented in the driven gait orthosis (DGO Lokomat. To evaluate the capabilities of this new measurement method, inter- and intra-rater reliability were assessed. Methods Reliability was assessed in subjects with and without NMD. Subjects were tested twice on the same day by two different therapists to test inter-rater reliability and on two separate days by the same therapist to test intra-rater reliability. Results Results showed fair to good reliability for the new measurement method to assess isometric muscle force of lower extremities. In subjects without NMD, intraclass correlation coefficients (ICC for inter-rater reliability ranged from 0.72 to 0.97 and intra-rater reliability from 0.71 to 0.90. In subjects with NMD, ICC ranged from 0.66 to 0.97 for inter-rater and from 0.50 to 0.96 for intra-rater reliability. Conclusion Inter- and intra- rater reliability of an assessment method for measuring maximal voluntary isometric muscle force of lower extremities was demonstrated. We suggest that this method is a valuable tool for documentation and controlling of the rehabilitation process in patients using a DGO.

Multi-source micro-friction identification for a class of cable-driven robots with passive backbone

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Tjahjowidodo, Tegoeh; Zhu, Ke; Dailey, Wayne; Burdet, Etienne; Campolo, Domenico

2016-12-01

This paper analyses the dynamics of cable-driven robots with a passive backbone and develops techniques for their dynamic identification, which are tested on the H-Man, a planar cabled differential transmission robot for haptic interaction. The mechanism is optimized for human-robot interaction by accounting for the cost-benefit-ratio of the system, specifically by eliminating the necessity of an external force sensor to reduce the overall cost. As a consequence, this requires an effective dynamic model for accurate force feedback applications which include friction behavior in the system. We first consider the significance of friction in both the actuator and backbone spaces. Subsequently, we study the required complexity of the stiction model for the application. Different models representing different levels of complexity are investigated, ranging from the conventional approach of Coulomb to an advanced model which includes hysteresis. The results demonstrate each model's ability to capture the dynamic behavior of the system. In general, it is concluded that there is a trade-off between model accuracy and the model cost.

International Conference on Wearable Sensors and Robots 2015

CERN Document Server

Virk, G; Yang, Huayong

2017-01-01

These proceedings present the latest information on regulations and standards for medical and non-medical devices, including wearable robots for gait training and support, design of exoskeletons for the elderly, innovations in assistive robotics, and analysis of human–machine interactions taking into account ergonomic considerations. The rapid development of key mechatronics technologies in recent years has shown that human living standards have significantly improved, and the International Conference on Wearable Sensor and Robot was held in Hangzhou, China from October 16 to 18, 2015, to present research mainly focused on personal-care robots and medical devices. The aim of the conference was to bring together academics, researchers, engineers and students from across the world to discuss state-of-the-art technologies related to various aspects of wearable sensors and robots. .

Brain-state dependent robotic reaching movement with a multi-joint arm exoskeleton: combining brain-machine interfacing and robotic rehabilitation

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Daniel eBrauchle

2015-10-01

Full Text Available While robot-assisted arm and hand training after stroke allows for intensive task-oriented practice, it has provided only limited additional benefit over dose-matched physiotherapy up to now. These rehabilitation devices are possibly too supportive during the exercises. Neurophysiological signals might be one way of avoiding slacking and providing robotic support only when the brain is particularly responsive to peripheral input.We tested the feasibility of three-dimensional robotic assistance for reach-to-grasp movements with a multi-joint exoskeleton during motor imagery-related desynchronization of sensorimotor oscillations in the β-band only. We also registered task-related network changes of cortical functional connectivity by electroencephalography via the imaginary part of the coherence function.Healthy subjects and stroke survivors showed similar patterns – but different aptitudes – of controlling the robotic movement. All participants in this pilot study with nine healthy subjects and two stroke patients achieved their maximum performance during the early stages of the task. Robotic control was significantly higher and less variable when proprioceptive feedback was provided in addition to visual feedback, i.e. when the orthosis was actually attached to the subject’s arm during the task. A distributed cortical network of task-related coherent activity in the θ-band showed significant differences between healthy subjects and stroke patients as well as between early and late periods of the task.Brain-robot interfaces may successfully link three-dimensional robotic training to the participants’ efforts and allow for task-oriented practice of activities of daily living with a physiologically controlled multi-joint exoskeleton. Changes of cortical physiology during the task might also help to make subject-specific adjustments of task difficulty and guide adjunct interventions to facilitate motor learning for functional restoration.

Task driven optimal leg trajectories in insect-scale legged microrobots

Science.gov (United States)

Doshi, Neel; Goldberg, Benjamin; Jayaram, Kaushik; Wood, Robert

Origami inspired layered manufacturing techniques and 3D-printing have enabled the development of highly articulated legged robots at the insect-scale, including the 1.43g Harvard Ambulatory MicroRobot (HAMR). Research on these platforms has expanded its focus from manufacturing aspects to include design optimization and control for application-driven tasks. Consequently, the choice of gait selection, body morphology, leg trajectory, foot design, etc. have become areas of active research. HAMR has two controlled degrees-of-freedom per leg, making it an ideal candidate for exploring leg trajectory. We will discuss our work towards optimizing HAMR's leg trajectories for two different tasks: climbing using electroadhesives and level ground running (5-10 BL/s). These tasks demonstrate the ability of single platform to adapt to vastly different locomotive scenarios: quasi-static climbing with controlled ground contact, and dynamic running with un-controlled ground contact. We will utilize trajectory optimization methods informed by existing models and experimental studies to determine leg trajectories for each task. We also plan to discuss how task specifications and choice of objective function have contributed to the shape of these optimal leg trajectories.

Invariant ankle moment patterns when walking with and without a robotic ankle exoskeleton.

Science.gov (United States)

Kao, Pei-Chun; Lewis, Cara L; Ferris, Daniel P

2010-01-19

To guide development of robotic lower limb exoskeletons, it is necessary to understand how humans adapt to powered assistance. The purposes of this study were to quantify joint moments while healthy subjects adapted to a robotic ankle exoskeleton and to determine if the period of motor adaptation is dependent on the magnitude of robotic assistance. The pneumatically powered ankle exoskeleton provided plantar flexor torque controlled by the wearer's soleus electromyography (EMG). Eleven naïve individuals completed two 30-min sessions walking on a split-belt instrumented treadmill at 1.25m/s while wearing the ankle exoskeleton. After two sessions of practice, subjects reduced their soleus EMG activation by approximately 36% and walked with total ankle moment patterns similar to their unassisted gait (r(2)=0.98+/-0.02, THSD, p>0.05). They had substantially different ankle kinematic patterns compared to their unassisted gait (r(2)=0.79+/-0.12, THSD, probotic ankle exoskeleton (Gordon and Ferris, 2007). Our results strongly suggest that humans aim for similar joint moment patterns when walking with robotic assistance rather than similar kinematic patterns. In addition, greater robotic assistance provided during initial use results in a longer adaptation process than lesser robotic assistance. Copyright 2009 Elsevier Ltd. All rights reserved.

Nonlinear control methods for planar carangiform robot fish locomotion

OpenAIRE

Morgansen, Kristi A.; Duindam, Vincent; Mason, Richard J.; Burdick, Joel W.; Murray, Richard M.

2001-01-01

Considers the design of motion control algorithms for robot fish. We present modeling, control design, and experimental trajectory tracking results for an experimental planar robotic fish system that is propelled using carangiform-like locomotion. Our model for the fish's propulsion is based on quasi-steady fluid flow. Using this model, we propose gaits for forward and turning trajectories and analyze system response under such control strategies. Our models and predictions are verified by ex...

Early Stroke Rehabilitation of the Upper Limb Assisted with an Electromyography-Driven Neuromuscular Electrical Stimulation-Robotic Arm

Directory of Open Access Journals (Sweden)

Qiuyang Qian

2017-09-01

Full Text Available BackgroundEffective poststroke motor rehabilitation depends on repeated limb practice with voluntary efforts. An electromyography (EMG-driven neuromuscular electrical stimulation (NMES-robot arm was designed for the multi-joint physical training on the elbow, the wrist, and the fingers.ObjectivesTo investigate the training effects of the device-assisted approach on subacute stroke patients and to compare the effects with those achieved by the traditional physical treatments.MethodThis study was a pilot randomized controlled trial with a 3-month follow-up. Subacute stroke participants were randomly assigned into two groups, and then received 20-session upper limb training with the EMG-driven NMES-robotic arm (NMES-robot group, n = 14 or the time-matched traditional therapy (the control, n = 10. For the evaluation of the training effects, clinical assessments including Fugl-Meyer Assessment (FMA, Modified Ashworth Score (MAS, Action Research Arm Test (ARAT, and Function Independence Measurement (FIM were conducted before, after the rehabilitation training, and 3 months later. Session-by-session EMG parameters in the NMES-robot group, including normalized co-contraction Indexes (CI and EMG activation level of target muscles, were used to monitor the progress in muscular coordination patterns.ResultsSignificant improvements were obtained in FMA (full score and shoulder/elbow, ARAT, and FIM [P < 0.001, effect sizes (EFs > 0.279] for both groups. Significant improvement in FMA wrist/hand was only observed in the NMES-robot group (P < 0.001, EFs = 0.435 after the treatments. Significant reduction in MAS wrist was observed in the NMES-robot group after the training (P < 0.05, EFs = 0.145 and the effects were maintained for 3 months. MAS scores in the control group were elevated following training (P < 0.05, EFs > 0.24, and remained at an elevated level when assessed 3 months later. The EMG parameters

Locomotion of inchworm-inspired robot made of smart soft composite (SSC)

International Nuclear Information System (INIS)

Wang, Wei; Lee, Jang-Yeob; Rodrigue, Hugo; Song, Sung-Hyuk; Ahn, Sung-Hoon; Chu, Won-Shik

2014-01-01

A soft-bodied robot made of smart soft composite with inchworm-inspired locomotion capable of both two-way linear and turning movement has been proposed, developed, and tested. The robot was divided into three functional parts based on the different functions of the inchworm: the body, the back foot, and the front foot. Shape memory alloy wires were embedded longitudinally in a soft polymer to imitate the longitudinal muscle fibers that control the abdominal contractions of the inchworm during locomotion. Each foot of the robot has three segments with different friction coefficients to implement the anchor and sliding movement. Then, utilizing actuation patterns between the body and feet based on the looping gait, the robot achieves a biomimetic inchworm gait. Experiments were conducted to evaluate the robot’s locomotive performance for both linear locomotion and turning movement. Results show that the proposed robot’s stride length was nearly one third of its body length, with a maximum linear speed of 3.6 mm s −1 , a linear locomotion efficiency of 96.4%, a maximum turning capability of 4.3 degrees per stride, and a turning locomotion efficiency of 39.7%. (paper)

Estimation of Human Hip and Knee Multi-Joint Dynamics Using the LOPES Gait Trainer

NARCIS (Netherlands)

Koopman, Hubertus F.J.M.; van Asseldonk, Edwin H.F.; van der Kooij, Herman

2016-01-01

In this study, we present and evaluate a novel method to estimate multi-joint leg impedance, using a robotic gait training device. The method is based on multi-input–multi-output system identification techniques and is designed for continuous torque perturbations at the hip and knee joint

Towards an ankle neuroprosthesis for hybrid robotics: Concepts and current sources for functional electrical stimulation.

Science.gov (United States)

Casco, S; Fuster, I; Galeano, R; Moreno, J C; Pons, J L; Brunetti, F

2017-07-01

Hybrid rehabilitation robotics combine neuro-prosthetic devices (close-loop functional electrical stimulation systems) and traditional robotic structures and actuators to explore better therapies and promote a more efficient motor function recovery or compensation. Although hybrid robotics and ankle neuroprostheses (NPs) have been widely developed over the last years, there are just few studies on the use of NPs to electrically control both ankle flexion and extension to promote ankle recovery and improved gait patterns in paretic limbs. The aim of this work is to develop an ankle NP specifically designed to work in the field of hybrid robotics. This article presents early steps towards this goal and makes a brief review about motor NPs and Functional Electrical Stimulation (FES) principles and most common devices used to aid the ankle functioning during the gait cycle. It also shows a current sources analysis done in this framework, in order to choose the best one for this intended application.

