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Sample records for sub-maximal wheelchair propulsion

  1. Wheelchair propulsion biomechanics: implications for wheelchair sports.

    Science.gov (United States)

    Vanlandewijck, Y; Theisen, D; Daly, D

    2001-01-01

    The aim of this article is to provide the reader with a state-of-the-art review on biomechanics in hand rim wheelchair propulsion, with special attention to sport-specific implications. Biomechanical studies in wheelchair sports mainly aim at optimising sport performance or preventing sport injuries. The sports performance optimisation question has been approached from an ergonomic, as well as a skill proficiency perspective. Sports medical issues have been addressed in wheelchair sports mainly because of the extremely high prevalence of repetitive strain injuries such as shoulder impingement and carpal tunnel syndrome. Sports performance as well as sports medical reflections are made throughout the review. Insight in the underlying musculoskeletal mechanisms of hand rim wheelchair propulsion has been achieved through a combination of experimental data collection under realistic conditions, with a more fundamental mathematical modelling approach. Through a synchronised analysis of the movement pattern, force generation pattern and muscular activity pattern, insight has been gained in the hand rim wheelchair propulsion dynamics of people with a disability, varying in level of physical activity and functional potential. The limiting environment of a laboratory, however, has hampered the drawing of sound conclusions. Through mathematical modelling, simulation and optimisation (minimising injury and maximising performance), insight in the underlying musculoskeletal mechanisms during wheelchair propulsion is sought. The surplus value of inverse and forward dynamic simulation of hand rim stroke dynamics is addressed. Implications for hand rim wheelchair sports are discussed. Wheelchair racing, basketball and rugby were chosen because of the significance and differences in sport-specific movement dynamics. Conclusions can easily be transferred to other wheelchair sports where movement dynamics are fundamental.

  2. Optimum cycle frequencies in hand-rim wheelchair propulsion. Wheelchair propulsion technique

    NARCIS (Netherlands)

    van der Woude, L H; Veeger, DirkJan (H. E. J.); Rozendal, R H; Sargeant, A J

    1989-01-01

    To study the effect of different cycle frequencies on cardio-respiratory responses and propulsion technique in hand-rim wheelchair propulsion, experienced wheelchair sportsmen (WS group; n = 6) and non-wheelchair users (NW group; n = 6) performed wheelchair exercise tests on a motor-driven

  3. Wrist motion in handrim wheelchair propulsion

    NARCIS (Netherlands)

    Veeger, H E J; Meershoek, L S; van der Woude, L H; Langenhoff, J M

    Prevalence rates of carpal tunnel syndrome (CTS) in the wheelchair user population are high. One of the possible causes of CTS in this population is the movement pattern of the wrist during handrim wheelchair propulsion, which could include large wrist joint angles and wrist/finger flexor activity.

  4. Biomechanics and physiology in handrim wheelchair propulsion

    NARCIS (Netherlands)

    van der Woude, L.H.V.; Veeger, H.E.J.; Dallmeijer, A.J.; Janssen, T.W.J.; Rozendaal, L.A.

    2001-01-01

    Manual wheelchair propulsion in daily life and sports is increasingly being studied. Initially, an engineering and physiological perspective was taken. More recently a concomitant biomechanics interest is seen. Themes of biomechanical and physiological studies today are performance enhancing aspects

  5. A 2-D model of wheelchair propulsion.

    Science.gov (United States)

    Morrow, D A; Guo, L Y; Zhao, K D; Su, F C; An, K N

    To illustrate the potential benefits of kinetic and kinematic models in the exploration of biomechanical studies as illustrated using a simple 2-D static optimization model of wheelchair propulsion. A four-bar linkage analysis was used to determine sagittal plane motion through the range of wheelchair propulsion. Using anthropometric measures of wheelchair users, this analysis determined the angles of shoulder and elbow flexion/extension at a given point in the propulsion cycle. Maximal strength inputs for the model were collected from isokinetic measurements of shoulder and elbow moments. The torque inputs were given as functions of sagittal plane joint angles. Through selection of appropriate model performance criteria, optimization techniques determined shoulder and elbow torque contributions throughout the propulsion cycle. Variations in the model parameters of anterior-posterior (AP) seat position and handrim size went used to show potential of model to evaluate wheelchair configuration using the performance criteria of propulsive moment (Mo) and efficiency as defined by fractional effective force (FEF). The model was able to predict the magnitude and direction of force applied to the handrim from shoulder and elbow moments. These joint moments may be examined along with the generated wheelchair axle propulsion moment. While the model showed no significant changes in either Mo or FEF for AP seat changes, an increase in handrim size was shown to increase FEF. This model was able to simulate wheelchair propulsion and allow for performance analyses. The open nature of the model allowed for tweaking of the kinematic inputs to examine the sensitivity of such factors as seat position and handrim size in wheelchair propulsion. Strength inputs to the model may also be altered to study the potential effects of strength training or muscle weakness.

  6. Is effective force application in handrim wheelchair propulsion also efficient?

    NARCIS (Netherlands)

    Bregman, D.J.J.; van Drongelen, S.V.; Veeger, H.E.J.

    2009-01-01

    Background: Efficiency in manual wheelchair propulsion is low, as is the fraction of the propulsion force that is attributed to the moment of propulsion of the wheelchair. In this study we tested the hypothesis that a tangential propulsion force direction leads to an increase in physiological cost,

  7. Biomechanics and physiology in active manual wheelchair propulsion

    NARCIS (Netherlands)

    van der Woude, L H; Veeger, H E; Dallmeijer, A J; Janssen, T W; Rozendaal, L A

    2001-01-01

    Manual wheelchair propulsion in daily life and sports is increasingly being studied. Initially, an engineering and physiological perspective was taken. More recently a concomitant biomechanics interest is seen. Themes of biomechanical and physiological studies today are performance enhancing aspects

  8. The physiological and biomechanical effects of forwards and reverse sports wheelchair propulsion.

    Science.gov (United States)

    Mason, Barry S; Lenton, John P; Goosey-Tolfrey, Victoria L

    2015-07-01

    To explore the physiological and biomechanical differences between forwards (FOR) and reverse (REV) sports wheelchair propulsion. Fourteen able-bodied males with previous wheelchair propulsion experience pushed a sports wheelchair on a single-roller ergometer in a FOR and REV direction at three sub-maximal speeds (4, 6, and 8 km/hour). Each trial lasted 3 minutes, and during the final minute physiological and biomechanical measures was collected. The physiological results revealed that oxygen uptake (1.51 ± 0.29 vs. 1.38 ± 0.26 L/minute, P = 0.005) and heart rate (121 ± 19 vs. 109 ± 14 beats/minute, P 0.05). However, greater mean resultant forces were applied during FOR (P < 0.0005) at 4 km/hour (66.7 ± 19.5 vs. 49.2 ± 10.3 N), 6 km/hour (90.7 ± 21.9 vs. 65.3 ± 18.6 N), and 8 km/hour (102.5 ± 17.6 vs. 68.7 ± 13.5 N) compared to REV. Alternatively, push times and push angles were significantly lower (P ≤ 0.001) during FOR at each speed. The current study demonstrated that at higher speeds physiological demand becomes elevated during REV. This was likely to be associated with an inability to apply sufficient force to the wheels, thus requiring kinematic adaptations in order to maintain constant speeds in REV.

  9. Arm cranking versus wheelchair propulsion for testing aerobic fitness in children with spina bifida who are wheelchair dependent.

    OpenAIRE

    Bloemen, M.A.T.; Groot, J.F. de; Backx, F.J.G.; Westerveld, R.A.; Takken, T.

    2015-01-01

    Objective: To determine the best test performance and feasibility using a Graded Arm Cranking Test vs a Graded Wheelchair Propulsion Test in young people with spina bifida who use a wheelchair, and to determine the reliability of the best test. Design: Validity and reliability study. Subjects: Young people with spina bifida who use a wheelchair. Methods: Physiological responses were measured during a Graded Arm Cranking Test and a Graded Wheelchair Propulsion Test using a heart rate monitor a...

  10. Exercise training programs to improve hand rim wheelchair propulsion capacity: a systematic review

    NARCIS (Netherlands)

    Zwinkels, M.G.J.; Verschuren, O.W.; Janssen, T.; Ketelaar, M.; Takken, T.; Backx, F.J.G.; Groot, J.F. de; Smits, D.W.; Volman, MJM

    2014-01-01

    Objective: An adequate wheelchair propulsion capacity is required to perform daily life activities. Exercise training may be effective to gain or improve wheelchair propulsion capacity. This review investigates whether different types of exercise training programs are effective in improving

  11. Exercise training programs to improve hand rim wheelchair propulsion capacity: a systematic review.

    NARCIS (Netherlands)

    Zwinkels, M.; Verschuren, O.; Janssen, T.W.J.; Ketelaar, M.; Takken, T.

    2014-01-01

    Objective: An adequate wheelchair propulsion capacity is required to perform daily life activities. Exercise training may be effective to gain or improve wheelchair propulsion capacity. This review investigates whether different types of exercise training programs are effective in improving

  12. Variability in bimanual wheelchair propulsion: Consistency of two instrumented wheels during handrim wheelchair propulsion on a motor driven treadmill

    NARCIS (Netherlands)

    Vegter, R.J.K.; Lamoth, C.J.C.; de Groot, S.; Veeger, H.E.J.; van der Woude, L.H.V.

    2013-01-01

    Background: Handrim wheelchair propulsion is a complex bimanual motor task. The bimanually applied forces on the rims determine the speed and direction of locomotion. Measurements of forces and torques on the handrim are important to study status and change of propulsion technique (and consequently

  13. Variability in bimanual wheelchair propulsion : consistency of two instrumented wheels during handrim wheelchair propulsion on a motor driven treadmill

    NARCIS (Netherlands)

    Vegter, Riemer J. K.; Lamoth, Claudine J.; de Groot, Sonja; Veeger, Dirkjan H. E. J.; van der Woude, Lucas H. V.

    2013-01-01

    Background: Handrim wheelchair propulsion is a complex bimanual motor task. The bimanually applied forces on the rims determine the speed and direction of locomotion. Measurements of forces and torques on the handrim are important to study status and change of propulsion technique (and consequently

  14. Variability in bimanual wheelchair propulsion : Consistency of two instrumented wheels during handrim wheelchair propulsion on a motor driven treadmill

    NARCIS (Netherlands)

    Vegter, R.J.K.; Lamoth, C.J.; De Groot, S.; Veeger, H.E.J.; Van der Woude, L.H.V.

    2013-01-01

    Background Handrim wheelchair propulsion is a complex bimanual motor task. The bimanually applied forces on the rims determine the speed and direction of locomotion. Measurements of forces and torques on the handrim are important to study status and change of propulsion technique (and consequently

  15. Constraints influencing sports wheelchair propulsion performance and injury risk

    Science.gov (United States)

    2013-01-01

    The Paralympic Games are the pinnacle of sport for many athletes with a disability. A potential issue for many wheelchair athletes is how to train hard to maximise performance while also reducing the risk of injuries, particularly to the shoulder due to the accumulation of stress placed on this joint during activities of daily living, training and competition. The overall purpose of this narrative review was to use the constraints-led approach of dynamical systems theory to examine how various constraints acting upon the wheelchair-user interface may alter hand rim wheelchair performance during sporting activities, and to a lesser extent, their injury risk. As we found no studies involving Paralympic athletes that have directly utilised the dynamical systems approach to interpret their data, we have used this approach to select some potential constraints and discussed how they may alter wheelchair performance and/or injury risk. Organism constraints examined included player classifications, wheelchair setup, training and intrinsic injury risk factors. Task constraints examined the influence of velocity and types of locomotion (court sports vs racing) in wheelchair propulsion, while environmental constraints focused on forces that tend to oppose motion such as friction and surface inclination. Finally, the ecological validity of the research studies assessing wheelchair propulsion was critiqued prior to recommendations for practice and future research being given. PMID:23557065

  16. Relation between kinematic analysis of wheelchair propulsion and wheelchair functional basketball classification.

    Science.gov (United States)

    Crespo-Ruiz, Beatriz M; Del Ama-Espinosa, Antonio J; Gil-Agudo, Angel M

    2011-04-01

    The objective was to conduct a methodological pilot study to analyze wheelchair propulsion upper limb kinematics in standard competitive play considering the functional classification of each athlete. Ten basketball players with a functional classification ranging from 1 to 4 were included in the study. Four camcorders (Kinescan-IBV) and a treadmill for wheelchairs were used. Temporal parameters were analyzed and the upper limb kinematics was obtained using ISB recommendations. The value of the temporal parameters such as push phase duration, the ratio of push phase/recovery phase, contact, and propulsion angle seems to reduce as the functional classification increases. A methodological protocol has been developed that allows the analysis of kinematic characteristics of wheelchair propulsion in basketball players taking into account their functional classification.

  17. Comparing handrim biomechanics for treadmill and overground wheelchair propulsion

    Science.gov (United States)

    Kwarciak, Andrew M.; Turner, Jeffrey T.; Guo, Liyun; Richter, W. Mark

    2010-01-01

    Study design Cross-sectional study. Objectives To compare handrim biomechanics recorded during overground propulsion to those recorded during propulsion on a motor-driven treadmill. Setting Biomechanics laboratory. Methods Twenty-eight manual wheelchair users propelled their own wheelchairs, at a self-selected speed, on a low-pile carpet and on a wheelchair accessible treadmill. Handrim biomechanics were recorded with an OptiPush instrumented wheelchair wheel. Results Across the two conditions, all handrim biomechanics were found to be similar and highly correlated (r > 0.85). Contact angle, peak force, average force, and peak axle moment differed by 1.6% or less across the two conditions. While not significant, power output and cadence tended to be slightly higher for the treadmill condition (3.5% and 3.6%, respectively), due to limitations in adjusting the treadmill grade. Conclusion Based on the results of this study, a motor-driven treadmill can serve as a valid surrogate for overground studies of wheelchair propulsion. PMID:21042332

  18. Wheelchair propulsion biomechanics and wheelers' quality of life: an exploratory review.

    Science.gov (United States)

    Chow, John W; Levy, Charles E

    2011-01-01

    PURPOSE. To provide an overview of associations between wheelchair propulsion biomechanics for both everyday and racing wheelchairs, wheeling-related upper limb injuries, and quality of life of manual wheelchair users through a synthesis of the available information. METHODS. A search of publications was carried out in PubMed and SportsDiscus databases. Studies on wheelchair propulsion biomechanics, upper limb injuries associated with wheelchair propulsion and quality of life of wheelchair users were identified. Relevant articles cited in identified articles but not cited in PubMed or SportsDiscus were also included. RESULTS. Wheelchair sports participation has positive impact on quality of life and research in racing wheelchair biomechanics can indirectly promote the visibility of wheelchair sports. The impact of pushrim-activated power-assisted wheelchairs (a hybrid between manual and battery-powered wheelchairs) and geared manual wheels on wheelers' everyday life were discussed. CONCLUSIONS. The study of wheelchair propulsion biomechanics focuses on how a wheelchair user imparts power to the wheels to achieve mobility and the accumulated knowledge can help to improve wheelchair users' mobility, reduce physical stress associated with wheelchair propulsion, and as a result, enhance quality of life.

  19. Manual wheelchair stroke characteristics during an extended period of propulsion.

    Science.gov (United States)

    Rice, I; Impink, B; Niyonkuru, C; Boninger, M

    2009-05-01

    Cross-sectional study. The purpose of this study was to examine stroke characteristics of long-term manual wheelchair users during an extended manual wheelchair propulsion trial and the extent to which changes in propulsion biomechanics occurred. Human Engineering Research Laboratories, VA Rehabilitation Research and Development Center, VA Pittsburgh Healthcare Systems, Pittsburgh, PA, USA. Kinetic data were recorded from 21 subjects with paraplegia at four time points over the course of a 10-min propulsion trial at a steady state speed of 1.4 m s(-1). Upper extremity kinetic parameters were recorded using Smartwheels, force and torque sensing pushrims. Subjects for propulsion biomechanics changed from early to late during the 10-min trial. Individuals displayed decreased maximum rate of rise of resultant force (P=0.0045) with a simultaneous increase in push time (P=0.043) and stroke time (P=0.023), whereas stroke frequency remained static. In addition, there was a decrease in out of plane moment application (P=0.032). Individuals seemed to naturally accommodate their propulsive stroke, using less injurious propulsion biomechanics over the course of a 10-minute trial on a dynamometer. The findings may have occurred as a result of both biomechanical compensations to a challenging propulsion trial and accommodation to propelling on a dynamometer. These results suggest that subjects may be capable of independently incorporating favorable biomechanical strategies to meet the demands of a challenging propulsion scenario.

  20. Shoulder joint kinetics during the push phase of wheelchair propulsion.

    Science.gov (United States)

    Kulig, K; Rao, S S; Mulroy, S J; Newsam, C J; Gronley, J K; Bontrager, E L; Perry, J

    1998-09-01

    The purpose of this investigation was to quantify the forces and moments at the shoulder joint during free, level wheelchair propulsion and to document changes imposed by increased speed, inclined terrain, and 15 minutes of continuous propulsion. Data were collected using a six-camera VICON motion analysis system, a strain gauge instrumented wheel, and a wheelchair ergometer. Seventeen men with low level paraplegia participated in this study. Shoulder joint forces and moments were calculated using a three-dimensional model applying the inverse dynamics approach. During free propulsion, peak shoulder joint forces were in the posterior (46 N) and superior directions (14 N), producing a peak resultant force of 51 N at an angle of 185 degrees (180 degrees = posterior). Peak shoulder joint moments were greatest in extension (14 Newton-meters [Nm]), followed by abduction (10 Nm), and internal rotation (6 Nm). With fast and inclined propulsion, peak vertical force increased by greater than 360%, and the increase in posterior force and shoulder moments ranged from 107% to 167%. At the end of 15 minutes of continuous free propulsion, there were no significant changes compared with short duration free propulsion. The increased joint loads documented during fast and inclined propulsion could lead to compression of subacromial structures against the overlying acromion.

  1. Biomechanic evaluation of upper-extremity symmetry during manual wheelchair propulsion over varied terrain.

    Science.gov (United States)

    Hurd, Wendy J; Morrow, Melissa M; Kaufman, Kenton R; An, Kai-Nan

    2008-10-01

    To evaluate upper-extremity symmetry during wheelchair propulsion across multiple terrain surfaces. Case series. A biomechanics laboratory and the general community. Manual wheelchair users (N=12). Not applicable. Symmetry indexes for the propulsion moment, total force, tangential force, fractional effective force, time-to-peak propulsion moment, work, length of push cycle, and power during wheelchair propulsion over outdoor and indoor community conditions, and in laboratory conditions. Upper-extremity asymmetry was present within each condition. There were no differences in the magnitude of asymmetry when comparing laboratory with indoor community conditions. Outdoor community wheelchair propulsion asymmetry was significantly greater than asymmetry measured during laboratory conditions. Investigators should be aware that manual wheelchair propulsion is an asymmetrical act, which may influence interpretation when data is collected from a single limb or averaged for both limbs. The greater asymmetry identified during outdoor versus laboratory conditions emphasizes the need to evaluate wheelchair biomechanics in the user's natural environment.

  2. Temporal Parameters Estimation for Wheelchair Propulsion Using Wearable Sensors

    Directory of Open Access Journals (Sweden)

    Manoela Ojeda

    2014-01-01

    Full Text Available Due to lower limb paralysis, individuals with spinal cord injury (SCI rely on their upper limbs for mobility. The prevalence of upper extremity pain and injury is high among this population. We evaluated the performance of three triaxis accelerometers placed on the upper arm, wrist, and under the wheelchair, to estimate temporal parameters of wheelchair propulsion. Twenty-six participants with SCI were asked to push their wheelchair equipped with a SMARTWheel. The estimated stroke number was compared with the criterion from video observations and the estimated push frequency was compared with the criterion from the SMARTWheel. Mean absolute errors (MAE and mean absolute percentage of error (MAPE were calculated. Intraclass correlation coefficients and Bland-Altman plots were used to assess the agreement. Results showed reasonable accuracies especially using the accelerometer placed on the upper arm where the MAPE was 8.0% for stroke number and 12.9% for push frequency. The ICC was 0.994 for stroke number and 0.916 for push frequency. The wrist and seat accelerometer showed lower accuracy with a MAPE for the stroke number of 10.8% and 13.4% and ICC of 0.990 and 0.984, respectively. Results suggested that accelerometers could be an option for monitoring temporal parameters of wheelchair propulsion.

  3. Effect of holding a racket on propulsion technique of wheelchair tennis players

    NARCIS (Netherlands)

    de Groot, S.; Bos, F.; Koopman, J.; Hoekstra, A. E.; Vegter, R. J. K.

    The purpose of this study was to determine possible differences in propulsion technique between propelling the wheelchair with and without a racket in the hand. Eight experienced wheelchair tennis players performed three submaximal exercise tests and six sprint tests on a wheelchair ergometer.

  4. Quasi-static analysis of muscle forces in the shoulder mechanism during wheelchair propulsion

    NARCIS (Netherlands)

    van der Helm, Frans C T; Veeger, H. E J

    During wheelchair propulsion the largest net joint moments and net joint powers are generated around the shoulder. The analysis of the contribution of arm- and shoulder muscles to the joint moments could explain the low efficiency of wheelchair propulsion. Basically, it is assumed that a large

  5. Effect Of Variable Practice On The Motor Learning Process In Manual Wheelchair Propulsion

    NARCIS (Netherlands)

    Leving, Marika T; Vegter, Riemer J K; de Groot, Sonja; van der Woude, Lucas H V

    Handrim wheelchair propulsion is a cyclic skill that needs to be learned during rehabilitation. It has been suggested that a higher intra-individual variability benefits the motor learning process of wheelchair propulsion. PURPOSE: The goal of the current study was to determine the effect of

  6. A wheelchair with lever propulsion control for climbing up and down stairs.

    Science.gov (United States)

    Sasaki, Kai; Eguchi, Yosuke; Suzuki, Kenji

    2016-08-01

    This study proposes a novel stair-climbing wheelchair based on lever propulsion control using the human upper body. Wheelchairs are widely used as supporting locomotion devices for people with acquired lower limb disabilities. However, steps and stairs are critical obstacles to locomotion, which restrict their activities when using wheelchairs. Previous research focused on power-assisted, stair-climbing wheelchairs, which were large and heavy due to its large actuators and mechanisms. In the previous research, we proposed a wheelchair with lever propulsion mechanism and presented its feasibility of climbing up the stairs. The developed stair-climbing wheelchair consists of manual wheels with casters for planar locomotion and a rotary-leg mechanism based on lever propulsion that is capable of climbing up stairs. The wheelchair also has a passive mechanism powered by gas springs for posture transition to shift the user's center of gravity between the desired positions for planar locomotion and stair-climbing. In this paper, we present an advanced study on both climbing up and going down using lever propulsion control by the user's upper body motion. For climbing down the stairs, we reassembled one-way clutches used for the rotary-leg mechanism to help a user climb down the stairs through lever operation. We also equipped the wheelchair with sufficient torque dampers. The frontal wheels were fixed while climbing down the stairs to ensure safety. Relevant experiments were then performed to investigate its performance and verify that the wheelchair users can operate the proposed lever propulsion mechanism.

  7. Effects of wheel and hand-rim size on submaximal propulsion in wheelchair athletes.

    Science.gov (United States)

    Mason, Barry S; Van Der Woude, Lucas H V; Tolfrey, Keith; Lenton, John P; Goosey-Tolfrey, Victoria L

    2012-01-01

    This study aimed to investigate the effects of fixed gear ratio wheel sizes on the physiological and biomechanical responses to submaximal wheelchair propulsion. Highly trained wheelchair basketball players (N = 13) propelled an adjustable sports wheelchair in three different wheel sizes (24, 25, and 26 inches) on a motor-driven treadmill. Each wheel was equipped with force-sensing hand-rims (SMARTWheel), which collected kinetic and temporal data. Oxygen uptake (V˙O2) and HR responses were measured with high-speed video footage collected to determine three-dimensional upper body joint kinematics. Mean power output and work per cycle decreased progressively with increasing wheel size (P wheelchair propulsion.

  8. Wheelchair Propulsion Biomechanics in Junior Basketball Players: A Method for the Evaluation of the Efficacy of a Specific Training Program

    National Research Council Canada - National Science Library

    Bergamini, Elena; Morelli, Francesca; Marchetti, Flavia; Vannozzi, Giuseppe; Polidori, Lorenzo; Paradisi, Francesco; Traballesi, Marco; Cappozzo, Aurelio; Delussu, Anna Sofia

    2015-01-01

    .... The present study focuses on junior wheelchair basketball and aims at (i) proposing a method to identify biomechanical performance indicators of wheelchair propulsion using an instrumented in-field test and (ii...

  9. Variability of peak shoulder force during wheelchair propulsion in manual wheelchair users with and without shoulder pain.

    Science.gov (United States)

    Moon, Y; Jayaraman, C; Hsu, I M K; Rice, I M; Hsiao-Wecksler, E T; Sosnoff, J J

    2013-01-01

    Manual wheelchair users report a high prevalence of shoulder pain. Growing evidence shows that variability in forces applied to biological tissue is related to musculoskeletal pain. The purpose of this study was to examine the variability of forces acting on the shoulder during wheelchair propulsion as a function of shoulder pain. Twenty-four manual wheelchair users (13 with pain, 11 without pain) participated in the investigation. Kinetic and kinematic data of wheelchair propulsion were recorded for 3 min maintaining a constant speed at three distinct propulsion speeds (fast speed of 1.1 m/s, a self-selected speed, and a slow speed of 0.7 m/s). Peak resultant shoulder forces in the push phase were calculated using inverse dynamics. Within individual variability was quantified as the coefficient of variation of cycle to cycle peak resultant forces. There was no difference in mean peak shoulder resultant force between groups. The pain group had significantly smaller variability of peak resultant force than the no pain group (Ppain in manual wheelchair users. © 2013.

  10. Biomechanic Evaluation of Upper-Extremity Symmetry Manual Wheelchair Propulsion Over Varied Terrain

    Science.gov (United States)

    Hurd, Wendy J.; Morrow, Melissa M.; Kaufman, Kenton R.; An, Kai-Nan

    2014-01-01

    Objective To evaluate upper-extremity symmetry during wheelchair propulsion across multiple terrain surfaces. Design Case series. Setting A biomechanics laboratory and the community. Participants Manual wheelchair users (N=12). Interventions Not applicable. Main Outcome Measures Symmetry indexes for the propulsion moment, total force, tangential force, fractional effective force, time-to-peak propulsion moment, work, length of push cycle, and power during wheelchair propulsion over outdoor and indoor community conditions, and in conditions. Results Upper-extremity asymmetry was present within each condition. There were no differences in the magnitude of asymmetry when comparing laboratory with indoor community conditions. Outdoor community wheelchair propulsion asymmetry was significantly greater than asymmetry measured during laboratory conditions. Conclusions Investigators should be aware that manual wheelchair propulsion is an asymmetrical act, which may influence interpretation when data is collected from a single limb or averaged for both limbs. The greater asymmetry identified during outdoor versus laboratory conditions the emphasizes need to evaluate wheelchair biomechanics in the user’s natural environment. PMID:18929029

  11. Validation of a Biofeedback System for Wheelchair Propulsion Training

    Directory of Open Access Journals (Sweden)

    Liyun Guo

    2011-01-01

    Full Text Available This paper describes the design and validation of the OptiPush Biofeedback System, a commercially available, instrumented wheel system that records handrim biomechanics and provides stroke-by-stroke biofeedback and targeting for 11 propulsion variables. Testing of the system revealed accurate measurement of wheel angle (0.02% error, wheel speed (0.06% error, and handrim loads. The maximum errors in static force and torque measurements were 3.80% and 2.05%, respectively. Measured forces were also found to be highly linear (0.985 .998. Dynamic measurements of planar forces ( and and axle torque also had low error (−0.96 N to 0.83 N for force and 0.10 Nm to 0.14 Nm for torque and were highly correlated (r > .986 with expected force and torque values. Overall, the OptiPush Biofeedback System provides accurate measurement of wheel dynamics and handrim biomechanics and may be a useful tool for improving manual wheelchair propulsion.

  12. Hand-rim Forces and Gross Mechanical Efficiency at Various Frequencies of Wheelchair Propulsion

    NARCIS (Netherlands)

    Lenton, J. P.; van der Woude, L. H. V.; Fowler, N. E.; Nicholson, G.; Tolfrey, K.; Goosey-Tolfrey, V. L.

    To determine the effects of push frequency changes on force application, fraction of effective force (FEF) and gross efficiency (GE) during hand-rim propulsion. 8 male able-bodied participants performed five 4-min sub-maximal exercise bouts at 1.8 m.s(-1); the freely chosen frequency (FCF), followed

  13. Effects of synchronous versus asynchronous mode of propulsion on wheelchair basketball sprinting.

    Science.gov (United States)

    Faupin, Arnaud; Borel, Benoit; Meyer, Christophe; Gorce, Philippe; Watelain, Eric

    2013-11-01

    This study aimed to first investigate synchronous (SYN) versus asynchronous (ASY) mode of propulsion and, second, investigate the wheel camber effects on sprinting performance as well as temporal parameters. Seven wheelchair basketball players performed four maximal eight-second sprints on a wheelchair ergometer. They repeated the test according to two modes of propulsion (SYN and ASY) and two wheel cambers (9° and 15°). The mean maximal velocity and push power output was greater in the synchronous mode compared to the asynchronous mode for both camber angles. However, the fluctuation in the velocity profile is inferior for ASY versus SYN mode for both camber angles. Greater push time/cycle time (Pt/Ct) and arm frequency (AF) for synchronous mode versus asynchronous mode and inversely, lesser Ct and rest time (Rt) values for the synchronous mode, for which greater velocity were observed. SYN mode leads to better performance than ASY mode in terms of maximal propulsion velocity. However, ASY propulsion allows greater continuity of the hand-rim force application, reducing fluctuations in the velocity profile. The camber angle had no effect on ASY and SYN mean maximal velocity and push power output. The study of wheelchair propulsion strategies is important for better understanding physiological and biomechanical impacts of wheelchair propulsion for individuals with disabilities. From a kinematical point of view, this study highlights synchronous mode of propulsion to be more efficient, with regards to mean maximal velocity reaching during maximal sprinting exercises. Even if this study focuses on well-trained wheelchair athletes, results from this study could complement the knowledge on the physiological and biomechanical adaptations to wheelchair propulsion and therefore, might be interesting for wheelchair modifications for purposes of rehabilitation.

  14. Shoulder pain and jerk during recovery phase of manual wheelchair propulsion.

    Science.gov (United States)

    Jayaraman, Chandrasekaran; Beck, Carolyn L; Sosnoff, Jacob J

    2015-11-05

    Repetitive loading of the upper limb due to wheelchair propulsion plays a leading role in the development of shoulder pain in manual wheelchair users (mWCUs). There has been minimal inquiry on understanding wheelchair propulsion kinematics from a human movement ergonomics perspective. This investigation employs an ergonomic metric, jerk, to characterize the recovery phase kinematics of two recommended manual wheelchair propulsion patterns: semi-circular and the double loop. Further it examines if jerk is related to shoulder pain in mWCUs. Data from 22 experienced adult mWCUs was analyzed for this study (semi-circular: n=12 (pain/without-pain:6/6); double-loop: n=10 (pain/without-pain:4/6)). Participants propelled their own wheelchair fitted with SMARTWheels on a roller dynamometer at 1.1 m/s for 3 min. Kinematic and kinetic data of the upper limbs were recorded. Three dimensional absolute jerk experienced at the shoulder, elbow and wrist joint during the recovery phase of wheelchair propulsion were computed. Two-way ANOVAs were conducted with the recovery pattern type and shoulder pain as between group factors. (1) Individuals using a semi-circular pattern experienced lower jerk at their arm joints than those using a double loop pattern (Pwrist;(P=0.05, η(2)=0.19)elbow;(Pwrist;(P≤0.05, η(2)=0.30)elbow;(P≤0.05, η(2)=0.31)shoulder. Jerk during wheelchair propulsion was able to distinguish between pattern types (semi-circular and double loop) and the presence of shoulder pain. Jerk provides novel insights into wheelchair propulsion kinematics and in the future it may be beneficial to incorporate jerk based metric into rehabilitation practice. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Effect of power-assisted hand-rim wheelchair propulsion on shoulder load in experienced wheelchair users : A pilot study with an instrumented wheelchair

    NARCIS (Netherlands)

    Kloosterman, Marieke G. M.; Buurke, Jaap H.; de Vries, Wiebe; Van der Woude, Lucas H. V.; Rietman, Johan S.

    2015-01-01

    This study aims to compare hand-rim and power-assisted hand-rim propulsion on potential risk factors for shoulder overuse injuries: intensity and repetition of shoulder loading and force generation in the extremes of shoulder motion. Eleven experienced hand-rim wheelchair users propelled an

  16. Effect of power-assisted hand-rim wheelchair propulsion on shoulder load in experienced wheelchair users: A pilot study with an instrumented wheelchair

    NARCIS (Netherlands)

    Kloosterman, Marieke; Buurke, Jaap; de Vries, W.; de Vries, W.; van der Woude, L.H.V.; Rietman, Johan Swanik

    2015-01-01

    This study aims to compare hand-rim and power-assisted hand-rim propulsion on potential risk factors for shoulder overuse injuries: intensity and repetition of shoulder loading and force generation in the extremes of shoulder motion. Eleven experienced hand-rim wheelchair users propelled an

  17. Effects of variable practice on the motor learning outcomes in manual wheelchair propulsion.

    Science.gov (United States)

    Leving, Marika T; Vegter, Riemer J K; de Groot, Sonja; van der Woude, Lucas H V

    2016-11-23

    Handrim wheelchair propulsion is a cyclic skill that needs to be learned during rehabilitation. It has been suggested that more variability in propulsion technique benefits the motor learning process of wheelchair propulsion. The purpose of this study was to determine the influence of variable practice on the motor learning outcomes of wheelchair propulsion in able-bodied participants. Variable practice was introduced in the form of wheelchair basketball practice and wheelchair-skill practice. Motor learning was operationalized as improvements in mechanical efficiency and propulsion technique. Eleven Participants in the variable practice group and 12 participants in the control group performed an identical pre-test and a post-test. Pre- and post-test were performed in a wheelchair on a motor-driven treadmill (1.11 m/s) at a relative power output of 0.23 W/kg. Energy consumption and the propulsion technique variables with their respective coefficient of variation were calculated. Between the pre- and the post-test the variable practice group received 7 practice sessions. During the practice sessions participants performed one-hour of variable practice, consisting of five wheelchair-skill tasks and a 30 min wheelchair basketball game. The control group did not receive any practice between the pre- and the post-test. Comparison of the pre- and the post-test showed that the variable practice group significantly improved the mechanical efficiency (4.5 ± 0.6% → 5.7 ± 0.7%) in contrast to the control group (4.5 ± 0.6% → 4.4 ± 0.5%) (group x time interaction effect p < 0.001).With regard to propulsion technique, both groups significantly reduced the push frequency and increased the contact angle of the hand with the handrim (within group, time effect). No significant group × time interaction effects were found for propulsion technique. With regard to propulsion variability, the variable practice group increased variability when

  18. Do Performance-Based Wheelchair Propulsion Tests Detect Changes Among Manual Wheelchair Users With Spinal Cord Injury During Inpatient Rehabilitation in Quebec?

    Science.gov (United States)

    Gagnon, Dany H; Roy, Audrey; Verrier, Molly C; Duclos, Cyril; Craven, B Cathy; Nadeau, Sylvie

    2016-07-01

    To quantify and compare the responsiveness and concurrent validity of 3 performance-based manual wheelchair propulsion tests among manual wheelchair users with subacute spinal cord injury (SCI) undergoing inpatient rehabilitation. Quasi-experimental repeated-measures design. Publicly funded comprehensive inpatient SCI rehabilitation program. Consenting adult manual wheelchair users with a subacute SCI admitted and discharged from inpatient rehabilitation (N=14). Participants performed 20-m propulsion at both self-selected natural and maximal speeds, the slalom, and the 6-minute propulsion tests at rehabilitation admission and discharge. Time required to complete the performance-based wheelchair propulsion tests. Standardized response means (SRMs) were computed for each performance test and Pearson correlation coefficients (r) were calculated to explore the associations between performance tests. The slalom (SRM=1.24), 20-m propulsion at maximum speed (SRM=.99), and 6-minute propulsion tests (SRM=.84) were the most responsive. The slalom and 20-m propulsion at maximum speed were strongly correlated at both admission (r=.93) and discharge (r=.92). The slalom and 6-minute propulsion tests best document wheelchair propulsion performance change over the course of inpatient rehabilitation. Adding the 20-m propulsion test performed at maximal speed provides a complementary description of performance change. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  19. Alternative modes of manual wheelchair propulsion: an overview

    NARCIS (Netherlands)

    van der Woude, L.H.V.; Veeger, H.E.J.; Dallmeijer, A.J.; Janssen, T.W.J.

    2001-01-01

    An estimated 90% of all wheelchairs are hand-rim propelled, a physically straining form of ambulation that can lead to repetitive strain injuries in the arms and, eventually, to secondary impairments and disability. Further disability in wheelchair-dependent individuals can lead to a sedentary

  20. Upper limb joint motion of two different user groups during manual wheelchair propulsion

    Science.gov (United States)

    Hwang, Seonhong; Kim, Seunghyeon; Son, Jongsang; Lee, Jinbok; Kim, Youngho

    2013-02-01

    Manual wheelchair users have a high risk of injury to the upper extremities. Recent studies have focused on kinematic and kinetic analyses of manual wheelchair propulsion in order to understand the physical demands on wheelchair users. The purpose of this study was to investigate upper limb joint motion by using a motion capture system and a dynamometer with two different groups of wheelchair users propelling their wheelchairs at different speeds under different load conditions. The variations in the contact time, release time, and linear velocity of the experienced group were all larger than they were in the novice group. The propulsion angles of the experienced users were larger than those of the novices under all conditions. The variances in the propulsion force (both radial and tangential) of the experienced users were larger than those of the novices. The shoulder joint moment had the largest variance with the conditions, followed by the wrist joint moment and the elbow joint moment. The variance of the maximum shoulder joint moment was over four times the variance of the maximum wrist joint moment and eight times the maximum elbow joint moment. The maximum joint moments increased significantly as the speed and load increased in both groups. Quick and significant manipulation ability based on environmental changes is considered an important factor in efficient propulsion. This efficiency was confirmed from the propulsion power results. Sophisticated strategies for efficient manual wheelchair propulsion could be understood by observation of the physical responses of each upper limb joint to changes in load and speed. We expect that the findings of this study will be utilized for designing a rehabilitation program to reduce injuries.

  1. A Modeling Framework to Investigate the Radial Component of the Pushrim Force in Manual Wheelchair Propulsion

    Directory of Open Access Journals (Sweden)

    Ackermann Marko

    2015-01-01

    Full Text Available The ratio of tangential to total pushrim force, the so-called Fraction Effective Force (FEF, has been used to evaluate wheelchair propulsion efficiency based on the fact that only the tangential component of the force on the pushrim contributes to actual wheelchair propulsion. Experimental studies, however, consistently show low FEF values and recent experimental as well as modelling investigations have conclusively shown that a more tangential pushrim force direction can lead to a decrease and not increase in propulsion efficiency. This study aims at quantifying the contributions of active, inertial and gravitational forces to the normal pushrim component. In order to achieve this goal, an inverse dynamics-based framework is proposed to estimate individual contributions to the pushrim forces using a model of the wheelchair-user system. The results show that the radial pushrim force component arise to a great extent due to purely mechanical effects, including inertial and gravitational forces. These results corroborate previous findings according to which radial pushrim force components are not necessarily a result of inefficient propulsion strategies or hand-rim friction requirements. This study proposes a novel framework to quantify the individual contributions of active, inertial and gravitational forces to pushrim forces during wheelchair propulsion.

  2. Wrist biomechanics during two speeds of wheelchair propulsion: an analysis using a local coordinate system.

    Science.gov (United States)

    Boninger, M L; Cooper, R A; Robertson, R N; Rudy, T E

    1997-04-01

    To describe motion, forces, and moments occurring at the wrist in anatomic terms during wheelchair propulsion; to obtain variables that characterize wrist function during propulsion and are statistically stable; and to determine how these variables change with speed. Case series. Biomechanics laboratory. Convenience sample of Paralympic athletes (n = 6) who use manual wheelchairs for mobility and have unimpaired arm function. Subjects propelled a standard wheelchair on a dynamometer at 1.3m/sec and 2.2m/sec. Biomechanical data were obtained using a force and moment sensing pushrim and a motion analysis system. Maximum angles, forces, and moments in a local, wrist coordinate system. Each variable was evaluated for stability using Cronbach's alpha. Measures found to be stable (infinity > .8) at each speed were then compared to look for differences associated with speed. The following measures were stable at both speeds: maximum wrist flexion, ulnar deviation, and radial deviation angles, peak moments acting to cause wrist flexion, extension, and ulnar deviation, peak shear forces acting between the radial and ulnar styloids, and peak axial force acting at the wrist. Of these measures, the following measures differed (p wrist biomechanics during wheelchair propulsion and varied with speed. Ultimately these parameters may provide insight into the cause and prevention of wrist injuries in manual wheelchair users.

  3. SMARTWheels: development and testing of a system for measuring manual wheelchair propulsion dynamics.

    Science.gov (United States)

    Asato, K T; Cooper, R A; Robertson, R N; Ster, J F

    1993-12-01

    The purpose of this project was to develop a system for dynamically sensing pushrim propulsion forces and torques and to collect kinetic data with the device. A system was developed to detect the forces and torques applied to the wheelchair pushrim, record, store, and process the measured data, and display the kinetic information for analysis. Ten adults, including four male wheelchair users, three ambulatory men, and three ambulatory women, pushed a wheelchair with the SMARTWheel on a dynamometer while their kinematics were videotaped. The kinetic data collected with our wheel were correlated with stick figure representations of digitized kinematic data obtained through video analysis. The close agreement between the kinetic results and the Kinematic results provided a temporal validation of the ability of the wheel to detect forces and torques applied to the wheelchair pushrim. The recorded forces and torques were in agreement with previously reported magnitudes.

  4. Effectiveness of force application in manual wheelchair propulsion in persons with spinal cord injuries

    NARCIS (Netherlands)

    Dallmeijer, A.J.; van der Woude, L.H.V.; Veeger, H.E.J.; Hollander, A.P.

    1998-01-01

    The objective of this study was to investigate effectiveness of force application, the ratio power output/energy expenditure, and timing parameters of wheelchair propulsion in persons with tetraplegia (TP, n = 17) and paraplegia (PP, n = 12), at two different intensity conditions. All subjects

  5. Range of motion and stroke frequency differences between manual wheelchair propulsion and pushrim-activated power-assisted wheelchair propulsion.

    Science.gov (United States)

    Corfman, Thomas A; Cooper, Rory A; Boninger, Michael L; Koontz, Alicia M; Fitzgerald, Shirley G

    2003-01-01

    The objective of this study was to examine the use and efficacy of a pushrim-activated power-assist wheelchair (PAPAW) in the reduction of upper extremity range of motion (ROM) and stroke frequency in manual wheelchair users. Ten manual wheelchair users were evaluated using a repeated-measures design with and without the use of a PAPAW for maximum ROM of shoulder flexion/extension, abduction/adduction, internal/external rotation, and horizontal flexion/extension; elbow flexion/extension; wrist flexion/extension, supination/pronation, and ulnar/radial deviation; and stroke frequency. Participants propelled a Quickie 2 manual wheelchair configured as a PAPAW and their own wheelchair on a computer-controlled dynamometer at 3 different resistance levels and 2 different speeds. The use of the PAPAW significantly (P wrist flexion/extension and ulnar/radial deviation for many speed and resistance combinations. Univariate analysis revealed that stroke frequency was unaltered in all cases. These findings provide the foundation for studying the utility of the PAPAW in reducing the risk of upper limb injury and neuropathy in the manual wheelchair user population.

  6. Trunk and neck kinematics during overground manual wheelchair propulsion in persons with tetraplegia.

    Science.gov (United States)

    Julien, Marie C; Morgan, Kerri; Stephens, Christina L; Standeven, John; Engsberg, Jack

    2014-05-01

    To test the hypothesis that movement of the head and trunk increases as a consequence of speed during manual wheelchair propulsion over the ground in individuals with tetraplegia. Seven adult participants with tetraplegia who used manual wheelchairs (5 men and 2 women, aged 33.0 ± 10.2) were selected for the study. Participants propelled over the ground at three different speeds while video motion capture methods collected kinematic data. Variables investigated were forward flexion, lateral flexion and axial rotation for both the head and trunk. Repeated measures ANOVA were used to determine effects of speed on head and trunk movements. Both neck and trunk forward flexion significantly increased as a result of speed (p = 0.034, p = 0.031), with a large effect size (r = 0.6, r = 0.6) between slow and fast speeds. Lateral flexion and axial rotation were minimal for the neck and trunk and did not significantly increase with speed. Results suggest that manual wheelchair users with tetraplegia compensate for trunk muscle weakness by flexing the upper trunk and neck forward during manual wheelchair propulsion and that these movements increase with speed. Further studies should examine if these movements relate to overuse injuries and interventions that focus on improving manual wheelchair biomechanics of individuals with tetraplegia. Individuals who use manual wheelchairs utilize their upper extremities almost exclusively for both everyday mobility and participation in daily life activities which can often lead to overuse injuries and pain. Despite having a lack of trunk muscle innervation, manual wheelchair users with tetraplegia are able to compensate for this weakness by using the upper trunk and neck. The way in which force is translated from the trunk through the upper extremities to the pushrim may impact propulsion biomechanics, and ultimately the extent in which upper extremity pain and injury develops. A better understanding of how

  7. Effect of handrim velocity on mechanical efficiency in wheelchair propulsion

    NARCIS (Netherlands)

    Veeger, DirkJan (H. E. J.); van der Woude, L H; Rozendal, R H

    To study the effect of tangential speed of the handrims independent of external power output on gross mechanical efficiency (ME), nine able-bodied subjects performed wheelchair exercise tests on a stationary ergometer. The ergometer allowed for measurement of torque and three-dimensional forces on

  8. A kinetic analysis of manual wheelchair propulsion during start-up on select indoor and outdoor surfaces

    NARCIS (Netherlands)

    Koontz, AM; Cooper, RA; Boninger, ML; Yang, YS; Impink, BG; van der Woude, LHV

    2005-01-01

    The objective of this study was to conduct a kinetic analysis of manual wheelchair propulsion during start-LIP on select indoor and Outdoor surfaces. Eleven manual wheelchairs were fitted with a SMART(Wheel) and their users were asked to Push on a Course consisting of high- and low-pile carpet,

  9. Hand rim wheelchair propulsion training using biomechanical real-time visual feedback based on motor learning theory principles.

    Science.gov (United States)

    Rice, Ian; Gagnon, Dany; Gallagher, Jere; Boninger, Michael

    2010-01-01

    As considerable progress has been made in laboratory-based assessment of manual wheelchair propulsion biomechanics, the necessity to translate this knowledge into new clinical tools and treatment programs becomes imperative. The objective of this study was to describe the development of a manual wheelchair propulsion training program aimed to promote the development of an efficient propulsion technique among long-term manual wheelchair users. Motor learning theory principles were applied to the design of biomechanical feedback-based learning software, which allows for random discontinuous real-time visual presentation of key spatiotemporal and kinetic parameters. This software was used to train a long-term wheelchair user on a dynamometer during 3 low-intensity wheelchair propulsion training sessions over a 3-week period. Biomechanical measures were recorded with a SmartWheel during over ground propulsion on a 50-m level tile surface at baseline and 3 months after baseline. Training software was refined and administered to a participant who was able to improve his propulsion technique by increasing contact angle while simultaneously reducing stroke cadence, mean resultant force, peak and mean moment out of plane, and peak rate of rise of force applied to the pushrim after training. The proposed propulsion training protocol may lead to favorable changes in manual wheelchair propulsion technique. These changes could limit or prevent upper limb injuries among manual wheelchair users. In addition, many of the motor learning theory-based techniques examined in this study could be applied to training individuals in various stages of rehabilitation to optimize propulsion early on.

  10. Changes in oxygen uptake, shoulder muscles activity, and propulsion cycle timing during strenuous wheelchair exercise.

    Science.gov (United States)

    Bernasconi, S M; Tordi, N; Ruiz, J; Parratte, B

    2007-07-01

    Cross-over study. To determine the effect of strenuous wheelchair exercise on oxygen uptake (VO2 ), muscle activity and propulsion cycle timing (including the push time and recovery time during one full arm cycle). Laboratory of Sport Sciences at the University of France-Comte in France. Two exercise bouts of 6-min duration were performed at a constant workload: (1) non-fatigable exercise (moderate workload) and (2) fatigable exercise (heavy workload). Measurement of VO2, surface electromyographic activity (EMG) from shoulder muscles, and temporal parameters of wheelchair ergometer propulsion were collected from eight able-bodied men (26+/-4 years). A progressive increase in VO2 associated with EMG alterations (Pmuscle activation time (Pfatigue and inefficient muscle coordination, which may contribute to deleterious stress distributions at the shoulder joint, increasing susceptibility to injury.

  11. Effects of visual feedback-induced variability on motor learning of handrim wheelchair propulsion.

    Science.gov (United States)

    Leving, Marika T; Vegter, Riemer J K; Hartog, Johanneke; Lamoth, Claudine J C; de Groot, Sonja; van der Woude, Lucas H V

    2015-01-01

    It has been suggested that a higher intra-individual variability benefits the motor learning of wheelchair propulsion. The present study evaluated whether feedback-induced variability on wheelchair propulsion technique variables would also enhance the motor learning process. Learning was operationalized as an improvement in mechanical efficiency and propulsion technique, which are thought to be closely related during the learning process. 17 Participants received visual feedback-based practice (feedback group) and 15 participants received regular practice (natural learning group). Both groups received equal practice dose of 80 min, over 3 weeks, at 0.24 W/kg at a treadmill speed of 1.11 m/s. To compare both groups the pre- and post-test were performed without feedback. The feedback group received real-time visual feedback on seven propulsion variables with instruction to manipulate the presented variable to achieve the highest possible variability (1st 4-min block) and optimize it in the prescribed direction (2nd 4-min block). To increase motor exploration the participants were unaware of the exact variable they received feedback on. Energy consumption and the propulsion technique variables with their respective coefficient of variation were calculated to evaluate the amount of intra-individual variability. The feedback group, which practiced with higher intra-individual variability, improved the propulsion technique between pre- and post-test to the same extent as the natural learning group. Mechanical efficiency improved between pre- and post-test in the natural learning group but remained unchanged in the feedback group. These results suggest that feedback-induced variability inhibited the improvement in mechanical efficiency. Moreover, since both groups improved propulsion technique but only the natural learning group improved mechanical efficiency, it can be concluded that the improvement in mechanical efficiency and propulsion technique do not always appear

  12. Effects of Wheelchair Seat-height Settings on Alternating Lower Limb Propulsion With Both Legs.

    Science.gov (United States)

    Murata, Tomoyuki; Asami, Toyoko; Matsuo, Kiyomi; Kubo, Atsuko; Okigawa, Etsumi

    2014-01-01

    This study investigated the effects of seat-height settings of wheelchairs with alternating propulsion with both legs. Seven healthy individuals with no orthopedic disease participated. Flexion angles at initial contact (FA-IC) of each joint, range of motion during propulsion period (ROM-PP), and ground reaction force (GRF) were measured using a three dimensional motion capture system and force plates, and compared with different seat-height settings. Statistically significant relationships were found between seat-height and speed, stride length, knee FA-IC, ankle FA-IC, hip ROM-PP, vertical ground reaction force (VGRF), and anterior posterior ground reaction force (APGRF). Speed, hip ROM-PP, VGRF and APGRF increased as the seat-height was lowered. This effect diminished when the seat-height was set below -40 mm. VGRF increased as the seat-height was lowered. The results suggest that the seat-height effect can be attributed to hip ROM-PP; therefore, optimal foot propulsion cannot be achieved when the seat height is set either too high or too low. Efficient foot propulsion of the wheelchair can be achieved by setting the seat height to lower leg length according to a combination of physical characteristics, such as the user's physical functions, leg muscles, and range of motion.

  13. A COMPARISON OF STATIC AND DYNAMIC OPTIMIZATION MUSCLE FORCE PREDICTIONS DURING WHEELCHAIR PROPULSION

    Science.gov (United States)

    Morrow, Melissa M.; Rankin, Jeffery W.; Neptune, Richard R.; Kaufman, Kenton R.

    2014-01-01

    The primary purpose of this study was to compare static and dynamic optimization muscle force and work predictions during the push phase of wheelchair propulsion. A secondary purpose was to compare the differences in predicted shoulder and elbow kinetics and kinematics and handrim forces. The forward dynamics simulation minimized differences between simulated and experimental data (obtained from 10 manual wheelchair users) and muscle co-contraction. For direct comparison between models, the shoulder and elbow muscle moment arms and net joint moments from the dynamic optimization were used as inputs into the static optimization routine. RMS errors between model predictions were calculated to quantify model agreement. There was a wide range of individual muscle force agreement that spanned from poor (26.4 % Fmax error in the middle deltoid) to good (6.4 % Fmax error in the anterior deltoid) in the prime movers of the shoulder. The predicted muscle forces from the static optimization were sufficient to create the appropriate motion and joint moments at the shoulder for the push phase of wheelchair propulsion, but showed deviations in the elbow moment, pronation-supination motion and hand rim forces. These results suggest the static approach does not produce results similar enough to be a replacement for forward dynamics simulations, and care should be taken in choosing the appropriate method for a specific task and set of constraints. Dynamic optimization modeling approaches may be required for motions that are greatly influenced by muscle activation dynamics or that require significant co-contraction. PMID:25282075

  14. Wheelchairs

    Science.gov (United States)

    ... and anti-tipping devices. Power wheelchairs have many advantages for kids who need them. Electronic controllers can ... cars — even compete in some special types of sports competitions. But they also must look for handicapped- ...

  15. A Novel AHRS Inertial Sensor-Based Algorithm for Wheelchair Propulsion Performance Analysis

    Directory of Open Access Journals (Sweden)

    Jonathan Bruce Shepherd

    2016-08-01

    Full Text Available With the increasing rise of professionalism in sport, athletes, teams, and coaches are looking to technology to monitor performance in both games and training in order to find a competitive advantage. The use of inertial sensors has been proposed as a cost effective and adaptable measurement device for monitoring wheelchair kinematics; however, the outcomes are dependent on the reliability of the processing algorithms. Though there are a variety of algorithms that have been proposed to monitor wheelchair propulsion in court sports, they all have limitations. Through experimental testing, we have shown the Attitude and Heading Reference System (AHRS-based algorithm to be a suitable and reliable candidate algorithm for estimating velocity, distance, and approximating trajectory. The proposed algorithm is computationally inexpensive, agnostic of wheel camber, not sensitive to sensor placement, and can be embedded for real-time implementations. The research is conducted under Griffith University Ethics (GU Ref No: 2016/294.

  16. Compensatory strategies during manual wheelchair propulsion in response to weakness in individual muscle groups: A simulation study.

    Science.gov (United States)

    Slowik, Jonathan S; McNitt-Gray, Jill L; Requejo, Philip S; Mulroy, Sara J; Neptune, Richard R

    2016-03-01

    The considerable physical demand placed on the upper extremity during manual wheelchair propulsion is distributed among individual muscles. The strategy used to distribute the workload is likely influenced by the relative force-generating capacities of individual muscles, and some strategies may be associated with a higher injury risk than others. The objective of this study was to use forward dynamics simulations of manual wheelchair propulsion to identify compensatory strategies that can be used to overcome weakness in individual muscle groups and identify specific strategies that may increase injury risk. Identifying these strategies can provide rationale for the design of targeted rehabilitation programs aimed at preventing the development of pain and injury in manual wheelchair users. Muscle-actuated forward dynamics simulations of manual wheelchair propulsion were analyzed to identify compensatory strategies in response to individual muscle group weakness using individual muscle mechanical power and stress as measures of upper extremity demand. The simulation analyses found the upper extremity to be robust to weakness in any single muscle group as the remaining groups were able to compensate and restore normal propulsion mechanics. The rotator cuff muscles experienced relatively high muscle stress levels and exhibited compensatory relationships with the deltoid muscles. These results underline the importance of strengthening the rotator cuff muscles and supporting muscles whose contributions do not increase the potential for impingement (i.e., the thoracohumeral depressors) and minimize the risk of upper extremity injury in manual wheelchair users. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Comparing the shoulder impingement kinematics between circular and pumping strokes in manual wheelchair propulsion.

    Science.gov (United States)

    Feng, Chi Kuang; Wei, Shun-Hwa; Chen, Wen-Yin; Lee, Hsuei-Chen; Yu, Chung-Huang

    2010-01-01

    The study aimed to investigate the glenohumeral kinematic difference between the circular and pumping strokes in manual wheelchair users. This is a repeated measures design with randomised testing conditions. We recruited 10 manual wheelchair users and asked them to perform both the pumping and circular strokes on a stationary roller system. We used the Zebris motion analysis system to collect the 3-dimension glenohumeral motion data. The pumping and the circular strokes were similar in the starting and ending positions in the sagittal plane. However, the pumping stroke started at a significantly larger abduction and internal rotation and ended with a significantly larger abduction and even larger internal rotation, it also traveled more ranges in all three planes and stayed longer in the combined positions of rotation/flexion and rotation/abduction as compared to the circular stroke. The circular stroke appeared more advantageous than the pumping technique in the injury prevention prospect because the latter involved more flexion, abduction and internal rotation of the shoulder, which could add more impingement stresses to the joint. Clinicians may need to prescribe proper wheelchair propulsion techniques for their clients to avoid accumulating impingement stresses in the shoulder joints.

  18. Effects of visual feedback-induced variability on motor learning of handrim wheelchair propulsion.

    Directory of Open Access Journals (Sweden)

    Marika T Leving

    Full Text Available It has been suggested that a higher intra-individual variability benefits the motor learning of wheelchair propulsion. The present study evaluated whether feedback-induced variability on wheelchair propulsion technique variables would also enhance the motor learning process. Learning was operationalized as an improvement in mechanical efficiency and propulsion technique, which are thought to be closely related during the learning process.17 Participants received visual feedback-based practice (feedback group and 15 participants received regular practice (natural learning group. Both groups received equal practice dose of 80 min, over 3 weeks, at 0.24 W/kg at a treadmill speed of 1.11 m/s. To compare both groups the pre- and post-test were performed without feedback. The feedback group received real-time visual feedback on seven propulsion variables with instruction to manipulate the presented variable to achieve the highest possible variability (1st 4-min block and optimize it in the prescribed direction (2nd 4-min block. To increase motor exploration the participants were unaware of the exact variable they received feedback on. Energy consumption and the propulsion technique variables with their respective coefficient of variation were calculated to evaluate the amount of intra-individual variability.The feedback group, which practiced with higher intra-individual variability, improved the propulsion technique between pre- and post-test to the same extent as the natural learning group. Mechanical efficiency improved between pre- and post-test in the natural learning group but remained unchanged in the feedback group.These results suggest that feedback-induced variability inhibited the improvement in mechanical efficiency. Moreover, since both groups improved propulsion technique but only the natural learning group improved mechanical efficiency, it can be concluded that the improvement in mechanical efficiency and propulsion technique do not

  19. Wheelchair Propulsion Biomechanics in Junior Basketball Players: A Method for the Evaluation of the Efficacy of a Specific Training Program.

    Science.gov (United States)

    Bergamini, Elena; Morelli, Francesca; Marchetti, Flavia; Vannozzi, Giuseppe; Polidori, Lorenzo; Paradisi, Francesco; Traballesi, Marco; Cappozzo, Aurelio; Delussu, Anna Sofia

    2015-01-01

    As participation in wheelchair sports increases, the need of quantitative assessment of biomechanical performance indicators and of sports- and population-specific training protocols has become central. The present study focuses on junior wheelchair basketball and aims at (i) proposing a method to identify biomechanical performance indicators of wheelchair propulsion using an instrumented in-field test and (ii) developing a training program specific for the considered population and assessing its efficacy using the proposed method. Twelve athletes (10 M, 2 F, age = 17.1 ± 2.7 years, years of practice = 4.5 ± 1.8) equipped with wheelchair- and wrist-mounted inertial sensors performed a 20-metre sprint test. Biomechanical parameters related to propulsion timing, progression force, and coordination were estimated from the measured accelerations and used in a regression model where the time to complete the test was set as dependent variable. Force- and coordination-related parameters accounted for 80% of the dependent variable variance. Based on these results, a training program was designed and administered for three months to six of the athletes (the others acting as control group). The biomechanical indicators proved to be effective in providing additional information about the wheelchair propulsion technique with respect to the final test outcome and demonstrated the efficacy of the developed program.

  20. Wheelchair Propulsion Biomechanics in Junior Basketball Players: A Method for the Evaluation of the Efficacy of a Specific Training Program

    Directory of Open Access Journals (Sweden)

    Elena Bergamini

    2015-01-01

    Full Text Available As participation in wheelchair sports increases, the need of quantitative assessment of biomechanical performance indicators and of sports- and population-specific training protocols has become central. The present study focuses on junior wheelchair basketball and aims at (i proposing a method to identify biomechanical performance indicators of wheelchair propulsion using an instrumented in-field test and (ii developing a training program specific for the considered population and assessing its efficacy using the proposed method. Twelve athletes (10 M, 2 F, age = 17.1 ± 2.7 years, years of practice = 4.5 ± 1.8 equipped with wheelchair- and wrist-mounted inertial sensors performed a 20-metre sprint test. Biomechanical parameters related to propulsion timing, progression force, and coordination were estimated from the measured accelerations and used in a regression model where the time to complete the test was set as dependent variable. Force- and coordination-related parameters accounted for 80% of the dependent variable variance. Based on these results, a training program was designed and administered for three months to six of the athletes (the others acting as control group. The biomechanical indicators proved to be effective in providing additional information about the wheelchair propulsion technique with respect to the final test outcome and demonstrated the efficacy of the developed program.

  1. Wheelchair Propulsion Biomechanics in Junior Basketball Players: A Method for the Evaluation of the Efficacy of a Specific Training Program

    Science.gov (United States)

    Bergamini, Elena; Morelli, Francesca; Marchetti, Flavia; Vannozzi, Giuseppe; Polidori, Lorenzo; Paradisi, Francesco; Traballesi, Marco; Cappozzo, Aurelio

    2015-01-01

    As participation in wheelchair sports increases, the need of quantitative assessment of biomechanical performance indicators and of sports- and population-specific training protocols has become central. The present study focuses on junior wheelchair basketball and aims at (i) proposing a method to identify biomechanical performance indicators of wheelchair propulsion using an instrumented in-field test and (ii) developing a training program specific for the considered population and assessing its efficacy using the proposed method. Twelve athletes (10 M, 2 F, age = 17.1 ± 2.7 years, years of practice = 4.5 ± 1.8) equipped with wheelchair- and wrist-mounted inertial sensors performed a 20-metre sprint test. Biomechanical parameters related to propulsion timing, progression force, and coordination were estimated from the measured accelerations and used in a regression model where the time to complete the test was set as dependent variable. Force- and coordination-related parameters accounted for 80% of the dependent variable variance. Based on these results, a training program was designed and administered for three months to six of the athletes (the others acting as control group). The biomechanical indicators proved to be effective in providing additional information about the wheelchair propulsion technique with respect to the final test outcome and demonstrated the efficacy of the developed program. PMID:26543852

  2. Relationship between resultant force at the pushrim and the net shoulder joint moments during manual wheelchair propulsion in elderly persons.

    Science.gov (United States)

    Desroches, Guillaume; Aissaoui, Rachid; Bourbonnais, Daniel

    2008-06-01

    To determine the relationship between the resultant force at the pushrim and the net shoulder joint moments during manual wheelchair propulsion in elderly persons. Convenience sample. Motion analysis laboratory. Older manual wheelchair users (N=14; age, 68.2+/-5.2y) were tested. Kinematic and kinetic data were collected during manual wheelchair propulsion at a speed between 0.96 and 1.01m/s for 10 seconds and at a power output around 22.4W on a wheelchair ergometer. Net shoulder joint moments were computed with an inverse dynamic model. The mechanical use of the forces at the pushrim and the mechanical fraction of effective force were measured during propulsion. Mechanical use and mechanical fraction of effective force had a positive and significant correlation with the net internal (Pplane, and the net flexion (Pplane. The results suggest that because the resultant force at the pushrim has a greater tangential component and a greater proportion of the maximal voluntary force, most of the net moments around the shoulder are higher. Thus the optimal way of propelling, from a mechanical point of view (ie, tangential), may not be advantageous for manual wheelchair users.

  3. The influence of wheelchair propulsion hand pattern on upper extremity muscle power and stress.

    Science.gov (United States)

    Slowik, Jonathan S; Requejo, Philip S; Mulroy, Sara J; Neptune, Richard R

    2016-06-14

    The hand pattern (i.e., full-cycle hand path) used during manual wheelchair propulsion is frequently classified as one of four distinct hand pattern types: arc, single loop, double loop or semicircular. Current clinical guidelines recommend the use of the semicircular pattern, which is based on advantageous levels of broad biomechanical metrics implicitly related to the demand placed on the upper extremity (e.g., lower cadence). However, an understanding of the influence of hand pattern on specific measures of upper extremity muscle demand (e.g., muscle power and stress) is needed to help make such recommendations, but these quantities are difficult and impractical to measure experimentally. The purpose of this study was to use musculoskeletal modeling and forward dynamics simulations to investigate the influence of the hand pattern used on specific measures of upper extremity muscle demand. The simulation results suggest that the double loop and semicircular patterns produce the most favorable levels of overall muscle stress and total muscle power. The double loop pattern had the lowest full-cycle and recovery-phase upper extremity demand but required high levels of muscle power during the relatively short contact phase. The semicircular pattern had the second-lowest full-cycle levels of overall muscle stress and total muscle power, and demand was more evenly distributed between the contact and recovery phases. These results suggest that in order to decrease upper extremity demand, manual wheelchair users should consider using either the double loop or semicircular pattern when propelling their wheelchairs at a self-selected speed on level ground. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Shoulder kinetics during start-up and propulsion with a manual wheelchair within the initial phase of uninstructed training.

    Science.gov (United States)

    Hybois, Samuel; Siegel, Alice; Bascou, Joseph; Eydieux, Nicolas; Vaslin, Philippe; Pillet, Hélène; Fodé, Pascale; Sauret, Christophe

    2018-01-01

    Wheelchair locomotion is constraining for the upper limbs and involves a set of motor tasks that need to be learnt by a novice user. To understand this integration process, we investigated the evolution of shoulder kinetics during start-up and propulsion within the initial phase of low-intensity uninstructed training. Seventeen novice able-bodied subjects performed a 120-min uninstructed practice distributed over 4 weeks. During the initial and final sessions, upper limbs kinematics and hand-rim kinetics were continuously collected. Inverse kinematics and dynamics coupled to a three-dimensional linked-segment model were used to compute shoulder net moments. Participants increased the speed of the wheelchair with practice. In average, an increase of shoulder net moments and mechanical work during the push phase was observed. Conversely, during the recovery phase, participants slightly increased shoulder power but maintained a similar level of shoulder loading. However, individual evolutions allowed the definition of two groups defined as: "increasers", who increased shoulder loading and mechanical work versus "decreasers", who managed to limit shoulder loading while improving the wheelchair speed. These findings underline that individual adaptation strategies are essential to take into account when designing a rehabilitation protocol for wheelchair users. Implications for Rehabilitation The learning process of manual wheelchair locomotion is essential for the assimilation of motor tasks leading individuals to select their propulsion technique. Novice users display different learning strategies: some people increase shoulder loading very early but others spontaneously manage to increase the wheelchair speed while maintaining a constant level of shoulder loading. Wheelchair rehabilitation programs should be individualized to take into account the subject-specific learning strategy.

  5. Three dimensional upper extremity motion during manual wheelchair propulsion in men with different levels of spinal cord injury.

    Science.gov (United States)

    Newsam, C J; Rao, S S; Mulroy, S J; Gronley, J K; Bontrager, E L; Perry, J

    1999-12-01

    This investigation compared three dimensional upper extremity motion during wheelchair propulsion in persons with 4 levels of spinal cord injury: low paraplegia (n=17), high paraplegia (n=19), C7 tetraplegia (n=16), and C6 tetraplegia (n=17). Upper extremity motion was recorded as subjects manually propelled a wheelchair mounted on a stationary ergometer. For all motions measured, subjects with paraplegia had similar patterns suggesting that the wheelchair backrest adequately stabilizes the trunk in the absence of abdominal musculature. Compared with paraplegic subjects, those with tetraplegia differed primarily in the strategy used to contact the wheel. This was most evident among subjects with C6 tetraplegia who had greater wrist extension and less forearm pronation.

  6. Early motor learning changes in upper-limb dynamics and shoulder complex loading during handrim wheelchair propulsion.

    Science.gov (United States)

    Vegter, Riemer J K; Hartog, Johanneke; de Groot, Sonja; Lamoth, Claudine J; Bekker, Michel J; van der Scheer, Jan W; van der Woude, Lucas H V; Veeger, Dirkjan H E J

    2015-03-10

    To propel in an energy-efficient manner, handrim wheelchair users must learn to control the bimanually applied forces onto the rims, preserving both speed and direction of locomotion. Previous studies have found an increase in mechanical efficiency due to motor learning associated with changes in propulsion technique, but it is unclear in what way the propulsion technique impacts the load on the shoulder complex. The purpose of this study was to evaluate mechanical efficiency, propulsion technique and load on the shoulder complex during the initial stage of motor learning. 15 naive able-bodied participants received 12-minutes uninstructed wheelchair practice on a motor driven treadmill, consisting of three 4-minute blocks separated by two minutes rest. Practice was performed at a fixed belt speed (v = 1.1 m/s) and constant low-intensity power output (0.2 W/kg). Energy consumption, kinematics and kinetics of propulsion technique were continuously measured. The Delft Shoulder Model was used to calculate net joint moments, muscle activity and glenohumeral reaction force. With practice mechanical efficiency increased and propulsion technique changed, reflected by a reduced push frequency and increased work per push, performed over a larger contact angle, with more tangentially applied force and reduced power losses before and after each push. Contrary to our expectations, the above mentioned propulsion technique changes were found together with an increased load on the shoulder complex reflected by higher net moments, a higher total muscle power and higher peak and mean glenohumeral reaction forces. It appears that the early stages of motor learning in handrim wheelchair propulsion are indeed associated with improved technique and efficiency due to optimization of the kinematics and dynamics of the upper extremity. This process goes at the cost of an increased muscular effort and mechanical loading of the shoulder complex. This seems to be associated with an

  7. The biomechanics of wheelchair propulsion in individuals with and without upper-limb impairment

    National Research Council Canada - National Science Library

    Finley, Margaret A; Rasch, Elizabeth K; Keyser, Randall E; Rodgers, Mary M

    2004-01-01

    We used an instrumented wheelchair ergometer and 3D motion analysis system to collect joint kinematic and temporal data, as well as hand rim and joint kinetics, in 47 manual wheelchair users (MWCUs...

  8. The effect of resultant force at the pushrim on shoulder kinetics during manual wheelchair propulsion: a simulation study.

    Science.gov (United States)

    Desroches, Guillaume; Aissaoui, Rachid; Bourbonnais, Daniel

    2008-04-01

    The aim of this study was to determine, by simulation on real data, the effect of modifying the direction or effectiveness of a given force amplitude on the load sustained by the shoulder estimated by joint forces and moments. Kinematics and kinetics data were recorded on 14 manual wheelchair users 68.2+/-5.2 years for 10 s at sub-maximal speed (0.96-1.01 m/s). The simulation consisted in modifying force effectiveness at the pushrim while maintaining the same initial force amplitude. Shoulder kinetics were computed for simulated resultant forces from radial to tangent directions and also for initial force effectiveness. The results show that as the force was simulated tangent to the wheel, there was a significant increase in the average proximal and anterior shoulder joint forces. Also, significant increases in average internal rotation, flexion in the sagittal and horizontal plane moments were reported. Higher shoulder kinetics could accelerate the onset of fatigue and increase the risk of injury. A single-case analysis revealed an improvement window for force effectiveness ( approximately 10%) in which shoulder kinetics were not substantially increased. Our results provide useful information on what would happen to shoulder kinetics if we were able to teach manual wheelchair users to modify their force pattern at the pushrim. The results suggest that for an elderly population, it is not wise to aim at producing a mechanically optimal resultant force at the pushrim (i.e., tangent). Smaller increases of the initial force effectiveness would be preferable.

  9. Effect of fore-aft seat position on shoulder demands during wheelchair propulsion: part 2. An electromyographic analysis.

    Science.gov (United States)

    Gutierrez, Dee D; Mulroy, Sara J; Newsam, Craig J; Gronley, Joanne K; Perry, Jacquelin

    2005-01-01

    Shoulder pain is common in persons with complete spinal cord injury. Adjustment of the wheelchair-user interface has been thought to reduce shoulder demands. The purpose of this study was to quantify the effect of seat fore-aft position on shoulder muscle activity during wheelchair propulsion. Shoulder electromyography (EMG) was recorded while 13 men with paraplegia propelled a wheelchair in the following 2 seat positions: (a) shoulder joint center aligned with the wheel axle (anterior) and (b) shoulder joint center 8 cm posterior to the wheel axle (posterior) in 3 test conditions (free, fast, and graded). Duration of EMG activity and median and peak intensities were compared. During free propulsion, the median EMG intensity of all muscles was similar between anterior and posterior seat positions. The major propulsive muscles (pectoralis major and anterior deltoid) demonstrated significant reductions in their median and peak intensities in the posterior seat position. Pectoralis major median intensity was significantly reduced in the posterior position during fast (52% vs 66% maximal muscle test [MMT]) and graded (41 % vs 49% MMT) conditions, and peak intensity was significantly reduced in the free condition (29% vs 52% MMT) and the fast condition (103% vs 150% MMT). Anterior deltoid intensity was significantly reduced in the posterior position during fast propulsion only (26% vs 31% MMT). For all muscles, EMG duration was similar between positions in all test conditions. Reduction in the intensity of the primary push phase muscles (pectoralis major and anterior deltoid) during high-demand activities of fast and graded propulsion may reduce the potential for shoulder muscle fatigue and injuries.

  10. Low-Intensity Wheelchair Training in Inactive People with Long-Term Spinal Cord Injury: A Randomized Controlled Trial on Propulsion Technique.