The Effects of Varying Ankle Foot Orthosis Stiffness on Gait in Children with Spastic Cerebral Palsy Who Walk with Excessive Knee Flexion.

Directory of Open Access Journals (Sweden)

Yvette L Kerkum

Full Text Available Rigid Ankle-Foot Orthoses (AFOs are commonly prescribed to counteract excessive knee flexion during the stance phase of gait in children with cerebral palsy (CP. While rigid AFOs may normalize knee kinematics and kinetics effectively, it has the disadvantage of impeding push-off power. A spring-like AFO may enhance push-off power, which may come at the cost of reducing the knee flexion less effectively. Optimizing this trade-off between enhancing push-off power and normalizing knee flexion in stance is expected to maximize gait efficiency. This study investigated the effects of varying AFO stiffness on gait biomechanics and efficiency in children with CP who walk with excessive knee flexion in stance. Fifteen children with spastic CP (11 boys, 10±2 years were prescribed with a ventral shell spring-hinged AFO (vAFO. The hinge was set into a rigid, or spring-like setting, using both a stiff and flexible performance. At baseline (i.e. shoes-only and for each vAFO, a 3D-gait analysis and 6-minute walk test with breath-gas analysis were performed at comfortable speed. Lower limb joint kinematics and kinetics were calculated. From the 6-minute walk test, walking speed and the net energy cost were determined. A generalized estimation equation (p<0.05 was used to analyze the effects of different conditions. Compared to shoes-only, all vAFOs improved the knee angle and net moment similarly. Ankle power generation and work were preserved only by the spring-like vAFOs. All vAFOs decreased the net energy cost compared to shoes-only, but no differences were found between vAFOs, showing that the effects of spring-like vAFOs to promote push-off power did not lead to greater reductions in walking energy cost. These findings suggest that, in this specific group of children with spastic CP, the vAFO stiffness that maximizes gait efficiency is primarily determined by its effect on knee kinematics and kinetics rather than by its effect on push-off power

Fault Diagnosis of a Reconfigurable Crawling–Rolling Robot Based on Support Vector Machines

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Karthikeyan Elangovan

2017-10-01

Full Text Available As robots begin to perform jobs autonomously, with minimal or no human intervention, a new challenge arises: robots also need to autonomously detect errors and recover from faults. In this paper, we present a Support Vector Machine (SVM-based fault diagnosis system for a bio-inspired reconfigurable robot named Scorpio. The diagnosis system needs to detect and classify faults while Scorpio uses its crawling and rolling locomotion modes. Specifically, we classify between faulty and non-faulty conditions by analyzing onboard Inertial Measurement Unit (IMU sensor data. The data capture nine different locomotion gaits, which include rolling and crawling modes, at three different speeds. Statistical methods are applied to extract features and to reduce the dimensionality of original IMU sensor data features. These statistical features were given as inputs for training and testing. Additionally, the c-Support Vector Classification (c-SVC and nu-SVC models of SVM, and their fault classification accuracies, were compared. The results show that the proposed SVM approach can be used to autonomously diagnose locomotion gait faults while the reconfigurable robot is in operation.

Feasibility Study of a Socially Assistive Humanoid Robot for Guiding Elderly Individuals during Walking

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Chiara Piezzo

2017-07-01

Full Text Available The impact of the world-wide ageing population has commenced with respect to society in developed countries. Several researchers focused on exploring new methods to improve the quality of life of elderly individuals by allowing them to remain independent and healthy to the maximum possible extent. For example, new walking aids are designed to allow elderly individuals to remain mobile in a safe manner because the importance of walking is well-known. The aim of the present study involves designing a humanoid robot guide as a walking trainer for elderly individuals. It is hypothesized that the same service robot provides an assistive and social contribution with respect to interaction between elderly users by motivating them to walk more and simultaneously provides assistance, such as physical assistance and gait monitoring, while walking. This study includes a detailed statement of the research problem as well as a literature review of existing studies related to walking companion robots. A user-centred design approach is adopted to report the results of the current first feasibility study by using a commercially available humanoid robot known as Pepper developed by Softbank-Aldebaran. A quantitative questionnaire was used to investigate all elements that assess intrinsic motivation in users while performing a given activity. Conversely, basic gait data were acquired through a video analysis to test the capability of the robot to modify the gait of human users. The results in terms of the feedback received from elderly subjects and the literature review improve the design of the walking trainer for elderly individuals.

Light Robotics: Aiming towards all-optical nano-robotics

DEFF Research Database (Denmark)

Glückstad, Jesper; Palima, Darwin; Bañas, Andrew

2017-01-01

potential of this new ‘drone-like’ light-printed, light-driven, light-actuated micro- and nanorobotics in challenging geometries requires a versatile and real-time reconfigurable light addressing that can dynamically track a plurality of tiny tools in 3D to ensure real-time continuous light delivery......Light Robotics is a new field of research where ingredients from photonics, nanotechnology and biotechnology are put together in new ways to realize light-driven robotics at the smallest scales to solve major challenges primarily within the nanobio-domain but not limited hereto. Exploring the full...... on the fly. Our latest developments in this new and exciting research area will be reviewed....

Light robotics: aiming towards all-optical nano-robotics

Science.gov (United States)

Glückstad, Jesper; Palima, Darwin; Banas, Andrew

2017-04-01

Light Robotics is a new field of research where ingredients from photonics, nanotechnology and biotechnology are put together in new ways to realize light-driven robotics at the smallest scales to solve major challenges primarily within the nanobio-domain but not limited hereto. Exploring the full potential of this new `drone-like' light-printed, light-driven, light-actuated micro- and nanorobotics in challenging geometries requires a versatile and real-time reconfigurable light addressing that can dynamically track a plurality of tiny tools in 3D to ensure real-time continuous light-delivery on the fly. Our latest developments in this new and exciting research area will be reviewed.

The quadruped robot adaptive control in trotting gait walking on slopes

Science.gov (United States)

Zhang, Shulong; Ma, Hongxu; Yang, Yu; Wang, Jian

2017-10-01

The quadruped robot can be decomposed into a planar seven-link closed kinematic chain in the direction of supporting line and a linear inverted pendulum in normal direction of supporting line. The ground slope can be estimated by using the body attitude information and supporting legs length. The slope degree is used in feedback, to achieve the point of quadruped robot adaptive control walking on slopes. The simulation results verify that the quadruped robot can achieves steady locomotion on the slope with the control strategy proposed in this passage.

Design and analysis of an original powered foot clearance creator mechanism for walking in patients with spinal cord injury.

Science.gov (United States)

Maleki, Maryam; Badri, Samaneh; Shayestehepour, Hamed; Arazpour, Mokhtar; Farahmand, Farzam; Mousavi, Mohamad Ebrahim; Abdolahi, Ehsan; Farkhondeh, Hasan; Head, John S; Golchin, Navid; Mardani, Mohammad Ali

2018-03-12

The aim of this study was to assess the performance of an original powered foot clearance creator (PFCC) mechanism worn in conjunction with an isocentric reciprocal gait orthosis (IRGO) and evaluate its effect on trunk compensatory movements and spatiotemporal parameters in nine healthy subjects. A PFCC motorized mechanism was designed that incorporated twin sole plates, the movements of which enabled increased toe to floor clearance during swing phase. A prototype was constructed in combination with an IRGO, and hence was re-named as an IRGO-PFCC orthosis. The effects of IRGO-PFCC usage on the spatiotemporal parameters and trunk compensatory movements during walking were then analyzed under two conditions, firstly with the PFCC 'active' i.e., with the motorized device functioning, and secondly inactive, where floor clearance was standard. Ambulating with IRGO-PFCC orthosis resulted in reduction in the spatiotemporal parameters of gait (speed of walking, cadence and stride length) in nine healthy subjects. Walking with IRGO-PFCC orthosis led to significant differences in lateral (p = .007) and vertical (p = .008) trunk compensatory movements. In other words, through using IRGO-PFCC orthosis, the lateral and vertical trunk compensatory movements decreased by 51.32% and 42.7%, respectively. An adapted PFCC mechanism, with a relatively small motor and power supply could effectively increase toe to floor clearance during swing phase and thereby decrease trunk compensatory motions and potentially improve energy consumption. Implications for rehabilitations •The High rejection rates of reciprocal gait orthoses are related to the increasing in energy expenditure and burden loads on the upper limb joints during walking following trunk compensatory movements.•An original powered foot clearance creator mechanism was designed and constructed to assisting floor clearance capability and reduce trunk compensatory movements in subjects with spinal cord injury during

Mobile Phenotyping System Using an Aeromotively Stabilized Cable-Driven Robot

Science.gov (United States)

Newman, M. B.; Zygielbaum, A. I.

2017-12-01

Agricultural researchers are constantly attempting to generate superior agricultural crops. Whether this means creating crops with greater yield, crops that are more resilient to disease, or crops that can tolerate harsh environments with fewer failures, test plots of these experimental crops must be studied in real-world environments with minimal invasion to determine how they will perform in full-scale agricultural settings. To monitor these crops without interfering with their natural growth, a noninvasive sensor system has been implemented. This system, instituted by the College of Agricultural Sciences and Natural Resources at the University of Nebraska - Lincoln (UNL), uses a system of poles, cables, and winches to support and maneuver a sensor platform above the crops at an outdoor phenotyping site. In this work, we improve upon the UNL outdoor phenotyping system presenting the concept design for a mobile, cable-driven phenotyping system as opposed to a permanent phenotyping facility. One major challenge in large-scale, cable-driven robots is stability of the end-effector. As a result, this mobile system seeks to use a novel method of end-effector stabilization using an onboard rotor drive system, herein referred to as the Instrument Platform Aeromotive Stabilization System (IPASS). A prototype system is developed and analyzed to determine the viability of IPASS.

Design and Voluntary Motion Intention Estimation of a Novel Wearable Full-Body Flexible Exoskeleton Robot

Directory of Open Access Journals (Sweden)

Chunjie Chen

2017-01-01

Full Text Available The wearable full-body exoskeleton robot developed in this study is one application of mobile cyberphysical system (CPS, which is a complex mobile system integrating mechanics, electronics, computer science, and artificial intelligence. Steel wire was used as the flexible transmission medium and a group of special wire-locking structures was designed. Additionally, we designed passive joints for partial joints of the exoskeleton. Finally, we proposed a novel gait phase recognition method for full-body exoskeletons using only joint angular sensors, plantar pressure sensors, and inclination sensors. The method consists of four procedures. Firstly, we classified the three types of main motion patterns: normal walking on the ground, stair-climbing and stair-descending, and sit-to-stand movement. Secondly, we segregated the experimental data into one gait cycle. Thirdly, we divided one gait cycle into eight gait phases. Finally, we built a gait phase recognition model based on k-Nearest Neighbor perception and trained it with the phase-labeled gait data. The experimental result shows that the model has a 98.52% average correct rate of classification of the main motion patterns on the testing set and a 95.32% average correct rate of phase recognition on the testing set. So the exoskeleton robot can achieve human motion intention in real time and coordinate its movement with the wearer.

Effect of Ankle-foot Orthosis on Lower Limb Muscle Activities and Static Balance of Stroke Patients Authors’ Names

OpenAIRE

Lee, Youngmin; Her, Jin Gang; Choi, Youngeun; Kim, Heesoo

2014-01-01

[Purpose] This study examined the effects of an ankle-foot orthosis worn during balance training on lower limb muscle activity and static balance of chronic stroke patients. [Subjects] The subjects were twenty-five inpatients receiving physical therapy for chronic stroke. [Methods] The chronic stroke patients were divided into two groups: thirteen patients were assigned to the ankle-foot orthosis group, while the remaining twelve patients wore only their shoes. Each group performed balance tr...

Assessment of the Sheffield Support Snood, an innovative cervical orthosis designed for people affected by neck muscle weakness

OpenAIRE

Pancani, Silvia; Rowson, Jennifer; Tindale, Wendy; Heron, Nicola; Langley, Joe; McCarthy, Avril D.; Quinn, Ann; Reed, Heath; Stanton, Andrew; Shaw, Pamela J.; McDermott, Christopher J.; Mazzà, Claudia

2016-01-01

The aim of this study was to quantify the biomechanical features of the Sheffield Support Snood (SSS), a cervical orthosis specifically designed for patients with neck weakness. The orthosis is designed to be adaptable to a patient’s level of functional limitation using adjustable removable supports, which contribute support and restrict movement only in desired anatomical planes. \\ud Methods: The SSS was evaluated along with two commercially available orthoses, the Vista and Headmaster. The ...

CMS cavern inspection robot

CERN Document Server

Ibrahim, Ibrahim

2017-01-01

Robots which are immune to the CMS cavern environment, wirelessly controlled: -One actuated by smart materials (Ionic Polymer-Metal Composites and Macro Fiber Composites) -One regular brushed DC rover -One servo-driven rover -Stair-climbing robot

Early rehabilitation treatment combined with equinovarus foot deformity surgical correction in stroke patients: safety and changes in gait parameters.

Science.gov (United States)

Giannotti, Erika; Merlo, Andrea; Zerbinati, Paolo; Longhi, Maria; Prati, Paolo; Masiero, Stefano; Mazzoli, Davide

2016-06-01

Equinovarus foot deformity (EVFD) compromises several prerequisites of walking and increases the risk of falling. Guidelines on rehabilitation following EVFD surgery are missing in current literature. The aim of this study was to analyze safety and adherence to an early rehabilitation treatment characterized by immediate weight bearing with an ankle-foot orthosis (AFO) in hemiplegic patients after EVFD surgery and to describe gait changes after EVFD surgical correction combined with early rehabilitation treatment. Retrospective observational cohort study. Inpatient rehabilitation clinic. Forty-seven adult patients with hemiplegia consequent to ischemic or haemorrhagic stroke (L/R 20/27, age 56±15 years, time from lesion 6±5 years). A specific rehabilitation protocol with a non-articulated AFO, used to allow for immediate gait training, started one day after EVFD surgery. Gait analysis (GA) data before and one month after surgery were analyzed. The presence of differences in GA space-time parameters, in ankle dorsiflexion (DF) values and peaks at initial contact (DF at IC), during stance (DF at St) and swing (DF at Sw) were assessed by the Wilcoxon Test while the presence of correlations between pre- and post-operative values by Spearman's correlation coefficient. All patients completed the rehabilitation protocol and no clinical complications occurred in the sample. Ankle DF increased one month after surgery at all investigated gait phases (Wilcoxon Test, Prehabilitation associated with surgical procedure is safe and may be suitable to correct EVFD by restoring both the neutral heel foot-ground contact and the ankle DF peaks during stance and swing at one month from surgery. The proposed protocol is a safe and potentially useful rehabilitative approach after EVFD surgical correction in stroke patients.

Biologically-Inspired Adaptive Obstacle Negotiation Behavior of Hexapod Robots

DEFF Research Database (Denmark)

Goldschmidt, Dennis; Wörgötter, Florentin; Manoonpong, Poramate

2014-01-01

by these findings, we present an adaptive neural control mechanism for obstacle negotiation behavior in hexapod robots. It combines locomotion control, backbone joint control, local leg reflexes, and neural learning. While the first three components generate locomotion including walking and climbing, the neural...... learning mechanism allows the robot to adapt its behavior for obstacle negotiation with respect to changing conditions, e.g., variable obstacle heights and different walking gaits. By successfully learning the association of an early, predictive signal (conditioned stimulus, CS) and a late, reflex signal...... (unconditioned stimulus, UCS), both provided by ultrasonic sensors at the front of the robot, the robot can autonomously find an appropriate distance from an obstacle to initiate climbing. The adaptive neural control was developed and tested first on a physical robot simulation, and was then successfully...

Role of three side support ankle–foot orthosis in improving the ...

African Journals Online (AJOL)

Cerebral palsy (CP) is a heterogeneous group of permanent, non-progressive motor disorders of movement and posture. Ankle–foot orthoses (AFOs) are frequently prescribed to correct skeletal misalignments in spastic CP. The present study aims to evaluate the effect of the three side support ankle–foot orthosis on ...

Capability of 2 gait measures for detecting response to gait training in stroke survivors: Gait Assessment and Intervention Tool and the Tinetti Gait Scale.

Science.gov (United States)

Zimbelman, Janice; Daly, Janis J; Roenigk, Kristen L; Butler, Kristi; Burdsall, Richard; Holcomb, John P

2012-01-01

To characterize the performance of 2 observational gait measures, the Tinetti Gait Scale (TGS) and the Gait Assessment and Intervention Tool (G.A.I.T.), in identifying improvement in gait in response to gait training. In secondary analysis from a larger study of multimodal gait training for stroke survivors, we measured gait at pre-, mid-, and posttreatment according to G.A.I.T. and TGS, assessing their capability to capture recovery of coordinated gait components. Large medical center. Cohort of stroke survivors (N=44) greater than 6 months after stroke. All subjects received 48 sessions of a multimodal gait-training protocol. Treatment consisted of 1.5 hours per session, 4 sessions per week for 12 weeks, receiving these 3 treatment aspects: (1) coordination exercise, (2) body weight-supported treadmill training, and (3) overground gait training, with 46% of subjects receiving functional electrical stimulation. All subjects were evaluated with the G.A.I.T. and TGS before and after completing the 48-session intervention. An additional evaluation was performed at midtreatment (after session 24). For the total subject sample, there were significant pre-/post-, pre-/mid-, and mid-/posttreatment gains for both the G.A.I.T. and the TGS. According to the G.A.I.T., 40 subjects (91%) showed improved scores, 2 (4%) no change, and 2 (4%) a worsening score. According to the TGS, only 26 subjects (59%) showed improved scores, 16 (36%) no change, and 1 (2%) a worsening score. For 1 treatment group of chronic stroke survivors, the TGS failed to identify a significant treatment response to gait training, whereas the G.A.I.T. measure was successful. The G.A.I.T. is more sensitive than the TGS for individual patients and group treatment response in identifying recovery of volitional control of gait components in response to gait training. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

A Critical Analysis of a Hand Orthosis Reverse Engineering and 3D Printing Process

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Gabriele Baronio

2016-01-01

Full Text Available The possibility to realize highly customized orthoses is receiving boost thanks to the widespread diffusion of low-cost 3D printing technologies. However, rapid prototyping (RP with 3D printers is only the final stage of patient personalized orthotics processes. A reverse engineering (RE process is in fact essential before RP, to digitize the 3D anatomy of interest and to process the obtained surface with suitable modeling software, in order to produce the virtual solid model of the orthosis to be printed. In this paper, we focus on the specific and demanding case of the customized production of hand orthosis. We design and test the essential steps of the entire production process with particular emphasis on the accurate acquisition of the forearm geometry and on the subsequent production of a printable model of the orthosis. The choice of the various hardware and software tools (3D scanner, modeling software, and FDM printer is aimed at the mitigation of the design and production costs while guaranteeing suitable levels of data accuracy, process efficiency, and design versatility. Eventually, the proposed method is critically analyzed so that the residual issues and critical aspects are highlighted in order to discuss possible alternative approaches and to derive insightful observations that could guide future research activities.

Robust Control of a Cable-Driven Soft Exoskeleton Joint for Intrinsic Human-Robot Interaction.

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Jarrett, C; McDaid, A J

2017-07-01

A novel, cable-driven soft joint is presented for use in robotic rehabilitation exoskeletons to provide intrinsic, comfortable human-robot interaction. The torque-displacement characteristics of the soft elastomeric core contained within the joint are modeled. This knowledge is used in conjunction with a dynamic system model to derive a sliding mode controller (SMC) to implement low-level torque control of the joint. The SMC controller is experimentally compared with a baseline feedback-linearised proportional-derivative controller across a range of conditions and shown to be robust to un-modeled disturbances. The torque controller is then tested with six healthy subjects while they perform a selection of activities of daily living, which has validated its range of performance. Finally, a case study with a participant with spastic cerebral palsy is presented to illustrate the potential of both the joint and controller to be used in a physiotherapy setting to assist clinical populations.

A three-dimensional model to assess the effect of ankle joint axis misalignments in ankle-foot orthoses.

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Fatone, Stefania; Johnson, William Brett; Tucker, Kerice

2016-04-01

Misalignment of an articulated ankle-foot orthosis joint axis with the anatomic joint axis may lead to discomfort, alterations in gait, and tissue damage. Theoretical, two-dimensional models describe the consequences of misalignments, but cannot capture the three-dimensional behavior of ankle-foot orthosis use. The purpose of this project was to develop a model to describe the effects of ankle-foot orthosis ankle joint misalignment in three dimensions. Computational simulation. Three-dimensional scans of a leg and ankle-foot orthosis were incorporated into a link segment model where the ankle-foot orthosis joint axis could be misaligned with the anatomic ankle joint axis. The leg/ankle-foot orthosis interface was modeled as a network of nodes connected by springs to estimate interface pressure. Motion between the leg and ankle-foot orthosis was calculated as the ankle joint moved through a gait cycle. While the three-dimensional model corroborated predictions of the previously published two-dimensional model that misalignments in the anterior -posterior direction would result in greater relative motion compared to misalignments in the proximal -distal direction, it provided greater insight showing that misalignments have asymmetrical effects. The three-dimensional model has been incorporated into a freely available computer program to assist others in understanding the consequences of joint misalignments. Models and simulations can be used to gain insight into functioning of systems of interest. We have developed a three-dimensional model to assess the effect of ankle joint axis misalignments in ankle-foot orthoses. The model has been incorporated into a freely available computer program to assist understanding of trainees and others interested in orthotics. © The International Society for Prosthetics and Orthotics 2014.

One- or Two-Legged Standing: What Is the More Suitable Protocol to Assess the Postural Effects of the Rigid Ankle Orthosis?

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Rougier, Patrice; Genthon, Nicolas; Gallois-Montbrun, Thibault; Brugiere, Steve; Bouvat, Eric

2009-01-01

To highlight the capacity of one- and two-legged standing protocols when assessing postural behavior induced by a rigid ankle orthosis, 14 healthy individuals stood upright barefoot and wore either an elastic stocking on the preferred leg or a rigid orthosis with or without additional taping in one- or two-legged (TL) conditions. Traditional…

Tactile surface classification for limbed robots using a pressure sensitive robot skin

International Nuclear Information System (INIS)

Shill, Jacob J; Collins Jr, Emmanuel G; Coyle, Eric; Clark, Jonathan

2015-01-01

This paper describes an approach to terrain identification based on pressure images generated through direct surface contact using a robot skin constructed around a high-resolution pressure sensing array. Terrain signatures for classification are formulated from the magnitude frequency responses of the pressure images. The initial experimental results for statically obtained images show that the approach yields classification accuracies >98%. The methodology is extended to accommodate the dynamic pressure images anticipated when a robot is walking or running. Experiments with a one-legged hopping robot yield similar identification accuracies ≈99%. In addition, the accuracies are independent with respect to changing robot dynamics (i.e., when using different leg gaits). The paper further shows that the high-resolution capabilities of the sensor enables similarly textured surfaces to be distinguished. A correcting filter is developed to accommodate for failures or faults that inevitably occur within the sensing array with continued use. Experimental results show using the correcting filter can extend the effective operational lifespan of a high-resolution sensing array over 6x in the presence of sensor damage. The results presented suggest this methodology can be extended to autonomous field robots, providing a robot with crucial information about the environment that can be used to aid stable and efficient mobility over rough and varying terrains. (paper)

Effect of medial arch support foot orthosis on plantar pressure distribution in females with mild-to-moderate hallux valgus after one month of follow-up.

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Farzadi, Maede; Safaeepour, Zahra; Mousavi, Mohammad E; Saeedi, Hassan

2015-04-01

Higher plantar pressures at the medial forefoot are reported in hallux valgus. Foot orthoses with medial arch support are considered as an intervention in this pathology. However, little is known about the effect of foot orthoses on plantar pressure distribution in hallux valgus. To investigate the effect of a foot orthosis with medial arch support on pressure distribution in females with mild-to-moderate hallux valgus. Quasi-experimental. Sixteen female volunteers with mild-to-moderate hallux valgus participated in this study and used a medial arch support foot orthosis for 4 weeks. Plantar pressure for each participant was assessed using the Pedar-X(®) in-shoe system in four conditions including shoe-only and foot orthosis before and after the intervention. The use of the foot orthosis for 1 month led to a decrease in peak pressure and maximum force under the hallux, first metatarsal, and metatarsals 3-5 (p hallux and the first metatarsal head by transferring the load to the other regions. It would appear that this type of foot orthosis can be an effective method of intervention in this pathology. Findings of this study will improve the clinical knowledge about the effect of the medial arch support foot orthosis used on plantar pressure distribution in hallux valgus pathology. © The International Society for Prosthetics and Orthotics 2014.