    Science.gov (United States)

    van der Scheer, Jan W; de Groot, Sonja; Vegter, Riemer J K; Hartog, Johanneke; Tepper, Marga; Slootman, Hans; Veeger, DirkJan H E J; van der Woude, Lucas H V

    2015-11-01

    The objective of this study was to investigate the effects of a low-intensity wheelchair training on propulsion technique in inactive people with long-term spinal cord injury. Participants in this multicenter nonblinded randomized controlled trial were inactive manual wheelchair users with spinal cord injury for at least 10 yrs (N = 29), allocated to exercise (n = 14) or no exercise. The 16-wk training consisted of wheelchair treadmill propulsion at 30%-40% heart rate reserve or equivalent in rate of perceived exertion, twice a week, 30 mins per session. Propulsion technique was assessed at baseline as well as after 8, 16, and 42 wks during two submaximal treadmill-exercise blocks using a measurement wheel attached to a participant's own wheelchair. Changes over time between the groups were analyzed using Mann-Whitney U tests on difference scores (P < 0.05/3). Data of 16 participants could be analyzed (exercise: n = 8). Significant differences between the exercise and control groups were only found in peak force after 8 wks (respective medians, -20 N vs. 1 N; P = 0.01; r(u) = 0.78). Significant training effects on propulsion technique were not found in this group. Perhaps, substantial effects require a higher intensity or frequency. Investigating whether more effective and feasible interventions exist might help reduce the population's risk of upper-body joint damage during daily wheelchair propulsion.

  11. Relationship Between Hand Contact Angle and Shoulder Loading During Manual Wheelchair Propulsion by Individuals with Paraplegia.

    Science.gov (United States)

    Requejo, Philip Santos; Mulroy, Sara J; Ruparel, Puja; Hatchett, Patricia E; Haubert, Lisa Lighthall; Eberly, Valerie J; Gronley, JoAnne K

    2015-01-01

    Shoulder loading during manual wheelchair propulsion (WCP) contributes to the development of shoulder pain in individuals with spinal cord injury (SCI). To use regression analysis to investigate the relationships between the hand contact angle (location of the hand on the pushrim at initial contact and release during the push phase of the WCP cycle) with propulsion characteristics, pushrim forces, and shoulder kinetics during WCP in individuals with paraplegia. Biomechanical data were collected from 222 individuals (198 men and 24 women) with paraplegia from SCI during WCP on a stationary ergometer at a self-selected speed. The average age of participants was 34.7 years (±9.3), mean time since SCI was 9.3 years (±6.1), and average body weight was 74.4 kg (±15.9). The majority (n = 127; 56%) of participants had lower level paraplegia (T8 to L5) and 95 (42%) had high paraplegia (T2 to T7). Increased push arc (mean = 75.3°) was associated with greater velocity (R = 0.384, P < .001) and cycle distance (R = 0.658, P < .001) and reduced cadence (R = -0.419, P <.001). Initial contact angle and hand release angles were equally associated with cycle distance and cadence, whereas a more anterior release angle was associated with greater velocity (R = 0.372, P < .001). When controlling for body weight, a more posterior initial contact angle was associated with greater posterior shoulder net joint force (R = 0.229, P = .001) and greater flexor net joint moment (R = 0.204, P = .002), whereas a more anterior hand release angle was significantly associated with increased vertical (R = 0.270, P < .001) and greater lateral (R = .293, P < .001) pushrim forces; greater shoulder net joint forces in all 3 planes - posterior (R = 0.164, P = .015), superior (R = 0.176, P = .009), and medial (R = 0.284, P < .001); and greater external rotator (R = 0.176, P = .009) and adductor (R = 0.259, P = .001) net joint moments. Current clinical practice guidelines recommend using long, smooth

  12. Effect of fore-aft seat position on shoulder demands during wheelchair propulsion: part 1. A kinetic analysis.

    Science.gov (United States)

    Mulroy, Sara J; Newsam, Craig J; Gutierrez, Dee D; Requejo, Philip; Gronley, JoAnne K; Haubert, Lisa Lighthall; Perry, Jacquelin

    2005-01-01

    The highly repetitive and weight-bearing nature of wheelchair (WC) propulsion has been associated with shoulder pain among persons with spinal cord injury (SCI). Manipulation of WC seat position is believed to reduce the overall demand of WC propulsion. The objective of this investigation was to document the effect of fore-aft seat position on shoulder joint kinetics. Thirteen men with complete motor paraplegia propelled a test WC in 2 fore-aft seat positions during free, fast, and graded conditions. The seat-anterior position aligned the glenohumeral joint with the wheel axle and the seat-posterior position moved the glenohumeral joint 8 cm posteriorly. The right wheel of the test chair was instrumented to measure forces applied to the pushrim. An inverse dynamics algorithm was applied to calculate shoulder joint forces, external moments, and powers. For all test conditions, the superior component of the shoulder joint resultant force was significantly lower in the seat-posterior position. During graded propulsion, the posterior component of the shoulder joint force was significantly higher with the seat posterior. Peak shoulder joint moments and power were similar during free and fast propulsion. During graded propulsion, the seat-posterior position displayed increased internal rotation moment, decreased sagittal plane power absorption, and increased transverse plane power generation. This investigation provides objective support that a posterior seat position reduces the superior component of the shoulder joint resultant force. Consequently, this intervention potentially diminishes the risk for impingement of subacromial structures.

  13. Effects of Seated Postural Stability and Trunk and Upper Extremity Strength on Performance during Manual Wheelchair Propulsion Tests in Individuals with Spinal Cord Injury: An Exploratory Study

    Directory of Open Access Journals (Sweden)

    Dany H. Gagnon

    2016-01-01

    Full Text Available Objectives. To quantify the association between performance-based manual wheelchair propulsion tests (20 m propulsion test, slalom test, and 6 min propulsion test, trunk and upper extremity (U/E strength, and seated reaching capability and to establish which ones of these variables best predict performance at these tests. Methods. 15 individuals with a spinal cord injury (SCI performed the three wheelchair propulsion tests prior to discharge from inpatient SCI rehabilitation. Trunk and U/E strength and seated reaching capability with unilateral hand support were also measured. Bivariate correlation and multiple linear regression analyses allowed determining the best determinants and predictors, respectively. Results. The performance at the three tests was moderately or strongly correlated with anterior and lateral flexion trunk strength, anterior seated reaching distance, and the shoulder, elbow, and handgrip strength measures. Shoulder adductor strength-weakest side explained 53% of the variance on the 20-meter propulsion test-maximum velocity. Shoulder adductor strength-strongest side and forward seated reaching distance explained 71% of the variance on the slalom test. Handgrip strength explained 52% of the variance on the 6-minute propulsion test. Conclusion. Performance at the manual wheelchair propulsion tests is explained by a combination of factors that should be considered in rehabilitation.

  14. Projection of the point of force application onto a palmar plane of the hand during wheelchair propulsion.

    Science.gov (United States)

    Cooper, R A; Robertson, R N; VanSickle, D P; Boninger, M L; Shimada, S D

    1996-09-01

    The objective of this study was to develop and test a method for projecting the pushrim point of force application (PFA) onto a palmar plane model of the hand. Repetitive wheelchair use often leads to hand and wrist pain or injury. The manner by which the hands grasp the pushrim and how the forces and moments applied to the pushrim are directed may contribute to the high incidence of pain and injury. The projections of the PFA onto the palmar surface model of the hand reside primarily within zone II. These results are in agreement with previous studies which have assumed the PFA to be coincident with one of the metacarpophalangeal (MP) joints. However, the results from three subjects show different PFA patterns within the palmar surface of the hand which can be related to each subject's propulsion pattern, and the PFA is not focused at a single MP joint. Projection of the world coordinates of the four hand marker system onto the palmar plane show the resolution to be within 3 mm, or one half the diameter of the passive reflective markers. The errors in the planar model assumption were greatest for the second and fifth MP markers. This was expected because as the hand grasp changes these markers do not remain coplanar. The results of this study indicate that new knowledge about how forces are applied by the hand onto the pushrim can be obtained using this method. This technical note provides insight into understanding the details within the kinetics of wheelchair propulsion and describes a technique for estimation of the PFA on the palmar surface of the hand. This technical note provides initial results from three different wheelchair users.

  15. Relation between median and ulnar nerve function and wrist kinematics during wheelchair propulsion.

    Science.gov (United States)

    Boninger, Michael L; Impink, Bradley G; Cooper, Rory A; Koontz, Alicia M

    2004-07-01

    To investigate the relation between median and ulnar nerve health and wrist kinematics in wheelchair users. Case series. Biomechanics laboratory and electrodiagnostic laboratory at a Veterans Health Administration medical center and a university hospital, respectively. Thirty-five people with spinal cord injury who use manual wheelchairs. Subjects propelled their own wheelchair on a dynamometer at 0.9 and 1.8m/s. Bilateral biomechanic data were obtained by using force and moment sensing pushrims and a kinematic system. Bilateral median and ulnar nerve conduction studies were also completed. Wrist flexion, extension, radial and ulnar deviation peaks, and ranges of motion (ROMs) as related to median and ulnar motor and sensory amplitudes. A secondary analysis included peak pushrim forces and moments and stroke frequency. There was a significant, positive correlation between flexion and extension ROM and both ulnar motor amplitude (r=.383, P<.05) and median motor amplitude (r=.361, P<.05). Contrary to our hypothesis, subjects using a greater ROM showed better nerve function than subjects propelling with a smaller ROM. Subjects using a larger ROM used less force and fewer strokes to propel their wheelchairs at a given speed. It is possible that long, smooth strokes may benefit nerve health in manual wheelchair users.

  16. Mechanical advantage in wheelchair lever propulsion : effect on physical strain and efficiency

    NARCIS (Netherlands)

    van der Woude, L H; Botden, E; Vriend, I; Veeger, DirkJan (H. E. J.)

    In this experimental study on a prototype lever-propelled wheelchair, the effect of a range of mechanical advantages (MA) on physical strain, oxygen uptake, energy cost, mechanical efficiency, stroke frequency and perceived exertion was examined. Nine out of 10 male nonwheelchair users successfully

  17. Manual wheelchair propulsion by people with hemiplegia: within-participant comparisons of forward versus backward techniques.

    Science.gov (United States)

    Charbonneau, Rebecca; Kirby, R Lee; Thompson, Kara

    2013-09-01

    To test the hypotheses that people with hemiplegia using arms and legs to propel their wheelchairs perform better backward than forward and prefer the backward direction. Within-participant cross-sectional design. Manual wheelchair users (N=18) with hemiplegia caused by stroke, a sample of convenience. Rehabilitation center. Participants each performed 9 skills from the Wheelchair Skills Test (WST 4.1)-4 low-rolling-resistance skills (rolls 10m, turns 90° while moving, rolls 2m across 5° side slope, descends 5cm level change) and 5 high-rolling-resistance skills (ascends 5° incline, rolls 2m on soft surface, gets over 15-cm pothole, gets over 2-cm threshold, ascends 5cm level change)-in both the forward and backward directions, in random order. Total percentage capacity scores from the modified WST 4.1, success rates for individual skills, and responses from an orally administered questionnaire regarding direction preferences. The mean ± SD total WST 4.1 capacity scores were 53%±26% in the forward direction and 76%±30% in the backward direction (Pskills, there were no clinically significant differences (≥20%) between forward and backward success rates. For the 5 high-rolling-resistance skills, the success rates were 33% to 50% higher in the backward direction. Participants preferred the forward direction for low-rolling-resistance skills and the backward direction for high-rolling-resistance skills. Wheelchair skills that involve high rolling resistance are performed more successfully in the backward than the forward direction, and participants prefer the backward direction for such skills. These findings have implications for wheelchair selection and skills training. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. A Novel AHRS Inertial Sensor-Based Algorithm for Wheelchair Propulsion Performance Analysis

    OpenAIRE

    Jonathan Bruce Shepherd; Tomohito Wada; David Rowlands; Daniel Arthur James

    2016-01-01

    With the increasing rise of professionalism in sport, athletes, teams, and coaches are looking to technology to monitor performance in both games and training in order to find a competitive advantage. The use of inertial sensors has been proposed as a cost effective and adaptable measurement device for monitoring wheelchair kinematics; however, the outcomes are dependent on the reliability of the processing algorithms. Though there are a variety of algorithms that have been proposed to monito...

  19. Wheelchair Propulsion Biomechanics in Junior Basketball Players: A Method for the Evaluation of the Efficacy of a Specific Training Program

    National Research Council Canada - National Science Library

    Bergamini, Elena; Morelli, Francesca; Marchetti, Flavia; Vannozzi, Giuseppe; Polidori, Lorenzo; Paradisi, Francesco; Traballesi, Marco; Cappozzo, Aurelio; Delussu, Anna Sofia

    2015-01-01

      As participation in wheelchair sports increases, the need of quantitative assessment of biomechanical performance indicators and of sports- and population-specific training protocols has become central...

  20. Feasibility for developing cardiovascular exercise recommendations for persons with motor-complete paraplegia based on manual wheelchair propulsion; A protocol and preliminary data.

    Science.gov (United States)

    McCormick, Zachary L; Lynch, Meaghan; Liem, Brian; Jacobs, Geneva; Hwang, Peter; Hornby, Thomas George; Rydberg, Leslie; Roth, Elliot

    2016-01-01

    The Center for Disease Control, American Heart Association, and American College of Sports Medicine recommendations for duration and intensity of exercise are based on the amount of energy expenditure required to maintain cardiovascular health in able body individuals; 1000 Kilocalories (Kcals) per week of energy expenditure has been demonstrated to achieve this effect. Manual wheelchair propulsion (MWP) represents a practical and accessible form of exercise for individuals with paraplegia. To describe a method to determine the duration of MWP required to expend 1000 Kcals, when performed by individuals with paraplegia due to motor-complete spinal cord injury (SCI). Cross-sectional study. Rehabilitation Research Laboratory. Sixteen adults with motor complete T3-T12 paraplegia (body mass index paraplegia > 3 months). Not applicable. Indirect calorimetry during MWP was measured in order to calculate caloric expenditure per minute. These data were used to calculate the number of minutes of MWP required to expend 1000 Kcal in one week. During MWP, participants expended 3.3 ± 1.0 Kcal/minute. Based on this figure, 1000 Kcal of energy expenditure in one week would require 303 minutes of MWP per week, or 43.3 minutes per day, 7 days per week. Our data suggest that it is feasible to create a practical and accessible exercise recommendation based on manual wheelchair propulsion for individuals with paraplegia due to motor-complete SCI. Larger studies are needed in order to develop accurate exercise recommendations for persons with SCI.

  1. Computer-controlled wheelchair ergometer

    NARCIS (Netherlands)

    R. Niesing (Ruud); F. Eijskoot (F.); R. Kranse (Ries); A.H. den Ouden (A.); J. Storm (J.); D. Veeger (Dirkjan); L.H. van der Woude (Luc); C.J. Snijders (Chris)

    1990-01-01

    textabstractA new wheelchair ergometer has been designed in which a combination of realistic simulation of wheelchair propulsion-with adjustable parameters for rolling resistance, air drag, wind speed and slope-and force measurement has been realised. The static solution enables the measurement of

  2. Early motor learning changes in upper-limb dynamics and shoulder complex loading during handrim wheelchair propulsion

    NARCIS (Netherlands)

    Vegter, Riemer J K; Hartog, Johanneke; de Groot, Sonja; Lamoth, Claudine J; Bekker, Michel J; van der Scheer, Jan W; van der Woude, Lucas H V; Veeger, Dirkjan H E J

    2015-01-01

    BACKGROUND: To propel in an energy-efficient manner, handrim wheelchair users must learn to control the bimanually applied forces onto the rims, preserving both speed and direction of locomotion. Previous studies have found an increase in mechanical efficiency due to motor learning associated with

  3. Early motor learning changes in upper-limb dynamics and shoulder complex loading during handrim wheelchair propulsion

    NARCIS (Netherlands)

    Vegter, Riemer J. K.; Hartog, Johanneke; de Groot, Sonja; Lamoth, Claudine J.; Bekker, Michel J.; van der Scheer, Jan W.; van der Woude, Lucas H. V.; Veeger, Dirkjan H. E. J.

    2015-01-01

    Background: To propel in an energy-efficient manner, handrim wheelchair users must learn to control the bimanually applied forces onto the rims, preserving both speed and direction of locomotion. Previous studies have found an increase in mechanical efficiency due to motor learning associated with

  4. Early motor learning changes in upper-limb dynamics and shoulder complex loading during handrim wheelchair propulsion

    NARCIS (Netherlands)

    Vegter, R.J.K.; Hartog, J.; De Groot, S.; Lamoth, C.J.; Bekker, M.J.; Van der Scheer, J.W.; Van der Woude, L.H.V.; Veeger, H.E.J.

    2015-01-01

    Background To propel in an energy-efficient manner, handrim wheelchair users must learn to control the bimanually applied forces onto the rims, preserving both speed and direction of locomotion. Previous studies have found an increase in mechanical efficiency due to motor learning associated with

  5. Trunk and Shoulder Kinematic and Kinetic and Electromyographic Adaptations to Slope Increase during Motorized Treadmill Propulsion among Manual Wheelchair Users with a Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Dany Gagnon

    2015-01-01

    Full Text Available The main objective was to quantify the effects of five different slopes on trunk and shoulder kinematics as well as shoulder kinetic and muscular demands during manual wheelchair (MWC propulsion on a motorized treadmill. Eighteen participants with spinal cord injury propelled their MWC at a self-selected constant speed on a motorized treadmill set at different slopes (0°, 2.7°, 3.6°, 4.8°, and 7.1°. Trunk and upper limb movements were recorded with a motion analysis system. Net shoulder joint moments were computed with the forces applied to the handrims measured with an instrumented wheel. To quantify muscular demand, the electromyographic activity (EMG of the pectoralis major (clavicular and sternal portions and deltoid (anterior and posterior fibers was recorded during the experimental tasks and normalized against maximum EMG values obtained during static contractions. Overall, forward trunk flexion and shoulder flexion increased as the slope became steeper, whereas shoulder flexion, adduction, and internal rotation moments along with the muscular demand also increased as the slope became steeper. The results confirm that forward trunk flexion and shoulder flexion movement amplitudes, along with shoulder mechanical and muscular demands, generally increase when the slope of the treadmill increases despite some similarities between the 2.7° to 3.6° and 3.6° to 4.8° slope increments.

  6. Dynamics of wheelchair basketball.

    Science.gov (United States)

    Coutts, K D

    1992-02-01

    A sport model wheelchair instrumented with a portable computer and a switch activated with each half revolution of a rear wheel was used to record serial time and distance data on two subjects (1 male, 1 female) during a portion of a basketball game. These and two additional subjects (1 male, 1 female) also completed a series of coast down and maximal sprint trials on the basketball court. The drag force while coasting was positively related to the mass of the subject, and the male subjects had a higher maximal speed, acceleration, force, and power output in the sprint trials. During the wheelchair basketball game, it was estimated that 64% of the time was spent in propulsive action and 36% in braking activity. Projections for a complete 40 minute game indicated that both subjects would travel about 5 km at an average speed of 2 m.s-1 and attain a peak speed of 4 m.s-1. Plots of speed and power vs time showed the intermittent nature of playing wheelchair basketball. The greater amount of propulsive work (52.6 vs 37.5 kJ) and braking ("negative") work (43.9 vs 30.8 kJ) in a game for the male subject can be related to the male's higher body mass and wheelchair drag force.

  7. Energy Cost of Lower Body Dressing, Pop-Over Transfers, and Manual Wheelchair Propulsion in People with Paraplegia Due to Motor-Complete Spinal Cord Injury.

    Science.gov (United States)

    Lynch, Meaghan M; McCormick, Zachary; Liem, Brian; Jacobs, Geneva; Hwang, Peter; Hornby, Thomas George; Rydberg, Leslie; Roth, Elliot J

    2015-01-01

    Energy required for able-bodied individuals to perform common activities is well documented, whereas energy associated with daily activities among people with spinal cord injury (SCI) is less understood. To determine energy expended during several basic physical tasks specific to individuals with paraplegia due to motor-complete SCI. Sixteen adults with motor-complete SCI below T2 level and duration of paraplegia greater than 3 months were included. Oxygen consumption (VO2), caloric expenditure, and heart rate were measured at rest and while participants performed lower body dressing (LBD), pop-over transfers (POTs), and manual wheelchair propulsion (MWP) at a self-selected pace. These data were used to calculate energy expenditure in standard metabolic equivalents (METs), as defined by 1 MET = 3.5 mL O2/kg/min, and in SCI METs using the conversion 1 SCI MET = 2.7 mL O2/kg/min. VO2 at rest was 3.0 ± 0.9 mL O2/kg/min, which equated to 0.9 ± 0.3 standard METs and 1.1 ± 0.4 SCI METs in energy expenditure. LBD required 3.2 ± 0.7 METs and 4.1 ± 0.9 SCI METs; POTs required 3.4 ± 1.0 METs and 4.5 ± 1.3 SCI METs; and MWP required 2.4 ± 0.6 METs and 3.1 ± 0.7 SCI METs. Resting VO2 for adults with motor-complete paraplegia is 3.0 mL O2/kg/min, which is lower than standard resting VO2 in able-bodied individuals. Progressively more energy is required to perform MWP, LBD, and POTs, respectively. Use of the standard METs formula may underestimate the level of intensity an individual with SCI uses to perform physical activities.

  8. Shoulder Pain and Cycle to Cycle Kinematic Spatial Variability during Recovery Phase in Manual Wheelchair Users: A Pilot Investigation

    OpenAIRE

    Jayaraman, Chandrasekaran; Moon, Yaejin; Rice, Ian M.; Hsiao Wecksler, Elizabeth T.; Beck, Carolyn L.; Sosnoff, Jacob J.

    2014-01-01

    Wheelchair propulsion plays a significant role in the development of shoulder pain in manual wheelchair users (MWU). However wheelchair propulsion metrics related to shoulder pain are not clearly understood. This investigation examined intra-individual kinematic spatial variability during semi-circular wheelchair propulsion as a function of shoulder pain in MWU. Data from 10 experienced adult MWU with spinal cord injury (5 with shoulder pain; 5 without shoulder pain) were analyzed in this stu...

  9. Is energy expenditure taken into account in human sub-maximal jumping? - a simulation study

    NARCIS (Netherlands)

    Vanrenterghem, J.; Bobbert, M.F.; Casius, L.J.R.; de Clercq, D.

    2008-01-01

    This paper presents a simulation study that was conducted to investigate whether the stereotyped motion pattern observed in human sub-maximal jumping can be interpreted from the perspective of energy expenditure. Human sub-maximal vertical countermovement jumps were compared to jumps simulated with

  10. A new design for an old concept of wheelchair pushrim.

    Science.gov (United States)

    Medola, Fausto Orsi; Fortulan, Carlos Alberto; Purquerio, Benedito de Moraes; Elui, Valeria Meirelles Carril

    2012-05-01

    Report on the development of an ergonomic manual wheelchair pushrim and evaluate the user's perception of the quality of the device. Based on anthropometric features and ergonomic concepts, a new wheelchair pushrim was designed, and a prototype was manufactured in polyurethane, using the rapid prototyping technique and serial production of parts by molding. The prototype was tested by a sample of wheelchair users, who rated the perceived quality of the device after testing both the new and conventional pushrims in a wheelchair propulsion experimental protocol. The new ergonomic pushrim was found to be, in general, better than the conventional round tube pushrim. Specifically, experienced wheelchair users found the new wheelchair pushrim better in terms of easy and comfortable propulsion, braking and maneuvering of the wheelchair, and appearance. The new wheelchair pushrim provides a proper fit for the hands due to its ergonomic design and its polyurethane composition, making wheelchair propulsion easier and more comfortable than the conventional wheelchair pushrim. Assistive technology devices should be design based on ergonomic concepts that involve less effort and offer greater comfort for the user. [Box: see text].

  11. Computer-controlled wheelchair ergometer.

    Science.gov (United States)

    Niesing, R; Eijskoot, F; Kranse, R; den Ouden, A H; Storm, J; Veeger, H E; van der Woude, L H; Snijders, C J

    1990-07-01

    A new wheelchair ergometer has been designed in which a combination of realistic simulation of wheelchair propulsion--with adjustable parameters for rolling resistance, air drag, wind speed and slope--and force measurement has been realised. The static solution enables the measurement of physiological and kinesiological parameters. All data from force transducers in seat and backrest, torque transducers in the wheels and force transducers in the wheelframes as well as the acquired speed are sampled in a data-acquisition system. An offline curve processor allows the acquired data to be processed with standard or custom-programmed routines. Preliminary results have been added and are discussed.

  12. The ergonomics of wheelchair configuration for optimal performance in the wheelchair court sports.

    Science.gov (United States)

    Mason, Barry S; van der Woude, Lucas H V; Goosey-Tolfrey, Victoria L

    2013-01-01

    Optimizing mobility performance in wheelchair court sports (basketball, rugby and tennis) is dependent on a combination of factors associated with the user, the wheelchair and the interfacing between the two. Substantial research has been attributed to the wheelchair athlete yet very little has focused on the role of the wheelchair and the wheelchair-user combination. This article aims to review relevant scientific literature that has investigated the effects of wheelchair configuration on aspects of mobility performance from an ergonomics perspective. Optimizing performance from an ergonomics perspective requires a multidisciplinary approach. This has resulted in laboratory-based investigations incorporating a combination of physiological and biomechanical analyses to assess the efficiency, health/safety and comfort of various wheelchair configurations. To a lesser extent, field-based testing has also been incorporated to determine the effects of wheelchair configuration on aspects of mobility performance specific to the wheelchair court sports. The available literature has demonstrated that areas of seat positioning, rear wheel camber, wheel size and hand-rim configurations can all influence the ergonomics of wheelchair performance. Certain configurations have been found to elevate the physiological demand of wheelchair propulsion, others have been associated with an increased risk of injury and some have demonstrated favourable performance on court. A consideration of all these factors is required to identify optimal wheelchair configurations. Unfortunately, a wide variety of different methodologies have immerged between studies, many of which are accompanied by limitations, thus making the identification of optimal configurations problematic. When investigating an area of wheelchair configuration, many studies have failed to adequately standardize other areas, which has prevented reliable cause and effect relationships being established. In addition, a large

  13. Mechanical load on the upper extremity during wheelchair activities

    NARCIS (Netherlands)

    Van Drongelen, Stefan; Van der Woude, Lucas H; Janssen, Thomas W; Angenot, Edmond L; Chadwick, Edward K; Veeger, DirkJan (H. E. J.)

    OBJECTIVE: To determine the net moments on the glenohumeral joint and elbow joint during wheelchair activities. DESIGN: Kinematics and external forces were measured during wheelchair activities of daily living (level propulsion, riding on a slope, weight-relief lifting, reaching, negotiating a curb)

  14. Mechanical load on the upper extremity during wheelchair activities

    NARCIS (Netherlands)

    van Drongelen, S.; van der Woude, L.H.V.; Janssen, T.W.J.; Angenot, E.D.L.; Chadwick, E.K.J.; Veeger, H.E.J.

    2005-01-01

    Objective: To determine the net moments on the glenohumeral joint and elbow joint during wheelchair activities. Design: Kinematics and external forces were measured during wheelchair activities of daily living (level propulsion, riding on a slope, weight-relief lifting, reaching, negotiating a curb)

  15. Ultrasonographic median nerve changes after a wheelchair sporting event.

    Science.gov (United States)

    Impink, Bradley G; Boninger, Michael L; Walker, Heather; Collinger, Jennifer L; Niyonkuru, Christian

    2009-09-01

    To investigate the acute median nerve response to intense wheelchair propulsion by using ultrasonography and to examine the relationship between carpal tunnel syndrome (CTS) signs and symptoms and the acute median nerve response. Case series. Research room at the National Veterans Wheelchair Games. Manual wheelchair users (N=28) competing in wheelchair basketball. Ultrasound images collected before and after a wheelchair basketball game. Median nerve cross-sectional area, flattening ratio, and swelling ratio and changes in these after activity. Comparison of median nerve characteristics and patient characteristics between participants with and without positive physical examination findings and with and without symptoms of CTS. Significant changes in median nerve ultrasound characteristics were noted after activity. The group as a whole showed a significant decrease in cross-sectional area at the radius of 4.05% (P=.023). Participants with positive physical examinations showed significantly different (P=.029) and opposite changes in swelling ratio compared with the normal group. Subjects with CTS symptoms had a significantly (P=.022) greater duration of wheelchair use (17.1 y) compared with the asymptomatic participants (9 y). Manual wheelchair propulsion induces acute changes in median nerve characteristics that can be visualized by using ultrasound. Studying the acute median nerve response may be useful for optimizing various interventions, such as wheelchair set up or propulsion training, to decrease both acute and chronic median nerve damage and the likelihood of developing CTS.

  16. The effects of three days of sub-maximal-intensity mountain biking ...

    African Journals Online (AJOL)

    The effects of three days of sub-maximal-intensity mountain biking on sleep. ... South African Journal of Sports Medicine ... The sleep of the mountain bikers was assessed both subjectively (visual analogue scales and sleep questionnaires) and objectively (activity data logger) on each night of mountain biking and for seven ...

  17. Biomechanics of Pediatric Manual Wheelchair Mobility

    Science.gov (United States)

    Slavens, Brooke A.; Schnorenberg, Alyssa J.; Aurit, Christine M.; Tarima, Sergey; Vogel, Lawrence C.; Harris, Gerald F.

    2015-01-01

    Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting, and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the handrim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces, and moments of 14 children with spinal cord injury (SCI) during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI. PMID:26442251

  18. Biomechanics of Pediatric Manual Wheelchair Mobility.

    Science.gov (United States)

    Slavens, Brooke A; Schnorenberg, Alyssa J; Aurit, Christine M; Tarima, Sergey; Vogel, Lawrence C; Harris, Gerald F

    2015-01-01

    Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting, and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the handrim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces, and moments of 14 children with spinal cord injury (SCI) during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI.

  19. The Effect of Acute Sub-Maximal Endurance Exercise on Serum Angiogenic Indices in Sedentary Men

    Directory of Open Access Journals (Sweden)

    Kamal Ranjbar

    2014-06-01

    Full Text Available Background: Endurance training increases capillary density of skeletal muscle, but the molecular mechanism of this process is not yet clear. Therefore, the purpose of this study was to investigate the effect of acute sub maximal endurance exercise on serum levels of vascular endothelial growth factor (VEGF and matrix metaloproteinases 2 and 9 (MMP-2 and MMP-9 in sedentary men. Materials and Methods: Twelve healthy men (22.37±2.30 years, BMI=23.16 ±2.61 kg/mP 2 P participated in this study. Subjects exercised for 1h at 70% of VOR2R max, 3 days after the VOR2R max determination. Antecubital vein blood was collected at rest, immediately and 2h after the exercise. Serum VEGF, MMP-2 and MMP-9 were measured by ELISA methods5T. Results: Serum levels of VEGF and MMP-2 decreased immediately after the exercise. 2 hours after the exercise, serum levels of VEGF remained at a lower level but serum MMP-2 returned to its basal level. Also, serum levels of MMP-9 did not change significantly in response to exercise5T. Conclusion: Acute sub-maximal endurance exercise decreased the main factors involved in development of capillary density in sedentary men. This might to due to the fact that, sub maximal exercise could not provide the two main stimulating factors of angiogenesis, i.e. Shear stress and hypoxia. It could also be explained by the fact that the mechanism of development of capillary network following regular endurance training is different from that following an acute exercise5T.5T

  20. Achilles tendinopathy alters stretch shortening cycle behaviour during a sub-maximal hopping task.

    Science.gov (United States)

    Debenham, James R; Travers, Mervyn J; Gibson, William; Campbell, Amity; Allison, Garry T

    2016-01-01

    To describe stretch shortening cycle behaviour of the ankle and lower limb in patients with Achilles tendinopathy (AT) and establish differences with healthy volunteers. Between-subjects case-controlled. Fifteen patients with AT (mean age 41.2±12.7 years) and 11 healthy volunteers (CON) (mean age 23.2±6.7 years) performed sub-maximal single-limb hopping on a custom built sledge-jump system. Using 3D motion analysis and surface EMG, temporal kinematic (lower limb stiffness, ankle angle at 80ms pre-contact, ankle angle at contact, peak ankle angle, ankle stretch amplitude) and EMG measures (onset, offset and peak times relative to contact) were captured. Data between AT and CON were compared statistically using a linear mixed model. Patients with AT exhibited significantly increased lower limb stiffness when compared to healthy volunteers (pbehaviour during sub-maximal hopping when compared with healthy volunteers. Patients with AT hop with greater lower limb stiffness, in a greater degree of ankle dorsiflexion and have a greater stretch amplitude. Likewise, delayed muscle activity is evident. These findings have implications in terms of informing the understanding of the pathoaetiology and management of AT. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  1. [Sub-maximal aerobic capacity and quality of life of patients with rheumatoid arthritis].

    Science.gov (United States)

    Lataoui, S; Belghali, S; Zeglaoui, H; Bouajina, E; Ben Saad, H

    2017-01-01

    Studies about sub-maximal aerobic capacity of patients with rheumatoid arthritis are scarce. To assess the sub-maximal aerobic capacity of these patients through the 6-min walk test, estimated age of the "muscular and cardiorespiratory" chain. Thirty-seven consecutive patients (aged 20 to 60 years) with newly diagnosed rheumatoid arthritis will be included. Non-inclusion criteria will be: use of drugs (e.g.; methotrexate, beta-blockers), orthopaedic or rheumatologic conditions (other than rheumatoid arthritis) that may alter walking ability and recent infections. Exclusion criteria will be: 6-min walking test contra-indications and imperfect performance of the required lung function and walking maneuvers. Signs of walking intolerance will be: test interruption, distance ≤lower limit of normal, dyspnea score ≥5/10 (visual analogue scale) at the end of the test, haemoglobin oxygen saturation (SpO2) drop ≥5%, cardiac frequency at the end of the test ≤60% of maximum predicted. An estimated "muscular and cardiorespiratory chain" age higher than the chronological one will be considered as a sign of accelerated ageing. A high percentage of patients suffering from rheumatoid arthritis would show evidences of walking limitation and accelerated "muscular and cardiorespiratory chain" ageing. There would be a significant correlation between the walking test and clinical, biological, radiological and pulmonary function data and the patients' quality-of-life status. Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  2. A qualitative examination of wheelchair configuration for optimal mobility performance in wheelchair sports : a pilot study

    NARCIS (Netherlands)

    Mason, Barry S.; Porcellato, Lorna; van der Woude, Lucas H. V.; Goosey-Tolfrey, Victoria L.

    Objective: To examine wheelchair athletes' perceptions of wheelchair configuration in relation to aspects of mobility performance. Methods: Nine elite wheelchair athletes from wheelchair basketball, wheelchair rugby and wheelchair tennis were interviewed using a semi-structured format. Interview

  3. Keep on rolling: functional evaluation of power-assisted wheelchair use

    NARCIS (Netherlands)

    Kloosterman, Marieke

    2016-01-01

    Prototype of newly developed power-assisted wheelchair wheels were evaluated to determine their potential alleviating value on shoulder load, daily activities and participation compared to hand-rim wheelchair propulsion. Five research questions were answered: 1. What is the current knowledge of

  4. Improving Mobility Performance in Wheelchair Basketball

    NARCIS (Netherlands)

    Veeger, Thom T.J.; De Witte, Annemarie M H; Berger, Monique A M; van der Slikke, Rienk M A; Veeger, Dirkjan H E J; Hoozemans, Marco J M

    2017-01-01

    OBJECTIVE: This study aimed to investigate which characteristics of athlete, wheelchair and athlete-wheelchair interface are the best predictors of wheelchair basketball mobility performance. DESIGN: Sixty experienced wheelchair basketball players performed a wheelchair mobility performance test to

  5. Design History and Advantages of a New Lever-Propelled Wheelchair Prototype

    Directory of Open Access Journals (Sweden)

    Ahmad Rifai Sarraj

    2011-09-01

    Full Text Available Wheelchair propulsion has been reported to be responsible for musculoskeletal pain in the upper extremities. Epidemiological studies have shown a high prevalence of shoulder complaints in paraplegic and quadriplegic spinal cord injured (SCI people. It has been argued that the high incidence of shoulder complaints in SCI was the result of the weight‐bearing or propulsion function of the upper extremity in those subjects. This work aimed at proposing an alternative wheelchair propulsion technique based on the levers' system. The interface prototype‐users, the wheelchair skills evaluation, the oxygen uptake and the cardiac frequency are investigated by an objective and subjective studies. Our prototype is designed to be an attempt in the field of disabled athletes having some advantages of a non‐ conventional manual wheelchair propulsion technique, avoiding complications induced by the conventional one.

  6. Design History and Advantages of a New Lever-Propelled Wheelchair Prototype

    Directory of Open Access Journals (Sweden)

    Ahmad Rifai Sarraj

    2011-08-01

    Full Text Available Wheelchair propulsion has been reported to be responsible for musculoskeletal pain in the upper extremities. Epidemiological studies have shown a high prevalence of shoulder complaints in paraplegic and quadriplegic spinal cord injured (SCI people. It has been argued that the high incidence of shoulder complaints in SCI was the result of the weight-bearing or propulsion function of the upper extremity in those subjects. This work aimed at proposing an alternative wheelchair propulsion technique based on the levers' system. The interface prototype-users, the wheelchair skills evaluation, the oxygen uptake and the cardiac frequency are investigated by an objective and subjective studies. Our prototype is designed to be an attempt in the field of disabled athletes having some advantages of a non-conventional manual wheelchair propulsion technique, avoiding complications induced by the conventional one.