Development of an assist controller with robot suit HAL for hemiplegic patients using motion data on the unaffected side.

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Kawamoto, Hiroaki; Kandone, Hideki; Sakurai, Takeru; Ariyasu, Ryohei; Ueno, Yukiko; Eguchi, Kiyoshi; Sankai, Yoshiyuki

2014-01-01

Among several characteristics seen in gait of hemiplegic patients after stroke, symmetry is known to be an indicator of the degree of impairment of walking ability. This paper proposes a control method for a wearable type lower limb motion assist robot to realize spontaneous symmetric gait for these individuals. This control method stores the motion of the unaffected limb during swing and then provides motion support on the affected limb during the subsequent swing using the stored pattern to realize symmetric gait based on spontaneous limb swing. This method is implemented on the robot suit HAL (Hybrid Assistive Limbs). Clinical tests were conducted in order to assess the feasibility of the control method. Our case study involved participation of one chronic stroke patient who was not able to flex his right knee. As a result, the walking support for hemiplegic leg provided by the HAL improved the subject's gait symmetry. The feasibility study showed promising basis for the future clinical study.

Preliminary results of BRAVO project: brain computer interfaces for Robotic enhanced Action in Visuo-motOr tasks.

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Bergamasco, Massimo; Frisoli, Antonio; Fontana, Marco; Loconsole, Claudio; Leonardis, Daniele; Troncossi, Marco; Foumashi, Mohammad Mozaffari; Parenti-Castelli, Vincenzo

2011-01-01

This paper presents the preliminary results of the project BRAVO (Brain computer interfaces for Robotic enhanced Action in Visuo-motOr tasks). The objective of this project is to define a new approach to the development of assistive and rehabilitative robots for motor impaired users to perform complex visuomotor tasks that require a sequence of reaches, grasps and manipulations of objects. BRAVO aims at developing new robotic interfaces and HW/SW architectures for rehabilitation and regain/restoration of motor function in patients with upper limb sensorimotor impairment through extensive rehabilitation therapy and active assistance in the execution of Activities of Daily Living. The final system developed within this project will include a robotic arm exoskeleton and a hand orthosis that will be integrated together for providing force assistance. The main novelty that BRAVO introduces is the control of the robotic assistive device through the active prediction of intention/action. The system will actually integrate the information about the movement carried out by the user with a prediction of the performed action through an interpretation of current gaze of the user (measured through eye-tracking), brain activation (measured through BCI) and force sensor measurements. © 2011 IEEE

Case report on the use of a functional electrical orthosis in rehabilitation of upper limb function in a chronic stroke patient

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Catalin Moghioroiu

2018-05-01

Full Text Available Introduction. The increasing incidence of strokes and their occurrence in younger active people require the development of solutions that allow participation, despite the debilitating deficit that is not always solved by rehabilitation. The present report shows such a potential solution. Objective. In this presentation we will show the effects of using a functional electric orthosis, the high number of repetitions and daily electrostimulation in a young stroke patient with motor deficit in the upper limb, the difficulties encountered in attempting to use orthosis, the results and the course of its recovery over the years. Materials and Methods. The present report shows the evolution of a 31-year-old female patient with hemiplegia, resulting from a hemorrhagic stroke, from the moment of surgery to the moment of purchasing a functional electrical orthosis and a few months later, highlighting a 3-week period when the training method focused on performing a large number of repetitions of a single exercise helped by the orthosis – 3 weekly physical therapy sessions, with a duration of one hour and 15 minutes, plus 2 electrostimulation sessions lasting 20 minutes each and 100 elbow extension, daily, 6 times a week. The patient was evaluated and filmed at the beginning and end of the 3 week period. The patient's consent was obtained for the use of the data and images presented. Results. Invalidating motor deficiency and problems specific to the use of upper limb functional electrostimulation in patients with stroke sequelae (flexion synergy, exaggeration of reflex response, wrist position during stimulation, etc. made it impossible to use orthosis in functional activities within ADL although it allowed the achievement of a single task. Evaluation on the FuglMayer assessment does not show any quantifiable progress, although it is possible to have slightly improved the control of the shoulder and elbow and increased the speed of task execution

Generating Human-Like Velocity-Adapted Jumping Gait from sEMG Signals for Bionic Leg’s Control

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Weiwei Yu

2017-01-01

Full Text Available In the case of dynamic motion such as jumping, an important fact in sEMG (surface Electromyogram signal based control on exoskeletons, myoelectric prostheses, and rehabilitation gait is that multichannel sEMG signals contain mass data and vary greatly with time, which makes it difficult to generate compliant gait. Inspired by the fact that muscle synergies leading to dimensionality reduction may simplify motor control and learning, this paper proposes a new approach to generate flexible gait based on muscle synergies extracted from sEMG signal. Two questions were discussed and solved, the first one concerning whether the same set of muscle synergies can explain the different phases of hopping movement with various velocities. The second one is about how to generate self-adapted gait with muscle synergies while alleviating model sensitivity to sEMG transient changes. From the experimental results, the proposed method shows good performance both in accuracy and in robustness for producing velocity-adapted vertical jumping gait. The method discussed in this paper provides a valuable reference for the sEMG-based control of bionic robot leg to generate human-like dynamic gait.

Stress distribution of the foot during mid-stance to push-off in barefoot gait: a 3-D finite element analysis.

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Chen, W P; Tang, F T; Ju, C W

2001-08-01

To quantify stress distribution of the foot during mid-stance to push-off in barefoot gait using 3-D finite element analysis. To simulate the foot structure and facilitate later consideration of footwear. Finite element model was generated and loading condition simulating barefoot gait during mid-stance to push-off was used to quantify the stress distributions. A computational model can provide overall stress distributions of the foot subject to various loading conditions. A preliminary 3-D finite element foot model was generated based on the computed tomography data of a male subject and the bone and soft tissue structures were modeled. Analysis was performed for loading condition simulating barefoot gait during mid-stance to push-off. The peak plantar pressure ranged from 374 to 1003 kPa and the peak von Mises stress in the bone ranged from 2.12 to 6.91 MPa at different instants. The plantar pressure patterns were similar to measurement result from previous literature. The present study provides a preliminary computational model that is capable of estimating the overall plantar pressure and bone stress distributions. It can also provide quantitative analysis for normal and pathological foot motion. This model can identify areas of increased pressure and correlate the pressure with foot pathology. Potential applications can be found in the study of foot deformities, footwear, surgical interventions. It may assist pre-treatment planning, design of pedorthotic appliances, and predict the treatment effect of foot orthosis.

Value-driven behavior generation for an autonomous mobile ground robot

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Balakirsky, Stephen B.; Lacaze, Alberto

2002-07-01

In this paper, we will describe a value-driven graph search technique that is capable of generating a rich variety of single and multiple vehicle behaviors. The generation of behaviors depends on cost and benefit computations that may involve terrain characteristics, line of sight to enemy positions, and cost, benefit, and risk of traveling on roads. Depending on mission priorities and cost values, real-time planners can autonomously build appropriate behaviors on the fly that include road following, cross-country movement, stealthily movement, formation keeping, and bounding overwatch. This system follows NIST's 4D/RCS architecture, and a discussion of the world model, value judgment, and behavior generation components is provided. In addition, techniques for collapsing a multidimensional model space into a cost space and planning graph constraints are discussed. The work described in this paper has been performed under the Army Research Laboratory's Robotics Demo III program.

Impedance Control of the Rehabilitation Robot Based on Sliding Mode Control

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Zhou, Jiawang; Zhou, Zude; Ai, Qingsong

As an auxiliary treatment, the 6-DOF parallel robot plays an important role in lower limb rehabilitation. In order to improve the efficiency and flexibility of the lower limb rehabilitation training, this paper studies the impedance controller based on the position control. A nonsingular terminal sliding mode control is developed to ensure the trajectory tracking precision and in contrast to traditional PID control strategy in the inner position loop, the system will be more stable. The stability of the system is proved by Lyapunov function to guarantee the convergence of the control errors. Simulation results validate the effectiveness of the target impedance model and show that the parallel robot can adjust gait trajectory online according to the human-machine interaction force to meet the gait request of patients, and changing the impedance parameters can meet the demands of different stages of rehabilitation training.

A mechanized gait trainer for restoration of gait.

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Hesse, S; Uhlenbrock, D

2000-01-01

The newly developed gait trainer allows wheel-chair-bound subjects the repetitive practice of a gait-like movement without overstressing therapists. The device simulates the phases of gait, supports the subjects according to their abilities, and controls the center of mass (CoM) in the vertical and horizontal directions. The patterns of sagittal lower limb joint kinematics and of muscle activation for a normal subject were similar when using the mechanized trainer and when walking on a treadmill. A non-ambulatory hemiparetic subject required little help from one therapist on the gait trainer, while two therapists were required to support treadmill walking. Gait movements on the trainer were highly symmetrical, impact free, and less spastic. The vertical displacement of the CoM was bi-phasic instead of mono-phasic during each gait cycle on the new device. Two cases of non-ambulatory patients, who regained their walking ability after 4 weeks of daily training on the gait trainer, are reported.

Movement Performance of Human-Robot Cooperation Control Based on EMG-Driven Hill-Type and Proportional Models for an Ankle Power-Assist Exoskeleton Robot.

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Ao, Di; Song, Rong; Gao, JinWu

2017-08-01

Although the merits of electromyography (EMG)-based control of powered assistive systems have been certified, the factors that affect the performance of EMG-based human-robot cooperation, which are very important, have received little attention. This study investigates whether a more physiologically appropriate model could improve the performance of human-robot cooperation control for an ankle power-assist exoskeleton robot. To achieve the goal, an EMG-driven Hill-type neuromusculoskeletal model (HNM) and a linear proportional model (LPM) were developed and calibrated through maximum isometric voluntary dorsiflexion (MIVD). The two control models could estimate the real-time ankle joint torque, and HNM is more accurate and can account for the change of the joint angle and muscle dynamics. Then, eight healthy volunteers were recruited to wear the ankle exoskeleton robot and complete a series of sinusoidal tracking tasks in the vertical plane. With the various levels of assist based on the two calibrated models, the subjects were instructed to track the target displayed on the screen as accurately as possible by performing ankle dorsiflexion and plantarflexion. Two measurements, the root mean square error (RMSE) and root mean square jerk (RMSJ), were derived from the assistant torque and kinematic signals to characterize the movement performances, whereas the amplitudes of the recorded EMG signals from the tibialis anterior (TA) and the gastrocnemius (GAS) were obtained to reflect the muscular efforts. The results demonstrated that the muscular effort and smoothness of tracking movements decreased with an increase in the assistant ratio. Compared with LPM, subjects made lower physical efforts and generated smoother movements when using HNM, which implied that a more physiologically appropriate model could enable more natural and human-like human-robot cooperation and has potential value for improvement of human-exoskeleton interaction in future applications.

On the road to a neuroprosthetic hand: a novel hand grasp orthosis based on functional electrical stimulation.

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Leeb, Robert; Gubler, Miguel; Tavella, Michele; Miller, Heather; Del Millan, Jose R

2010-01-01

To patients who have lost the functionality of their hands as a result of a severe spinal cord injury or brain stroke, the development of new techniques for grasping is indispensable for reintegration and independency in daily life. Functional Electrical Stimulation (FES) of residual muscles can reproduce the most dominant grasping tasks and can be initialized by brain signals. However, due to the very complex hand anatomy and current limitations in FES-technology with surface electrodes, these grasp patterns cannot be smoothly executed. In this paper, we present an adaptable passive hand orthosis which is capable of producing natural and smooth movements when coupled with FES. It evenly synchronizes the grasping movements and applied forces on all fingers, allowing for naturalistic gestures and functional grasps of everyday objects. The orthosis is also equipped with a lock, which allows it to remain in the desired position without the need for long-term stimulation. Furthermore, we quantify improvements offered by the orthosis compare them with natural grasps on healthy subjects.

First Steps Towards Translating HZD Control of Bipedal Robots to Decentralized Control of Exoskeletons

OpenAIRE

Agrawal, Ayush; Harib, Omar; Hereid, Ayonga; Finet, Sylvain; Masselin, Matthieu; Praly, Laurent; Ames, Aaron D.; Sreenath, Koushil; Grizzle, Jessy W.

2017-01-01

This paper presents preliminary results toward translating gait and control design for bipedal robots to decentralized control of an exoskeleton aimed at restoring mobility to patients with lower limb paralysis, without the need for crutches. A mathematical hybrid dynamical model of the human-exoskeleton system is developed and a library of dynamically feasible periodic walking gaits for different walking speeds is found through nonlinear constrained optimization using the full-order dynamica...

The Combined Effects of Body Weight Support and Gait Speed on Gait Related Muscle Activity: A Comparison between Walking in the Lokomat Exoskeleton and Regular Treadmill Walking

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Van Kammen, Klaske; Boonstra, Annemarijke; Reinders-Messelink, Heleen; den Otter, Rob

2014-01-01

Background For the development of specialized training protocols for robot assisted gait training, it is important to understand how the use of exoskeletons alters locomotor task demands, and how the nature and magnitude of these changes depend on training parameters. Therefore, the present study assessed the combined effects of gait speed and body weight support (BWS) on muscle activity, and compared these between treadmill walking and walking in the Lokomat exoskeleton. Methods Ten healthy participants walked on a treadmill and in the Lokomat, with varying levels of BWS (0% and 50% of the participants’ body weight) and gait speed (0.8, 1.8, and 2.8 km/h), while temporal step characteristics and muscle activity from Erector Spinae, Gluteus Medius, Vastus Lateralis, Biceps Femoris, Gastrocnemius Medialis, and Tibialis Anterior muscles were recorded. Results The temporal structure of the stepping pattern was altered when participants walked in the Lokomat or when BWS was provided (i.e. the relative duration of the double support phase was reduced, and the single support phase prolonged), but these differences normalized as gait speed increased. Alternations in muscle activity were characterized by complex interactions between walking conditions and training parameters: Differences between treadmill walking and walking in the exoskeleton were most prominent at low gait speeds, and speed effects were attenuated when BWS was provided. Conclusion Walking in the Lokomat exoskeleton without movement guidance alters the temporal step regulation and the neuromuscular control of walking, although the nature and magnitude of these effects depend on complex interactions with gait speed and BWS. If normative neuromuscular control of gait is targeted during training, it is recommended that very low speeds and high levels of BWS should be avoided when possible. PMID:25226302

Navigation Strategy by Contact Sensing Interaction for a Biped Humanoid Robot

Directory of Open Access Journals (Sweden)

Hanafiah Yussof

2008-11-01

Full Text Available This report presents a basic contact interaction-based navigation strategy for a biped humanoid robot to support current visual-based navigation. The robot's arms were equipped with force sensors to detect physical contact with objects. We proposed a motion algorithm consisting of searching tasks, self-localization tasks, correction of locomotion direction tasks and obstacle avoidance tasks. Priority was given to right-side direction to navigate the robot locomotion. Analysis of trajectory generation, biped gait pattern, and biped walking characteristics was performed to define an efficient navigation strategy in a biped walking humanoid robot. The proposed algorithm is evaluated in an experiment with a 21-dofs humanoid robot operating in a room with walls and obstacles. The experimental results reveal good robot performance when recognizing objects by touching, grasping, and continuously generating suitable trajectories to correct direction and avoid collisions.

Multi-Axis Force Sensor for Human-Robot Interaction Sensing in a Rehabilitation Robotic Device.

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Grosu, Victor; Grosu, Svetlana; Vanderborght, Bram; Lefeber, Dirk; Rodriguez-Guerrero, Carlos

2017-06-05

Human-robot interaction sensing is a compulsory feature in modern robotic systems where direct contact or close collaboration is desired. Rehabilitation and assistive robotics are fields where interaction forces are required for both safety and increased control performance of the device with a more comfortable experience for the user. In order to provide an efficient interaction feedback between the user and rehabilitation device, high performance sensing units are demanded. This work introduces a novel design of a multi-axis force sensor dedicated for measuring pelvis interaction forces in a rehabilitation exoskeleton device. The sensor is conceived such that it has different sensitivity characteristics for the three axes of interest having also movable parts in order to allow free rotations and limit crosstalk errors. Integrated sensor electronics make it easy to acquire and process data for a real-time distributed system architecture. Two of the developed sensors are integrated and tested in a complex gait rehabilitation device for safe and compliant control.

The immediate effects of robot-assistance on energy consumption and cardiorespiratory load during walking compared to walking without robot-assistance: a systematic review.

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Lefeber, Nina; Swinnen, Eva; Kerckhofs, Eric

2017-10-01

The integration of sufficient cardiovascular stress into robot-assisted gait (RAG) training could combine the benefits of both RAG and aerobic training. The aim was to summarize literature data on the immediate effects of RAG compared to walking without robot-assistance on metabolic-, cardiorespiratory- and fatigue-related parameters. PubMed and Web of Science were searched for eligible articles till February 2016. Means, SDs and significance values were extracted. Effect sizes were calculated. Fourteen studies were included, concerning 155 participants (85 healthy subjects, 39 stroke and 31 spinal cord injury patients), 9 robots (2 end-effectors, 1 treadmill-based and 6 wearable exoskeletons), and 7 outcome parameters (mostly oxygen consumption and heart rate). Overall, metabolic and cardiorespiratory parameters were lower during RAG compared to walking without robot-assistance (moderate to large effect sizes). In healthy subjects, when no body-weight support (BWS) was provided, RAG with an end-effector device was more energy demanding than walking overground (p > .05, large effect sizes). Generally, results suggest that RAG is less energy-consuming and cardiorespiratory stressful than walking without robot-assistance, but results depend on factors such as robot type, walking speed, BWS and effort. Additional research is needed to draw firm conclusions. Implications for Rehabilitation Awareness of the energy consumption and cardiorespiratory load of robot-assisted gait (RAG) training is important in the rehabilitation of (neurological) patients with impaired cardiorespiratory fitness and patients who are at risk of cardiovascular diseases. On the other hand, the integration of sufficient cardiometabolic stress in RAG training could combine the effects of both RAG and aerobic training. Energy consumption and cardiorespiratory load during walking with robot-assistance seems to depend on factors such as robot type, walking speed, body-weight support or amount of

Gait post-stroke: Pathophysiology and rehabilitation strategies.

Science.gov (United States)

Beyaert, C; Vasa, R; Frykberg, G E

2015-11-01

We reviewed neural control and biomechanical description of gait in both non-disabled and post-stroke subjects. In addition, we reviewed most of the gait rehabilitation strategies currently in use or in development and observed their principles in relation to recent pathophysiology of post-stroke gait. In both non-disabled and post-stroke subjects, motor control is organized on a task-oriented basis using a common set of a few muscle modules to simultaneously achieve body support, balance control, and forward progression during gait. Hemiparesis following stroke is due to disruption of descending neural pathways, usually with no direct lesion of the brainstem and cerebellar structures involved in motor automatic processes. Post-stroke, improvements of motor activities including standing and locomotion are variable but are typically characterized by a common postural behaviour which involves the unaffected side more for body support and balance control, likely in response to initial muscle weakness of the affected side. Various rehabilitation strategies are regularly used or in development, targeting muscle activity, postural and gait tasks, using more or less high-technology equipment. Reduced walking speed often improves with time and with various rehabilitation strategies, but asymmetric postural behaviour during standing and walking is often reinforced, maintained, or only transitorily decreased. This asymmetric compensatory postural behaviour appears to be robust, driven by support and balance tasks maintaining the predominant use of the unaffected side over the initially impaired affected side. Based on these elements, stroke rehabilitation including affected muscle strengthening and often stretching would first need to correct the postural asymmetric pattern by exploiting postural automatic processes in various particular motor tasks secondarily beneficial to gait. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Online Phase Detection Using Wearable Sensors for Walking with a Robotic Prosthesis

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Maja Goršič

2014-02-01

Full Text Available This paper presents a gait phase detection algorithm for providing feedback in walking with a robotic prosthesis. The algorithm utilizes the output signals of a wearable wireless sensory system incorporating sensorized shoe insoles and inertial measurement units attached to body segments. The principle of detecting transitions between gait phases is based on heuristic threshold rules, dividing a steady-state walking stride into four phases. For the evaluation of the algorithm, experiments with three amputees, walking with the robotic prosthesis and wearable sensors, were performed. Results show a high rate of successful detection for all four phases (the average success rate across all subjects >90%. A comparison of the proposed method to an off-line trained algorithm using hidden Markov models reveals a similar performance achieved without the need for learning dataset acquisition and previous model training.

Laser-Driven Very High Energy Electron/Photon Beam Radiation Therapy in Conjunction with a Robotic System

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Kazuhisa Nakajima

2014-12-01

Full Text Available We present a new external-beam radiation therapy system using very-high-energy (VHE electron/photon beams generated by a centimeter-scale laser plasma accelerator built in a robotic system. Most types of external-beam radiation therapy are delivered using a machine called a medical linear accelerator driven by radio frequency (RF power amplifiers, producing electron beams with an energy range of 6–20 MeV, in conjunction with modern radiation therapy technologies for effective shaping of three-dimensional dose distributions and spatially accurate dose delivery with imaging verification. However, the limited penetration depth and low quality of the transverse penumbra at such electron beams delivered from the present RF linear accelerators prevent the implementation of advanced modalities in current cancer treatments. These drawbacks can be overcome if the electron energy is increased to above 50 MeV. To overcome the disadvantages of the present RF-based medical accelerators, harnessing recent advancement of laser-driven plasma accelerators capable of producing 1-GeV electron beams in a 1-cm gas cell, we propose a new embodiment of the external-beam radiation therapy robotic system delivering very high-energy electron/photon beams with an energy of 50–250 MeV; it is more compact, less expensive, and has a simpler operation and higher performance in comparison with the current radiation therapy system.

Octopus-inspired multi-arm robotic swimming.

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Sfakiotakis, M; Kazakidi, A; Tsakiris, D P

2015-05-13

The outstanding locomotor and manipulation characteristics of the octopus have recently inspired the development, by our group, of multi-functional robotic swimmers, featuring both manipulation and locomotion capabilities, which could be of significant engineering interest in underwater applications. During its little-studied arm-swimming behavior, as opposed to the better known jetting via the siphon, the animal appears to generate considerable propulsive thrust and rapid acceleration, predominantly employing movements of its arms. In this work, we capture the fundamental characteristics of the corresponding complex pattern of arm motion by a sculling profile, involving a fast power stroke and a slow recovery stroke. We investigate the propulsive capabilities of a multi-arm robotic system under various swimming gaits, namely patterns of arm coordination, which achieve the generation of forward, as well as backward, propulsion and turning. A lumped-element model of the robotic swimmer, which considers arm compliance and the interaction with the aquatic environment, was used to study the characteristics of these gaits, the effect of various kinematic parameters on propulsion, and the generation of complex trajectories. This investigation focuses on relatively high-stiffness arms. Experiments employing a compliant-body robotic prototype swimmer with eight compliant arms, all made of polyurethane, inside a water tank, successfully demonstrated this novel mode of underwater propulsion. Speeds of up to 0.26 body lengths per second (approximately 100 mm s(-1)), and propulsive forces of up to 3.5 N were achieved, with a non-dimensional cost of transport of 1.42 with all eight arms and of 0.9 with only two active arms. The experiments confirmed the computational results and verified the multi-arm maneuverability and simultaneous object grasping capability of such systems.

Dynamic optimization of a biped model: Energetic walking gaits with different mechanical and gait parameters

Directory of Open Access Journals (Sweden)

Kang An

2015-05-01

Full Text Available Energy consumption is one of the problems for bipedal robots walking. For the purpose of studying the parameter effects on the design of energetic walking bipeds with strong adaptability, we use a dynamic optimization method on our new walking model to first investigate the effects of the mechanical parameters, including mass and length distribution, on the walking efficiency. Then, we study the energetic walking gait features with the combinations of walking speed and step length. Our walking model is designed upon Srinivasan’s model. Dynamic optimization is used for a free search with minimal constraints. The results show that the cost of transport of a certain gait increases with the increase in the mass and length distribution parameters, except for that the cost of transport decreases with big length distribution parameter and long step length. We can also find a corresponding range of walking speed and step length, in which the variation in one of the two parameters has no obvious effect on the cost of transport. With fixed mechanical parameters, the cost of transport increases with the increase in the walking speed. There is a speed–step length relationship for walking with minimal cost of transport. The hip torque output strategy is adjusted in two situations to meet the walking requirements.