  7. Evaluation of Pediatric Manual Wheelchair Mobility Using Advanced Biomechanical Methods

    Directory of Open Access Journals (Sweden)

    Brooke A. Slavens

    2015-01-01

    Full Text Available There is minimal research of upper extremity joint dynamics during pediatric wheelchair mobility despite the large number of children using manual wheelchairs. Special concern arises with the pediatric population, particularly in regard to the longer duration of wheelchair use, joint integrity, participation and community integration, and transitional care into adulthood. This study seeks to provide evaluation methods for characterizing the biomechanics of wheelchair use by children with spinal cord injury (SCI. Twelve subjects with SCI underwent motion analysis while they propelled their wheelchair at a self-selected speed and propulsion pattern. Upper extremity joint kinematics, forces, and moments were computed using inverse dynamics methods with our custom model. The glenohumeral joint displayed the largest average range of motion (ROM at 47.1° in the sagittal plane and the largest average superiorly and anteriorly directed joint forces of 6.1% BW and 6.5% BW, respectively. The largest joint moments were 1.4% body weight times height (BW × H of elbow flexion and 1.2% BW × H of glenohumeral joint extension. Pediatric manual wheelchair users demonstrating these high joint demands may be at risk for pain and upper limb injuries. These evaluation methods may be a useful tool for clinicians and therapists for pediatric wheelchair prescription and training.

  8. Biomechanics of pediatric manual wheelchair mobility

    Directory of Open Access Journals (Sweden)

    Brooke A. Slavens

    2015-09-01

    Full Text Available Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the hand-rim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces and moments of 14 children with spinal cord injury (SCI during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI.

  9. Pushrim kinetics during advanced wheelchair skills in manual wheelchair users with spinal cord injury.

    Science.gov (United States)

    Nagy, Jennifer; Winslow, Amy; Brown, Jessica M; Adams, Lisa; O'Brien, Kathleen; Boninger, Michael; Nemunaitis, Gregory

    2012-01-01

    To assess the peak force during wheelchair propulsion of individuals with spinal cord injury propelling over obstacles from the Wheelchair Skills Test. Twenty-three individuals with spinal cord injury (SCI) who are full-time manual wheelchair users were included in this prospective study. A SmartWheel (Three Rivers Holdings, LLC) was used to analyze each push while subjects negotiated standardized obstacles used in the Wheelchair Skills Test, including tile, carpet, soft surface, 5° and 10° ramps, 2 cm, 5 cm, and 15 cm curbs. When the peak forces of the advanced skills were compared to level 10 m tile/10 m carpet, there was a statistically significant increase in all peak forces (P value ranged from .0001 to .0268). It is well documented that a large number of individuals with SCI develop upper limb pain. One of the recommendations to preserve the upper limb is to minimize force during repetitive tasks. Advanced wheelchair skills require an increase in force to accomplish. The increase in forces ranged from 18% to 130% over that required for level 10 m tile/10 m carpet.

  10. Stability Ball Sitting versus Chair Sitting During Sub-maximal Arm Ergometry.

    Science.gov (United States)

    Marks, Charles R C; Hylland, Kristina E; Terrell, Jacob

    It was predicted that sitting on a stability ball during arm ergometry would elevate cardiovascular parameters when compared to sitting on a chair and that this would be associated with greater recruitment of trunk and leg skeletal muscles. Open-circuit spirometry, videotaping, blood pressure, heart rate, and EMG were conducted during rest and four minute stages of 15 W, 30 W, and 45 W using a Monark arm ergometer. Twenty-six apparently healthy adults exercised twice, once sitting on a stability ball and the other sitting on a chair (order randomized), with 45 to 60 minutes of rest between. ANOVA for repeated measures and paired-t testing were used for analysis. Oxygen consumption was significantly 10 to 16% higher during exercise while sitting on the stability ball. There were no significant differences between sitting modes for heart rate, SBP, and DBP. Also, resting and exercise rectus femoris and 45 W external oblique EMGs were significantly higher on the stability ball. Finally, the knee was significantly more extended with the feet farther apart and more forward on the stability ball. The stability ball significantly elevates oxygen consumption during sub-maximal arm cranking without significantly increasing heart rate or blood pressure and this is associated with increased thigh muscle activation and lower leg repositioning.

  11. Effect of Wheelchair Frame Material on Users' Mechanical Work and Transmitted Vibration

    Science.gov (United States)

    Aissaoui, Rachid

    2014-01-01

    Wheelchair propulsion exposes the user to a high risk of shoulder injury and to whole-body vibration that exceeds recommendations of ISO 2631-1:1997. Reducing the mechanical work required to travel a given distance (WN-WPM, weight-normalized work-per-meter) can help reduce the risk of shoulder injury, while reducing the vibration transmissibility (VT) of the wheelchair frame can reduce whole-body vibration. New materials such as titanium and carbon are used in today's wheelchairs and are advertised to improve both parameters, but current knowledge on this matter is limited. In this study, WN-WPM and VT were measured simultaneously and compared between six folding wheelchairs (1 titanium, 1 carbon, and 4 aluminium). Ten able-bodied users propelled the six wheelchairs on three ground surfaces. Although no significant difference of WN-WPM was found between wheelchairs (P < 0.1), significant differences of VT were found (P < 0.05). The carbon wheelchair had the lowest VT. Contrarily to current belief, the titanium wheelchair VT was similar to aluminium wheelchairs. A negative correlation between VT and WN-WPM was found, which means that reducing VT may be at the expense of increasing WN-WPM. Based on our results, use of carbon in wheelchair construction seems promising to reduce VT without increasing WN-WPM. PMID:25276802

  12. Measures of energy expenditure and comfort in an ESP wheelchair: a controlled trial using hemiplegic users'.

    Science.gov (United States)

    Mandy, Anne; Lesley, Samuel

    2009-05-01

    The aim of this pilot study using hemiplegic subjects was to measure energy expenditure, hand position and ride comfort, in a standard dual handrim Sunrise Breezy wheelchair compared to one modified with a novel ergonomic self-propelled steering (ESP) mechanism kit. A previous study by Mandy et al. (Disabil Rehabil Assist Technol 2007;2:255-260) reported that the attachment of the ESP kit to a standard Sunrise Breezy wheelchair provided a more ergonomically efficient mechanism for wheelchair steering and propulsion for non-disabled individuals. Thirteen hemiplegic stroke users participated in a repeated measures trial by driving two manual wheelchairs--a standard manual dual handrim wheelchair and one fitted with the ESP steering conversion kit. Wheelchairs were randomly assigned, to participants who drove each wheelchair around a designated circuit. Oxygen consumption, carbon dioxide and heart rate were measured as indicators of ergonomic efficiency using a Cosmed analyser. Comfort for each wheelchair was measured using a validated questionnaire. Oxygen consumption (O(2)mls/min) and exhaled carbon dioxide (CO(2)mls/min) were significantly lower in the modified wheelchair (p ESP (p ESP (p ESP conversion kit transforms a standard Sunrise Breezy wheelchair into one that is ergonomically more efficient and comfortable for hemiplegic subjects.

  13. Field-based physiological testing of wheelchair athletes.

    Science.gov (United States)

    Goosey-Tolfrey, Victoria L; Leicht, Christof A

    2013-02-01

    The volume of literature on field-based physiological testing of wheelchair sports, such as basketball, rugby and tennis, is considerably smaller when compared with that available for individuals and team athletes in able-bodied (AB) sports. In analogy to the AB literature, it is recognized that performance in wheelchair sports not only relies on fitness, but also sport-specific skills, experience and technical proficiency. However, in contrast to AB sports, two major components contribute towards 'wheeled sports' performance, which are the athlete and the wheelchair. It is the interaction of these two that enable wheelchair propulsion and the sporting movements required within a given sport. Like any other athlete, participants of wheelchair sports are looking for efficient ways to train and/or analyse their technique and fitness to improve their performance. Consequently, laboratory and/or field-based physiological monitoring tools used at regular intervals at key time points throughout the year must be considered to help with training evaluation. The present review examines methods available in the literature to assess wheelchair sports fitness in a field-based environment, with special attention on outcome variables, validity and reliability issues, and non-physiological influences on performance. It also lays out the context of field-based testing by providing details about the Paralympic court sports and the impacts of a disability on sporting performance. Due to the limited availability of specialized equipment for testing wheelchair-dependent participants in the laboratory, the adoption of field-based testing has become the preferred option by team coaches of wheelchair athletes. An obvious advantage of field-based testing is that large groups of athletes can be tested in less time. Furthermore, athletes are tested in their natural environment (using their normal sports wheelchair set-up and floor surface), potentially making the results of such testing

  14. Wheelchair basketball quantification.

    Science.gov (United States)

    Gil-Agudo, Angel; Del Ama-Espinosa, Antonio; Crespo-Ruiz, Beatriz

    2010-02-01

    Classification systems are one of the key elements in sports for people with disability, including wheelchair basketball. Further scientific studies to validate classification systems are needed. This article describes the most relevant research, with emphasis on biomechanics.

  15. Design and development of solar power-assisted manual/electric wheelchair.

    Science.gov (United States)

    Chien, Chi-Sheng; Huang, Tung-Yung; Liao, Tze-Yuan; Kuo, Tsung-Yuan; Lee, Tzer-Min

    2014-01-01

    Wheelchairs are an essential assistive device for many individuals with injury or disability. Manual wheelchairs provide a relatively low-cost solution to the mobility needs of such individuals. Furthermore, they provide an effective means of improving the user's cardiopulmonary function and upper-limb muscle strength. However, manual wheelchairs have a loss gross mechanical efficiency, and thus the risk of user fatigue and upper-limb injury is increased. Electric-powered wheelchairs reduce the risk of injury and provide a more convenient means of transportation. However, they have a large physical size and are relatively expensive. Accordingly, the present study utilizes a quality function deployment method to develop a wheelchair with a user-selectable manual/electric propulsion mode and an auxiliary solar power supply system. The auxiliary solar power supply increased the travel range of the wheelchair by approximately 26% compared with that of a wheelchair powered by battery alone. Moreover, the wheelchair has a modular design and can be disassembled and folded for ease of transportation or storage. Overall, the present results suggest that the proposed wheelchair provides an effective and convenient means of meeting the mobility needs of individuals with mobility difficulties.

  16. Assessment Of Physiological Cardio respiratory Parameters During Sub maximal Exercise On Acute Exposure To Normobaric Hypoxia In Healthy Young Males

    Directory of Open Access Journals (Sweden)

    Bipin K Shrestha

    2016-06-01

    Full Text Available To estimate changes in SBP, DBP, HR, RR and Lactate Level at Near Sea Level (NSL and at Simulated altitude (3000meters at rest and during sub-maximal exercise.Mean Resting values at NSL vs. Hypoxic Chamber were: SBP (1276vs1325mmHg, DBP (703vs786mmHg, HR (725vs806bpm, RR (254vs293/min and LL (2.10.35vs2.50.42mmol/l. Similarly, mean values at the end of exercise were: SBP (1529vs16913mmHg, DBP (836vs926mmHg, HR (13412vs1557bpm, RR (356vs516/min and LL (7.110.89vs8.011.03mmol/l.  A significant difference exists in mean resting values of SBP, DBP, HR and RR at NSL and on acute exposure to Normobaric Hypoxia. Sub-maximal exercise in hypoxic conditions appears to depend more on anaerobic metabolism and results in greater sympathetic activity. Keywords: Cardiorespiratory parameters, Normobaric hypoxia, Sub-maximal exercise, Near Sea Level

  17. Evaluation of selected sidewalk pavement surfaces for vibration experienced by users of manual and powered wheelchairs.

    Science.gov (United States)

    Cooper, Rory A; Wolf, Erik; Fitzgerald, Shirley G; Kellerher, Annmarie; Ammer, William; Boninger, Michael L; Cooper, Rosemarie

    2004-01-01

    Obstacles such as bumps, curb descents, and uneven driving surfaces cause vibrations that affect the wheelchair, and in turn, the wheelchair user. Chronic exposure can cause low-back pain, disk degeneration, and other harmful effects. Little research has been conducted to assess the vibrations experienced by wheelchair users. The purpose of this study was to conduct an evaluation of the vibration exposure during electric-powered wheelchair driving and mechanical energy requirements for manual wheelchair propulsion over selected sidewalk surfaces. The goal was to determine the criteria for a wheelchair-pedestrian access route that does not require excessive propulsive work or expose wheelchair users to potentially harmful vibrations. Ten unimpaired individuals participated in this study. Six sidewalk surfaces were tested. Measured variables included power of the acceleration per octave, mechanical work to propel over surfaces, peak acceleration, and frequency at which peak acceleration occurs. For both the manual and electric-powered wheelchair, at 1 m/s, significant differences were found in peak accelerations between the seat and footrest (P < 0.0001) and between the sidewalk surfaces (P = 0.004). The greatest risk for injury caused by shock and vibration exposure occurs at frequencies near the natural frequency of seated humans (4-15 Hz). The values for work required to propel over the surfaces tested were not statistically significantly different. Besides appearance and construction, the only distinguishing characteristic was surface roughness caused by the joints. When treating the poured concrete sidewalk as the standard, surfaces 2, 3, 5, and 6 compared most favorably in terms of vibration exposure, whereas surface 4 produced mixed results. Surfaces 2, 3, 5, and 6 yielded results that were similar to the poured concrete sidewalk and could be considered acceptable for wheelchair users. In conclusion, surfaces other than the traditional poured concrete can be

  18. EEG Controlled Wheelchair

    Directory of Open Access Journals (Sweden)

    Swee Sim Kok

    2016-01-01

    Full Text Available This paper describes the development of a brainwave controlled wheelchair. The main objective of this project is to construct a wheelchair which can be directly controlled by the brain without requires any physical feedback as controlling input from the user. The method employed in this project is the Brain-computer Interface (BCI, which enables direct communication between the brain and the electrical wheelchair. The best method for recording the brain’s activity is electroencephalogram (EEG. EEG signal is also known as brainwaves signal. The device that used for capturing the EEG signal is the Emotiv EPOC headset. This headset is able to transmit the EEG signal wirelessly via Bluetooth to the PC (personal computer. By using the PC software, the EEG signals are processed and converted into mental command. According to the mental command (e.g. forward, left... obtained, the output electrical signal is sent out to the electrical wheelchair to perform the desired movement. Thus, in this project, a computer software is developed for translating the EEG signal into mental commands and transmitting out the controlling signal wirelessly to the electrical wheelchair.

  19. Is any wheelchair better than no wheelchair? A Zimbabwean perspective

    Directory of Open Access Journals (Sweden)

    Surona Visagie

    2015-02-01

    Full Text Available Background: Within a rights-based paradigm, wheelchairs are essential in the promotion of user autonomy, dignity, freedom, inclusion and participation. Objectives: This paper aimed to describe a group of Zimbabwean wheelchair users’ satisfaction with wheelchairs, wheelchair services and wheelchair function. Method: A mixed method, descriptive study was done. Quantitative data was collected from 94 consecutively sampled wheelchair users, who accessed wheelchair services at 16 clinics in five Zimbabwean provinces between October 2013 and February 2014, using the Quebec User Evaluation of Satisfaction with Assistive Technology for adults and children and Functioning Every day with a Wheelchair questionnaire. Qualitative data were collected through two focus group discussions (22 participants and two case studies with participants purposively sampled from those who participated in the quantitative phase. Results: More than 60% of participants were dissatisfied with the following wheelchair features: durability (78.6%, weight (75.6%, ease of adjustment (69.1%, effectiveness (69.0%, safety (66.7%, reliability (66.7%, and meeting user needs (60.6%. Similarly, more than 66% of participants were dissatisfied with various services aspects: professional services (69.0%, follow-up (67.0%, and service delivery (68.3%. Although 60% of participants agreed that the wheelchair contributed to specific functions, more than 50% of participants indicated that the features of the wheelchair did not allow in- (53.2% and outdoor (52.7% mobility.Conclusion: Findings indicate high levels of dissatisfaction with wheelchair features and services, as well as mobility. It is recommended that policy and minimum service standards which incorporate evidence and good practice guidelines for wheelchair services and management of wheelchair donations are developed for Zimbabwe.

  20. Different types of compression clothing do not increase sub-maximal and maximal endurance performance in well-trained athletes.

    Science.gov (United States)

    Sperlich, Billy; Haegele, Matthias; Achtzehn, Silvia; Linville, John; Holmberg, Hans-Christer; Mester, Joachim

    2010-04-01

    Three textiles with increasing compressive surface were compared with non-compressive conventional clothing on physiological and perceptual variables during sub-maximal and maximal running. Fifteen well-trained endurance athletes (mean+/-s: age 27.1+/-4.8 years, VO(2max) 63.7+/-4.9 ml x min(-1) x kg(-1)) performed four sub-maximal (approximately 70% VO(2max)) and maximal tests with and without different compression stockings, tights, and whole-body compression suits. Arterial lactate concentration, oxygen saturation and partial pressure, pH, oxygen uptake, and ratings of muscle soreness were recorded before, during, and after all tests. In addition, we assessed time to exhaustion. Sub-maximal (P=0.22) and maximal oxygen uptake (P=0.26), arterial lactate concentration (P=0.16; 0.20), pH (P=0.23; 0.46), oxygen saturation (P=0.13; 0.26), and oxygen partial pressure (P=0.09; 0.20) did not differ between the types of clothing (effect sizes=0.00-0.45). Ratings of perceived exertion (P=0.10; 0.15), muscle soreness (P=0.09; 0.10) and time to exhaustion (P=0.16) were also unaffected by the different clothing (effect sizes=0.28-0.85). This was the first study to evaluate the effect on endurance performance of different types of compression clothing with increasing amounts of compressive surface. Overall, there were no performance benefits when using the compression garments.

  1. Improving mobility performance in wheelchair basketball

    NARCIS (Netherlands)

    Veeger, Thom T.J.; De Witte, Annemarie M.H.; Berger, Monique A.M.; van der Slikke, R.M.A.; Veeger, H.E.J.; Hoozemans, Marco J.M.

    2017-01-01

    Objectiev:
    This study aimed to investigate which characteristics of athlete, wheelchair and athlete-wheelchair interface are the best predictors of wheelchair basketball mobility performance.

    Design:
    Sixty experienced wheelchair basketball players performed a wheelchair mobility

  2. Improving Mobility Performance in Wheelchair Basketball

    NARCIS (Netherlands)

    Veeger, Thom T.J.; De Witte, Annemarie M.H.; Berger, Monique A.M.; van der Slikke, R.M.A.; Veeger, H.E.J.; Hoozemans, Marco J.M.

    2017-01-01

    Objectiev:
    This study aimed to investigate which characteristics of athlete, wheelchair and athlete-wheelchair interface are the best predictors of wheelchair basketball mobility performance.

    Design:
    Sixty experienced wheelchair basketball players performed a wheelchair mobility

  3. The health benefits and constraints of exercise therapy for wheelchair users: A clinical commentary

    Directory of Open Access Journals (Sweden)

    Terry J. Ellapen

    2017-01-01

    Full Text Available Background: There are approximately 1 billion people living with chronic lower limb disability, many of whom are wheelchair users.Objectives: Review cardiometabolic and neuromuscular risk profiles of wheelchair users, benefits of regular exercise and the causes of neuromuscular upper limb and hip injuries that hinder regular adherence.Method: Literature published between 2013 and 2017 was adopted according to the standard practices for systematic reviews (PRISMA through Crossref Metadata and Google Scholar searches. Individual paper quality was evaluated using a modified Downs and Black Appraisal Scale.Results: The literature search identified 16 600 papers which were excluded if they were non-English, non-peer-reviewed or published before 2013. Finally, 25 papers were accepted, indicating that sedentary wheelchair users have poor cardiometabolic risk profiles (PCMRP because of a lack of physical activity, limiting their quality of life, characterised by low self-esteem, social isolation and depression. Their predominant mode of physical activity is through upper limb exercises, which not only improves their cardiometabolic risk profiles but also precipitates neuromuscular upper limb overuse injuries. The primary cause of upper limb injuries was attributed to poor wheelchair propulsion related to incorrect chair setup and poor cardiorespiratory fitness.Conclusion: Wheelchair users have a high body mass index, body fat percentage and serum lipid, cholesterol and blood glucose concentrations. Empirical investigations illustrate exercise improves their PCMRP and cardiorespiratory fitness levels. Although literature encourages regular exercise, none discusses the need to individualise chair setup in order to eliminate wheelchair pathomechanics and upper limb neuromuscular injuries. Wheelchair users must be encouraged to consult a biokineticist or physiotherapist to review their wheelchair setup so as to eliminate possible incorrect manual wheelchair

  4. Concussions in wheelchair basketball.

    Science.gov (United States)

    Wessels, Karla K; Broglio, Steven P; Sosnoff, Jacob J

    2012-02-01

    To estimate the incidence rate of concussions in wheelchair basketball. Survey. Wheelchair basketball tournaments during the 2009 to 2010 season. Wheelchair basketball players (N=263) ranging in age from 18 to 60 years. Not applicable. Participants completed a survey on their concussion history including how many concussions they have sustained, how many days they refrained from physical activity because of injury, to whom they reported their injury, and reasons for not reporting an injury if they did not. Participants also provided demographic information about their disability, age, sex, and length of wheelchair use and sports participation. Within the sample of 263 wheelchair basketball players, 6.1% reported experiencing a concussion in the current season. Of those experiencing concussions during the current season, 44% did not report their concussion. Of those not reporting the incident, 67% did not because they did not want to be removed from physical activity. Analysis by sex indicated that 5.82% of the male athletes sustained a concussion during the current season, and 14.36% had sustained an injury during their athletic career. Female athletes, however, sustained concussions at a higher rate, with 6.67% having concussions during the current season and 30.6% during their athletic careers. Women were also 2.5 times more likely to sustain a concussion than men. Athletes were most likely to report their concussion to their coach (60% of concussed athletes). The current investigation was consistent with previous research in that women were more likely to sustain a concussion than men, and injury rates were similar to those in able-bodied basketball. Further work is needed in concussion assessment in persons with disability, as well as greater education concerning concussion in disability sports. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Análisis de la fuerza isométrica en la propulsión y tracción en slalom en silla de ruedas y su relación con el rendimiento y la clasificación funcional. [Isometric force in wheelchair slalom during traction and propulsion and their relationship with performance and functional classification].

    Directory of Open Access Journals (Sweden)

    Raúl Reina

    2013-10-01

    profiles of the Cerebral Palsy International Sports and Recreation Association, took part in the study (5 ♂ and 4 ♀. Participants performed two maximal isometric force tests (propulsion and traction with their competition wheelchairs in which maximum force (Fmax, average force (Fmed, execution time and time used to reach different Fmax percentages were recorded. In addition, participants carried out two specific performance tests: a 16 m linear sprint with an inversion door after 8 m; and two 4 m linear displacements with a zig-zag round trip. The measured variable was execution time using photocell gates. Significant differences were found between D3 and D4 in propulsion tests for Fmax (p = 0,007 and Fmean (p = 0,002, being this last one higher. Significant statistical differences were found between D2 and D3 in specific performance tests (inversion: p = 0,034 and zig-zag: p = 0,010, being D3 the quickest group. Results show a non-linear relationship between classification divisions and the performance.http://dx.doi.org/10.5232/ricyde2013.03402

  6. Not your parent's wheelchair.

    Science.gov (United States)

    Cox, Deborah I

    2004-01-01

    A pediatric wheelchair is indeed a smaller seating system mounted over a mobility base that helps a child get from point A to point B. The important thing to recognize is that the child is every day learning new things about how he or she fits in with the world. That child is making friends and exploring the playground and going to music or art class. He or she may be starting and ending the day with a parent, but midday is spent interacting with the school's bus driver, teachers, counselor, and therapists. It is the responsibility of the rehab specialist to make sure that, while using a wheelchair to get from point A to point B in all of these different settings and with all of these different people, that disability does not slow the child down.

  7. Shoulder pain and cycle to cycle kinematic spatial variability during recovery phase in manual wheelchair users: a pilot investigation.

    Directory of Open Access Journals (Sweden)

    Chandrasekaran Jayaraman

    Full Text Available Wheelchair propulsion plays a significant role in the development of shoulder pain in manual wheelchair users (MWU. However wheelchair propulsion metrics related to shoulder pain are not clearly understood. This investigation examined intra-individual kinematic spatial variability during semi-circular wheelchair propulsion as a function of shoulder pain in MWU. Data from 10 experienced adult MWU with spinal cord injury (5 with shoulder pain; 5 without shoulder pain were analyzed in this study. Participants propelled their own wheelchairs on a dynamometer at 3 distinct speeds (self-selected, 0.7 m/s, 1.1 m/s for 3 minutes at each speed. Motion capture data of the upper limbs were recorded. Intra-individual kinematic spatial variability of the steady state wrist motion during the recovery phase was determined using principal component analysis (PCA. The kinematic spatial variability was calculated at every 10% intervals (i.e at 11 interval points, from 0% to 100% along the wrist recovery path.Overall, spatial variability was found to be highest at the start and end of the recovery phase and lowest during the middle of the recovery path. Individuals with shoulder pain displayed significantly higher kinematic spatial variability than individuals without shoulder pain at the start (at 10% interval of the recovery phase (p<.004.Analysis of intra-individual kinematic spatial variability during the recovery phase of manual wheelchair propulsion distinguished between those with and without shoulder pain. Variability analysis of wheelchair propulsion may offer a new approach to monitor the development and rehabilitation of shoulder pain.

  8. Shoulder pain and cycle to cycle kinematic spatial variability during recovery phase in manual wheelchair users: a pilot investigation.

    Science.gov (United States)

    Jayaraman, Chandrasekaran; Moon, Yaejin; Rice, Ian M; Hsiao Wecksler, Elizabeth T; Beck, Carolyn L; Sosnoff, Jacob J

    2014-01-01

    Wheelchair propulsion plays a significant role in the development of shoulder pain in manual wheelchair users (MWU). However wheelchair propulsion metrics related to shoulder pain are not clearly understood. This investigation examined intra-individual kinematic spatial variability during semi-circular wheelchair propulsion as a function of shoulder pain in MWU. Data from 10 experienced adult MWU with spinal cord injury (5 with shoulder pain; 5 without shoulder pain) were analyzed in this study. Participants propelled their own wheelchairs on a dynamometer at 3 distinct speeds (self-selected, 0.7 m/s, 1.1 m/s) for 3 minutes at each speed. Motion capture data of the upper limbs were recorded. Intra-individual kinematic spatial variability of the steady state wrist motion during the recovery phase was determined using principal component analysis (PCA). The kinematic spatial variability was calculated at every 10% intervals (i.e at 11 interval points, from 0% to 100%) along the wrist recovery path. Overall, spatial variability was found to be highest at the start and end of the recovery phase and lowest during the middle of the recovery path. Individuals with shoulder pain displayed significantly higher kinematic spatial variability than individuals without shoulder pain at the start (at 10% interval) of the recovery phase (p<.004). Analysis of intra-individual kinematic spatial variability during the recovery phase of manual wheelchair propulsion distinguished between those with and without shoulder pain. Variability analysis of wheelchair propulsion may offer a new approach to monitor the development and rehabilitation of shoulder pain.

  9. Propulsion Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Propulsion Lab simulates field test conditions in a controlled environment, using standardized or customized test procedures. The Propulsion Lab's 11 cells can...

  10. Interaction effects of time of day and sub-maximal treadmill exercise on the main determinants of blood fluidity.

    Science.gov (United States)

    Ahmadizad, Sajad; Bassami, Minoo

    2010-01-01

    The purpose of this study was to investigate the effects of time of day on responses of the main determinants of blood rheology to acute endurance exercise. Ten healthy male subjects (age, 26.9 +/- 5.5 yr) performed two bouts of running at 65% of VO2peak for 45 min on a motorised treadmill in the morning (08:00 h) and evening (20:00 h), which were followed by 30 min recovery. The two exercise trials were performed in two separate days with 7 days intervening. Haemorheological variables were measured before, immediately after exercise and after recovery. Haematocrit, haemoglobin and RBC count were increased significantly (p evening trials and normalised following recovery, irrespective of time of day. Plasma viscosity increased significantly (F2,18 = 12.4, p exercise in both trials and returned to pre-exercise level at the end of recovery. Baseline values (p exercise were significantly affected by time of day. Neither a significant main effect of exercise nor a significant (p > 0.05) time-of-day effect was found for plasma proteins. It was concluded that sub-maximal running at 08:00 or 20:00 h does not induce different responses in the main determinant of blood rheology.

  11. Endurance and fatigue characteristics in the neck muscles during sub-maximal isometric test in patients with cervical radiculopathy.

    Science.gov (United States)

    Halvorsen, Marie; Abbott, Allan; Peolsson, Anneli; Dedering, Åsa

    2014-03-01

    The aim of the study was to compare myoelectric manifestation in neck muscle endurance and fatigue characteristics during sub-maximal isometric endurance test in patients with cervical radiculopathy and asymptomatic subjects. An additional aim was to explore associations between primary neck muscle endurance, myoelectric fatigability, and self-rated levels of fatigue, pain and subjective health measurements in patients with cervical radiculopathy. Muscle fatigue in the ventral and dorsal neck muscles was assessed in patients with cervical radiculopathy and in an asymptomatic group during an isometric neck muscle endurance test in prone and supine. 46 patients and 34 asymptomatic subjects participated. Surface electromyography signals were recorded from the sternocleidomastoid, cervical paraspinal muscles and upper and middle trapezius bilaterally during the endurance test. Subjective health measurements were assessed with questionnaires. The results showed altered neck muscle endurance in several of the muscles investigated with greater negative median frequency slope, greater variability, side imbalance, lower endurance time and higher experience of fatigue among the cervical radiculopathy patients compared with healthy subjects. Endurance times were significantly lower in both prone and in supine positions between the patients compared to asymptomatic subjects. During the neck muscle endurance test, fatigues in the upper trapezius muscles during the prone test and in the sternocleidomastoid muscles during the supine test were of more importance than self-perceived pain, fatigue, disability and kinesiophobia in predicting neck muscle endurance (NME). NME testing in the primary neck muscles seems to be an important factor to take into consideration in rehabilitation.

  12. Influence of wheel configuration on wheelchair basketball performance: wheel stiffness, tyre type and tyre orientation.

    Science.gov (United States)

    Mason, B S; Lemstra, M; van der Woude, L H V; Vegter, R; Goosey-Tolfrey, V L

    2015-04-01

    The aim of the current investigation was to explore the lateral stiffness of different sports wheelchair wheels available to athletes in 'new' and 'used' conditions and to determine the effect of (a) stiffness, (b) tyre type (clincher vs. tubular) and (c) tyre orientation on the physiological and biomechanical responses to submaximal and maximal effort propulsion specific to wheelchair basketball. Eight able-bodied individuals participated in the laboratory-based testing, which took place on a wheelchair ergometer at two fixed speeds (1.1 and 2.2 m s(-1)). Outcome measures were power output and physiological demand (oxygen uptake and heart rate). Three participants with experience of over-ground sports wheelchair propulsion also performed 2 × 20 m sprints in each wheel configuration. Results revealed that wheels differed significantly in lateral stiffness with the 'new' Spinergy wheel shown to be the stiffest (678.2 ± 102.1 N mm(-1)). However the effects of stiffness on physiological demand were minimal compared to tyre type whereby tubular tyres significantly reduced the rolling resistance and power output in relation to clincher tyres. Therefore tyre type (and subsequently inflation pressure) remains the most important aspect of wheel specification for athletes to consider and monitor when configuring a sports wheelchair. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  13. Mechanical energy and power flow analysis of wheelchair use with different camber settings.

    Science.gov (United States)

    Huang, Yueh-Chu; Guo, Lan-Yuen; Tsai, Chung-Ying; Su, Fong-Chin

    2013-04-01

    It has been suggested that minimisation of energy cost is one of the primary determinants of wheelchair designs. Wheel camber is one important parameter related to wheelchair design and its angle may affect usability during manual propulsion. However, there is little available literature addressing the effect of wheel camber on the mechanical energy or power flow involved in manual wheelchair propulsion. Twelve normal subjects (mean age, 22.3 years; SD, 1.6 years) participated in this study. A video-tracking system and an instrumented wheel were used to collect 3D kinematic and kinetic data. Wheel camber of 0° and 15° was chosen to examine the difference between mechanical power and power flow of the upper extremity during manual wheelchair propulsion. The work calculated from power flow and the discrepancy between the mechanical work and power flow work of upper extremity had significantly greater values with increased camber. The upper arm had a larger active muscle power compared with that in the forearm and hand segments. While propelling the increased camber, the magnitude of both the proximal and distal joint power and proximal muscle power was increased in all three segments. While the propelling wheel with camber not only needs a greater energy cost but also there is greater energy loss.

  14. Intelligent wheelchairs and assistant robots

    OpenAIRE

    Amat Girbau, Josep

    1998-01-01

    This work presents an overview over the main technological aids oriented to the rehabilitation of the physically disabled so that they can get some independence. These aids range from wheelchairs up to the assistant robots developed in the last years.

  15. Wheelchair control by head motion

    Directory of Open Access Journals (Sweden)

    Pajkanović Aleksandar

    2013-01-01

    Full Text Available Electric wheelchairs are designed to aid paraplegics. Unfortunately, these can not be used by persons with higher degree of impairment, such as quadriplegics, i.e. persons that, due to age or illness, can not move any of the body parts, except of the head. Medical devices designed to help them are very complicated, rare and expensive. In this paper a microcontroller system that enables standard electric wheelchair control by head motion is presented. The system comprises electronic and mechanic components. A novel head motion recognition technique based on accelerometer data processing is designed. The wheelchair joystick is controlled by the system’s mechanical actuator. The system can be used with several different types of standard electric wheelchairs. It is tested and verified through an experiment performed within this paper.

  16. From Wheelchair to Cane

    Science.gov (United States)

    Mayo, Amanda; Berbrayer, David

    2015-01-01

    ABSTRACT Spina bifida is associated with foot deformities, which may lead to foot ulcers, osteomyelitis, and limb amputation. Calcanectomy and Symes amputations have been reported successful in spina bifida. There is lack of evidence for transtibial amputations. This case describes a 27-yr-old woman with L4 level spina bifida who underwent bilateral transtibial amputations. She ambulated with bilateral ankle foot orthoses and canes until age 22. At age 22, she had bilateral foot reconstructive surgeries complicated by nonunion, ulcerations, and osteomyelitis. She was using a wheelchair by age 25. She had elective bilateral transtibial amputations at age 27 for progressive osteomyelitis. Four weeks after amputations, she was fit with bilateral prostheses. On completion of 2 mos of rehabilitation, she ambulated with a cane. This case demonstrates good functional outcomes after transtibial amputations in a young spina bifida patient. Prosthetic fitting should be considered for similar, previously high functioning spina bifida patients with transtibial amputation(s). PMID:26259056

  17. Anaerobic work capacity in elite wheelchair athletes

    NARCIS (Netherlands)

    van der Woude, L H; Bakker, W H; Elkhuizen, J W; Veeger, DirkJan (H. E. J.); Gwinn, T

    1997-01-01

    To study the anaerobic work capacity in wheelchair athletes, 67 elite wheelchair athletes (50 male) were studied in a 30-second sprint test on a computer-controlled wheelchair ergometer during the World Championships and Games for the Disabled in Assen (1990). The experimental set-up (ergometer,

  18. Adaptive sports technology and biomechanics: wheelchairs.

    Science.gov (United States)

    Cooper, Rory A; De Luigi, Arthur Jason

    2014-08-01

    Wheelchair sports are an important tool in the rehabilitation of people with severe chronic disabilities and have been a driving force for innovation in technology and practice. In this paper, we will present an overview of the adaptive technology used in Paralympic sports with a special focus on wheeled technology and the impact of design on performance (defined as achieving the greatest level of athletic ability and minimizing the risk of injury). Many advances in manual wheelchairs trace their origins to wheelchair sports. Features of wheelchairs that were used for racing and basketball 25 or more years ago have become integral to the manual wheelchairs that people now use every day; moreover, the current components used on ultralight wheelchairs also have benefitted from technological advances developed for sports wheelchairs. For example, the wheels now used on chairs for daily mobility incorporate many of the components first developed for sports chairs. Also, advances in manufacturing and the availability of aerospace materials have driven current wheelchair design and manufacture. Basic principles of sports wheelchair design are universal across sports and include fit; minimizing weight while maintaining high stiffness; minimizing rolling resistance; and optimizing the sports-specific design of the chair. However, a well-designed and fitted wheelchair is not sufficient for optimal sports performance: the athlete must be well trained, skilled, and use effective biomechanics because wheelchair athletes face some unique biomechanical challenges. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  19. Relationship between wheelchair durability and wheelchair type and years of test.

    Science.gov (United States)

    Wang, Hongwu; Liu, Hsin-Yi; Pearlman, Jon; Cooper, Rosemarie; Jefferds, Alexandra; Connor, Sam; Cooper, Rory A

    2010-01-01

    To investigate the relationship between the durability of wheelchairs according to American National Standard for Wheechairs/Rehabilitation Engineering and Assistive Technology Society of North America (ANSI/RESNA) Wheelchair Standards and wheelchair type as well as year of test. A retrospective study design with a sample of 246 wheelchairs that were tested in accordance with the ANSI/RESNA standards from 1992 to 2008 including four types of wheelchairs: manual wheelchair (MWC), electrical powered wheelchair (EPW), scooters and pushrim-activated power-assisted wheelchair (PAPAW). Unconditional binary logic regression analysis was chosen to evaluate the relationship between test results and test year as well as wheelchair type. Rehabilitation Engineering Research Center. Wheelchair durability test result (fatigue test: pass or fail) There was no significant correlation between the year when tested and equivalent cycles. A significant relation was found between test results and wheelchair type (Wald score = 10.845, degree of freedom = 3, p = 0.013) with scooters having a significantly higher pass ratio than MWC (OR = 15.629, 95% CI = 2.026-120.579). EPW also had significantly higher pass ratio than MWC (OR = 1.953, 95% CI = 1.049-3.636). No significant difference on pass ratio was found between PAPAW and MWC. No significant improvements in wheelchair test results during the time frame from 1992 to 2008 were discovered. Wheelchair standard tests should be conducted to assure minimum quality of the wheelchairs and for improving the design of wheelchairs. Although the ANSI/RESNA wheelchair durability test procedures have remained consistent, it does not appear that the introduction of new materials, designs and the availability of test data have improved wheelchair fatigue life.