A method to standardize gait and balance variables for gait velocity.

NARCIS (Netherlands)

Iersel, M.B. van; Olde Rikkert, M.G.M.; Borm, G.F.

2007-01-01

Many gait and balance variables depend on gait velocity, which seriously hinders the interpretation of gait and balance data derived from walks at different velocities. However, as far as we know there is no widely accepted method to correct for effects of gait velocity on other gait and balance

Advances in robot kinematics

CERN Document Server

Khatib, Oussama

2014-01-01

The topics addressed in this book cover the whole range of kinematic analysis, synthesis and design and consider robotic systems possessing serial, parallel and cable driven mechanisms. The robotic systems range from being less than fully mobile to kinematically redundant to overconstrained.  The fifty-six contributions report the latest results in robot kinematics with emphasis on emerging areas such as design and control of humanoids or humanoid subsystems. The book is of interest to researchers wanting to bring their knowledge up to date regarding modern topics in one of the basic disciplines in robotics, which relates to the essential property of robots, the motion of mechanisms.

A functional comparison of conventional knee-ankle-foot orthoses and a microprocessor-controlled leg orthosis system based on biomechanical parameters.

Science.gov (United States)

Schmalz, Thomas; Pröbsting, Eva; Auberger, Roland; Siewert, Gordon

2016-04-01

The microprocessor-controlled leg orthosis C-Brace enables patients with paretic or paralysed lower limb muscles to use dampened knee flexion under weight-bearing and speed-adapted control of the swing phase. The objective of the present study was to investigate the new technical functions of the C-Brace orthosis, based on biomechanical parameters. The study enrolled six patients. The C-Brace orthosis is compared with conventional leg orthoses (four stance control orthoses, two locked knee-ankle-foot orthoses) using biomechanical parameters of level walking, descending ramps and descending stairs. Ground reaction forces, joint moments and kinematic parameters were measured for level walking as well as ascending and descending ramps and stairs. With the C-Brace, a nearly natural stance phase knee flexion was measured during level walking (mean value 11° ± 5.6°). The maximum swing phase knee flexion angle of the C-Brace approached the normal value of 65° more closely than the stance control orthoses (66° ± 8.5° vs 74° ± 6.4°). No significant differences in the joint moments were found between the C-Brace and stance control orthosis conditions. In contrast to the conventional orthoses, all patients were able to ambulate ramps and stairs using a step-over-step technique with C-Brace (flexion angle 64.6° ± 8.2° and 70.5° ± 12.4°). The results show that the functions of the C-Brace for situation-dependent knee flexion under weight bearing have been used by patients with a high level of confidence. The functional benefits of the C-Brace in comparison with the conventional orthotic mechanisms could be demonstrated most clearly for descending ramps and stairs. The C-Brace orthosis is able to combine improved orthotic function with sustained orthotic safety. © The International Society for Prosthetics and Orthotics 2014.

Gait alterations can reduce the risk of edge loading.

Science.gov (United States)

Wesseling, Mariska; Meyer, Christophe; De Groote, Friedl; Corten, Kristoff; Simon, Jean-Pierre; Desloovere, Kaat; Jonkers, Ilse

2016-06-01

Following metal-on-metal hip arthroplasty, edge loading (i.e., loading near the edge of a prosthesis cup) can increase wear and lead to early revision. The position and coverage angle of the prosthesis cup influence the risk of edge loading. This study investigates the effect of altered gait patterns, more specific hip, and pelvis kinematics, on the orientation of hip contact force and the consequent risk of antero-superior edge loading using muscle driven simulations of gait. With a cup orientation of 25° anteversion and 50° inclination and a coverage angle of 168°, many gait patterns presented risk of edge loading. Specifically at terminal double support, 189 out of 405 gait patterns indicated a risk of edge loading. At this time instant, the high hip contact forces and the proximity of the hip contact force to the edge of the cup indicated the likelihood of the occurrence of edge loading. Although the cup position contributed most to edge loading, altering kinematics considerably influenced the risk of edge loading. Increased hip abduction, resulting in decreasing hip contact force magnitude, and decreased hip extension, resulting in decreased risk on edge loading, are gait strategies that could prevent edge loading. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1069-1076, 2016. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Reliable sagittal plane kinematic gait assessments are feasible using low-cost webcam technology.

Science.gov (United States)

Saner, Robert J; Washabaugh, Edward P; Krishnan, Chandramouli

2017-07-01

Three-dimensional (3-D) motion capture systems are commonly used for gait analysis because they provide reliable and accurate measurements. However, the downside of this approach is that it is expensive and requires technical expertise; thus making it less feasible in the clinic. To address this limitation, we recently developed and validated (using a high-precision walking robot) a low-cost, two-dimensional (2-D) real-time motion tracking approach using a simple webcam and LabVIEW Vision Assistant. The purpose of this study was to establish the repeatability and minimal detectable change values of hip and knee sagittal plane gait kinematics recorded using this system. Twenty-one healthy subjects underwent two kinematic assessments while walking on a treadmill at a range of gait velocities. Intraclass correlation coefficients (ICC) and minimal detectable change (MDC) values were calculated for commonly used hip and knee kinematic parameters to demonstrate the reliability of the system. Additionally, Bland-Altman plots were generated to examine the agreement between the measurements recorded on two different days. The system demonstrated good to excellent reliability (ICC>0.75) for all the gait parameters tested on this study. The MDC values were typically low (gait assessments using webcam technology can be reliably used for clinical and research purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

Design and Evaluation of the LOPES Exoskeleton Robot for Interactive Gait Rehabilitation

NARCIS (Netherlands)

Veneman, J.F.; Kruidhof, R.; Hekman, Edsko E.G.; Ekkelenkamp, R.; van Asseldonk, Edwin H.F.; van der Kooij, Herman

2007-01-01

This paper introduces a newly developed gait rehabilitation device. The device, called LOPES, combines a freely translatable and 2-D-actuated pelvis segment with a leg exoskeleton containing three actuated rotational joints: two at the hip and one at the knee. The joints are impedance controlled to

Evaluación experimental del caminado en tiempo real de un robot bípedo de 5 g.d.l. con marcha basada en movimientos cicloidales

Directory of Open Access Journals (Sweden)

Víctor De-León-Gómez

2015-10-01

Full Text Available Resumen: En este artículo se presentan los resultados de las pruebas de caminado realizadas con el robot bípedo de 5 grados de libertad (g.d.l. desarrollado en el Instituto Tecnológico de la Laguna (ITLag. El patrón de marcha que se aplica en este robot se basa en leyes de movimiento de tipo cicloidal, las cuales le permiten avanzar mediante pasos sin impactos. Los experimentos realizados mostraron un adecuado comportamiento mecánico del robot y un desempeño eficaz de la ley de control aplicada para mantener el ZMP (acrónimo de Zero Moment Point dentro del polígono de soporte de los pies del robot durante la marcha. Los parámetros especificados para el patrón de marcha aseguraron un caminado estable del robot, sin saturar los pares demandados a los actuadores. Abstract: The results of experimental tests of walking of the 5 degrees of freedom (dof biped robot developed at the Instituto Tecnológico de la Laguna (ITLag are presented in this paper. The gait pattern that is applied in this robot is based on cycloidal motion-type laws, which allow to advance by steps without impacts. Experiments showed an adequate mechanical behavior of the robot and effective performance of the control law applied to keep the ZMP (Zero Moment Point inside of the support polygon of the robot's feet during walking. The specified parameters for gait pattern ensured a stable walking of the robot, without saturating the torque applied by the actuators. Palabras clave: Robots bípedos, patrones de marcha, ZMP, movimiento cicloidal, seguimiento de trayectorias., Keywords: Biped robots, gait patterns, ZMP, cycloidal motion, path tracking.

A family of nonlinear PID-like regulators for a class of torque-driven robot manipulators equipped with torque-constrained actuators

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Adriana Salinas

2016-02-01

Full Text Available This article addresses the joint position control of torque-driven robot manipulators under actuators subject to torque saturation. Robots having viscous friction, but without gravity vector, are considered. By assuming a static model for the torque actuator (specifically, a model of nonlinear and non-differentiable hard saturation function, a family of nonlinear proportional–integral–derivative-like controllers is proposed. Lyapunov stability theory is used to establish conditions for local asymptotic stability of the closed-loop system. A notable feature of the proposed controller is that stability conditions do not depend on the saturation levels of the actuators. In addition, an experimental study complements the proposed theory.

A locust-inspired miniature jumping robot.

Science.gov (United States)

Zaitsev, Valentin; Gvirsman, Omer; Ben Hanan, Uri; Weiss, Avi; Ayali, Amir; Kosa, Gabor

2015-11-25

Unmanned ground vehicles are mostly wheeled, tracked, or legged. These locomotion mechanisms have a limited ability to traverse rough terrain and obstacles that are higher than the robot's center of mass. In order to improve the mobility of small robots it is necessary to expand the variety of their motion gaits. Jumping is one of nature's solutions to the challenge of mobility in difficult terrain. The desert locust is the model for the presented bio-inspired design of a jumping mechanism for a small mobile robot. The basic mechanism is similar to that of the semilunar process in the hind legs of the locust, and is based on the cocking of a torsional spring by wrapping a tendon-like wire around the shaft of a miniature motor. In this study we present the jumping mechanism design, and the manufacturing and performance analysis of two demonstrator prototypes. The most advanced jumping robot demonstrator is power autonomous, weighs 23 gr, and is capable of jumping to a height of 3.35 m, covering a distance of 1.37 m.

The Effects of Varying Ankle Foot Orthosis Stiffness on Gait in Children with Spastic Cerebral Palsy Who Walk with Excessive Knee Flexion

NARCIS (Netherlands)

Kerkum, Yvette L.; Buizer, Annemieke I.; van den Noort, Josien C.; Becher, Jules G.; Harlaar, Jaap; Brehm, Merel-Anne

2015-01-01

Rigid Ankle-Foot Orthoses (AFOs) are commonly prescribed to counteract excessive knee flexion during the stance phase of gait in children with cerebral palsy (CP). While rigid AFOs may normalize knee kinematics and kinetics effectively, it has the disadvantage of impeding push-off power. A

The Effects of Varying Ankle Foot Orthosis Stiffness on Gait in Children with Spastic Cerebral Palsy Who Walk with Excessive Knee Flexion

NARCIS (Netherlands)

Kerkum, Y.L.; Buizer, A.I.; van den Noort, J.C.; Becher, J.G.; Harlaar, J.; Brehm, M.A.

2015-01-01

Introduction: Rigid Ankle-Foot Orthoses (AFOs) are commonly prescribed to counteract excessive knee flexion during the stance phase of gait in children with cerebral palsy (CP). While rigid AFOs may normalize knee kinematics and kinetics effectively, it has the disadvantage of impeding push-off

Kinematic Analysis of Continuum Robot Consisted of Driven Flexible Rods

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Yingzhong Tian

2016-01-01

Full Text Available This paper presents the kinematic analysis of a continuum bionic robot with three flexible actuation rods. Since the motion of the end-effector is actuated by the deformation of the rods, the robot structure is with high elasticity and good compliance and the kinematic analysis of the robot requires special treatment. We propose a kinematic model based on the geometry with constant curvature. The analysis consists of two independent mappings: a general mapping for the kinematics of all robots and a specific mapping for this kind of robots. Both of those mappings are developed for the single section and for the multisections. We aim at providing a guide for kinematic analysis of the similar manipulators through this paper.

An Orientation Sensor for Mobile Robots Using Differentials

Directory of Open Access Journals (Sweden)

Wei-Chen Lee

2013-02-01

Full Text Available Without access to external guidance, such as landmarks or beacons, indoor mobile robots usually orientate themselves by using magnetic compasses or gyroscopes. However, compasses face interference from steel furniture, and gyroscopes suffer from zero drift errors. This paper proposes an orientation sensor that can be used on differentially driven mobile robots to resolve these issues. The sensor innovatively combines the general differentials and an optical encoder so that it can provide only the orientation information. Such a sensor has not been described in any known literature and is cost-efficient compared to the common method of using two encoders for differentially driven mobile robots. The kinematic analysis and the mechanical design of this sensor are presented in this paper. The maximum mean error of the proposed orientation sensor was about 0.7° during the component tests. The application of the sensor on a vacuum cleaning robot was also demonstrated. The use of the proposed sensor may provide less uncertain orientation data for an indoor differentially driven mobile robot.

Biologically-Inspired Microrobots. Volume 3. Micro-Robot Based on Abstracted Biological Principles

National Research Council Canada - National Science Library

Quinn, Roger D; Ritzmann, Roy E; Morrey, Jeremy; Horchler, Andrew

2006-01-01

.... Mini-Whegs use four wheel-legs to run in an alternating diagonal gait. These approximately 3-inch-long robots can move at sustained speeds of over 10 body lengths per second and can run over obstacles that are taller than their leg length...

Gait adjustments in obstacle crossing, gait initiation and gait termination after a recent lower limb amputation

NARCIS (Netherlands)

Vrieling, Aline H.; van Keeken, Helco G.; Schoppen, Tanneke; Hof, At L.; Otten, Bert; Halbertsma, Jan P. K.; Postema, Klaas

Objective: To describe the adjustments in gait characteristics of obstacle crossing, gait initiation and gait termination that occur in subjects with a recent lower limb amputation during the rehabilitation process. Design: Prospective and descriptive study. Subjects: Fourteen subjects with a recent

Characteristics of the muscle activities of the elderly for various pressures in the pneumatic actuator of lower limb orthosis

Science.gov (United States)

Kim, Kyong; Yu, Chang-Ho; Kwon, Tae-Kyu; Hong, Chul-Un; Kim, Nam-Gyun

2005-12-01

There developed a lower limb orthosis with a pneumatic rubber actuator, which can assist and improve the muscular activities in the lower limb of the elderly. For this purpose, the characteristics of the lower limbs muscle activities for various pressures in the pneumatic actuator for the lower limb orthosis was investigated. To find out the characteristics of the muscle activities for various pneumatic pressures, it analyzed the flexing and extending movement of the knees, and measured the lower limbs muscular power. The subjects wearing the lower limbs orthosis were instructed to perform flexing and extending movement of the knees. The variation in the air pressure of the pneumatic actuator was varies from one kgf/cm2 to four kgf/cm2. The muscular power was measured by monitoring electromyogram using MP100 (BIOPAC Systems, Inc.) and detailed three-dimensional motions of the lower limbs were collected by APAS 3D Motion Analysis system. Through this study, it expected to find the most suitable air pressure for the improvement of the muscular power of the aged.

Robot-Assisted Training Early After Cardiac Surgery.

Science.gov (United States)

Schoenrath, Felix; Markendorf, Susanne; Brauchlin, Andreas E; Seifert, Burkhardt; Wilhelm, Markus J; Czerny, Martin; Riener, Robert; Falk, Volkmar; Schmied, Christian M

2015-07-01

To assess feasibility and safety of a robot-assisted gait therapy with the Lokomat® system in patients early after open heart surgery. Within days after open heart surgery 10 patients were subjected to postoperative Lokomat® training (Intervention group, IG) whereas 20 patients served as controls undergoing standard postoperative physiotherapy (Control group, CG). All patients underwent six-minute walk test and evaluation of the muscular strength of the lower limbs by measuring quadriceps peak force. The primary safety end-point was freedom from any device-related wound healing disturbance. Patients underwent clinical follow-up after one month. Both training methods resulted in an improvement of walking distance (IG [median, interquartile range, p-value]: +119 m, 70-201 m, p = 0.005; CG: 105 m, 57-152.5m, p force (IG left: +5 N, 3.8 7 N, p = 0.005; IG right: +3.5 N, 1.5-8.8 N, p = 0.011; CG left: +5.5 N, 4-9 N, p training were comparable to early postoperative standard in hospital training (median changes in walking distance in percent, p = 0.81; median changes in quadriceps peak force in percent, left: p = 0.97, right p = 0.61). No deep sternal wound infection or any adverse event occurred in the robot-assisted training group. Robot-assisted gait therapy with the Lokomat® system is feasible and safe in patients early after median sternotomy. Results with robot-assisted training were comparable to standard in hospital training. An adapted and combined aerobic and resistance training intervention with augmented feedback may result in benefits in walking distance and lower limb muscle strength (ClinicalTrials.gov number, NCT 02146196). © 2015 Wiley Periodicals, Inc.

A brain-controlled lower-limb exoskeleton for human gait training

Science.gov (United States)

Liu, Dong; Chen, Weihai; Pei, Zhongcai; Wang, Jianhua

2017-10-01

Brain-computer interfaces have been a novel approach to translate human intentions into movement commands in robotic systems. This paper describes an electroencephalogram-based brain-controlled lower-limb exoskeleton for gait training, as a proof of concept towards rehabilitation with human-in-the-loop. Instead of using conventional single electroencephalography correlates, e.g., evoked P300 or spontaneous motor imagery, we propose a novel framework integrated two asynchronous signal modalities, i.e., sensorimotor rhythms (SMRs) and movement-related cortical potentials (MRCPs). We executed experiments in a biologically inspired and customized lower-limb exoskeleton where subjects (N = 6) actively controlled the robot using their brain signals. Each subject performed three consecutive sessions composed of offline training, online visual feedback testing, and online robot-control recordings. Post hoc evaluations were conducted including mental workload assessment, feature analysis, and statistics test. An average robot-control accuracy of 80.16% ± 5.44% was obtained with the SMR-based method, while estimation using the MRCP-based method yielded an average performance of 68.62% ± 8.55%. The experimental results showed the feasibility of the proposed framework with all subjects successfully controlled the exoskeleton. The current paradigm could be further extended to paraplegic patients in clinical trials.

Guillain-Barre Syndrome – rehabilitation outcome, residual deficits and requirement of lower limb orthosis for locomotion at 1 year follow-up.

Science.gov (United States)

Gupta, Anupam; Taly, Arun B; Srivastava, Abhishek; Murali, Thyloth

2010-01-01

To analyse long-term functional recovery, deficits and requirement of lower limb orthosis (LLO) for locomotion in patients with Guillain-Barre Syndrome (GBS). Prospective longitudinal follow-up study. Neurological Rehabilitation unit of university hospital. Sixty-nine patients of GBS admitted for inpatient rehabilitation. Thirty-five patients (M:F, 19:16) reporting after 1 year follow-up (50.72%) were included in study (between September 2005 and July 2009). Their residual deficits and requirement of LLO were recorded and analysed. Age ranged from 4 to 65 year (29.74 ± 15.75). Twenty-seven patients had typical GBS and eight patients had acute motor axonal neuropathy variant. Twenty-eight patients (80%) had neuropathic pain needing medication with 11 required more than one drug. Twenty-one patients (60%) had foot drop and advised ankle-foot orthosis-AFO (20 bilateral AFO). Thirty patients (85.71%) needed assistive devices also for locomotion at discharge. After 1 year, foot drop was still present in 12 patients (34.28%) using orthosis. Modified Barthel Index scores, Modified Rankin Scale and Hughes Disability Scale were used to assess functional disabilities. Significant recovery was observed at the time of discharge and after 1 year (p < 0.001 each). Patients with GBS continue to show significant functional recovery for long period. They have residual deficits even after 1 year with requirement of orthosis in large number of patients.

Sensory feedback plays a significant role in generating walking gait and in gait transition in salamanders: A simulation study

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Nalin eHarischandra

2011-11-01

Full Text Available Here, we use a three-dimensional, neuro-musculo-mechanical model of a salamander with realistic physical parameters in order to investigate the role of sensory feedback in gait generation and transition. Activation of limb and axial muscles were driven by neural output patterns obtained from a central pattern generator (CPG which is composed of simulated spiking neurons with adaptation. The CPG consists of a body CPG and four limb CPGs that are interconnected via synapses both ipsilateraly and contralaterally. We use the model both with and without sensory modulation and for different combinations of ipsilateral and contralateral coupling between the limb CPGs. We found that the proprioceptive sensory inputs are essential in obtaining a coordinated walking gait. The sensory feedback includes the signals coming from the stretch receptor like intraspinal neurons located in the girdle regions and the limb stretch receptors residing in the hip and scapula regions of the salamander. On the other hand, coordinated motor output patterns for the trotting gait were obtainable without the sensory inputs. We found that the gait transition from walking to trotting can be induced by increased activity of the descending drive coming from the mesencephalic locomotor region (MLR and is helped by the sensory inputs at the hip and scapula regions detecting the late stance phase. More neurophysiological experiments are required to identify the precise type of mechanoreceptors in the salamander and the neural mechanisms mediating the sensory modulation.

Robot-assisted walking with the Lokomat: the influence of different levels of guidance force on thorax and pelvis kinematics.

Science.gov (United States)

Swinnen, Eva; Baeyens, Jean-Pierre; Knaepen, Kristel; Michielsen, Marc; Clijsen, Ron; Beckwée, David; Kerckhofs, Eric

2015-03-01

Little attention has been devoted to the thorax and pelvis movements during gait. The aim of this study is to compare differences in the thorax and pelvis kinematics during unassisted walking on a treadmill and during walking with robot assistance (Lokomat-system (Hocoma, Volketswil, Switzerland)). 18 healthy persons walked on a treadmill with and without the Lokomat system at 2kmph. Three different conditions of guidance force (30%, 60% and 100%) were used during robot-assisted treadmill walking (30% body weight support). The maximal movement amplitudes of the thorax and pelvis were measured (Polhemus Liberty™ (Polhemus, Colchester, Vermont, USA) (240/16)). A repeated measurement ANOVA was conducted. Robot-assisted treadmill walking with different levels of guidance force showed significantly smaller maximal movement amplitudes for thorax and pelvis, compared to treadmill walking. Only the antero-posterior tilting of the pelvis was significantly increased during robot-assisted treadmill walking compared to treadmill walking. No significant changes of kinematic parameters were found between the different levels of guidance force. With regard to the thorax and pelvis movements, robot-assisted treadmill walking is significantly different compared to treadmill walking. It can be concluded that when using robot assistance, the thorax is stimulated in a different way than during walking without robot assistance, influencing the balance training during gait. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of Rocker Bar Ankle Foot Orthosis on Functional Mobility in Post-Stroke Hemiplegic Patients: Timed Up and Go and Gait Speed Assessments

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Farzad Farmani

2016-03-01

Discussion: RAFO led to a significant improvement in functional mobility in hemiplegic patients post stroke. This may be due to the positive effect of rocker modification on improving push off and transferring weight during the stance phase of gait.

Robot Wars: US Empire and geopolitics in the robotic age

Science.gov (United States)

Shaw, Ian GR

2017-01-01

How will the robot age transform warfare? What geopolitical futures are being imagined by the US military? This article constructs a robotic futurology to examine these crucial questions. Its central concern is how robots – driven by leaps in artificial intelligence and swarming – are rewiring the spaces and logics of US empire, warfare, and geopolitics. The article begins by building a more-than-human geopolitics to de-center the role of humans in conflict and foreground a worldly understanding of robots. The article then analyzes the idea of US empire, before speculating upon how and why robots are materializing new forms of proxy war. A three-part examination of the shifting spaces of US empire then follows: (1) Swarm Wars explores the implications of miniaturized drone swarming; (2) Roboworld investigates how robots are changing US military basing strategy and producing new topological spaces of violence; and (3) The Autogenic Battle-Site reveals how autonomous robots will produce emergent, technologically event-ful sites of security and violence – revolutionizing the battlespace. The conclusion reflects on the rise of a robotic US empire and its consequences for democracy. PMID:29081605

Comparison of energy efficiency between Wearable Power-Assist Locomotor (WPAL) and two types of knee-ankle-foot orthoses with a medial single hip joint (MSH-KAFO).