  20. Issues in maintenance and repairs of wheelchairs: A pilot study.

    Science.gov (United States)

    Fitzgerald, Shirley G; Collins, Diane M; Cooper, Rory A; Tolerico, Michelle; Kelleher, Annmarie; Hunt, Peter; Martin, Stephanie; Impink, Bradley; Cooper, Rosemarie

    2005-01-01

    In this pilot study, we assessed wheelchair durability and its effect on user satisfaction. Specifically, we examined the characteristics of the participants' wheelchairs, the types of maintenance and repairs completed, and whether the participants' satisfaction was affected by problems with their wheelchairs. A convenience sample of 130 participants who used wheelchairs as their primary means of mobility was recruited. Participants completed a questionnaire about their wheelchairs, the maintenance and repair history, and their satisfaction levels. Results showed that 26% of the participants had completed a wheelchair repair in the past 6 months, 16% had completed general maintenance, and 27% had completed tire repairs. Neither hours of wheelchair use nor wheelchair age affected repair or maintenance frequency. Participants were generally satisfied with their wheelchairs. Better understanding of wheelchair maintenance and repair issues will guide improvements in wheelchair design and enhance the community participation of individuals who use wheelchairs.

  1. Adjustable wheelchair and method for adjusting said adjustable wheelchair, and wheelchair assembly

    NARCIS (Netherlands)

    Oosterhuis, D.S.

    2013-01-01

    The invention relates to an adjustable wheelchair comprising: -a carriage; -two rear wheels; -at least one front wheel; -at least one footrest; -a sub-frame; -a seat; and -a backrest; wherein the two rear wheels, the at least one front wheel and the at least one footrest are mounted to the carriage,

  2. Control of a stair climbing wheelchair

    Directory of Open Access Journals (Sweden)

    Nor Maniha Abdul Ghani

    2012-08-01

    Full Text Available This paper presents investigations into the control of a stair climbing wheelchair particularly for indoor usage. A virtual wheelchair model is developed using Visual Nastran software and linked with Matlab/Simulink for control purposes. The goals are to have a simple, compact and stable stairs climbing wheelchair in order to complete the ascending and descending tasks. The challenges are to ensure the wheelchair seat always stay at the upright position and to control both the front and rear wheel motors while climbing. PID control is used to provide appropriate torque to both front and rear wheels as well as at to the wheelchair seat during climbing. Results show that the wheelchair movement can be controlled smoothly and the seat maintained at the desired position with the adapted approach.

  3. The Ergonomics of Wheelchair Configuration for Optimal Performance in the Wheelchair Court Sports

    NARCIS (Netherlands)

    Mason, Barry S.; van der Woude, Lucas H. V.; Goosey-Tolfrey, Victoria L.

    2013-01-01

    Optimizing mobility performance in wheelchair court sports (basketball, rugby and tennis) is dependent on a combination of factors associated with the user, the wheelchair and the interfacing between the two. Substantial research has been attributed to the wheelchair athlete yet very little has

  4. Wheelchair service provision education in academia

    Directory of Open Access Journals (Sweden)

    Karen H. Fung

    2017-01-01

    Full Text Available Background: An estimated 70 million people with disabilities need wheelchairs. To address this global crisis, the World Health Organization (WHO proposed an eight-step wheelchair service provision model to ensure service quality regardless of resource setting. The International Society of Wheelchair Professionals (ISWP aims to facilitate the integration of the WHO eight-step model into professional rehabilitation programmes.Objective: To develop an enhanced understanding of the current wheelchair service provision education provided in professional rehabilitation programmes worldwide.Methods: In a cross-sectional design, an online survey was distributed to ISWP contacts of educational institutions. Quantitative responses were analysed through summary statistics and qualitative answers were analysed by content analyses. When relevant, educational institutions were stratified into resource settings.Results: Seventy-two representatives of educational institutions in 21 countries completed the survey. Wheelchair content was taught in 79% of represented institutions, of which 75% of respondents reported using original course material, 10% of respondents used WHO Wheelchair Service Training Packages and 15% of respondents used other available resources. The majority of educational institutions teaching with their own wheelchair-related course material taught ≤ 20 hours. Fourteen of the 15 respondents without wheelchair education, expressed an interest in integrating wheelchair education into their academic curricula.Conclusion: The majority of the educational institutions teach wheelchair education; however, there is great variability in what and how it is taught and evaluated. The results demonstrate the need for more in-depth investigation regarding the integration process of wheelchair education in educational institutions, with the ultimate goal of improving wheelchair service provision worldwide.

  5. Improving Mobility Performance in Wheelchair Basketball.

    Science.gov (United States)

    Veeger, Thom T J; De Witte, Annemarie M H; Berger, Monique A M; Van Der Slikke, Rienk M A; Veeger, Dirkjan H E J; Hoozemans, Marco J M

    2017-10-16

    This study aimed to investigate which characteristics of athlete, wheelchair and athlete-wheelchair interface are the best predictors of wheelchair basketball mobility performance. Sixty experienced wheelchair basketball players performed a wheelchair mobility performance test to assess their mobility performance. To determine which variables were the best predictors of mobility performance, forward stepwise linear regression analyses were performed on a set of 33 characteristics, including ten athlete, nineteen wheelchair and four athlete-wheelchair interface characteristics. Eight of the characteristics turned out to be significant predictors of wheelchair basketball mobility performance. Classification, experience, maximal isometric force, wheel axis height and hand rim diameter - which both interchangeable with each other and wheel diameter - camber angle, and the vertical distance between shoulder and rear wheel axis - which was interchangeable with seat height - were positively associated with mobility performance. The vertical distance between the front seat and the footrest was negatively associated with mobility performance. With this insight, coaches and biomechanical specialists are provided with statistical findings to determine which characteristics they could focus on best to improve mobility performance. Six out of eight predictors are modifiable and can be optimized to improve mobility performance. These adjustments could be carried out both in training (maximal isometric force) and in wheelchair configurations (e.g. camber angle).

  6. Description of a standardized rehabilitation program based on sub-maximal eccentric following a platelet-rich plasma infiltration for jumper’s knee

    Science.gov (United States)

    Kaux, Jean-François; Forthomme, Bénédicte; Namurois, Marie-Hélène; Bauvir, Philippe; Defawe, Nathalie; Delvaux, François; Lehance, Cédric; Crielaard, Jean-Michel; Croisier, Jean-Louis

    2014-01-01

    Summary Introduction. Different series emphasized the necessity of rehabilitation program after infiltration of platelet-rich plasma (PRP) in case of tendinopathy. However, most of them describe only briefly the reeducation protocol and these programs vary. Our aim was to extensively describe a specific standardized rehabilitation program. Methods. After a review of literature of post-PRP infiltration protocols, we had developed a standardized rehabilitation protocol. This protocol was evaluated by 30 subjects with chronic jumper’s knee who. A standardised progressive sub-maximal eccentric program supervised by a physical therapist for 6 weeks was started 1 week post-infiltration. The patient benefited also from electromyostimulation, isometric strengthening and stretching of the quadriceps, cycloergometer and cryotherapy. After the supervised program, the patient had to make an auto-reeducation added to the reathletisation protocol for 6 more weeks which was followed by maintenance exercises up to 1 year. The assessments were made using a VAS, IKDC and VISA-P scores. Results. The VAS, IKDC and VISA-P scores decreased very significantly with time. The compliance to auto-reeducation was good. Conclusions. We proposed a simple and efficient protocol based on sub-maximal eccentric reeducation to add to PRP infiltrations in case of patellar tendinopathy. PMID:24932453

  7. A qualitative examination of wheelchair configuration for optimal mobility performance in wheelchair sports: a pilot study.

    Science.gov (United States)

    Mason, Barry S; Porcellato, Lorna; van der Woude, Lucas H V; Goosey-Tolfrey, Victoria L

    2010-02-01

    To examine wheelchair athletes' perceptions of wheelchair configuration in relation to aspects of mobility performance. Nine elite wheelchair athletes from wheelchair basketball, wheelchair rugby and wheelchair tennis were interviewed using a semi-structured format. Interview transcripts were analysed using an Interpretative Phenomenological Analysis, whereby emergent themes with common connections were identified and clustered into 3 superordinate themes: (i) performance indicators; (ii) principal areas of wheelchair configuration; and (iii) supplementary areas of wheelchair configuration. Participants revealed that stability was the most important contributor towards successful performance. Whilst there was some agreement amongst participants on how manipulating most areas of wheelchair configuration influenced performance, opinions were divided as to whether camber had a positive or negative effect on straight line performance. Experienced athletes seemed to display a good understanding of how modifying wheelchair configurations can affect sports performance, yet the methods offered for identifying optimal settings were extremely subjective. Therefore, future quantitative research into specific areas of configuration is imperative to identify these optimums and to inform athletes about the decisions they make when configuring a new sports wheelchair.

  8. Impact of structured wheelchair services on satisfaction and function of wheelchair users in Zimbabwe

    Directory of Open Access Journals (Sweden)

    Surona Visagie

    2016-02-01

    Full Text Available Background: Providing wheelchairs without comprehensive support services might be detrimental to user satisfaction and function.Objectives: This paper compares wheelchair user satisfaction and function before and after implementation of comprehensive wheelchair services, based on the World Health Organization guidelines on wheelchair service provision in less resourced settings, in Zimbabwe.Method: A pre- and post-test study with a qualitative component was done. Quantitative data were collected with the Quebec User Evaluation of Satisfaction with Assistive Technology for adults and children and the ‘Functioning Every day with a Wheelchair Questionnaire’. Data were collected from 55 consecutively sampled wheelchair users, who received a new wheelchair in the study period. Qualitative data were collected through two audio recorded focus groups and two case studies and are presented through narrative examples.Results: The proportion of adult users who were satisfied significantly increased for all wheelchair and service delivery aspects (p = 0.001 - 0.008, except follow-up (p = 0.128. The same was true for children’s post-test ratings on all variables assessed (p = 0.001 - 0.04, except training in the use of the device (p = 0.052. The biggest improvement in satisfaction figures were for comfort needs (44.3%, indoor mobility (43.2%, outdoor mobility (37.2%, safe and efficient, independent operation (33.5% and transport (31.4%. The qualitative data illustrated user satisfaction with wheelchair features and services.Conclusion: The wheelchair service programme resulted in significant positive changes in user satisfaction with the wheelchair, wheelchair services and function. It is recommended that the Zimbabwean government and partner organisations continue to support and develop wheelchair services along these guidelines.Keywords: Wheelchair; service delivery; function; satisfaction

  9. Peak aerobic work capacity in wheelchair athletes

    NARCIS (Netherlands)

    van der Woude, L.H.V.; Veeger, H.E.J.; Bouten, C.; Gwinn, T.

    2002-01-01

    Objective: To give a descriptive analysis of aerobic capacity among elite wheelchair athletes in association with various personal characteristics and sprint or anaerobic capacity. Design: Sixty-eight wheelchair athletes who participated in the World Games and Championships for the Disabled were

  10. Everyday life for users of electric wheelchairs

    DEFF Research Database (Denmark)

    Rossen, Camilla Blach; Sørensen, Bodil; Jochumsen, Bente Würtz

    2012-01-01

    The aim of this paper is to explore how users of electric wheelchairs experience their everyday life and how their electric wheelchairs influence their daily occupation. Occupation is defined as a personalized dynamic interaction between person, task and environment, and implies the value...

  11. Sub-maximal and maximal Yo-Yo intermittent endurance test level 2: heart rate response, reproducibility and application to elite soccer

    DEFF Research Database (Denmark)

    Bradley, Paul S; Mohr, Magni; Bendiksen, Mads

    2011-01-01

    The aims of this study were to (1) determine the reproducibility of sub-maximal and maximal versions of the Yo-Yo intermittent endurance test level 2 (Yo-Yo IE2 test), (2) assess the relationship between the Yo-Yo IE2 test and match performance and (3) quantify the sensitivity of the Yo-Yo IE2 te......) in Yo-Yo IE2 test performance and heart rate after 6 min were 3.9% (n = 37) and 1.4% (n = 32), respectively. Elite male senior and youth U19 players Yo-Yo IE2 performances were better (P ...

  12. Oxygen uptake-heart rate relationship in élite wheelchair racers.

    Science.gov (United States)

    Tolfrey, K; Goosey-Tolfrey, V L; Campbell, I G

    2001-12-01

    The American College of Sports Medicine (ACSM) recommends that, as a general rule for health purposes, individuals should exercise at 40%-85% of their maximal oxygen uptakes. Moreover, it has been suggested that 55%-90% of the maximal heart rate may be used as an alternative estimate of these percentage maximal oxygen uptake values. The present study examined the relationship between percentage peak heart rate (% HRpeak) and percentage peak oxygen uptake (% VO2peak) during steady-state incremental intensity wheelchair propulsion of 16 élite, male wheelchair racers (WR). Oxygen uptake was determined during each submaximal exercise stage and heart rate (HR) was continuously monitored. The VO2peak was subsequently determined using a separate protocol. Linear regression equations of % HRpeak versus % VO2peak for each participant included % HRpeak values corresponding to 40%, 60%, 80% and 85% VO2peak. The linear regression equation, derived as the group mean of the slope and intercept terms determined for each individual, was: % peak HR = 0.681 x % peak VO2 + 33.2. The group mean of the individual correlation coefficients for the VO2-HR relationship was 0.99. The values of % HRpeak for each of the % VO2peak values below 85% were significantly greater (Pintensity (i.e. % VO2peak) in the WR population. However, in élite level WR, % HRpeak can be recommended as an alternative estimate of % VO2peak at wheelchair propulsion intensities of 85% VO2peak or more.

  13. The effect of Sub-maximal exercise-rehabilitation program on cardio-respiratory endurance indexes and oxygen pulse in patients with spastic cerebral palsy

    Directory of Open Access Journals (Sweden)

    M Izadi

    2006-05-01

    Full Text Available Background: Physical or cardio-respiratory fitness are of the best important physiological variables in children with cerebral palsy (CP, but the researches on exercise response of individuals with CP are limited. Our aim was to determine the effect of sub-maximal rehabilitation program (aerobic exercise on maximal oxygen uptake, oxygen pulse and cardio- respiratory physiological variables of children with moderate to severe spastic cerebral palsy diplegia and compare with able-bodied children. Methods: In a controlled clinical trial study, 15 children with diplegia spastic cerebral palsy, were recruited on a voluntarily basis (experimental group and 18 subjects without neurological impairments selected as control group. In CP group, aerobic exercise program performed on the average of exercise intensity (144 beat per minute of heart rate, 3 times a week for 3 months. The time of each exercise session was 20-25 minutes. Dependent variables were measured in before (pretest and after (post test of rehabilitation program through Mac Master Protocol on Tantories cycle ergometer in CP group and compared with the control group. Results: The oxygen pulse (VO2/HR during ergometery protocol was significantly lower in CP group than normal group (P<0.05. No significant statistical difference in maximal oxygen uptake (VO2 max was found between groups. The rehabilitation program leads to little increase of this variable in CP group. After sub-maximal exercise in pretest and post test, the heart rate of patient group was greater than control group, and aerobic exercise leads to significant decrease in heart rate in CP patients(P<0.05. Conclusion: The patients with spastic cerebral palsy, because of high muscle tone, severe spasticity and involuntarily movements have higher energy cost and lower aerobic fitness than normal people. The rehabilitation exercise program can improve physiological function of muscle and cardio-respiratory endurance in these

  14. Trunk muscle activity during wheelchair ramp ascent and the influence of a geared wheel on the demands of postural control.

    Science.gov (United States)

    Howarth, Samuel J; Polgar, Jan M; Dickerson, Clark R; Callaghan, Jack P

    2010-03-01

    To quantify levels of torso muscular demand during wheelchair ramp ascent and the ability of a geared wheel to influence trunk muscle activity. Repeated-measures design. Each participant completed manual wheelchair ramp ascents for each combination of 4 ramp grades (1:12, 1:10, 1:8, and 1:6) and 3 wheel conditions (in gear, out of gear, and a standard spoked wheel) in a block randomized order by wheel condition. Biomechanics laboratory. Healthy novice wheelchair users (N=13; 6 men) from a university student population. Not applicable. Peak electromyographic activity, expressed as a percentage of maximal voluntary isometric contraction (MVIC) of the abdominals, latissimus dorsi, and erector spinae during ramp ascent. Temporal location of peak electromyographic activity (EMG) within a propulsive cycle and integrated electromyographic activity for a single propulsive cycle. Abdominal peak activity increased 13.9% MVIC while peak posterior trunk muscle activity increased 4.9% MVIC between the shallowest and steepest ramp grades (Pwheel prevented increased peak activity of the rectus abdominis and external oblique (P>.05). Only peak electromyographic timing of the erector spinae was influenced during the push phase by increasing ramp slope. Increased trunk muscular demand as a result of increasing ramp slope is required to enhance stiffness of the spinal column and provide a stable base during manual propulsion. Manual wheelchair users with compromised activity capacity, compromised abdominal muscle strength, or both, may be able to navigate more difficult terrains while using a geared wheelchair wheel because of reduced demands from the abdominal musculature in the geared wheel condition. Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  15. Development of a wheelchair maintenance training programme and questionnaire for clinicians and wheelchair users.

    Science.gov (United States)

    Toro, Maria Luisa; Bird, Emily; Oyster, Michelle; Worobey, Lynn; Lain, Michael; Bucior, Samuel; Cooper, Rory A; Pearlman, Jonathan

    2017-11-01

    Purpose of state: The aims of this study were to develop a Wheelchair Maintenance Training Programme (WMTP) as a tool for clinicians to teach wheelchair users (and caregivers when applicable) in a group setting to perform basic maintenance at home in the USA and to develop a Wheelchair Maintenance Training Questionnaire (WMT-Q) to evaluate wheelchair maintenance knowledge in clinicians, manual and power wheelchair users. The WMTP and WMT-Q were developed through an iterative process. A convenience sample of clinicians (n = 17), manual wheelchair (n ∞ 5), power wheelchair users (n = 4) and caregivers (n = 4) provided feedback on the training programme. A convenience sample of clinicians (n = 38), manual wheelchair (n = 25), and power wheelchair users (n = 30) answered the WMT-Q throughout different phases of development. The subscores of the WMT-Q achieved a reliability that ranged between ICC(3,1) = 0.48 to ICC(3,1) = 0.89. The WMTP and WMT-Q were implemented with 15 clinicians who received in-person training in the USA using the materials developed and showed a significant increase in all except one of the WMT-Q subscores after the WMTP (p users. This training complements the World Health Organization basic wheelchair service curriculum, which only includes training of the clinicians, but does not include detailed information to train wheelchair users and caregivers. This training program offers a time efficient method for providing education to end users in a group setting that may mitigate adverse consequences resulting from wheelchair breakdown. This training program has significant potential for impact among wheelchair users in areas where access to repair services is limited.

  16. Autonomous caregiver following robotic wheelchair

    Science.gov (United States)

    Ratnam, E. Venkata; Sivaramalingam, Sethurajan; Vignesh, A. Sri; Vasanth, Elanthendral; Joans, S. Mary

    2011-12-01

    In the last decade, a variety of robotic/intelligent wheelchairs have been proposed to meet the need in aging society. Their main research topics are autonomous functions such as moving toward some goals while avoiding obstacles, or user-friendly interfaces. Although it is desirable for wheelchair users to go out alone, caregivers often accompany them. Therefore we have to consider not only autonomous functions and user interfaces but also how to reduce caregivers' load and support their activities in a communication aspect. From this point of view, we have proposed a robotic wheelchair moving with a caregiver side by side based on the MATLAB process. In this project we discussing about robotic wheel chair to follow a caregiver by using a microcontroller, Ultrasonic sensor, keypad, Motor drivers to operate robot. Using camera interfaced with the DM6437 (Davinci Code Processor) image is captured. The captured image are then processed by using image processing technique, the processed image are then converted into voltage levels through MAX 232 level converter and given it to the microcontroller unit serially and ultrasonic sensor to detect the obstacle in front of robot. In this robot we have mode selection switch Automatic and Manual control of robot, we use ultrasonic sensor in automatic mode to find obstacle, in Manual mode to use the keypad to operate wheel chair. In the microcontroller unit, c language coding is predefined, according to this coding the robot which connected to it was controlled. Robot which has several motors is activated by using the motor drivers. Motor drivers are nothing but a switch which ON/OFF the motor according to the control given by the microcontroller unit.

  17. Hypersonic propulsion

    Science.gov (United States)

    Cheng, SIN-I.

    1989-01-01

    The paper reviews the whys and hows of the concept of supersonic combustion for hypersonic propulsion. Attention is given to the problem areas, the current research and development efforts, and their implications. The operating boundary of the SCRAMJET is reasonably well defined. The paper also explores some air-breathing alternatives that may go beyond SCRAMJETS.

  18. Solar wheelchair (2); Sora kurumaisu (2)

    Energy Technology Data Exchange (ETDEWEB)

    Okabe, K.; Mikami, H. [Gunma Prefectural College of Health Sciences, Gunma (Japan)

    1998-12-05

    This report is written about the use of sun energy for two kinds of solar wheelchairs. We have made various solar wheelchairs for the aged and sick persons and their examinations on running. If electric wheelchairs equipped with the solar battery 0.7 square meters were by charged the sunlight irradiation for 4 hours, the transit times increased for 1.5 hours. Therefore, we turned out to be able to make the storage battery small, or to decrease the number of times for the charge of the solar battery. (author)

  19. Electrophysiologic and Ultrasonographic Assessment of Carpal Tunnel Syndrome in Wheelchair Basketball Athletes.

    Science.gov (United States)

    Kim, Do Kyun; Kim, Beom Suk; Kim, Min Je; Kim, Ki Hoon; Park, Byung Kyu; Kim, Dong Hwee

    2017-02-01

    To investigate the contributing factors of carpal tunnel syndrome (CTS), electrodiagnostic and ultrasonographic findings of median nerve, and median nerve change after exercise in wheelchair basketball (WCB) players. Fifteen WCB players with manual wheelchairs were enrolled in the study. Medical history of the subjects was taken. Electrodiagnosis and ultrasonography of both median nerves were performed to assess CTS in WCB players. Ultrasonographic median nerves evaluation was conducted after wheelchair propulsion for 20 minutes. Average body mass index (BMI) and period of wheelchair use of CTS subjects were greater than those of normal subjects. Electrodiagnosis revealed CTS in 14 of 30 hands (47%). Cross-sectional area (CSA) of median nerve was greater in CTS subjects than in normal subjects at 0.5 cm and 1 cm proximal to distal wrist crease (DWC), DWC, 1 cm, 2 cm, 3 cm, and 3.5 cm distal to DWC. After exercising, median nerve CSAs at 0.5 cm and 1 cm proximal to DWC, DWC, and 3 cm and 3.5 cm distal to DWC were greater than baseline CSAs in CTS subjects; and median nerve CSAs at 1 cm proximal to DWC and DWC were greater than baseline CSAs in normal subjects. The changes in median nerve CSA after exercise in CTS subjects were greater than in normal subjects at 0.5 cm proximal to DWC and 3 cm and 3.5 cm distal to DWC. BMI and total period of wheelchair use contributed to developing CTS in WCB players. The experimental exercise might be related to the median nerve swelling around the inlet and outlet of carpal tunnel in WCB athletes with CTS.

  20. Propulsion materials

    Energy Technology Data Exchange (ETDEWEB)

    Wall, Edward J. [U.S. Dept. of Energy, Washington, D.C. (United States); Sullivan, Rogelio A. [U.S. Dept. of Energy, Washington, D.C. (United States); Gibbs, Jerry L. [U.S. Dept. of Energy, Washington, D.C. (United States)

    2008-01-01

    The Department of Energy’s (DOE’s) Office of Vehicle Technologies (OVT) is pleased to introduce the FY 2007 Annual Progress Report for the Propulsion Materials Research and Development Program. Together with DOE national laboratories and in partnership with private industry and universities across the United States, the program continues to engage in research and development (R&D) that provides enabling materials technology for fuel-efficient and environmentally friendly commercial and passenger vehicles.

  1. SCAPULOTHORACIC AND GLENOHUMERAL KINEMATICS DURING DAILY TASKS IN USERS OF MANUAL WHEELCHAIRS

    Directory of Open Access Journals (Sweden)

    Kristin D Zhao

    2015-11-01

    Full Text Available Background Rates of shoulder pain in individuals who use manual wheelchairs as their primary means of mobility have been reported to be as high as 70% during activities of daily living. Current prevailing thought is that mechanical impingement of the soft tissues that reside within the subacromial space between the humeral head and coracoacromial arch is a major contributor to the shoulder pain in users of manual wheelchairs. The subacromial space size is directly related to the kinematics at the shoulder joint. Yet to be answered are questions about which common daily tasks are characterized by the most potentially detrimental kinematics. ObjectiveThe purpose of this analysis was to quantify and compare potentially detrimental kinematics in three common tasks performed by individuals with SCI and shoulder pain. These data will add to the body of knowledge, and test common assumptions about relative risk of tasks. DesignA cross-sectional study of 15 manual wheelchair users with shoulder pain.MethodsElectromagnetic surface sensor measures of mean and peak scapulothoracic internal and downward rotation, anterior tilt, and glenohumeral internal rotation were compared across propulsion, weight relief, and scapular plane abduction tasks using one-way repeated measures ANOVA. ResultsStatistical differences were observed between the tasks for all rotations. Mean scapulothoracic anterior tilt was greater in weight relief and propulsion than during scapular plane abduction (24, 23, and 13 degrees of anterior tilt, respectively. Mean GH axial rotation during weight relief was more internally rotated than during propulsion and scapular plane abduction (9, 26, and 51 degrees of external rotation, respectively. LimitationsSurface-based measures of kinematics are subject to skin motion artifact, especially in translation which was not addressed in this study. Conclusions Each task presented with specific variables that might contribute to risk of developing

  2. Pain, fatigue, function and participation among long-term manual wheelchair users partnered with a mobility service dog.

    Science.gov (United States)

    Vincent, Claude; Gagnon, Dany H; Dumont, Frédéric

    2017-11-20

    To assess the effects of a mobility service dog (MSD) on pain, fatigue, wheelchair-related functional tasks, participation and satisfaction among manual wheelchair users over a nine-month period. A longitudinal study with repeated assessment times before and three, six and nine months after intervention was achieved. Intervention consisted in partnering each participant with a MSD. The setting is a well-established provincial service dog training school and participants homes. A convenience sample of 24 long-term manual wheelchair users with a spinal cord injury was involved. Outcome measures were: Wheelchair User's Shoulder Pain Index (WUSPI), Rate of Perceived Exertion (RPE), vitality scale from the SF-36, grip strength, Wheelchair Skills Test (WST), Canadian Occupational Performance Measure (COPM), Reintegration to Normal Living Index (RNLI), Life Space Assessment, Psychosocial Impact of Assistive Devices Scale (PIADS) and Quebec User Evaluation of Satisfaction with assistive Technology (QUEST 2.0). Shoulder and wrist pain as well as fatigue decreased significantly over time with the use of a MSD as evidenced by scores from WUSPI, RPE and SF-36 (feeling less worn out). Manual wheelchair propulsion skills (steep slopes, soft surfaces and thresholds) improved significantly over time as confirmed by the WST. Participation increased significantly over time as revealed by the COPM (for five occupations) and the RNLI (for five items). Satisfaction with the MSD was high over time (QUEST: nine items) and with a high positive psychosocial impact (PIADS: 10 items). MSD represents a valuable mobility assistive technology option for manual wheelchair users. IMPLICATIONS FOR REHABILITATION   For manual wheelchair users partenered with mobility service dog  • Shoulder pain and fatigue significantly decreased and continued to decrease between the third and sixth month and the ninth month.   • Performance with propelling the wheelchair up steep slopes

  3. Speed profiles in wheelchair court sports; comparison of two methods for measuring wheelchair mobility performance.

    Science.gov (United States)

    van der Slikke, R M A; Mason, B S; Berger, M A M; Goosey-Tolfrey, V L

    2017-12-08

    Wheelchair mobility performance is an important aspect in most wheelchair court sports, commonly measured with an indoor tracking system or wheelchair bound inertial sensors. Both methods provide key wheelchair mobility performance outcomes regarding speed. In this study, we compared speed profiles of both methods to gain insight into the level of agreement, for recommendations regarding future performance measurement. Data were obtained from 5 male highly trained wheelchair basketball players during match play. Players were equipped simultaneously with a tag on the footplate for the indoor tracking system (∼8 Hz) and inertial sensors on both wheels and frame (199.8 Hz). Being part of a larger study on 3 vs 3 player game formats, data were collected in several matches with varying field sizes, but activity profiles closely resembled regular match play. Both systems provide similar outcomes regarding distance covered and average speed. Due to differences in sampling frequency and sensor location (reference point) on the wheelchair (for speed calculation), minor differences were revealed at low speeds (wheelchair basketball or wheelchair court sports in general. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. New methods for mobility performance measurement in wheelchair basketball

    NARCIS (Netherlands)

    van der Slikke, R.M.A.; Berger, MAM; Bregman, DJJ; Veeger, H.E.J.

    2016-01-01

    Increased professionalism in wheelchair sports demand a more precise and quantitative measure of individual wheelchair mobility performance, to allow it to be an evaluation measure of wheelchair setting or training optimization. This research describes the application of an inertial sensor based

  5. Physiological evaluation of a newly designed lever mechanism for wheelchairs

    NARCIS (Netherlands)

    van der Woude, L H; Veeger, DirkJan (H. E. J.); de Boer, Y; Rozendal, R H

    1993-01-01

    Lever-propelled wheelchairs have been described as more efficient and less physically demanding than hand-rim-propelled wheelchairs. To evaluate a newly designed lever mechanism (MARC) in both one- and two-arm use, a series of wheelchair exercise tests were performed on a motor-driven treadmill.

  6. 21 CFR 890.3890 - Stair-climbing wheelchair.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Stair-climbing wheelchair. 890.3890 Section 890...) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3890 Stair-climbing wheelchair. (a) Identification. A stair-climbing wheelchair is a device with wheels that is intended for...

  7. Timed motor test for wheelchair users: initial development and application in children with spinal cord injury.

    Science.gov (United States)

    Chafetz, Ross; McDonald, Craig; Mulcahey, M J; Betz, Randal; Anderson, Caroline; Vogel, Lawrence; Gaughan, John P; Martin, Susan; O'Dell, Mary Ann; Flanagan, Ann

    2004-01-01

    The objective of this study was to describe the development and preliminary results of reliability testing of the timed motor test (TMT), a performance-based measure of functional status for children with a spinal cord injury (SCI) who use a manual wheelchair. This study will also provide pilot data using the TMT to examine the impact of thoracolumbosacral orthoses (TLSO) on function in children with a SCI. Cross-sectional observational study. METHODS/PARTICIPANTS: This study enrolled 11 subjects with SCI. The TMT consisted of donning a shirt, donning pants, even transfers, uneven transfers, and propelling a wheelchair 80 feet and up a ramp of 45 feet. Nine subjects completed the TMT with and without a TLSO, and 6 subjects (4 of whom also completed the TMT with and without a TLSO) completed the reliability testing. Except for donning pants, the intertester and intratester reliability of the TMT was fair-to-good with intraclass correlation coefficients (ICCs) of 0.60 or greater. When wearing a TLSO, participants were slower at donning a shirt, donning pants, performing even and uneven transfers, and hallway propulsion (P TLSO for dressing and transfer skills. In general, the TMT for wheelchair users had fair-to-good intertester and intratester reliability. Based on these pilot data, there was an increase in time to complete several functional tasks because of the use of a TLSO as measured by the TMT in children with a SCI.

  8. Effects of inspiratory muscle training on respiratory function and repetitive sprint performance in wheelchair basketball players.

    Science.gov (United States)

    Goosey-Tolfrey, V; Foden, E; Perret, C; Degens, H

    2010-07-01

    There is considerable evidence that respiratory muscle training improves pulmonary function, quality of life and exercise performance in healthy athletic populations. The benefits for wheelchair athletes are less well understood. Therefore, in the present study, influence of inspiratory muscle training (IMT) on respiratory function and repetitive propulsive sprint performance in wheelchair basketball players was examined. Using a placebo-controlled design, 16 wheelchair athletes were divided to an experimental (IMT; n=8) or placebo (sham-IMT; n=8) group based on selective grouping criteria. 30 dynamic breaths were performed by the IMT group twice daily at a resistance equivalent to 50% maximum inspiratory pressure (MIP), and 60 slow breaths were performed by the sham-IMT group once a day at 15% MIP for a period of 6 weeks. In the IMT group, both MIP and maximum expiratory pressure (17% and 23%, respectively; plactate concentration). Reported experiences of using the IMT training device suggested "less breathlessness" and "less tightness in the chest during the training". Although there was no improvement in sprint performance, an improved respiratory muscle function and quality of life were reported by participants in both the IMT and sham-IMT groups.

  9. Shoulder Pain among Rehabilitated Spinal Cord Injured Persons Using Manually Propelled Wheelchairs in the Gaza Strip: A Survey

    Directory of Open Access Journals (Sweden)

    Ziad Al Hawamdah

    2012-08-01

    Full Text Available Shoulder pain among paraplegic persons has negative effects on their lives. The prevalence of shoulder pain among persons with spinal cord injury (SCI varies from 30% to 70% in different studies and may be related to repetitive use of the shoulder during self-care and wheelchair-related activities. Purpose: This study focused on the prevalence of shoulder pain and examined its effects on activities of daily living and social participation, and on functional, work and recreational or athletic activities. It also aimed to detect the degree of satisfaction with shoulder functioning wheelchair users who were paraplegic due to  spinal cord injury, in the Gaza strip.  Methods: Cross sectional study design was used to collect data from 80 persons with paraplegia, post rehabilitation, who were still using manual wheelchairs (MWC for ambulation. After giving informed consent, the selected persons were interviewed directly in their homes, and filled questionnaires which included the demographic data, Wheelchair User’s Shoulder Pain Index (WUSPI and Shoulder Rating Questionnaire (SRQ.Results: The prevalence rate of shoulder pain among paraplegics who use manual wheelchairs was 62%. Pushing a wheelchair for 10 minutes or more, and propulsion up ramps or inclines outdoors were the most common activities that caused and exacerbated shoulder pain. Sixty four percent from among the study sample mentioned that they had no limitation in shoulder-using ability during daily personal and household activities, while the rest experienced different degrees of limitation. Seventy-four percent reported no limitation during recreational or athletic activities, while the rest (26% agreed that pain has variably limited their participation in these activities. Fourteen percent from the sample rated the overall degree of satisfaction with their shoulder functioning as fair, and the rest rated their satisfaction from good to excellent.Conclusion: Shoulder pain, ranging

  10. Electric vehicle propulsion alternatives

    Science.gov (United States)

    Secunde, R. R.; Schuh, R. M.; Beach, R. F.

    1983-01-01

    Propulsion technology development for electric vehicles is summarized. Analytical studies, technology evaluation, and the development of technology for motors, controllers, transmissions, and complete propulsion systems are included.

  11. Effect of choice of recovery patterns on handrim kinetics in manual wheelchair users with paraplegia and tetraplegia

    Science.gov (United States)

    Raina, Shashank; McNitt-Gray, Jill; Mulroy, Sara; Requejo, Philip

    2012-01-01

    Background Impact forces experienced by the upper limb at the beginning of each wheelchair propulsion (WCP) cycle are among the highest forces experienced by wheelchair users. Objective To determine whether the magnitude of hand/forearm velocity prior to impact and effectiveness of rim impact force are dependent on the type of hand trajectory pattern chosen by the user during WCP. Avoiding patterns that inherently cause higher impact force and have lower effectiveness can be another step towards preserving upper limb function in wheelchair users. Methods Kinematic (50 Hz) and kinetic (2500 Hz) data were collected on 34 wheelchair users (16 with paraplegia and 18 with tetraplegia); all participants had motor complete spinal cord injuries ASIA A or B. The four-hand trajectory patterns were analyzed based on velocity prior to contact, peak impact force and the effectiveness of force at impact. Results A high correlation was found between the impact force and the relative velocity of the hand with respect to the wheel (P tetraplegia (P < 0.05). No significant differences in the impact force magnitudes were found between the four observed hand trajectory patterns. Conclusion The overall force effectiveness tended to be associated with the injury level of the user and was found to be independent of the hand trajectory patterns. PMID:22507024

  12. Development, construct validity and test–retest reliability of a field-based wheelchair mobility performance test for wheelchair basketball

    NARCIS (Netherlands)

    de Witte, AMH; Hoozemans, MJM; Berger, MAM; van der Slikke, R.M.A.; van der Woude, LHV; Veeger, H.E.J.