Science.gov (United States)

Yatsuya, Kanan; Hirano, Satoshi; Saitoh, Eiichi; Tanabe, Shigeo; Tanaka, Hirotaka; Eguchi, Masayuki; Katoh, Masaki; Shimizu, Yasuhiro; Uno, Akito; Kagaya, Hitoshi

2018-01-01

To compare the energy efficiency of Wearable Power-Assist Locomotor (WPAL) with conventional knee-ankle-foot orthoses (MSH-KAFO) such as Hip and Ankle Linked Orthosis (HALO) or Primewalk. Cross over case-series. Chubu Rosai Hospital, Aichi, Japan, which is affiliated with the Japan Organization of Occupational Health and Safety. Six patients were trained with MSH-KAFO (either HALO or Primewalk) and WPAL. They underwent 6-minute walk tests with each orthosis. Energy efficiency was estimated using physiological cost index (PCI) as well as heart rate (HR) and modified Borg score. Trial energy efficiency with MSH-KAFO was compared with WPAL to assess if differences in PCI became greater between MSH-KAFO and WPAL as time goes on during the 6-minute walk. Spearman correlation coefficient of time (range: 0.5-6.0 minutes) with the difference was calculated. The same statistical procedures were repeated for HR and modified Borg score. Greater energy efficiency, representing a lower gait demand, was observed in trials with WPAL compared with MSH-KAFO (Spearman correlation coefficients for PCI, HR and modified Borg were 0.93, 0.90 and 0.97, respectively, all P energy efficient type of robotics that may be used by patients with paraplegia.

Optical Robotics in Mesoscopia

DEFF Research Database (Denmark)

Glückstad, Jesper

2012-01-01

With light’s miniscule momentum, shrinking robotics down to the micro-scale regime creates opportunities for exploiting optical forces and torques in advanced actuation and control at the nano- and micro-scale dimensions. Advancing light-driven nano- or micro-robotics requires the optimization...... of optimized shapes in the micro-robotics structures [1]. We designed different three-dimensional microstructures and had them fabricated by two-photon polymerization at BRC Hungary. These microstructures were then handled by our proprietary BioPhotonics Workstation to show proof-of-principle 3 demonstrations...

GaitKeeper: A System for Measuring Canine Gait

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Cassim Ladha

2017-02-01

Full Text Available It is understood gait has the potential to be used as a window into neurodegenerative disorders, identify markers of subclinical pathology, inform diagnostic algorithms of disease progression and measure the efficacy of interventions. Dogs’ gaits are frequently assessed in a veterinary setting to detect signs of lameness. Despite this, a reliable, affordable and objective method to assess lameness in dogs is lacking. Most described canine lameness assessments are subjective, unvalidated and at high risk of bias. This means reliable, early detection of canine gait abnormalities is challenging, which may have detrimental implications for dogs’ welfare. In this paper, we draw from approaches and technologies used in human movement science and describe a system for objectively measuring temporal gait characteristics in dogs (step-time, swing-time, stance-time. Asymmetries and variabilities in these characteristics are of known clinical significance when assessing lameness but presently may only be assessed on coarse scales or under highly instrumented environments. The system consists an inertial measurement unit, containing a 3-axis accelerometer and gyroscope coupled with a standardized walking course. The measurement unit is attached to each leg of the dog under assessment before it is walked around the course. The data by the measurement unit is then processed to identify steps and subsequently, micro-gait characteristics. This method has been tested on a cohort of 19 healthy dogs of various breeds ranging in height from 34.2 cm to 84.9 cm. We report the system as capable of making precise step delineations with detections of initial and final contact times of foot-to-floor to a mean precision of 0.011 s and 0.048 s, respectively. Results are based on analysis of 12,678 foot falls and we report a sensitivity, positive predictive value and F-score of 0.81, 0.83 and 0.82 respectively. To investigate the effect of gait on system performance

ROBOTICS APPLICATION IN PEOPLE WITH WEAK MUSCLES – STANDING AND WALKING

Directory of Open Access Journals (Sweden)

Zlatko Matjačić

2004-12-01

Full Text Available In this review paper we provide brief information on three commercially available biomechatronic devices that were primarily developed for neurological rehabilitation after stroke and spinal cord injury. First, we present Balance Trainer, a biomechatronic device that enables safe standing and balancing environment where the level of balancing support can be varied according to a particular subject’s needs. Gait Trainer and Locomat are biomechatronic/robotic devices that enable repetitive practice of gait-like movement in non-ambulatory subjects. We briefly discuss potential application of the presented devices for therapeutical purposes in people with muscular distrophy.

Morphological self stabilization of locomotion gaits: illustration on a few examples from bio-inspired locomotion.

Science.gov (United States)

Chevallereau, Christine; Boyer, Frédéric; Porez, Mathieu; Mauny, Johan; Aoustin, Yannick

2017-06-20

To a large extent, robotics locomotion can be viewed as cyclic motions, named gaits. Due to the high complexity of the locomotion dynamics, to find the control laws that ensure an expected gait and its stability with respect to external perturbations, is a challenging issue for feedback control. To address this issue, a promising way is to take inspiration from animals that intensively exploit the interactions of the passive degrees of freedom of their body with their physical surroundings, to outsource the high-level exteroceptive feedback control to low-level proprioceptive ones. In this case, passive interactions can ensure most of the expected control goals. In this article, we propose a methodological framework to study the role of morphology in the design of locomotion gaits and their stability. This framework ranges from modelling to control aspects, and is illustrated through three examples from bio-inspired locomotion: a three-dimensional micro air vehicle in hovering flight, a pendular planar climber and a bipedal planar walker. In these three cases, we will see how simple considerations based on the morphology of the body can ensure the existence of passive stable gaits without requiring any high-level control.

A COMPARATIVE STUDY TO FIND OUT IMMEDIATE EFFECTIVENESS OF MOVEMENT WITH MOBILIZATION VERSUS ELBOW ORTHOSIS ON PAIN AND GRIP STRENGTH IN LATERAL EPICONDYLITIS IN HOUSEWIVES

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Trishna Kakati

2015-12-01

Full Text Available Background: There are various studies using Mulligan’s MWM with or without combining with electrotherapy modalities and proved the efficacy of the technique in immediately decreasing pain and improving grip strength in patients with lateral epicondylitis. Orthotic as a treatment is also proved to be beneficial in decreasing pain and improving grip strength. There is evidence that housewives are prone to develop lateral epicondylitis due to their routine household work. But there is lack of evidence which compare initial effects of MWM and orthosis in housewives bringing up better outcome measures. The purpose of this study is to compare the initial effectiveness of Mulligan’s MWM and elbow orthosis on pain and grip strength in housewives with lateral epicondylitis. The aim of the study is to evaluate the effectiveness of Mulligan’s MWM technique versus counterforce elbow orthosis in immediately reducing pain and improving grip strength in lateral epicondylitis in housewives. Methodos: All subjects underwent a pre-treatment examination to assess pain and pain free hand grip strength with the help of outcome measures. Subjects were randomly assigned into two groups, A and B respectively; having 25 subjects in each group. Group A was treated with one session of Mulligan’s MWM technique. Group B was treated with Counterforce elbow strap orthosis. Data was assessed pre-treatment and immediately after treatment. Visual Analogue Scale (VAS and hand grip on Hand Grip Dynamometer (HGD were used as outcome measures. Results: Independent t-test was performed to see the effectiveness between Mulligan’s MWM and elbow orthosis. For VAS, t = - 2.243 which is significant at 5% level of significance. It has been inferred that VAS decreases more when Mulligan’s MWM was applied. For HGD, t = 0.878 which is not significant implying that increase in HGD do not differ remarkably for the two treatments. Conclusion: It has been recorded from the study that

Muscle coordination in healthy subjects during floor walking and stair climbing in robot assisted gait training.

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Hussein, S; Schmidt, H; Volkmar, M; Werner, C; Helmich, I; Piorko, F; Krüger, J; Hesse, S

2008-01-01

The aim of gait rehabilitation is a restoration of an independent gait and improvement of daily life walking functions. Therefore the specific patterns, that are to be relearned, must be practiced to stimulate the learning process of the central nervous system (CNS). The Walking Simulator HapticWalker allows for the training of arbitrary gait trajectories of daily life. To evaluate the quality of the training a total of 9 subjects were investigated during free floor walking and stair climbing and during the same tasks in two different training modes on the HapticWalker: 1) with and 2) without vertical center of mass (CoM) motion. Electromyograms (EMG) of 8 gait relevant muscles were measured and muscle activation was compared for the various training modes. Besides the muscle activation as an indicator for the quality of rehabilitation training the study investigates if a cancellation of the vertical CoM movement by adaption of the footplate trajectory is feasible i.e. the muscle activation patterns for the two training modes on the HapticWalker agree. Results show no significant differences in activation timing between the training modes. This indicates the feasibility of using a passive patient suspension and emulate the vertical CoM motion by trajectory adaption of the footplates. The muscle activation timing during HapticWalker training shows important characteristics observed in physiological free walking though a few differences can still remain.

Monitoring a robot swarm using a data-driven fault detection approach

KAUST Repository

Khaldi, Belkacem; Harrou, Fouzi; Cherif, Foudil; Sun, Ying

2017-01-01

Using swarm robotics system, with one or more faulty robots, to accomplish specific tasks may lead to degradation in performances complying with the target requirements. In such circumstances, robot swarms require continuous monitoring to detect

Comparison of the Classifier Oriented Gait Score and the Gait Profile Score based on imitated gait impairments.

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Christian, Josef; Kröll, Josef; Schwameder, Hermann

2017-06-01

Common summary measures of gait quality such as the Gait Profile Score (GPS) are based on the principle of measuring a distance from the mean pattern of a healthy reference group in a gait pattern vector space. The recently introduced Classifier Oriented Gait Score (COGS) is a pathology specific score that measures this distance in a unique direction, which is indicated by a linear classifier. This approach has potentially improved the discriminatory power to detect subtle changes in gait patterns but does not incorporate a profile of interpretable sub-scores like the GPS. The main aims of this study were to extend the COGS by decomposing it into interpretable sub-scores as realized in the GPS and to compare the discriminative power of the GPS and COGS. Two types of gait impairments were imitated to enable a high level of control of the gait patterns. Imitated impairments were realized by restricting knee extension and inducing leg length discrepancy. The results showed increased discriminatory power of the COGS for differentiating diverse levels of impairment. Comparison of the GPS and COGS sub-scores and their ability to indicate changes in specific variables supports the validity of both scores. The COGS is an overall measure of gait quality with increased power to detect subtle changes in gait patterns and might be well suited for tracing the effect of a therapeutic treatment over time. The newly introduced sub-scores improved the interpretability of the COGS, which is helpful for practical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Walking with robot assistance: the influence of body weight support on the trunk and pelvis kinematics.

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Swinnen, Eva; Baeyens, Jean-Pierre; Knaepen, Kristel; Michielsen, Marc; Hens, Gerrit; Clijsen, Ron; Goossens, Maggie; Buyl, Ronald; Meeusen, Romain; Kerckhofs, Eric

2015-05-01

The goal was to assess in healthy participants the three-dimensional kinematics of the pelvis and the trunk during robot-assisted treadmill walking (RATW) at 0%, 30% and 50% body weight support (BWS), compared with treadmill walking (TW). 18 healthy participants walked (2 kmph) on a treadmill with and without robot assistance (Lokomat; 60% guidance force; 0%, 30% and 50% BWS). After an acclimatisation period (four minutes), trunk and pelvis kinematics were registered in each condition (Polhemus Liberty [240 Hz]). The results were analysed using a repeated measures analysis of variance with Bonferroni correction, with the level of suspension as within-subject factor. During RATW with BWS, there were significantly (1) smaller antero-posterior and lateral translations of the trunk and the pelvis; (2) smaller antero-posterior flexion and axial rotation of the trunk; (3) larger lateral flexion of the trunk; and (4) larger antero-posterior tilting of the pelvis compared with TW. There are significant differences in trunk and pelvis kinematics in healthy persons during TW with and without robot assistance. These data are relevant in gait rehabilitation, relating to normal balance regulation. Additional research is recommended to further assess the influence of robot assistance on human gait. The trunk and pelvis moves in a different way during walking with robot assistance. The data suggest that the change in movement is due to the robot device and the harness of the suspension system more than due to the level of suspension itself.