    2018-01-01

    The aim of this study was to develop and describe a wheelchair mobility performance test in wheelchair basketball and to assess its construct validity and reliability. To mimic mobility performance of wheelchair basketball matches in a standardised manner, a test was designed based on observation

  13. Development, construct validity and test–retest reliability of a field-based wheelchair mobility performance test for wheelchair basketball

    NARCIS (Netherlands)

    de Witte, Annemarie M H; Hoozemans, Marco J M; Berger, Monique A M; van der Slikke, Rienk M A; van der Woude, Lucas H V; Veeger, Dirkjan (H E J)

    The aim of this study was to develop and describe a wheelchair mobility performance test in wheelchair basketball and to assess its construct validity and reliability. To mimic mobility performance of wheelchair basketball matches in a standardised manner, a test was designed based on observation of

  14. Development, construct validity and test-retest reliability of a field-based wheelchair mobility performance test for wheelchair basketball

    NARCIS (Netherlands)

    de Witte, Annemarie M. H.; Hoozemans, Marco J. M.; Berger, Monique A. M.; van der Slikke, Rienk M. A.; van der Woude, Lucas H. V.; Veeger, Dirkjan (H. E. J)

    2018-01-01

    The aim of this study was to develop and describe a wheelchair mobility performance test in wheelchair basketball and to assess its construct validity and reliability. To mimic mobility performance of wheelchair basketball matches in a standardised manner, a test was designed based on observation of

  15. Can a 15m-overground wheelchair sprint be used to assess wheelchair-specific anaerobic work capacity?

    NARCIS (Netherlands)

    van der Scheer, Jan W.; de Groot, Sonja; Vegter, Riemer J. K.; Veeger, DirkJan (H. E. J. ); van der Woude, Lucas H. V.

    OBJECTIVE: To evaluate whether outcomes based on stopwatch time and power output (PO) over a 15m-overground wheelchair sprint test can be used to assess wheelchair-specific anaerobic work capacity, by studying their relationship with outcomes on a Wingate-based 30s-wheelchair ergometer sprint

  16. Chemistry and propulsion; Chimie et propulsions

    Energy Technology Data Exchange (ETDEWEB)

    Potier, P. [Maison de la Chimie, 75 - Paris (France); Davenas, A. [societe Nationale des Poudres et des Explosifs - SNPE (France); Berman, M. [Air Force Office of Scientific Research, Arlington, VA (United States)] [and others

    2002-07-01

    During the colloquium on chemistry and propulsion, held in march 2002, ten papers have been presented. The proceedings are brought in this document: ramjet, scram-jet and Pulse Detonation Engine; researches and applications on energetic materials and propulsion; advances in poly-nitrogen chemistry; evolution of space propulsion; environmental and technological stakes of aeronautic propulsion; ramjet engines and pulse detonation engines, automobiles thermal engines for 2015, high temperature fuel cells for the propulsion domain, the hydrogen and the fuel cells in the future transports. (A.L.B.)

  17. MOTION STUDY OF A WHEELCHAIR PROTOTYPE FOR DISABLED PEOPLE

    Directory of Open Access Journals (Sweden)

    Ionut GEONEA

    2015-05-01

    Full Text Available In this paper is presented the design and experimental prototype of a wheelchair for disabled people. Design solution proposed to be implemented uses two reduction gears motors and a mechanical transmission with chains. The motion controller developed uses PWM technology (pulse wave modulation. The wheelchair has the ability of forward – backward motion and steering. The design solution is developed in Solid Works, and it’s implemented to a wheelchair prototype model. Wheelchair design and motion makes him suitable especially for indoor use. It is made a study of the wheelchair kinematics, first using a kinematic simulation in Adams. Are presented the wheelchair motion trajectory and kinematics parameters. The experimental prototype is tested with a motion analysis system based on ultra high speed video recording. The obtained results from simulation and experimentally tests, demonstrate the efficiency of wheelchair proposed solution.

  18. Balance in single-limb stance in healthy subjects – reliability of testing procedure and the effect of short-duration sub-maximal cycling

    Directory of Open Access Journals (Sweden)

    Roberts David

    2003-06-01

    Full Text Available Abstract Background To assess balance in single-limb stance, center of pressure movements can be registered by stabilometry with force platforms. This can be used for evaluation of injuries to the lower extremities. It is important to ensure that the assessment tools we use in the clinical setting and in research have minimal measurement error. Previous studies have shown that the ability to maintain standing balance is decreased by fatiguing exercise. There is, however, a need for further studies regarding possible effects of general exercise on balance in single-limb stance. The aims of this study were: 1 to assess the test-retest reliability of balance variables measured in single-limb stance on a force platform, and 2 to study the effect of exercise on balance in single-limb stance, in healthy subjects. Methods Forty-two individuals were examined for test-retest reliability, and 24 individuals were tested before (pre-exercise and after (post-exercise short-duration, sub-maximal cycling. Amplitude and average speed of center of pressure movements were registered in the frontal and sagittal planes. Mean difference between test and retest with 95% confidence interval, the intraclass correlation coefficient, and the Bland and Altman graphs with limits of agreement, were used as statistical methods for assessing test-retest reliability. The paired t-test was used for comparisons between pre- and post-exercise measurements. Results No difference was found between test and retest. The intraclass correlation coefficients ranged from 0.79 to 0.95 in all stabilometric variables except one. The limits of agreement revealed that small changes in an individual's performance cannot be detected. Higher values were found after cycling in three of the eight stabilometric variables. Conclusions The absence of systematic variation and the high ICC values, indicate that the test is reliable for distinguishing among groups of subjects. However, relatively large

  19. The consequences of shoulder pain intensity on quality of life and community participation in paraplegic wheelchair users

    Directory of Open Access Journals (Sweden)

    Nulle A.

    2012-10-01

    Full Text Available Background/Objective: Shoulder overuse due weight-bearing loads – wheelchair propulsion and transfers – are supposed to cause shoulder pain in active wheelchair users. Consequently, shoulder pain has been found to have a high prevalence in the spinal cord-injured population. Severity of pain levels in individuals with spinal cord injury has been shown to impact quality of life. Aim of this study was to describe the consequences of shoulder pain intensity on quality of life, physical activity, and community activities in spinal cord-injured paraplegic wheelchair users. Materials and Methods: It was a qualitative, analytical one moment study where was involved persons after spinal cord injury below Th1 with lower paraplegia, who used manually operated wheelchairs for mobility at least 50% of the time. Main outcomes measure: SF-36textregistered Health Survey, Physical Activity Scale for Individuals With Physical Disabilities, Community Activities Checklist, Wheelchair User’s Shoulder Pain Index, Functional Independence Measure, Goniometry for shoulder joint. Results and analysis: 40 participants (9 female, 31 male after spinal cord injury (SCI, mean age – 30,8 years, one to twenty years after spinal cord injury. 20 participants had pain in shoulder, 20 participants without pain in shoulder. The intensity of shoulder pain was not related to duration of SCI or the duration of shoulder pain. Shoulder pain intensity scores were inversely related to quality of life. There was a moderate, inverse relationship between shoulder pain intensity and physical activity. There was no relationship, however, between shoulder pain intensity and community activities. The level of community activity was positively related to quality of life. Conclusions: Persons with spinal cord injury who reported lower subjective quality of life and physical activity scores experienced significantly higher levels of shoulder pain. Shoulder pain intensity did not relate to

  20. Enhancing Wheelchair Manoeuvrability for Severe Impairment Users

    Directory of Open Access Journals (Sweden)

    Razali Tomari

    2013-02-01

    Full Text Available A significant number of individuals with severe motor impairments are unable to control their wheelchair using a standard joystick. Even when they can facilitate the control input, navigation in a confined space or crowded environments is still a great challenge. Here we propose a wheelchair framework that enables the user to issue the command via a multi-input hands free interface (HFI, which subsequently assists him/her to overcome difficult circumstances using a multimodal control strategy. Initially the HFI inputs are analysed to infer the desired control mode and the user command. Then environmental information is perceived using a combination of laser and Kinect sensors for determining all possible obstacle locations and outputting a safety map around the wheelchair's vicinity. Eventually, the user's command is validated with the safety map to moderate the final motion, which is collision free and the best for the user's preference. The proposed method can reduce the burden of severe impairment users when controlling wheelchairs by continuously monitoring the surroundings and can make them move easily according to the users' intention.

  1. MANUS: a wheelchair-mounted rehabilitation robot

    NARCIS (Netherlands)

    Driessen, B.J.F.; Evers, H.G.; Woerden, J.A. van

    2001-01-01

    Rehabilitation robots are assistive devices designed for use by people with severe disability in order to gain independence in tasks of daily living. MANUS is a wheelchair-mounted general-purpose manipulator now in use with over 100 people in their homes in the Netherlands, in France and in other

  2. Medical Concerns among Wheelchair Road Racers.

    Science.gov (United States)

    Martinez, Santos F.

    1989-01-01

    Results of a questionnaire administered to 43 wheelchair road racers suggest that their medical problems may lead to complications while training or racing. The study looked at the effects of training, injuries, bladder management, medications, and spasms. Sports medicine professionals are provided with information on handling disabled athletes.…

  3. Training Visual Control in Wheelchair Basketball Shooting

    Science.gov (United States)

    Oudejans, Raoul R. D.; Heubers, Sjoerd; Ruitenbeek, Jean-Rene J. A. C.; Janssen, Thomas W. J.

    2012-01-01

    We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use target information as late as possible.…

  4. Training visual control in wheelchair basketball shooting

    NARCIS (Netherlands)

    Oudejans, R.R.D.; Heubers, S.; Ruitenbeek, J-R.J.A.C.; Janssen, T.W.J.

    2012-01-01

    We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use

  5. Just a Body in a Wheelchair

    Science.gov (United States)

    Rosen, Betty

    2014-01-01

    This article has no direct link with academics, children, students or those who teach: I severed almost all such connections several years ago. It describes the rewards and challenges of leading a reminiscence group of elderly people, all of whom suffer some level of memory loss and/or severe physical disability; most are wheelchair-bound. It…

  6. Wheelchair Neuroprosthesis for Improving Dynamic Trunk Stability.

    Science.gov (United States)

    Patel, Kramay; Milosevic, Matija; Nakazawa, Kimitaka; Popovic, Milos R; Masani, Kei

    2017-07-14

    Trunk instability is a major problem for individuals with thoracic and cervical spinal cord injury. Functional electrical stimulation (FES) neuroprosthesis, a technology that uses small electrical currents to artificially contract muscles, has previously been utilized to improve trunk stability during quasistatic and dynamic sitting. The aim of this study was to develop the first powered wheelchair-based neuroprosthesis and to test its feasibility for improving trunk stability. Eleven male, able-bodied individuals participated in the feasibility study. While participants were seated, the wheelchair was moved in the forward or backward directions with slow and fast accelerations. Two different FES protocols were tested: 1) co-contraction; and 2) directionally-dependent contraction of trunk extensors and flexors. Sham stimulations with intensities below the motor threshold were applied as the control conditions. Inertial motion sensors were used to quantify the maximum angular displacement and velocity of the trunk. Results showed that both directional contractions and co-contraction reduced trunk displacement and velocity, compared to the control conditions. However, directionally-dependent muscle contractions were more effective in improving trunk stability, compared to cocontractions. Overall, feasibility of the wheelchair-based neuroprosthesis was demonstrated. Future research will incorporate feedback from wheelchair movements and test the neuroprosthesis with individuals who sustained spinal cord injury.

  7. Push characteristics in wheelchair court sport sprinting

    NARCIS (Netherlands)

    van der Slikke, R.M.A.; Berger, Monique; Bregman, D.J.J.; Veeger, H.E.J.; van der Helm, FCT; Jansen, AJ

    2016-01-01

    Short sprints are important components of most wheelchair court sports, since being faster than the opponent often determines keeping ball possession or not. Sprinting capacity is best measured during a field test, allowing the athlete to freely choose push strategies adapted to their own

  8. Inverse Dynamics Modeling of Paralympic Wheelchair Curling.

    Science.gov (United States)

    Laschowski, Brock; Mehrabi, Naser; McPhee, John

    2017-08-01

    Paralympic wheelchair curling is an adapted version of Olympic curling played by individuals with spinal cord injuries, cerebral palsy, multiple sclerosis, and lower extremity amputations. To the best of the authors' knowledge, there has been no experimental or computational research published regarding the biomechanics of wheelchair curling. Accordingly, the objective of the present research was to quantify the angular joint kinematics and dynamics of a Paralympic wheelchair curler throughout the delivery. The angular joint kinematics of the upper extremity were experimentally measured using an inertial measurement unit system; the translational kinematics of the curling stone were additionally evaluated with optical motion capture. The experimental kinematics were mathematically optimized to satisfy the kinematic constraints of a subject-specific multibody biomechanical model. The optimized kinematics were subsequently used to compute the resultant joint moments via inverse dynamics analysis. The main biomechanical demands throughout the delivery (ie, in terms of both kinematic and dynamic variables) were about the hip and shoulder joints, followed sequentially by the elbow and wrist. The implications of these findings are discussed in relation to wheelchair curling delivery technique, musculoskeletal modeling, and forward dynamic simulations.

  9. Opportunities for measuring wheelchair kinematics in match settings; reliability of a three inertial sensor configuration

    NARCIS (Netherlands)

    van der Slikke, R.M.A.; Berger, M.A.; Bregman, D.J.J.; Lagerberg, A.H.; Veeger, H.E.J.

    2015-01-01

    Knowledge of wheelchair kinematics during a match is prerequisite for performance improvement in wheelchair basketball. Unfortunately, no measurement system providing key kinematic outcomes proved to be reliable in competition. In this study, the reliability of estimated wheelchair kinematics based

  10. Reliability of the revised wheelchair rugby trunk impairment classification system.

    Science.gov (United States)

    Altmann, V C; Groen, B E; van Limbeek, J; Vanlandewijck, Y C; Keijsers, N L W

    2013-12-01

    Observational, cross-sectional. A new classification system for trunk impairment in wheelchair rugby was introduced in 2010. It consists of 10 tests, arranged in an algorithm, to assign four different trunk scores (0, 0.5, 1.0 or 1.5) to athletes. The purpose of this study was to assess the inter-rater reliability of this classification system. National competition for wheelchair rugby and wheelchair basketball in the Netherlands and Belgium. Three experienced wheelchair rugby classifiers independently assigned trunk scores to wheelchair rugby and wheelchair basketball athletes in two sessions. After each session, test descriptions were adjusted. The inter-rater reliability was evaluated by determining the agreement and Fleiss Kappa. In the first session, all classifiers agreed on the trunk score in 13 out of 16 athletes; the overall Kappa was 0.76 (Pwheelchair rugby showed a adequate inter-rater reliability for the allocation of trunk scores.

  11. Exploring the impact of wheelchair design on user function in a rural South African setting.

    Science.gov (United States)

    Visagie, Surona; Duffield, Svenje; Unger, Mariaan

    2015-01-01

    Wheelchairs provide mobility that can enhance function and community integration. Function in a wheelchair is influenced by wheelchair design. To explore the impact of wheelchair design on user function and the variables that guided wheelchair prescription in the study setting. A mixed-method, descriptive design using convenience sampling was implemented. Quantitative data were collected from 30 wheelchair users using the functioning every day with a Wheelchair Scale and a Wheelchair Specification Checklist. Qualitative data were collected from ten therapists who prescribed wheelchairs to these users, through interviews. The Kruskal-Wallis test was used to identify relationships, and content analysis was undertaken to identify emerging themes in qualitative data. Wheelchairs with urban designs were issued to 25 (83%) participants. Wheelchair size, fit, support and functional features created challenges concerning transport, operating the wheelchair, performing personal tasks, and indoor and outdoor mobility. Users using wheelchairs designed for use in semi-rural environments achieved significantly better scores regarding the appropriateness of the prescribed wheelchair than those using wheelchairs designed for urban use (p = design most often because of a lack of funding, lack of assessment, lack of skills and user choice. Issuing urban type wheelchairs to users living in rural settings might have a negative effect on users' functional outcomes. Comprehensive assessments, further training and research, on long term cost and quality of life implications, regarding provision of a suitable wheelchair versus a cheaper less suitable option is recommended.

  12. Sport orientation model for wheelchair basketball athletes.

    Science.gov (United States)

    Skordilis, E K; Stavrou, N A

    2005-06-01

    This study examined the validity of the Sport Orientation Questionnaire (Competitiveness: 13 items, Win Orientation: 6 items, and Goal Orientation: 6 items) in a sample of 195 wheelchair basketball athletes from the USA. Following evidence for sample-specific validity, the measurement model that underlies the questionnaire was examined. A short-form with 15 items for three factors of Competitiveness (7 items), Win Orientation (5 items) and Goal Orientation (3 items) fit the data (X2/df ratio=2.21, NNFI=.892, CFI=.991, RCFI=.935, SRMR=.058, RMSEA=.071). To evaluate the findings further, we cross-validated the short-form by sex. Structural equation modeling indicated there were similar measurement properties and factor structures for the men and women, indicating similar conceptualization of sport orientations. Meaningful comparisons across sex may be undertaken, since both men and women who are wheelchair basketball athletes perceive the three short-form SOQ factors similarly.

  13. Smart wheelchair: integration of multiple sensors

    Science.gov (United States)

    Gassara, H. E.; Almuhamed, S.; Moukadem, A.; Schacher, L.; Dieterlen, A.; Adolphe, D.

    2017-10-01

    The aim of the present work is to develop a smart wheelchair by integrating multiple sensors for measuring user’s physiological signals and subsequently transmitting and monitoring the treated signals to the user, a designated person or institution. Among other sensors, force, accelerometer, and temperature sensors are successfully integrated within both the backrest and the seat cushions of the wheelchair; while a pulse sensor is integrated within the armrest. The pulse sensor is connected to an amplification circuit board that is, in turn, placed within the armrest. The force and temperature sensors are integrated into a textile cover of the cushions by means of embroidery and sewing techniques. The signal from accelerometer is transmitted through Wi-Fi connection. The electrical connections needed for power supplying of sensors are made by embroidered conductive threads.

  14. Biomechanics and energetics of basketball wheelchairs evolution.

    Science.gov (United States)

    Ardigo', L P; Goosey-Tolfrey, V L; Minetti, A E

    2005-06-01

    The aim of this study was to investigate metabolic demand and mechanical work of different basketball wheelchairs that represented significant stages of its evolution from 1960 to date. Four subjects pushed each model on a basketball court at different speeds (from 0.90 to 2.35 m.s(-1)). During the trials, oxygen consumption was measured. Also, the different forms of mechanical work involved in the exercise were investigated. The oxygen consumption decreased from the oldest model to the next ones, remaining then quite constant. This was also the same with breathing and pushing frequencies. Both the work against air drag and rolling resistance decreased, air drag always played a minor role due to the low speeds investigated. The total mechanical work was highest in the oldest wheelchair and lowest in the newest one. The efficiencies were found similar for all the chairs but the most recent one (less efficient). Already by the 1970's the wheelchair economy had reached an acceptable level, at least partially because of its improved ergonomics. Yet, when focusing on the efficiency, the surprisingly low value with the newest model suggests factors other than the economy (need of better balance, responsiveness, and ground grip) as determinants of the evolution of this device.

  15. Anthropometry and Performance in Wheelchair Basketball.

    Science.gov (United States)

    Granados, Cristina; Yanci, Javier; Badiola, Aduna; Iturricastillo, Aitor; Otero, Montse; Olasagasti, Jurgi; Bidaurrazaga-Letona, Iraia; Gil, Susana M

    2015-07-01

    This study investigated whether anthropometric characteristics, generic and specific sprinting, agility, strength, and endurance capacity could differentiate between First-Division and Third-Division wheelchair basketball (WB) players. A First-Division WB team (n = 8; age = 36.05 ± 8.25 years, sitting body height = 91.38 ± 4.24 cm, body mass = 79.80 ± 12.63 kg) and a Third-Division WB team (n = 11; age = 31.10 ± 6.37 years, sitting body height = 85.56 ± 6.48 cm, body mass = 71.18 ± 17.63 kg) participated in the study. Wheelchair sprint, agility, strength, and endurance tests were performed. The First-Division team was faster (8.7%) in 20 m without the ball, more agile (13-22%), stronger (18-33%), covered more distance (20%) in the endurance test, and presented higher values of rate of perceived exertion for the exercise load (48%) than the Third-Division team. Moreover, the individual 20-m sprint time values correlated inversely with the individual strength/power values (from r = -0.54 to -0.77, p ≤ 0.05, n = 19). Wheelchair basketball coaches should structure strength and conditioning training to improve sprint and agility and evaluate players accordingly, so that they can receive appropriate training stimuli to match the physiological demands of their competitive level.

  16. Rocket propulsion elements

    CERN Document Server

    Sutton, George P

    2011-01-01

    The definitive text on rocket propulsion-now revised to reflect advancements in the field For sixty years, Sutton's Rocket Propulsion Elements has been regarded as the single most authoritative sourcebook on rocket propulsion technology. As with the previous edition, coauthored with Oscar Biblarz, the Eighth Edition of Rocket Propulsion Elements offers a thorough introduction to basic principles of rocket propulsion for guided missiles, space flight, or satellite flight. It describes the physical mechanisms and designs for various types of rockets' and provides an unders

  17. Anaerobic work capacity in elite wheelchair athletes.

    Science.gov (United States)

    van der Woude, L H; Bakker, W H; Elkhuizen, J W; Veeger, H E; Gwinn, T

    1997-01-01

    To study the anaerobic work capacity in wheelchair athletes, 67 elite wheelchair athletes (50 male) were studied in a 30-second sprint test on a computer-controlled wheelchair ergometer during the World Championships and Games for the Disabled in Assen (1990). The experimental set-up (ergometer, protocol) proved to be adequate in terms of power output (P30, P5) velocity and heart rate. Male and female athletes were comparable with respect to personal characteristics (age, body weight, training hours). Track athletes (classified in 4 different functional classes) showed a class-related mean power output (P30: mean power produced during the 30-second sprint period) of 23, 68, 100, and 138 W for the male athletes (n = 38) and 38, 77, and 76 W for females in the upper three classes (n = 10). Sprint power was low for the group of subjects with cerebral palsy (35 W; mixed, n = 6) and relatively high for the amputee group (121 W; mixed, n = 6), female basketball players (81 W; n = 5), and two male field athletes (110 W). Significant differences between male and female athletes were found for P30 and P5 (highest mean power output over any of the six 5-second periods). As was to be expected, mean maximum heart rate in the sprint test varied significantly between the track groups from 112 (high lesion group) to 171 beats/minute(-1) (low lesion group) but not for both genders. The lower P30 in the T1 and T2 groups must be explained not only by the reduced functional muscle mass and impaired coordination but also by phenomena of cardiovascular dysfunction. Based on the performance parameters, the functional classification of the track athletes into four groups seems adequate. P30 was significantly associated with the personal characteristics of gender and hours of training. A significant correlation was found between P30 and sprint performance times for 200 meters (r = -0.79). No correlation was found between either of the forms of power output and the marathon times

  18. Effectiveness and safety of wheelchair skills training program in improving the wheelchair skills capacity: a systematic review.

    Science.gov (United States)

    Tu, Chun-Jing; Liu, Lin; Wang, Wei; Du, He-Ping; Wang, Yu-Ming; Xu, Yan-Bing; Li, Ping

    2017-12-01

    To comprehensively assess the effectiveness and safety of wheelchair skills training program in improving wheelchair skills capacity. PubMed, OVID, EBSCO, ScienceDirect, Web of Science, CINAHL, Cochrane Library, Google Scholar, and China Knowledge Resource Integrated Database were searched up to March 2017. Controlled clinical trials that compared a wheelchair skills training program with a control group that received other interventions and used the wheelchair skills test scores to evaluate wheelchair skills capacity were included. Two authors independently screened articles, extracted data, and assessed the methodological quality using the Cochrane risk-of-bias tool in randomized controlled trial (RCT) and methodological index for non-randomized studies. The data results of wheelchair skills test scores were extracted. Data from 455 individuals in 10 RCTs and from 140 participants in seven non-randomized studies were included for meta-analysis using Stata version 12.0 (Stata Corporation, College Station, TX, USA). In the short term (immediately to one week) post-intervention, relative to a control group, manual wheelchair skills training could increase the total wheelchair skills test scores by 13.26% in RCTs (95% confidence interval (CI), 6.19%-20.34%; P < 0.001) and by 23.44% in non-randomized studies (95% CI, 13.98%-32.90%; P < 0.001). Few adverse events occurred during training; however, compared with a control group, evidence was insufficient to support the effectiveness of powered wheelchair skills training and the long-term (3-12 months) advantage of manual wheelchair skills training ( P = 0.755). The limited evidence suggests that wheelchair skills training program is beneficial in the short term, but its long-term effects remain unclear.

  19. Female Wheelchair Athletes and Changes to Body Image.

    Science.gov (United States)

    Sands, Robert Thomas; Wettenhall, Robyn Sandra

    2000-01-01

    The effects of a psychological intervention program on attitudes of body image of six national female wheelchair basketball players was examined. As a result of the cognitive behavioral intervention program, physical self-perception increased for the wheelchair athletes and for 50 percent of the athletes on multidimensional components of body…

  20. Training Patterns of Wheelchair Basketball Players in Turkey

    Science.gov (United States)

    Tatar, Yasar

    2008-01-01

    The aim of this study was to analyze technical drills, warm-up and cool-down exercises used by wheelchair basketball players of the Turkish league in relation to training sessions. 33 male wheelchair basketball players participated in the study (mean age 26.6[plus or minus]5,95 years). All players reported that they used warm-up exercises before…

  1. Locally manufactured wheelchairs in Tanzania – are users satisfied ...

    African Journals Online (AJOL)

    Background: The government of Tanzania created opportunity for the production of wheelchairs that would be appropriate to the local needs and environment. Objectives: The study assessed the extent to which the wheelchairs met the activity and participation needs of the users, as well as the users' level of satisfaction ...

  2. Capturing hand tremors with a fuzzy logic wheelchair joystick controller

    NARCIS (Netherlands)

    van der Zwaag, B.J.; Corbett, Dan

    We have designed and built a fuzzy logic wheelchair controller which minimizes the effect of Multiple Sclerosis and tremors. The aim of our project has been to give people with Multiple Sclerosis better control of an electric wheelchair by removing tremors from the joystick signal. The system

  3. Wheelchair-mounted accelerometers for measurement of physical activity.

    Science.gov (United States)

    Gendle, Shawn C; Richardson, Mark; Leeper, James; Hardin, L Brent; Green, J Matt; Bishop, Phillip A

    2012-03-01

    To evaluate the validity of a wheelchair frame-mounted accelerometer for the assessment of physical activity of wheelchair users. Twelve collegiate wheelchair basketball players participated in this study. The study was conducted in a modern indoor gymnasium at a university in the USA. A randomized, crossover experimental design was used to investigate accelerometer output, participant heart rate, and distance travelled. Participants performed two trials of wheeling at a combination of two different effort levels (light and moderate: Prescribed using perceived exertion) and two different modes (continuous and stop-go). Accelerometer vector magnitude activity counts (VM), heart rate (HR), and distance travelled were significantly different between light and moderate effort (p wheelchair frame-mounted accelerometer differentiated between perceptually-prescribed low and moderate effort levels and may prove to be a valid instrument in the detection of a wheelchair users' physical activity. [Box: see text].

  4. Wheelchair ergonomic hand drive mechanism use improves wrist mechanics associated with carpal tunnel syndrome.

    Science.gov (United States)

    Zukowski, Lisa A; Roper, Jaimie A; Shechtman, Orit; Otzel, Dana M; Hovis, Patty W; Tillman, Mark D

    2014-01-01

    Among conventional manual wheelchair (CMW) users, 49% to 63% experience carpal tunnel syndrome (CTS) that is likely induced by large forces transmitted through the wrist and extreme wrist orientations. The ergonomic hand drive mechanism (EHDM) tested in this study has been shown to utilize a more neutral wrist orientation. This study evaluates the use of an EHDM in terms of wrist orientations that may predispose individuals to CTS. Eleven adult full-time CMW users with spinal cord injury participated. Motion data were captured as participants propelled across a flat surface, completing five trials in a CMW and five trials in the same CMW fitted with the EHDM. Average angular wrist orientations were compared between the two propulsion styles. Use of the EHDM resulted in reduced wrist extension and ulnar deviation. The shift to more neutral wrist orientations observed with EHDM use may reduce median nerve compression.

  5. Wheelchair ergonomic hand drive mechanism use improves wrist mechanics associated with carpal tunnel syndrome

    Science.gov (United States)

    Zukowski, Lisa A.; Roper, Jaimie A.; Shechtman, Orit; Otzel, Dana M.; Hovis, Patty W.; Tillman, Mark D.

    2015-01-01

    Among conventional manual wheelchair (CMW) users, 49% to 63% experience carpal tunnel syndrome (CTS) that is likely induced by large forces transmitted through the wrist and extreme wrist orientations. The ergonomic hand drive mechanism (EHDM) tested in this study has been shown to utilize a more neutral wrist orientation. This study evaluates the use of an EHDM in terms of wrist orientations that may predispose individuals to CTS. Eleven adult full-time CMW users with spinal cord injury participated. Motion data were captured as participants propelled across a flat surface, completing five trials in a CMW and five trials in the same CMW fitted with the EHDM. Average angular wrist orientations were compared between the two propulsion styles. Use of the EHDM resulted in reduced wrist extension and ulnar deviation. The shift to more neutral wrist orientations observed with EHDM use may reduce median nerve compression. PMID:25856042

  6. Rasch Analyses of the Wheelchair Use Confidence Scale for Power Wheelchair Users.

    Science.gov (United States)

    Sakakibara, Brodie M; Miller, William C; Rushton, Paula W; Polgar, Jan Miller

    2018-01-01

    To examine the dimensionality of the Wheelchair Use Confidence Scale for power wheelchair users (WheelCon-P), to identify items that do not fit the Rasch rating scale model as well as redundant items for elimination, and to determine the SEMs and reliability estimates for the entire range of measurements. Secondary analysis of cross-sectional data. Community. Volunteer participants (N=189) using wheelchairs (mean age of the sample, 56.7±13.0y; mean years of wheelchair use experience, 20.4±16.4). Not applicable. 59-Item WheelCon-P. Principal component analyses confirmed the presence of 2 self-efficacy dimensions: mobility and social situation. Eleven mobility items and 5 social situation items fit the Rasch rating scale model. Three items misfit the model using all 16 items (ie, WheelCon-P short form). In each of the mobility, social situation, and WheelCon-P short form range of measurements, the 2 lowest and 2 highest measures had internal consistency reliability estimates below .70; all other measures had reliability estimates above .70. The WheelCon-P is composed of 2 self-efficacy dimensions related to mobility and social situations. The scores from the WheelCon-P short form and the 11-item mobility and 5-item social situation dimensions using a 0 to 10 response scale have good reliability. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  7. Development, construct validity and test-retest reliability of a field-based wheelchair mobility performance test for wheelchair basketball.

    Science.gov (United States)

    de Witte, Annemarie M H; Hoozemans, Marco J M; Berger, Monique A M; van der Slikke, Rienk M A; van der Woude, Lucas H V; Veeger, Dirkjan H E J

    2018-01-01

    The aim of this study was to develop and describe a wheelchair mobility performance test in wheelchair basketball and to assess its construct validity and reliability. To mimic mobility performance of wheelchair basketball matches in a standardised manner, a test was designed based on observation of wheelchair basketball matches and expert judgement. Forty-six players performed the test to determine its validity and 23 players performed the test twice for reliability. Independent-samples t-tests were used to assess whether the times needed to complete the test were different for classifications, playing standards and sex. Intraclass correlation coefficients (ICC) were calculated to quantify reliability of performance times. Males performed better than females (P wheelchair basketball athletes. Furthermore, the described methodology of development is recommended for use in other sports to develop sport-specific tests.

  8. Capturing and analyzing wheelchair maneuvering patterns with mobile cloud computing.

    Science.gov (United States)

    Fu, Jicheng; Hao, Wei; White, Travis; Yan, Yuqing; Jones, Maria; Jan, Yih-Kuen

    2013-01-01

    Power wheelchairs have been widely used to provide independent mobility to people with disabilities. Despite great advancements in power wheelchair technology, research shows that wheelchair related accidents occur frequently. To ensure safe maneuverability, capturing wheelchair maneuvering patterns is fundamental to enable other research, such as safe robotic assistance for wheelchair users. In this study, we propose to record, store, and analyze wheelchair maneuvering data by means of mobile cloud computing. Specifically, the accelerometer and gyroscope sensors in smart phones are used to record wheelchair maneuvering data in real-time. Then, the recorded data are periodically transmitted to the cloud for storage and analysis. The analyzed results are then made available to various types of users, such as mobile phone users, traditional desktop users, etc. The combination of mobile computing and cloud computing leverages the advantages of both techniques and extends the smart phone's capabilities of computing and data storage via the Internet. We performed a case study to implement the mobile cloud computing framework using Android smart phones and Google App Engine, a popular cloud computing platform. Experimental results demonstrated the feasibility of the proposed mobile cloud computing framework.

  9. A conceptual framework to assess effectiveness in wheelchair provision.

    Science.gov (United States)

    Kamaraj, Deepan C; Bray, Nathan; Rispin, Karen; Kankipati, Padmaja; Pearlman, Jonathan; Borg, Johan

    2017-01-01

    Currently, inadequate wheelchair provision has forced many people with disabilities to be trapped in a cycle of poverty and deprivation, limiting their ability to access education, work and social facilities. This issue is in part because of the lack of collaboration among various stakeholders who need to work together to design, manufacture and deliver such assistive mobility devices. This in turn has led to inadequate evidence about intervention effectiveness, disability prevalence and subsequent costeffectiveness that would help facilitate appropriate provision and support for people with disabilities. In this paper, we describe a novel conceptual framework that can be tested across the globe to study and evaluate the effectiveness of wheelchair provision. The Comparative Effectiveness Research Subcommittee (CER-SC), consisting of the authors of this article, housed within the Evidence-Based Practice Working Group (EBP-WG) of the International Society of Wheelchair Professionals (ISWP), conducted a scoping review of scientific literature and standard practices used during wheelchair service provision. The literature review was followed by a series of discussion groups. The three iterations of the conceptual framework are described in this manuscript. We believe that adoption of this conceptual framework could have broad applications in wheelchair provision globally to develop evidence-based practices. Such a perspective will help in the comparison of different strategies employed in wheelchair provision and further improve clinical guidelines. Further work is being conducted to test the efficacy of this conceptual framework to evaluate effectiveness of wheelchair service provision in various settings across the globe.

  10. Modeling and Simulation of Two Wheelchair Accessories for Pushing Doors.

    Science.gov (United States)

    Abdullah, Soran Jalal; Shaikh Mohammed, Javeed

    2017-03-27

    Independent mobility is vital to individuals of all ages, and wheelchairs have proven to be great personal mobility devices. The tasks of opening and navigating through a door are trivial for healthy people, while the same tasks could be difficult for some wheelchair users. A wide range of intelligent wheelchair controllers and systems, robotic arms, or manipulator attachments integrated with wheelchairs have been developed for various applications, including manipulating door knobs. Unfortunately, the intelligent wheelchairs and robotic attachments are not widely available as commercial products. Therefore, the current manuscript presents the modeling and simulation of a novel but simple technology in the form of a passive wheelchair accessory (straight, arm-like with a single wheel, and arc-shaped with multiple wheels) for pushing doors open from a wheelchair. From the simulations using different wheel shapes and sizes, it was found that the arc-shaped accessory could push open the doors faster and with almost half the required force as compared to the arm-like accessory. Also, smaller spherical wheels were found to be best in terms of reaction forces on the wheels. Prototypes based on the arc-shaped accessory design will be manufactured and evaluated for pushing doors open and dodging or gliding other obstacles.

  11. Reliability and minimal detectable change of a new treadmill-based progressive workload incremental test to measure cardiorespiratory fitness in manual wheelchair users.

    Science.gov (United States)

    Gauthier, Cindy; Arel, Jasmine; Brosseau, Rachel; Hicks, Audrey L; Gagnon, Dany H

    2017-11-01

    Cardiorespiratory fitness training is commonly provided to manual wheelchair users (MWUs) in rehabilitation and physical activity programs, emphasizing the need for a reliable task-specific incremental wheelchair propulsion test. Quantifying test-retest reliability and minimal detectable change (MDC) of key cardiorespiratory fitness measures following performance of a newly developed continuous treadmill-based wheelchair propulsion test (WPTTreadmill). Twenty-five MWUs completed the WPTTreadmill on two separate occasions within one week. During these tests, participants continuously propelled their wheelchair on a motorized treadmill while the exercise intensity was gradually increased every minute until exhaustion by changing the slope and/or speed according to a standardized protocol. Peak oxygen consumption (VO2peak), carbon dioxide production (VCO2peak), respiratory exchange ratio (RERpeak), minute ventilation (VEpeak) and heart rate (HRpeak) were computed. Time to exhaustion (TTE) and number of increments completed were also measured. Intra-class correlation coefficients (ICC) were calculated to determine test-retest reliability. Standard error of measurement (SEM) and MDC90% values were calculated. Excellent test-retest reliability was reached for almost all outcome measures (ICC=0.91-0.76), except for RERpeak (ICC=0.58), which reached good reliability. TTE (ICC=0.89) and number of increments (ICC=0.91) also reached excellent test-retest reliability. For the main outcome measures (VO2peak and TTE), absolute SEM was 2.27 mL/kg/min and 0.76 minutes, respectively and absolute MDC90% was 5.30 mL/kg/min and 1.77 minutes, respectively. The WPTTreadmill is a reliable test to assess cardiorespiratory fitness among MWUs. TTE and number of increments could be used as reliable outcome measures when VO2 measurement is not possible.

  12. Cold Gas Micro Propulsion

    NARCIS (Netherlands)

    Louwerse, M.C.

    2009-01-01

    This thesis describes the development of a micro propulsion system. The trend of miniaturization of satellites requires small sized propulsion systems. For particular missions it is important to maintain an accurate distance between multiple satellites. Satellites drift apart due to differences in

  13. Electric propulsion cost estimation

    Science.gov (United States)

    Palaszewski, B. A.

    1985-01-01

    A parametric cost model for mercury ion propulsion modules is presented. A detailed work breakdown structure is included. Cost estimating relationships were developed for the individual subsystems and the nonhardware items (systems engineering, software, etc.). Solar array and power processor unit (PPU) costs are the significant cost drivers. Simplification of both of these subsystems through applications of advanced technology (lightweight solar arrays and high-efficiency, self-radiating PPUs) can reduce costs. Comparison of the performance and cost of several chemical propulsion systems with the Hg ion module are also presented. For outer-planet missions, advanced solar electric propulsion (ASEP) trip times and O2/H2 propulsion trip times are comparable. A three-year trip time savings over the baselined NTO/MMH propulsion system is possible with ASEP.

  14. Wheelchair skills performance between discharge and one year after inpatient rehabilitation in hand-rim wheelchair users with spinal cord injury

    NARCIS (Netherlands)

    Fliess-Douer, Osnat; Vanlandewijck, Yves C.; Post, Marcel W. M.; Van Der Woude, Lucas H. V.; De Groot, Sonja

    Objective: To study possible changes in wheelchair skills in participants with spinal cord injury between discharge and 1 year after rehabilitation, and to determine whether changes in wheelchair skills performance are related to lesion and personal characteristics, self-efficacy, and wheelchair

  15. Comparison between performances of three types of manual wheelchairs often distributed in low-resource settings.

    Science.gov (United States)

    Rispin, Karen; Wee, Joy

    2015-07-01

    This study was conducted to compare the performance of three types of chairs in a low-resource setting. The larger goal was to provide information which will enable more effective use of limited funds by wheelchair manufacturers and suppliers in low-resource settings. The Motivation Rough Terrain and Whirlwind Rough Rider were compared in six skills tests which participants completed in one wheelchair type and then a day later in the other. A hospital-style folding transport wheelchair was also included in one test. For all skills, participants rated the ease or difficulty on a visual analogue scale. For all tracks, distance traveled and the physiological cost index were recorded. Data were analyzed using repeated measures analysis of variance. The Motivation wheelchair outperformed Whirlwind wheelchair on rough and smooth tracks, and in some metrics on the tight spaces track. Motivation and Whirlwind wheelchairs significantly outperformed the hospital transport wheelchair in all metrics on the rough track skills test. This comparative study provides data that are valuable for manufacturers and for those who provide wheelchairs to users. The comparison with the hospital-style transport chair confirms the cost to users of inappropriate wheelchair provision. Implications for Rehabilitation For those with compromised lower limb function, wheelchairs are essential to enable full participation and improved quality of life. Therefore, provision of wheelchairs which effectively enable mobility in the cultures and environments in which people with disabilities live is crucial. This includes low-resource settings where the need for appropriate seating is especially urgent. A repeated measures study to measure wheelchair performances in everyday skills in the setting where wheelchairs are used gives information on the quality of mobility provided by those wheelchairs. This study highlights differences in the performance of three types of wheelchairs often distributed in low

  16. A comparison of the physiological demands of wheelchair basketball and wheelchair tennis.

    Science.gov (United States)

    Croft, Louise; Dybrus, Suzanne; Lenton, John; Goosey-Tolfrey, Victoria

    2010-09-01

    To examine the physiological profiles of wheelchair basketball and tennis and specifically to: (a) identify if there are differences in the physiological profiles of wheelchair basketball and tennis players of a similar playing standard, (b) to determine whether the competitive physiological demands of these sports differed (c) and to explore the relationship between the blood lactate [Bla-] response to exercise and to identify the sport specific heart rate (HR) training zones. Six elite athletes (4 male, 2 female) from each sport performed a submaximal and VO2peak test in their sport specific wheelchair. Heart rate, VO2, and [Bla-] were measured. Heart rate was monitored during international competitions and VO2 was calculated from this using linear regression equations. Individual HR training zones were identified from the [Bla-] profile and time spent within these zones was calculated for each match. Despite no differences in the laboratory assessment of HRpeak, the VO2peak was higher for the basketball players when compared with the tennis players (2.98 ± 0.91 vs 2.06 ± 0.71; P = .08). Average match HR (163 ± 11 vs 146 ± 16 beats x min(-1); P = .06) and average VO2 (2.26 ± 0.06 vs 1.36 ± 0.42 L x min(-1); P = .02) were higher during actual playing time of basketball when compared with whole tennis play. Consequently, differences in the time spent in the different training zones within and between the two sports existed (P Wheelchair basketball requires predominately high-intensity training, whereas tennis training requires training across the exercise intensity spectrum.

  17. Moving a patient from bed to a wheelchair

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000428.htm Moving a patient from bed to a wheelchair To use the sharing features on this ... move the footrests out of the way. Getting a Patient Ready to Transfer Before transferring into the ...

  18. Re-embodiment: incorporation through embodied learning of wheelchair skills.

    Science.gov (United States)

    Standal, Øyvind F

    2011-05-01

    In this article, the notion of re-embodiment is developed to include the ways that rearrangement and renewals of body schema take place in rehabilitation. More specifically, the embodied learning process of acquiring wheelchair skills serves as a starting point for fleshing out a phenomenological understanding of incorporation of assistive devices. By drawing on the work of Merleau-Ponty, the reciprocal relation between acquisition habits and incorporation of instruments is explored in relation to the learning of wheelchair skills. On the basis of this, it is argued that through learning to manoeuvre the wheelchair, a reversible relation between is established between the moving body-subject and the wheelchair. In this sense, re-embodiment involves a gestalt switch from body image to body schema.

  19. Tongue-Driven Wheelchair Out-Maneuvers the Competition

    Science.gov (United States)

    ... to other assistive devices used by individuals with tetraplegia. In a small clinical trial, the researchers showed for the first time that individuals with tetraplegia can maneuver a wheelchair three times faster using ...

  20. Mobile Augmented Reality enhances indoor navigation for wheelchair users

    National Research Council Canada - National Science Library

    Oliveira, Luciene Chagas de; Soares, Alcimar Barbosa; Cardoso, Alexandre; Andrade, Adriano de Oliveira; Lamounier Júnior, Edgard Afonso

    2016-01-01

    ...). The main objective of this work is to propose an architecture based on Mobile Augmented Reality to support the development of indoor navigation systems dedicated to wheelchair users, that is also...

  1. Older people's use of powered wheelchairs for activity and participation

    DEFF Research Database (Denmark)

    Brandt, Ase; Iwarsson, Susanne; Ståhle, Agneta

    2004-01-01

    OBJECTIVE: The aims of this study were to investigate outcomes of older people's use of powered wheelchairs and risk factors for negative outcomes. DESIGN: The study was a cross-sectional interview-study including 111 powered wheelchair users over 65 years of age. RESULTS: All participants used...... not use the wheelchair for visits, and supplementary travel modes are called for. Users who could not walk at all or who could not transfer without assistance were more likely not to be able to carry out prioritized activities. Furthermore, other risk factors for negative outcomes and need for further...... research were identified. CONCLUSION: The use of powered wheelchairs is a relevant societal intervention in relation to older people with limited walking ability in order to make activity and participation possible. It is likely that a larger proportion of older people could benefit from this intervention...

  2. WISDOM: wheelchair inertial sensors for displacement and orientation monitoring

    Science.gov (United States)

    Pansiot, J.; Zhang, Z.; Lo, B.; Yang, G. Z.

    2011-10-01

    Improved wheelchair design in recent years has significantly increased the mobility of people with disabilities, which has also enhanced the competitive advantage of wheelchair sports. For the latter, detailed assessment of biomechanical factors influencing individual performance and team tactics requires real-time wireless sensing and data modelling. In this paper, we propose the use of a miniaturized wireless wheel-mounted inertial sensor for wheelchair motion monitoring and tracking in an indoor sport environment. Based on a combined use of 3D microelectromechanical system (MEMS) gyroscopes and 2D MEMS accelerometers, the proposed system provides real-time velocity, heading, ground distance covered and motion trajectory of the wheelchair across the sports court. The proposed system offers a number of advantages compared to existing platforms in terms of size, weight and ease of installation. Beyond sport applications, it also has important applications for training and rehabilitation for people with disabilities.

  3. Participatory design and validation of mobility enhancement robotic wheelchair

    National Research Council Canada - National Science Library

    Daveler, Brandon; Salatin, Benjamin; Grindle, Garrett G; Candiotti, Jorge; Wang, Hongwu; Cooper, Rory A

    2015-01-01

    ...) users regarding the conditions they encounter when driving in both indoor and outdoor environments that may affect their safety and result in them becoming immobilized, tipping over, or falling out of their wheelchair...

  4. Distributed Propulsion Vehicles

    Science.gov (United States)

    Kim, Hyun Dae

    2010-01-01

    Since the introduction of large jet-powered transport aircraft, the majority of these vehicles have been designed by placing thrust-generating engines either under the wings or on the fuselage to minimize aerodynamic interactions on the vehicle operation. However, advances in computational and experimental tools along with new technologies in materials, structures, and aircraft controls, etc. are enabling a high degree of integration of the airframe and propulsion system in aircraft design. The National Aeronautics and Space Administration (NASA) has been investigating a number of revolutionary distributed propulsion vehicle concepts to increase aircraft performance. The concept of distributed propulsion is to fully integrate a propulsion system within an airframe such that the aircraft takes full synergistic benefits of coupling of airframe aerodynamics and the propulsion thrust stream by distributing thrust using many propulsors on the airframe. Some of the concepts are based on the use of distributed jet flaps, distributed small multiple engines, gas-driven multi-fans, mechanically driven multifans, cross-flow fans, and electric fans driven by turboelectric generators. This paper describes some early concepts of the distributed propulsion vehicles and the current turboelectric distributed propulsion (TeDP) vehicle concepts being studied under the NASA s Subsonic Fixed Wing (SFW) Project to drastically reduce aircraft-related fuel burn, emissions, and noise by the year 2030 to 2035.

  5. Advanced Propulsion Research Interest in Materials for Propulsion

    Science.gov (United States)

    Cole, John

    2003-01-01

    This viewgraph presentation provides an overview of material science and technology in the area of propulsion energetics. The authors note that conventional propulsion systems are near peak performance and further refinements in manufacturing, engineering design and materials will only provide incremental increases in performance. Energetic propulsion technologies could potential solve the problems of energy storage density and energy-to-thrust conversion efficiency. Topics considered include: the limits of thermal propulsion systems, the need for energetic propulsion research, emerging energetic propulsion technologies, materials research needed for advanced propulsion, and potential research opportunities.

  6. Alternative propulsion for automobiles

    CERN Document Server

    Stan, Cornel

    2017-01-01

    The book presents – based on the most recent research and development results worldwide - the perspectives of new propulsion concepts such as electric cars with batteries and fuel cells, and furthermore plug in hybrids with conventional and alternative fuels. The propulsion concepts are evaluated based on specific power, torque characteristic, acceleration behaviour, specific fuel consumption and pollutant emissions. The alternative fuels are discussed in terms of availability, production, technical complexity of the storage on board, costs, safety and infrastructure. The book presents summarized data about vehicles with electric and hybrid propulsion. The propulsion of future cars will be marked by diversity – from compact electric city cars and range extender vehicles for suburban and rural areas up to hybrid or plug in SUV´s, Pick up´s and luxury class automobiles.

  7. Hypersonic Missile Propulsion System

    National Research Council Canada - National Science Library

    Kazmar, Richard

    1998-01-01

    .... A supersonic combustion ramjet (scramjet) database was developed using hydrogen fueled propulsion systems for space access vehicles and serves as a point of departure for the current development of hydrocarbon scramjets...

  8. Quantification of activity during wheelchair basketball and rugby at the National Veterans Wheelchair Games: A pilot study.

    Science.gov (United States)

    Sporner, Michelle L; Grindle, Garrett G; Kelleher, Annmarie; Teodorski, Emily E; Cooper, Rosemarie; Cooper, Rory A

    2009-09-01

    To date, no published data exists on distances and speeds traveled by rugby or basketball players during game play. The purpose of this study was to provide quantitative information of selected characteristics of wheelchair basketball and rugby game play. A miniaturized data logger was used to collect the distance traveled, average velocity, activity time, and number of starts and stops during basketball and rugby games. Participants were recruited prior to wheelchair basketball and rugby tournaments during the 2007 and 2008 National Veterans Wheelchair Games. Inclusion criteria were age 18 years or older and been participating in wheelchair basketball or rugby. The wheelchair rugby athletes on average traveled 2364.78 +/- 956.35 meters at 1.33 +/- 0.25 m/sec with 242.61 +/- 80.31 stops and starts in 29.98 +/- 11.79 min of play per game. The wheelchair basketball athletes on average traveled 2679.52 +/- 1103.66 m at 1.48 +/- 0.13 m/sec with 239.78 +/- 60.61 stops and starts in 30.28 +/- 9.59 min of play per game. Previous research has not reported basketball or rugby game play variables such as these, making this data set unique. The information could be used by players and coaches to create training protocols to better prepare for game conditions.

  9. Electric Vehicle Propulsion System

    OpenAIRE

    Keshri, Ritesh Kumar

    2014-01-01

    Electric vehicles are being considered as one of the pillar of eco-friendly solutions to overcome the problem of global pollution and radiations due to greenhouse gases. Present thesis work reports the improvement in overall performance of the propulsion system of an electric vehicle by improving autonomy and torque-speed characteristic. Electric vehicle propulsion system consists of supply and traction system, and are coordinated by the monitoring & control system. Case of light electric veh...

  10. Fuel Effective Photonic Propulsion

    Science.gov (United States)

    Rajalakshmi, N.; Srivarshini, S.

    2017-09-01

    With the entry of miniaturization in electronics and ultra-small light-weight materials, energy efficient propulsion techniques for space travel can soon be possible. We need to go for such high speeds so that the generation’s time long interstellar missions can be done in incredibly short time. Also renewable energy like sunlight, nuclear energy can be used for propulsion instead of fuel. These propulsion techniques are being worked on currently. The recently proposed photon propulsion concepts are reviewed, that utilize momentum of photons generated by sunlight or onboard photon generators, such as blackbody radiation or lasers, powered by nuclear or solar power. With the understanding of nuclear photonic propulsion, in this paper, a rough estimate of nuclear fuel required to achieve the escape velocity of Earth is done. An overview of the IKAROS space mission for interplanetary travel by JAXA, that was successful in demonstrating that photonic propulsion works and also generated additional solar power on board, is provided; which can be used as a case study. An extension of this idea for interstellar travel, termed as ‘Star Shot’, aims to send a nanocraft to an exoplanet in the nearest star system, which could be potentially habitable. A brief overview of the idea is presented.

  11. Defining health-related quality of life for young wheelchair users: A qualitative health economics study

    National Research Council Canada - National Science Library

    Nathan Bray; Jane Noyes; Nigel Harris; Rhiannon Tudor Edwards

    2017-01-01

    ...; an important concept in health economics. The aim of this research was to understand how young wheelchair users and their parents define health-related quality of life in relation to mobility impairment and wheelchair use...

  12. Occupant restraint preferences of individuals traveling in motor vehicles while seated in their wheelchairs.

    Science.gov (United States)

    van Roosmalen, Linda; Lutgendorf, Marlies; Manary, Miriam A

    2008-01-01

    A survey among 127 wheelchair users was conducted to characterize wheelchair occupant restraint usage patterns, restraint deficiencies, user characteristics, and essential wheelchair occupant restraint design parameters for when individuals travel in motor vehicles while seated in their wheelchairs. Survey respondents value independent travel and seem generally interested in the use of an occupant restraint system that is attached to the wheelchair frame and that can be used independently by the wheelchair user without caregiver or vehicle driver assistance. Results of the survey further indicate that despite the relatively high percentage of respondents who are attempting to travel safely (78.8%), almost half of these wheelchair users have experienced injury or compromised wheelchair balance while traveling in motor vehicles.

  13. From big data to rich data : The key features of athlete wheelchair mobility performance

    NARCIS (Netherlands)

    van der Slikke, R.M.A.; Berger, MAM; Bregman, DJJ; Veeger, H.E.J.

    2016-01-01

    Quantitative assessment of an athlete׳s individual wheelchair mobility performance is one prerequisite needed to evaluate game performance, improve wheelchair settings and optimize training routines. Inertial Measurement Unit (IMU) based methods can be used to perform such quantitative assessment,

  14. 78 FR 39649 - Physical Medicine Devices; Reclassification of Stair-Climbing Wheelchairs; Correction

    Science.gov (United States)

    2013-07-02

    ... of Stair-Climbing Wheelchairs; Correction AGENCY: Food and Drug Administration, HHS. ACTION: Proposed...-climbing wheelchairs. The document was published with typographical errors in the DATES section of the...

  15. Scapulothoracic and Glenohumeral Kinematics During Daily Tasks in Users of Manual Wheelchairs.

    Science.gov (United States)

    Zhao, Kristin D; Van Straaten, Meegan G; Cloud, Beth A; Morrow, Melissa M; An, Kai-Nan; Ludewig, Paula M

    2015-01-01

    Rates of shoulder pain in individuals who use manual wheelchairs (MWCs) as their primary means of mobility have been reported to be as high as 70% during activities of daily living. Current prevailing thought is that mechanical impingement of the soft tissues that reside within the subacromial space between the humeral head and coracoacromial arch is a major contributor to the shoulder pain in users of MWCs. The subacromial space size is directly related to the kinematics at the shoulder joint. Yet to be answered are questions about which common daily tasks are characterized by the most potentially detrimental kinematics. The purpose of this analysis was to quantify and compare potentially detrimental kinematics in three common tasks performed by individuals with spinal cord injury and shoulder pain. These data will add to the body of knowledge and test common assumptions about relative risk of tasks. A cross-sectional study of 15 MWC users with shoulder pain. Electromagnetic surface sensor measures of mean and peak scapulothoracic (ST) internal and downward rotation, anterior tilt, and glenohumeral (GH) internal rotation were compared across propulsion, weight relief, and scapular plane abduction tasks using one-way repeated-measure ANOVA. Statistical differences were observed between the tasks for all rotations. Mean ST anterior tilt was greater in weight relief and propulsion than during scapular plane abduction (24°, 23°, and 13° of anterior tilt, respectively). Mean GH axial rotation during weight relief was more internally rotated than during propulsion and scapular plane abduction (9°, 26°, and 51° of external rotation, respectively). Surface-based measures of kinematics are subject to skin motion artifact, especially in translation which was not addressed in this study. Each task presented with specific variables that might contribute to risk of developing shoulder "impingement" and pain. These data may assist therapists in their assessment of

  16. Fusion for Space Propulsion

    Science.gov (United States)

    Thio, Y. C. Francis; Schmidt, George R.; Santarius, John F.; Turchi, Peter J.; Siemon, Richard E.; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    The need for fusion propulsion for interplanetary flights is discussed. For a propulsion system, there are three important system attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For efficient and affordable human exploration of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion obviously cannot meet the requirement in propellant exhaust velocity. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the fission energy to heat a low atomic weight propellant produces propellant velocity of the order of 10 kinds. Alternatively the fission energy can be converted into electricity that is used to accelerate particles to high exhaust velocity. However, the necessary power conversion and conditioning equipment greatly increases the mass of the propulsion system. Fundamental considerations in waste heat rejection and power conditioning in a fission electric propulsion system place a limit on its jet specific power to the order of about 0.2 kW/kg. If fusion can be developed for propulsion, it appears to have the best of all worlds - it can provide the largest absolute amount of energy, the propellant exhaust velocity (> 100 km/s), and the high specific jet power (> 10 kW/kg). An intermediate step towards fusion propulsion might be a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. There are similarities as well as differences between applying fusion to propulsion and to terrestrial electrical power generation. The similarities are the underlying plasma and fusion physics, the enabling component technologies, the computational and the diagnostics capabilities. These physics and

  17. The oxygen uptake-heart rate relationship in trained female wheelchair athletes.

    Science.gov (United States)

    Goosey-Tolfrey, Victoria Louise; Tolfrey, Keith

    2004-05-01

    We examined the relationship between the percentage of peak heart rate (HR) and the percentage of peak oxygen uptake VO2 during steady-rate incremental wheelchair propulsion in 10 trained female wheelchair athletes (WAs) to determine the appropriateness of using American College of Sports Medicine (ACSM) target HRs for training prescription. Oxygen uptake was calculated during each submaximal exercise stage, and HR was monitored continuously. Peak VO2 was determined with the use of a separate protocol. Linear regression equations of percentage of peak HR versus percentage of peak VO2 were measured for each participant. Subsequently, we calculated the percentage of peak HR values corresponding with 40%, 60%, 80%, and 85% peak VO2. The linear regression formula (derived as the group mean of the slope and intercept terms determined from each individual participant) was % peak HR = 0.652 x % peak VO2 + 35.2 (standard error of the estimate [SEE] 3.41). The group mean of the individual correlation coefficients for the VO2-HR relationship was r = 0.973. The percentage peaks of HRs for the WAs were slightly, though not significantly, greater than those suggested by the ACSM across the exercise intensity continuum. These findings suggest that training programs prescribed on the basis of ACSM target HR guidelines need not be altered for trained female WAs with lesions of T6 and below. Notably, the discrepancy between the WA values and the population norm (ACSM) decreased from 6% at 40% peak VO2 (i.e., 61% vs. 55%) to <1% at 85% peak VO2 (i.e., 90.6% vs. 90.0%). This discrepancy indicates a tendency for the use of percentage of HR peak at the lower exercise intensities to slightly underestimate the relative exercise intensity (i.e., percentage of peak VO2) in the WA population.

  18. Physical and Leisure Activity in Older Community-Dwelling Canadians Who Use Wheelchairs: A Population Study

    OpenAIRE

    Best, Krista L.; Miller, William C.

    2011-01-01

    Background. Physical and leisure activities are proven health promotion modalities and have not been examined in older wheelchair users. Main Objectives. Examine physical and leisure activity in older wheelchair users and explore associations between wheelchair use and participation in physical and leisure activity, and wheelchair use, physical and leisure activity, and perceived health. Methods. 8301 Canadians ≥60 years of age were selected from the Canadian Community Health Survey. Sociodem...

  19. Explosive strength training improves speed and agility in wheelchair basketball athletes

    OpenAIRE

    Ozmen,Tarik; Yuktasir,Bekir; Yildirim,Necmiye Un; Yalcin,Birol; Willems,Mark ET

    2014-01-01

    INTRODUCTION: Wheelchair basketball is a paralympic sport characterized by intermittent high-intensity activities that require explosive strength and speed. OBJECTIVE: To investigate the effect of explosive strength training on speed and agility performance in wheelchair basketball players. METHODS: Ten male wheelchair basketball players (Mage=31±4 yrs) were divided into two groups [i.e. explosive strength training (ES); control (CN)] based on International Wheelchair Basketball Fede...

  20. Design and development of solar power-assisted manual/electric wheelchair

    OpenAIRE

    Chi-Sheng Chien, MD; Tung-Yung Huang, PhD; Tze-Yuan Liao, PhD; Tsung-Yuan Kuo, PhD; Tzer-Min Lee, PhD

    2015-01-01

    Wheelchairs are an essential assistive device for many individuals with injury or disability. Manual wheelchairs provide a relatively low-cost solution to the mobility needs of such individuals. Furthermore, they provide an effective means of improving the user’s cardiopulmonary function and upper-limb muscle strength. However, manual wheelchairs have a gross loss of mechanical efficiency, and thus the risk of user fatigue and upper-limb injury is increased. Electric-powered wheelchairs reduc...

  1. Laser space propulsion overview

    Science.gov (United States)

    Phipps, Claude; Luke, James; Helgeson, Wesley

    2007-03-01

    In this paper, we review the history of laser space propulsion from its earliest theoretical conceptions to modern practical applicatons. Applications begin with the "Lightcraft" flights of Myrabo and include practical thrusters for satellites now completing development as well as proposals for space debris removal and direct launch of payloads into orbit. We consider laser space propulsion in the most general sense, in which laser radiation is used to propel a vehicle in space. In this sense, the topic includes early proposals for pure photon propulsion, laser ablation propulsion, as well as propulsion using lasers to detonate a gas, expel a liquid, heat and expel a gas, or even to propagate power to a remote conventional electric thruster. We also discuss the most recent advances in LSP. For the first time, it is possible to consider space propulsion engines which exhibit thrust of one to several newtons while simultaneously delivering 3,000 seconds, or greater, specific impulse. No other engine concept can do both in a compact format. These willl use onboard, rather than remote, lasers. We will review the concept of chemically augmented electric propulsion, which can provide overall thrust efficiency greater than unity while maintaining very low mass to power ratio, high mean time to failure and broad operating range. The main advantage of LSP is exhaust velocity which can be instantaneously varied from 2km/s to 30km/s, simply by varying laser pulsewidth and focal spot size on target. The laser element will probably be a diode-pumped, fiber master-oscillator-power-amplifier (MOPA) system. Liquid fuels are necessary for volumetric efficiency and reliable performance at the multi-kW optical power levels required for multi-N thrust.

  2. Do field position and playing standard influence athlete performance in wheelchair basketball?

    NARCIS (Netherlands)

    de Witte, A.M.H.; Hoozemans, M.J.M.; Berger, M.A.; van der Woude, L.H.V.; Veeger, H.E.J.

    2016-01-01

    Improved understanding of mobility performance in wheelchair basketball is required to increase game performance. The aim of this study was to quantify the wheelchair-athlete activities of players in different field positions and of different playing standard during wheelchair basketball matches.

  3. Wheel skid correction is a prerequisite to reliably measure wheelchair sports kinematics based on inertial sensors

    NARCIS (Netherlands)

    Van der Slikke, R.M.A.; Berger, M.A.M.; Bregman, D.J.J.; Veeger, H.E.J.

    2015-01-01

    Accurate knowledge of wheelchair kinematics during a match could be a significant factor in performance improvement in wheelchair basketball. To date, most systems for measuring wheelchair kinematics are not suitable for match applications or lack detail in key kinematic outcomes. This study

  4. Relationship between Functional Classification Levels and Anaerobic Performance of Wheelchair Basketball Athletes

    Science.gov (United States)

    Molik, Bartosz; Laskin, James J.; Kosmol, Andrzej; Skucas, Kestas; Bida, Urszula

    2010-01-01

    Wheelchair basketball athletes are classified using the International Wheelchair Basketball Federation (IWBF) functional classification system. The purpose of this study was to evaluate the relationship between upper extremity anaerobic performance (AnP) and all functional classification levels in wheelchair basketball. Ninety-seven male athletes…

  5. Aerobic, Anaerobic, and Skill Performance with Regard to Classification in Wheelchair Rugby Athletes

    Science.gov (United States)

    Morgulec-Adamowicz, Natalia; Kosmol, Andrzej; Molik, Bartosz; Yilla, Abu B.; Laskin, James J.

    2011-01-01

    The purpose of the study was to examine the sport-specific performance of wheelchair rugby players with regard to their classification. A group of 30 male athletes from the Polish Wheelchair Rugby League participated in the study. The seven International Wheelchair Rugby Federation classes were collapsed into four groups. Standardized measures of…

  6. A sports wheelchair for low-income countries.

    Science.gov (United States)

    Authier, Erica L; Pearlman, Jon; Allegretti, Ana L; Rice, Ian; Cooper, Rory A

    Appropriate wheelchairs for basic mobility needs are still not commonly available in low-income countries, although several organizations are working toward this goal. After basic mobility is secured it is important to provide more diverse assistive technology to allow people with disabilities to more completely participate in society and live healthy lives. Our goal was to design an affordable sports wheelchair that would allow individuals in low-income countries to participate in basketball. Design requirements established for the sports wheelchair included: removable anti-tippers, adjustable tension backrest, 24'' wheels, adjustable seat dump, variable camber, 4'' casters, fore-aft axle position, removable bumpers, height adjustable footrest, four wheels, single anti-tipper (pivot), cost less than $125 without wheels, 16'' seat width and backrest height, and nylon upholstery. The wheelchair was designed using 3D modeling, standard materials, and standard tools. An affordable wheelchair, versatile enough to be used for a variety of sports and even everyday use, was designed and prototyped successfully. Documentation for the design including step-by-step directions, engineering drawings, and photographs are available at the Human Engineering Research Laboratories website (http://www.herlpitt.org/intw.htm). Future work on the prototype should include design refinement including adaptations for other sports, and standards testing.

  7. Towards an intelligent wheelchair system for users with cerebral palsy.

    Science.gov (United States)

    Montesano, Luis; Díaz, Marta; Bhaskar, Sonu; Minguez, Javier

    2010-04-01

    This paper describes and evaluates an intelligent wheelchair, adapted for users with cognitive disabilities and mobility impairment. The study focuses on patients with cerebral palsy, one of the most common disorders affecting muscle control and coordination, thereby impairing movement. The wheelchair concept is an assistive device that allows the user to select arbitrary local destinations through a tactile screen interface. The device incorporates an automatic navigation system that drives the vehicle, avoiding obstacles even in unknown and dynamic scenarios. It provides the user with a high degree of autonomy, independent from a particular environment, i.e., not restricted to predefined conditions. To evaluate the rehabilitation device, a study was carried out with four subjects with cognitive impairments, between 11 and 16 years of age. They were first trained so as to get acquainted with the tactile interface and then were recruited to drive the wheelchair. Based on the experience with the subjects, an extensive evaluation of the intelligent wheelchair was provided from two perspectives: 1) based on the technical performance of the entire system and its components and 2) based on the behavior of the user (execution analysis, activity analysis, and competence analysis). The results indicated that the intelligent wheelchair effectively provided mobility and autonomy to the target population.

  8. Manual Wheelchair Use: Bouts of Mobility in Everyday Life

    Directory of Open Access Journals (Sweden)

    Sharon Eve Sonenblum

    2012-01-01

    Full Text Available Background. This study aimed to describe how people move about in manual wheelchairs (MWCs during everyday life by evaluating bouts of mobility or continuous periods of movement. Methods. A convenience sample of 28 MWC users was recruited. Participants' everyday mobility was measured using a wheel-mounted accelerometer and seat occupancy switch for 1-2 weeks. Bouts of mobility were recorded and characterized. Results. Across 29,200 bouts, the median bout lasted 21 seconds and traveled 8.6 m at 0.43 m/s. 85% of recorded bouts lasted less than 1 minute and traveled less than 30 meters. Participants' daily wheelchair activity included 90 bouts and 1.6 km over 54 minutes. Average daily occupancy time was 11 hours during which participants wheeled 10 bouts/hour and spent 10% of their time wheeling. Spearman-Brown Prophecy analysis suggested that 7 days were sufficient to achieve a reliability of 0.8 for all bout variables. Conclusions. Short, slow bouts dominate wheelchair usage in a natural environment. Therefore, clinical evaluations and biomechanical research should reflect this by concentrating on initiating movement, maneuvering wheelchairs, and stopping. Bouts of mobility provide greater depth to our understanding of wheelchair use and are a more stable metric (day-to-day than distance or time wheeled.

  9. An Omnidirectional Stereo Vision-Based Smart Wheelchair

    Directory of Open Access Journals (Sweden)

    Yutaka Satoh

    2007-06-01

    Full Text Available To support safe self-movement of the disabled and the aged, we developed an electric wheelchair that realizes the functions of detecting both the potential hazards in a moving environment and the postures and gestures of a user by equipping an electric wheelchair with the stereo omnidirectional system (SOS, which is capable of acquiring omnidirectional color image sequences and range data simultaneously in real time. The first half of this paper introduces the SOS and the basic technology behind it. To use the multicamera system SOS on an electric wheelchair, we developed an image synthesizing method of high speed and high quality and the method of recovering SOS attitude changes by using attitude sensors is also introduced. This method allows the SOS to be used without being affected by the mounting attitude of the SOS. The second half of this paper introduces the prototype electric wheelchair actually manufactured and experiments conducted using the prototype. The usability of the electric wheelchair is also discussed.

  10. Nuclear-electric propulsion - Manned Mars propulsion options

    Science.gov (United States)

    Palaszewski, Bryan; Brophy, John; King, David

    1989-01-01

    Nuclear-electric propulsion can significantly reduce the launch mass for manned Mars missions. By using high-specific-impulse (lsp) electric propulsion systems with advanced nuclear reactors, the total mass-to-orbit for a series of manned Mars flight is reduced. Propulsion technologies required for the manned Mars mission are described. Multi-megawatt Ion and Magneto-Plasma-Dynamic (MPD) propulsion thrusters, Power-Processing Units and nuclear power source are needed. Xenon (Xe)-Ion and MPD thruster performance are detailed. Mission analyses for several Mars mission options are addressed. Both MPD and Ion propulsion were investigated. A four-megawatt propulsion system power level was assumed. Mass comparisons for all-chemical oxygen/hydrogen propulsion missions and combined chemical and nuclear-electric propulsion Mars fleets are included. With fleets of small nuclear-electric vehicles, short trip times to Mars are also enabled.

  11. Using Self-Reliance Factors to Decide How to Share Control Between Human Powered Wheelchair Drivers and Ultrasonic Sensors.

    Science.gov (United States)

    Sanders, David A

    2017-08-01

    A shared-control scheme for a powered wheelchair is presented. The wheelchair can be operated by a wheelchair driver using a joystick, or directed by a sensor system, or control can be combined between them. The wheelchair system can modify direction depending on the local environment. Sharing the control allows a disabled wheelchair driver to drive safely and efficiently. The controller automatically establishes the control gains for the sensor system and the human driver by calculating a self-reliance factor for the wheelchair driver. The sensor system can influence the motion of the wheelchair to compensate for some deficiency in a disabled driver. Practical tests validate the proposed techniques and designs.

  12. Airbreathing Propulsion An Introduction

    CERN Document Server

    Bose, Tarit

    2012-01-01

    Airbreathing Propulsion covers the physics of combustion, fluid and thermo-dynamics, and structural mechanics of airbreathing engines, including piston, turboprop, turbojet, turbofan, and ramjet engines. End-of-chapter exercises allow the reader to practice the fundamental concepts behind airbreathing propulsion, and the included PAGIC computer code will help the reader to examine the relationships between the performance parameters of different engines. Large amounts of data on many different piston, turbojet, and turboprop engines have been compiled for this book and are included as an appendix. This textbook is ideal for senior undergraduate and graduate students studying aeronautical engineering, aerospace engineering, and mechanical engineering.

  13. Propulsion controlled aircraft computer

    Science.gov (United States)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  14. Extending Teach and Repeat to Pivoting Wheelchairs

    Directory of Open Access Journals (Sweden)

    Guillermo Del Castillo

    2003-02-01

    Full Text Available The paper extends the teach-and-repeat paradigm that has been successful for the control of holonomic robots to nonholonomic wheelchairs which may undergo pivoting action over the course of their taught movement. Due to the nonholonomic nature of the vehicle kinematics, estimation is required -- in the example given herein, based upon video detection of wall-mounted cues -- both in the teaching and the tracking events. In order to accommodate motion that approaches pivoting action as well as motion that approaches straight-line action, the estimation equations of the Extended Kalman Filter and the control equations are formulated using two different definitions of a nontemporal independent variable. The paper motivates the need for pivoting action in real-life settings by reporting extensively on the abilities and limitations of estimation-based teach-and-repeat action where pivoting and near-pivoting action is disallowed. Following formulation of the equations in the near-pivot mode, the paper reports upon experiments where taught trajectories which entail a seamless mix of near-straight and near-pivot action are tracked.

  15. Space transportation propulsion USSR launcher technology, 1990

    Science.gov (United States)

    1991-01-01

    Space transportation propulsion U.S.S.R. launcher technology is discussed. The following subject areas are covered: Energia background (launch vehicle summary, Soviet launcher family) and Energia propulsion characteristics (booster propulsion, core propulsion, and growth capability).

  16. Real-time model based electrical powered wheelchair control.

    Science.gov (United States)

    Wang, Hongwu; Salatin, Benjamin; Grindle, Garrett G; Ding, Dan; Cooper, Rory A

    2009-12-01

    The purpose of this study was to evaluate the effects of three different control methods on driving speed variation and wheel slip of an electric-powered wheelchair (EPW). A kinematic model as well as 3D dynamic model was developed to control the velocity and traction of the wheelchair. A smart wheelchair platform was designed and built with a computerized controller and encoders to record wheel speeds and to detect the slip. A model based, a proportional-integral-derivative (PID) and an open-loop controller were applied with the EPW driving on four different surfaces at three specified speeds. The speed errors, variation, rise time, settling time and slip coefficient were calculated and compared for a speed step-response input. Experimental results showed that model based control performed best on all surfaces across the speeds.

  17. Epidemiology of Medicare abuse: the example of power wheelchairs.

    Science.gov (United States)

    Goodwin, James S; Nguyen-Oghalai, Tracy U; Kuo, Yong-Fang; Ottenbacher, Kenneth J

    2007-02-01

    To determine the effect of neighborhood ethnic composition on power wheelchair prescriptions. The 5% noncancer sample of Medicare recipients in the Surveillance, Epidemiology and End Results (SEER)-Medicare linked database, from 1994 to 2001. SEER regions. Individuals covered by Medicare living in SEER regions without a cancer diagnosis. Individual characteristics (age, sex, ethnicity, justifying diagnosis, and comorbidity), primary diagnoses, neighborhood characteristics (percentage black, percentage Hispanic, percentage with multilevel, multivariate analyses, individuals living in neighborhoods with higher percentages of blacks or Hispanics were more likely to receive power wheelchairs (odds ratios=1.09 for each 10% increase in black residents and 1.23 for each 10% increase in Hispanic residents) after controlling for ethnicity and other characteristics at the individual level. These results support allegations that marketers promoting power wheelchairs have specifically targeted minority neighborhoods.

  18. Obstacle avoidance for power wheelchair using bayesian neural network.

    Science.gov (United States)

    Trieu, Hoang T; Nguyen, Hung T; Willey, Keith

    2007-01-01

    In this paper we present a real-time obstacle avoidance algorithm using a Bayesian neural network for a laser based wheelchair system. The raw laser data is modified to accommodate the wheelchair dimensions, allowing the free-space to be determined accurately in real-time. Data acquisition is performed to collect the patterns required for training the neural network. A Bayesian frame work is applied to determine the optimal neural network structure for the training data. This neural network is trained under the supervision of the Bayesian rule and the obstacle avoidance task is then implemented for the wheelchair system. Initial results suggest this approach provides an effective solution for autonomous tasks, suggesting Bayesian neural networks may be useful for wider assistive technology applications.

  19. A Multi-Agent Control Architecture for a Robotic Wheelchair

    Directory of Open Access Journals (Sweden)

    C. Galindo

    2006-01-01

    Full Text Available Assistant robots like robotic wheelchairs can perform an effective and valuable work in our daily lives. However, they eventually may need external help from humans in the robot environment (particularly, the driver in the case of a wheelchair to accomplish safely and efficiently some tricky tasks for the current technology, i.e. opening a locked door, traversing a crowded area, etc. This article proposes a control architecture for assistant robots designed under a multi-agent perspective that facilitates the participation of humans into the robotic system and improves the overall performance of the robot as well as its dependability. Within our design, agents have their own intentions and beliefs, have different abilities (that include algorithmic behaviours and human skills and also learn autonomously the most convenient method to carry out their actions through reinforcement learning. The proposed architecture is illustrated with a real assistant robot: a robotic wheelchair that provides mobility to impaired or elderly people.

  20. Energy Conversion in Laser Propulsion

    National Research Council Canada - National Science Library

    Larson, C

    2001-01-01

    Analysis of energy conversion in laser propulsion is reported and compared to experimental studies of a laboratory scale propulsion device that absorbs laser energy and converts that energy to propellant kinetic energy...

  1. Shoulder pain: a comparison of wheelchair basketball players with trunk control and without trunk control.

    Science.gov (United States)

    Yildirim, Necmiye Un; Comert, Esra; Ozengin, Nuriye

    2010-01-01

    The purpose of this study was to compare shoulder pain between wheelchair basketball players with trunk control and wheelchair basketball players without trunk control. Players were evaluated according the International Wheelchair Basketball Federation (IWBF) classification system. The study group comprised 60 wheelchair basketball players, who were rated according to the International Wheelchair Basketball Federation classification system. Players were divided into two groups according to their trunk control. Study participants completed an anonymous survey that included demographic data, medical history data, and the Wheelchair User's Shoulder Pain Index (WUSPI). There was no statistically significant difference between the two groups based on the number of years of wheelchair use, active sport years, weekly working hours, and weekly training hours (p> 0.05). Statistically significant differences were found between wheelchair basketball players with trunk control and wheelchair basketball players with trunk control with respect to the duration of their disability, the daily number of transfers made to wheelchair, and Performance Corrected Wheelchair User's Shoulder Pain Index (PC-WUSPI) score (pwheelchair basketball players must be analyzed. Trunk stabilization is the key factor affecting the function of the shoulder and is of primary importance for appropriate loading of the shoulder joint's many forms of articulation.

  2. Mobile Augmented Reality enhances indoor navigation for wheelchair users

    Directory of Open Access Journals (Sweden)

    Luciene Chagas de Oliveira

    Full Text Available Introduction: Individuals with mobility impairments associated with lower limb disabilities often face enormous challenges to participate in routine activities and to move around various environments. For many, the use of wheelchairs is paramount to provide mobility and social inclusion. Nevertheless, they still face a number of challenges to properly function in our society. Among the many difficulties, one in particular stands out: navigating in complex internal environments (indoors. The main objective of this work is to propose an architecture based on Mobile Augmented Reality to support the development of indoor navigation systems dedicated to wheelchair users, that is also capable of recording CAD drawings of the buildings and dealing with accessibility issues for that population. Methods Overall, five main functional requirements are proposed: the ability to allow for indoor navigation by means of Mobile Augmented Reality techniques; the capacity to register and configure building CAD drawings and the position of fiducial markers, points of interest and obstacles to be avoided by the wheelchair user; the capacity to find the best route for wheelchair indoor navigation, taking stairs and other obstacles into account; allow for the visualization of virtual directional arrows in the smartphone displays; and incorporate touch or voice commands to interact with the application. The architecture is proposed as a combination of four layers: User interface; Control; Service; and Infrastructure. A proof-of-concept application was developed and tests were performed with disable volunteers operating manual and electric wheelchairs. Results The application was implemented in Java for the Android operational system. A local database was used to store the test building CAD drawings and the position of fiducial markers and points of interest. The Android Augmented Reality library was used to implement Augmented Reality and the Blender open source

  3. Prototype for Managing the Wheelchair Movements by Accelerometry

    Directory of Open Access Journals (Sweden)

    Daniel Alves FUSCO

    2011-03-01

    Full Text Available This article describes the development stages and the obtained results in a design and testing of a wheelchair controlled by bi-axial accelerometers placed at the user head top. This proposed system has the primary goal to facilitate the handicapped persons locomotion who has only the head movement or difficulty moving the hand-arm segment, thus presenting a different control type of most motorized wheelchairs in market. The results showed that low cost acceleration sensors are efficient to assistive technology systems.

  4. To study propulsion drives

    OpenAIRE

    Rassylkin, Anton; Vodovozov, Valery

    2013-01-01

    This paper describes a test bench developed to study and monitor the propulsion drives of electric vehicles at Tallinn University of Technology. The composition and performance of the setup are explained. The charging process of the supercapacitor bank is described as an example of the test bench application. The developed simulation model of the supercapacitor bank is presented and discussed.

  5. Advanced cryo propulsion systems

    Science.gov (United States)

    Tabata, William K.

    1991-01-01

    The following topics are presented in viewgraph form: (1) advanced space engine (ASE) chronology; (2) an ASE description; (3) a single expander; (4) a dual expander; (5) split expander; (6) launch vehicle start; (7) space start; (8) chemical transfer propulsion; and (9) an advanced expander test bed.

  6. The effect of short-duration sub-maximal cycling on balance in single-limb stance in patients with anterior cruciate ligament injury: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Roberts David

    2004-11-01

    Full Text Available Abstract Background It has previously been shown that an anterior cruciate ligament (ACL injury may lead to impaired postural control, and that the ability to maintain postural control is decreased by fatigue in healthy subjects. To our knowledge, no studies have reported the effect of fatigue on postural control in subjects with ACL injury. This study was aimed at examining the effect of fatigue on balance in single-limb stance in subjects with ACL injury, and to compare the effects, and the ability to maintain balance, with that of a control group of uninjured subjects. Methods Thirty-six patients with unilateral, non-operated, non-acute ACL injury, and 24 uninjured subjects were examined with stabilometry before (pre-exercise and immediately after (post-exercise short-duration, sub-maximal cycling. In addition, the post-exercise measurements were compared, to evaluate the instantaneous ability to maintain balance and any possible recovery. The amplitude and average speed of center of pressure movements were registered in the frontal and sagittal planes. The paired t-test was used for the intra-group comparisons, and the independent t-test for the inter-group comparisons, with Bonferroni correction for multiple comparisons. Results No differences were found in the effects of exercise between the patients and the controls. Analysis of the post-exercise measurements revealed greater effects or a tendency towards greater effects on the injured leg than in the control group. The average speed was lower among the patients than in the control group. Conclusions The results of the present study showed no differences in the effects of exercise between the patients and the controls. However, the patients seemed to react differently regarding ability to maintain balance in single-limb stance directly after exercise than the control group. The lower average speed among the patients may be an expression of different neuromuscular adaptive strategies than

  7. Physical performance and cardiovascular and metabolic adaptation of elite female wheelchair basketball players in wheelchair ergometry and in competition.

    Science.gov (United States)

    Schmid, A; Huonker, M; Stober, P; Barturen, J M; Schmidt-Trucksäss, A; Dürr, H; Völpel, H J; Keul, J

    1998-01-01

    Spinal cord injury leads to a pronounced reduction of cardiovascular, pulmonary, and metabolic ability. Physical activity, up to and including high-performance sports, has obtained importance in the course of rehabilitation and the postclinical phase. Thirteen elite female wheelchair basketball players from the German National Basketball Team and 10 female sedentary spinal cord-injured persons were examined in the study. Heart volume was measured by an echocardiography. All subjects underwent a graded exercise test on a wheelchair ergometer. Additionally, heart rate, lactate, and player points were measured during a competitive basketball game in wheelchair basketball players. Cardiac dimensions were larger for spinal cord-injured wheelchair basketball players (620.3 ml; 9.6 ml x kg(-1)) in comparison with spinal cord-injured persons (477.4 ml; 8.2 ml x kg(-1)) but did not exceed the heart volume of untrained nonhandicapped persons. In contrast, athletes with amputations or those having had poliomyelitis reached training-induced cardiac hypertrophy in relation to body mass (713.7 ml; 13.2 ml x kg(-1)), as observed in nonhandicapped athletes. During graded wheelchair ergometry, wheelchair basketball players showed a higher maximal work rate (59.9 v 45.5 W), maximal oxygen consumption (33.7 v 18.3 ml x min(-1) x kg(-1)), and maximal lactate (9.1 v 5.47 mmol x l(-1)) without a difference in maximal heart rate and workload at AT4 than did spinal cord-injured persons. The average heart rate during the wheelchair basketball game was 151 x min(-1), and the lactate concentration was 1.92 mmol x l(-1). Female athletes with a less severe handicap and higher maximal oxygen consumption during the graded exercise test reached a higher game level in the evaluation. During the competitive basketball game, high cardiovascular stress was observed, indicating a fast aerobic metabolism; the anaerobic lactic acid capacity played a subordinate role. Wheelchair basketball is an

  8. Quantitative evaluation of trunk muscle strength in wheelchair basketball players

    Directory of Open Access Journals (Sweden)

    Sileno da Silva Santos

    2016-06-01

    Full Text Available Abstract Trunk muscle strength affects trunk controlling playing an important role in performance and to define the classes of wheelchair basketball players. Trunk control capacity differs among players and quantitative assessments of trunk muscle strength have not been investigated. The aim of this study was to identify and correlate quantitative measures of trunk muscle strength with the wheelchair basketball players' classification. Forty-two male wheelchair basketball players with spinal cord injury, amputation, post-poliomyelitis sequelae, and cerebral palsy had their trunk extension and flexion strength evaluated with isokinetic dynamometer. The classes 1.0, 2.0, 3.0, and 4.0 were considered for statistical analysis. Comparison of trunk muscle strength differed significantly between classes: 1.0 and 3.0; 1.0 and 4.0; 2.0 and 3.0; and 2.0 and 4.0. High correlation was found between the trunk muscle strength and players' classes. The findings of the present study showed a strong correlation of trunk muscle strength and wheelchair basketball classes being able to distinguish players in their classes. However, this quantitative method of evaluation of the trunk muscle strength cannot be solely used to make a decision on the full trunk control.

  9. Current Perspectives on Profiling and Enhancing Wheelchair Court Sport Performance.

    Science.gov (United States)

    Paulson, Thomas; Goosey-Tolfrey, Victoria

    2017-03-01

    Despite the growing interest in Paralympic sport, the evidence base for supporting elite wheelchair sport performance remains in its infancy when compared with able-bodied (AB) sport. Subsequently, current practice is often based on theory adapted from AB guidelines, with a heavy reliance on anecdotal evidence and practitioner experience. Many principles in training prescription and performance monitoring with wheelchair athletes are directly transferable from AB practice, including the periodization and tapering of athlete loads around competition, yet considerations for the physiological consequences of an athlete's impairment and the interface between athlete and equipment are vital when targeting interventions to optimize in-competition performance. Researchers and practitioners are faced with the challenge of identifying and implementing reliable protocols that detect small but meaningful changes in impairment-specific physical capacities and on-court performance. Technologies to profile both linear and rotational on-court performance are an essential component of sport-science support to understand sport-specific movement profiles and prescribe training intensities. In addition, an individualized approach to the prescription of athlete training and optimization of the "wheelchair-user interface" is required, accounting for an athlete's anthropometrics, sports classification, and positional role on court. In addition to enhancing physical capacities, interventions must focus on the integration of the athlete and his or her equipment, as well as techniques for limiting environmental influence on performance. Taken together, the optimization of wheelchair sport performance requires a multidisciplinary approach based on the individual requirements of each athlete.

  10. Multidimensional Self-Efficacy and Affect in Wheelchair Basketball Players

    Science.gov (United States)

    Martin, Jeffrey J.

    2008-01-01

    In the current study, variables grounded in social cognitive theory with athletes with disabilities were examined. Performance, training, resiliency, and thought control self-efficacy, and positive (PA) and negative (NA) affect were examined with wheelchair basketball athletes (N = 79). Consistent with social cognitive theory, weak to strong…

  11. Intelligent Control Wheelchair Using a New Visual Joystick

    Directory of Open Access Journals (Sweden)

    Yassine Rabhi

    2018-01-01

    Full Text Available A new control system of a hand gesture-controlled wheelchair (EWC is proposed. This smart control device is suitable for a large number of patients who cannot manipulate a standard joystick wheelchair. The movement control system uses a camera fixed on the wheelchair. The patient’s hand movements are recognized using a visual recognition algorithm and artificial intelligence software; the derived corresponding signals are thus used to control the EWC in real time. One of the main features of this control technique is that it allows the patient to drive the wheelchair with a variable speed similar to that of a standard joystick. The designed device “hand gesture-controlled wheelchair” is performed at low cost and has been tested on real patients and exhibits good results. Before testing the proposed control device, we have created a three-dimensional environment simulator to test its performances with extreme security. These tests were performed on real patients with diverse hand pathologies in Mohamed Kassab National Institute of Orthopedics, Physical and Functional Rehabilitation Hospital of Tunis, and the validity of this intelligent control system had been proved.

  12. Socialization of elite wheelchair tennis players in South Africa | Roux ...

    African Journals Online (AJOL)

    The purpose of this exploratory study was therefore to collect qualitative data from elite national wheelchair tennis players (n=8). This data was gathered through in-depth semi-structured interviews regarding their socialization processes into and via sport. From the results three main themes were identified, namely, 1.

  13. Mouse for Computer Control from the Joystick of the Wheelchair

    Directory of Open Access Journals (Sweden)

    Roberto Casas

    2012-11-01

    Full Text Available Becoming autonomous is one of the biggest challenges for many people with disabilities. Increasing their autonomy usually involves the use of a wheelchair and any kind of digital assistant, such as a computer or a tablet, to communicate, to work or even for leisure. In such a situation, those people are obliged to use two different human interfaces to move a pointer and to drive the wheelchair. A joystick is the most common option to control a wheelchair. On the other hand, there are many different adapted interfaces to emulate the use of a mouse. This paper presents a system, BJoy Ring mouse, which captures the motion of the joystick on a wheelchair. The captured signal is used to move the cursor or the pointer of any digital device including an USB port. This system avoids any mechanical or electronic change in the joystick to keep its original safety and warranty. Communication between the device and the computer (or any other digital assistant uses the USB protocol, although it could be easily improved to a Bluetooth wireless connection. Validation tests with real users proved this system to be useful aid for people with motor disabilities.

  14. Locally manufactured wheelchairs in Tanzania – are users satisfied ...

    African Journals Online (AJOL)

    ditions, with neurology, communicable diseases, and road .... the case of transportation where an appreciable number ... vice related aspects. This suggests that the locally manufactured wheelchairs were perceived to be appropriate in meeting the needs of the users. This may not necessarily indicate that the reso- lution at ...

  15. Shoulder complaints in wheelchair athletes : A systematic review

    NARCIS (Netherlands)

    Heyward, Omar W.; Vegter, Riemer J. K.; de Groot, Sonja; van der Woude, Lucas H. V.

    2017-01-01

    Background: In recent years the popularity of disabled sports and competition among disabled athletes has grown considerably. With this rise in exposure of, and participation in wheelchair sports comes an increase in related stressors, including musculoskeletal load. External mechanical loading may

  16. Recording gaze trajectory of wheelchair users by a spherical camera.

    Science.gov (United States)

    Li, Shigang; Fujiura, Tatsuya; Nakanishi, Isao

    2017-07-01

    Wheelchairs are widely used in the facilities of rehabilitation. In this paper, we propose a method of recording the gaze trajectory of wheelchair users by using a spherical camera mounted on the wheelchairs. A spherical camera has a full field of view and can observe the entire surrounding scenes. First, the gaze point of a user sitting on a wheelchair is estimated from the corneal reflection image observed by a wearable eye camera. Then, the gaze point is mapped onto the full-view image captured by the spherical camera via feature matching. Since it is not guaranteed that the gaze point in an eye image is a distinctive feature point, the matching of a gaze point between these two images cannot be carried out directly. To cope with this problem, we use a coarse-to-fine approach, in which, first, distinctive feature points are used to estimate the relative orientation between the eye camera and the spherical camera, and then, the estimated relative orientation matrix is used to determine the location of gaze points. The effectiveness of the proposed method is shown by real-world experimental results.

  17. Reinforcing Zionist Ableism in Israeli Wheelchair Folk Dancing

    Science.gov (United States)

    Broyer, Nili R.

    2017-01-01

    This article examines a culturally specific case study of integrated dance. While integrated dance must constantly combat what I termed as "disdance" to earn legitimacy, each project might do this differently in its particular context. Based on documentary analysis and ethnography, I argue that in the Israeli context, wheelchair folk…

  18. Wheeled mobility skills of wheelchair basketball players: a randomized controlled study.

    Science.gov (United States)

    Saltan, Asuman; Bakar, Yeşim; Ankarali, Handan

    2017-05-01

    The aim of this study was to assess the influence of wheelchair basketball sport on the functional abilities of wheelchair users. This is a randomized controlled study. Wheelchair basketball players (n = 111) and non-player (n = 85) were included in this study. We administered the questionnaire version of the wheelchair skills test questionnaire (WST_Q), recording the participants' capacity and performance scores on each of 32 skills. Player group have the baseline values of WST_Q higher than control group. The mean total percentage score of player group was significantly greater than control group (p wheelchair basketball sport may preserve and augment functional abilities in with wheelchair user Implications for rehabilitation The skills-sports relationship is reciprocal. With increased wheelchair skills, people may be more inclined to engage in sports; subsequently, with greater sports, wheelchair skills could improve. Wheelchair mobility skills during clinical rehabilitation should reflect the daily activities and needs of each wheelchair user. WST-Q provides advantages in terms of requiring less time and material in using of clinical.

  19. Case-based reasoning emulation of persons for wheelchair navigation.

    Science.gov (United States)

    Peula, Jose Manuel; Urdiales, Cristina; Herrero, Ignacio; Fernandez-Carmona, Manuel; Sandoval, Francisco

    2012-10-01

    Testing is a key stage in system development, particularly in systems such as a wheelchair, in which the final user is typically a disabled person. These systems have stringent safety requirements, requiring major testing with many different individuals. The best would be to have the wheelchair tested by many different end users, as each disability affects driving skills in a different way. Unfortunately, from a practical point of view it is difficult to engage end users as beta testers. Hence, testing often relies on simulations. Naturally, these simulations need to be as realistic as possible to make the system robust and safe before real tests can be accomplished. This work presents a tool to automatically test wheelchairs through realistic emulation of different wheelchair users. Our approach is based on extracting meaningful data from real users driving a power wheelchair autonomously. This data is then used to train a case-based reasoning (CBR) system that captures the specifics of the driver via learning. The resulting case-base is then used to emulate the driving behavior of that specific person in more complex situations or when a new assistive algorithm needs to be tested. CBR returns user's motion commands appropriate for each specific situation to add the human component to shared control systems. The proposed system has been used to emulate several power wheelchair users presenting different disabilities. Data to create this emulation was obtained from previous wheelchair navigation experiments with 35 volunteer in-patients presenting different degrees of disability. CBR was trained with a limited number of scenarios for each volunteer. Results proved that: (i) emulated and real users returned similar paths in the same scenario (maximum and mean path deviations are equal to 23 and 10cm, respectively) and similar efficiency; (ii) we established the generality of our approach taking a new path not present in the training traces; (iii) the emulated user

  20. Shoulder complaints in wheelchair athletes: A systematic review.

    Directory of Open Access Journals (Sweden)

    Omar W Heyward

    Full Text Available In recent years the popularity of disabled sports and competition among disabled athletes has grown considerably. With this rise in exposure of, and participation in wheelchair sports comes an increase in related stressors, including musculoskeletal load. External mechanical loading may increase the risk of shoulder complaints. The objective of this literature review was to 1 identify and describe the prevalence and/or incidence of shoulder complaints in wheelchair athletes in the literature, to 2 examine the factors and underlying mechanisms that could be potentially involved, and 3 provide some insights into the development of preventative measures.A literature search was conducted using PubMed, Scopus and Embase databases, to identify relevant published articles. All articles in the English language that contained any type of shoulder complaint in relation with a wheelchair sports player, at any level of status (recreational to elite, of any sport, were included. Articles were excluded if they did not include any statistical analysis. Articles that included studies with wheelchair athletes in combination with athletes of other disability sports were excluded in order to be able to differentiate between the two. Narrative, exploratory and case studies were also excluded. Two reviewers independently assessed articles for inclusion. Thirteen articles matched the selection criteria. These were judged on their quality by use of an adapted version of the Webster checklist.Of the included studies the overall quality was low. A relatively high prevalence of complaints was found, ranging from 16% to 76%. Pain was found to be a common complaint in wheelchair athletes. Based on the current literature the cause of shoulder problems is difficult to identify and is likely multifactorial, nevertheless characteristics of the user (i.e. increased years of disability, age and BMI were shown to increase risk. Preventative measures were indistinct. There may be

  1. Wheelchair services and use outcomes: A cross-sectional survey in Kenya and the Philippines

    Directory of Open Access Journals (Sweden)

    Eva S. Bazant

    2017-01-01

    Full Text Available Background: The World Health Organisation recommends that services accompany wheelchair distribution. This study examined the relationship of wheelchair service provision in Kenya and the Philippines and wheelchair-use–related outcomes.Method: We surveyed 852 adult basic manual wheelchair users. Participants who had received services and those who had not were sought in equal numbers from wheelchair-distribution entities. Outcomes assessed were daily wheelchair use, falls, unassisted outdoor use and performance of activities of daily living (ADL. Descriptive, bivariate and multivariable regression model results are presented.Results: Conditions that led to the need for a basic wheelchair were mainly spinal cord injury, polio/post-polio, and congenital conditions. Most Kenyans reported high daily wheelchair use (60% and ADL performance (80%, while these practices were less frequent in the Philippine sample (42% and 74%, respectively. Having the wheelchair fit assessed while the user propelled the wheelchair was associated with greater odds of high ADL performance in Kenya (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.6, 5.1 and the Philippines (OR 2.8, 95% CI 1.8, 4.5. Wheelchair-related training was associated with high ADL performance in Kenya (OR 3.2, 95% CI 1.3, 8.4. In the Philippines, training was associated with greater odds of high versus no daily wheelchair use but also odds of serious versus no falls (OR 2.5, 95% CI 1.4, 4.5.Conclusion: Select services that were associated with some better wheelchair use outcomes and should be emphasised in service delivery. Service providers should be aware that increased mobility may lead to serious falls.

  2. Deuterium microbomb rocket propulsion

    Science.gov (United States)

    Winterberg, F.

    2010-01-01

    Large scale manned space flight within the solar system is still confronted with the solution of two problems: (1) A propulsion system to transport large payloads with short transit times between different planetary orbits. (2) A cost effective lifting of large payloads into earth orbit. For the solution of the first problem a deuterium fusion bomb propulsion system is proposed where a thermonuclear detonation wave is ignited in a small cylindrical assembly of deuterium with a gigavolt-multimegaampere proton beam, drawn from the magnetically insulated spacecraft acting in the ultrahigh vacuum of space as a gigavolt capacitor. For the solution of the second problem, the ignition is done by argon ion lasers driven by high explosives, with the lasers destroyed in the fusion explosion and becoming part of the exhaust.

  3. Jet propulsion without inertia

    CERN Document Server

    Spagnolie, Saverio E

    2010-01-01

    A body immersed in a highly viscous fluid can locomote by drawing in and expelling fluid through pores at its surface. We consider this mechanism of jet propulsion without inertia in the case of spheroidal bodies, and derive both the swimming velocity and the hydrodynamic efficiency. Elementary examples are presented, and exact axisymmetric solutions for spherical, prolate spheroidal, and oblate spheroidal body shapes are provided. In each case, entirely and partially porous (i.e. jetting) surfaces are considered, and the optimal jetting flow profiles at the surface for maximizing the hydrodynamic efficiency are determined computationally. The maximal efficiency which may be achieved by a sphere using such jet propulsion is 12.5%, a significant improvement upon traditional flagella-based means of locomotion at zero Reynolds number. Unlike other swimming mechanisms which rely on the presentation of a small cross section in the direction of motion, the efficiency of a jetting body at low Reynolds number increas...

  4. Hydrodynamics of Peristaltic Propulsion

    Science.gov (United States)

    Athanassiadis, Athanasios; Hart, Douglas

    2014-11-01

    A curious class of animals called salps live in marine environments and self-propel by ejecting vortex rings much like jellyfish and squid. However, unlike other jetting creatures that siphon and eject water from one side of their body, salps produce vortex rings by pumping water through siphons on opposite ends of their hollow cylindrical bodies. In the simplest cases, it seems like some species of salp can successfully move by contracting just two siphons connected by an elastic body. When thought of as a chain of timed contractions, salp propulsion is reminiscent of peristaltic pumping applied to marine locomotion. Inspired by salps, we investigate the hydrodynamics of peristaltic propulsion, focusing on the scaling relationships that determine flow rate, thrust production, and energy usage in a model system. We discuss possible actuation methods for a model peristaltic vehicle, considering both the material and geometrical requirements for such a system.

  5. CFD for hypersonic propulsion

    Science.gov (United States)

    Povinelli, Louis A.

    1991-01-01

    An overview is given of research activity on the application of computational fluid dynamics (CDF) for hypersonic propulsion systems. After the initial consideration of the highly integrated nature of air-breathing hypersonic engines and airframe, attention is directed toward computations carried out for the components of the engine. A generic inlet configuration is considered in order to demonstrate the highly three dimensional viscous flow behavior occurring within rectangular inlets. Reacting flow computations for simple jet injection as well as for more complex combustion chambers are then discussed in order to show the capability of viscous finite rate chemical reaction computer simulations. Finally, the nozzle flow fields are demonstrated, showing the existence of complex shear layers and shock structure in the exhaust plume. The general issues associated with code validation as well as the specific issue associated with the use of CFD for design are discussed. A prognosis for the success of CFD in the design of future propulsion systems is offered.

  6. Alternate Propulsion Energy Sources

    Science.gov (United States)

    1983-12-01

    ion drive solar heat collector prime power antigravity inertia cancellation drive flywheels inertia redistribution drive fusion ramjet microwave phase...antihydrogen "fuel" are then transferred to the using vehicle . When propulsive energy is desired, the antiprotons are extracted from the antihydrogen ice...environments with minimum energy input to the antihydrogen ice. The "fuel tanks" with their antihydrogen ice "fuel" will be transferred to the using vehicle

  7. Why Density Dependent Propulsion?

    Science.gov (United States)

    Robertson, Glen A.

    2011-01-01

    In 2004 Khoury and Weltman produced a density dependent cosmology theory they call the Chameleon, as at its nature, it is hidden within known physics. The Chameleon theory has implications to dark matter/energy with universe acceleration properties, which implies a new force mechanism with ties to the far and local density environment. In this paper, the Chameleon Density Model is discussed in terms of propulsion toward new propellant-less engineering methods.

  8. A robotic wheelchair trainer: design overview and a feasibility study

    Directory of Open Access Journals (Sweden)

    Marchal-Crespo Laura

    2010-08-01

    Full Text Available Abstract Background Experiencing independent mobility is important for children with a severe movement disability, but learning to drive a powered wheelchair can be labor intensive, requiring hand-over-hand assistance from a skilled therapist. Methods To improve accessibility to training, we developed a robotic wheelchair trainer that steers itself along a course marked by a line on the floor using computer vision, haptically guiding the driver's hand in appropriate steering motions using a force feedback joystick, as the driver tries to catch a mobile robot in a game of "robot tag". This paper provides a detailed design description of the computer vision and control system. In addition, we present data from a pilot study in which we used the chair to teach children without motor impairment aged 4-9 (n = 22 to drive the wheelchair in a single training session, in order to verify that the wheelchair could enable learning by the non-impaired motor system, and to establish normative values of learning rates. Results and Discussion Training with haptic guidance from the robotic wheelchair trainer improved the steering ability of children without motor impairment significantly more than training without guidance. We also report the results of a case study with one 8-year-old child with a severe motor impairment due to cerebral palsy, who replicated the single-session training protocol that the non-disabled children participated in. This child also improved steering ability after training with guidance from the joystick by an amount even greater than the children without motor impairment. Conclusions The system not only provided a safe, fun context for automating driver's training, but also enhanced motor learning by the non-impaired motor system, presumably by demonstrating through intuitive movement and force of the joystick itself exemplary control to follow the course. The case study indicates that a child with a motor system impaired by CP can

  9. Numerical Propulsion System Simulation

    Science.gov (United States)

    Naiman, Cynthia

    2006-01-01

    The NASA Glenn Research Center, in partnership with the aerospace industry, other government agencies, and academia, is leading the effort to develop an advanced multidisciplinary analysis environment for aerospace propulsion systems called the Numerical Propulsion System Simulation (NPSS). NPSS is a framework for performing analysis of complex systems. The initial development of NPSS focused on the analysis and design of airbreathing aircraft engines, but the resulting NPSS framework may be applied to any system, for example: aerospace, rockets, hypersonics, power and propulsion, fuel cells, ground based power, and even human system modeling. NPSS provides increased flexibility for the user, which reduces the total development time and cost. It is currently being extended to support the NASA Aeronautics Research Mission Directorate Fundamental Aeronautics Program and the Advanced Virtual Engine Test Cell (AVETeC). NPSS focuses on the integration of multiple disciplines such as aerodynamics, structure, and heat transfer with numerical zooming on component codes. Zooming is the coupling of analyses at various levels of detail. NPSS development includes capabilities to facilitate collaborative engineering. The NPSS will provide improved tools to develop custom components and to use capability for zooming to higher fidelity codes, coupling to multidiscipline codes, transmitting secure data, and distributing simulations across different platforms. These powerful capabilities extend NPSS from a zero-dimensional simulation tool to a multi-fidelity, multidiscipline system-level simulation tool for the full development life cycle.

  10. Propulsion for CubeSats

    Science.gov (United States)

    Lemmer, Kristina

    2017-05-01

    At present, very few CubeSats have flown in space featuring propulsion systems. Of those that have, the literature is scattered, published in a variety of formats (conference proceedings, contractor websites, technical notes, and journal articles), and often not available for public release. This paper seeks to collect the relevant publically releasable information in one location. To date, only two missions have featured propulsion systems as part of the technology demonstration. The IMPACT mission from the Aerospace Corporation launched several electrospray thrusters from Massachusetts Institute of Technology, and BricSAT-P from the United States Naval Academy had four micro-Cathode Arc Thrusters from George Washington University. Other than these two missions, propulsion on CubeSats has been used only for attitude control and reaction wheel desaturation via cold gas propulsion systems. As the desired capability of CubeSats increases, and more complex missions are planned, propulsion is required to accomplish the science and engineering objectives. This survey includes propulsion systems that have been designed specifically for the CubeSat platform and systems that fit within CubeSat constraints but were developed for other platforms. Throughout the survey, discussion of flight heritage and results of the mission are included where publicly released information and data have been made available. Major categories of propulsion systems that are in this survey are solar sails, cold gas propulsion, electric propulsion, and chemical propulsion systems. Only systems that have been tested in a laboratory or with some flight history are included.

  11. Alternative input medium development for wheelchair user with severe spinal cord injury

    Science.gov (United States)

    Ihsan, Izzat Aqmar; Tomari, Razali; Zakaria, Wan Nurshazwani Wan; Othman, Nurmiza

    2017-09-01

    Quadriplegia or tetraplegia patients have restricted four limbs as well as torso movement caused by severe spinal cord injury. Undoubtedly, these patients face difficulties when operating their powered electric wheelchair since they are unable to control the wheelchair by means of a standard joystick. Due to total loss of both sensory and motor function of the four limbs and torso, an alternative input medium for the wheelchair will be developed to assist the user in operating the wheelchair. In this framework, the direction of the wheelchair movement is determined by the user's conscious intent through a brain control interface (BCI) based on Electroencephalogram (EEG) signal. A laser range finder (LFR) is used to perceive environment information for determining a safety distance of the wheelchair's surrounding. Local path planning algorithm will be developed to provide navigation planner along with user's input to prevent collision during control operation.

  12. Heat transfer in aerospace propulsion

    Science.gov (United States)

    Simoneau, Robert J.; Hendricks, Robert C.; Gladden, Herbert J.

    1988-01-01

    Presented is an overview of heat transfer related research in support of aerospace propulsion, particularly as seen from the perspective of the NASA Lewis Research Center. Aerospace propulsion is defined to cover the full spectrum from conventional aircraft power plants through the Aerospace Plane to space propulsion. The conventional subsonic/supersonic aircraft arena, whether commercial or military, relies on the turbine engine. A key characteristic of turbine engines is that they involve fundamentally unsteady flows which must be properly treated. Space propulsion is characterized by very demanding performance requirements which frequently push systems to their limits and demand tailored designs. The hypersonic flight propulsion systems are subject to severe heat loads and the engine and airframe are truly one entity. The impact of the special demands of each of these aerospace propulsion systems on heat transfer is explored.

  13. Pilot Study of a Peer-Led Wheelchair Training Program to Improve Self-Efficacy Using a Manual Wheelchair: A Randomized Controlled Trial.

    Science.gov (United States)

    Best, Krista L; Miller, William C; Huston, Grant; Routhier, Francois; Eng, Janice J

    2016-01-01

    To evaluate the effect of a peer-led wheelchair training program on self-efficacy of manual wheelchair (MWC) use and to explore influences of the intervention on MWC skills, life-space mobility, and satisfaction with participation. Pilot randomized controlled trial. Rehabilitation center and community. Community-living MWC users (N=28; mean MWC experience, 13y; mean age, 49y; 6 [21%] women). The experimental group (n=16) received six 1.5-hour sessions of a peer-led self-efficacy-enhanced wheelchair training program (WheelSee). On the basis of individualized goals, peer trainers administered WheelSee to pairs of MWC users. The control group (n=12) received no intervention. The primary outcome--wheelchair use self-efficacy--was assessed using the Wheelchair Use Confidence Scale (WheelCon) version 3.0. Secondary outcomes included wheelchair skills capacity and performance (Wheelchair Skills Test Questionnaire version 4.1), life-space mobility (Life Space Assessment), and satisfaction with participation (Wheelchair Outcome Measure). Controlling for baseline scores, an analysis of covariance revealed that WheelSee had a large statistically significant effect on MWC use self-efficacy in community-living adult MWC users (Cohen d=1.4; P=.002) than in a control group. WheelSee also had a large statistically significant effect on MWC skills capacity (Cohen d=1.3; P=.003) and performance (Cohen d=1.0; P=.02). There were no statistically significant differences in life-space mobility or satisfaction with participation scores between the groups. A peer-led MWC training program improves wheelchair use self-efficacy in adult MWC users and had a positive influence on other wheelchair-related outcomes. WheelSee may offer a promising intervention strategy to accommodate the training needs of community-living MWC users. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  14. Modeling of Ship Propulsion Performance

    DEFF Research Database (Denmark)

    Pedersen, Benjamin Pjedsted; Larsen, Jan

    2009-01-01

    Full scale measurements of the propulsion power, ship speed, wind speed and direction, sea and air temperature, from four different loading conditions has been used to train a neural network for prediction of propulsion power. The network was able to predict the propulsion power with accuracy...... between 0.8-2.8%, which is about the same accuracy as for the measurements. The methods developed are intended to support the performance monitoring system SeaTrend® developed by FORCE Technology (FORCE (2008))....

  15. Methane Propulsion Elements for Mars

    Science.gov (United States)

    Percy, Tom; Polsgrove, Tara; Thomas, Dan

    2017-01-01

    Human exploration beyond LEO relies on a suite of propulsive elements to: (1) Launch elements into space, (2) Transport crew and cargo to and from various destinations, (3) Provide access to the surface of Mars, (4) Launch crew from the surface of Mars. Oxygen/Methane propulsion systems meet the unique requirements of Mars surface access. A common Oxygen/Methane propulsion system is being considered to reduce development costs and support a wide range of primary & alternative applications.

  16. Space Propulsion by Intermittent Combustion

    Science.gov (United States)

    1984-10-01

    principles. The AFOSR program enbraces a variety of propulsion concepts - chemical rockets, electrical ion beam or plasma propulsion, laser beam... electric ion accelerator. Of course there may be other practical types of moderate-to-high thrust propulsion engines, but the chemical rocket looks...1 pulsejet. His theoretical analysis indicated that for the best specific fuel comsumption the flight Mach number should be either <ə or >1. .he

  17. Developing product quality standards for wheelchairs used in less-resourced environments

    Directory of Open Access Journals (Sweden)

    Anand Mhatre

    2017-01-01

    Full Text Available Background: Premature failures of wheelchairs in less-resourced environments (LREs may be because of shortcomings in product regulation and quality standards. The standards published by the International Organization for Standardization (ISO specify wheelchair tests for durability, safety and performance, but their applicability to products used in the rugged conditions of LREs is unclear. Because of this, wheelchair-related guidelines published by the World Health Organization recommended developing more rigorous durability tests for wheelchairs.Objectives: This study was performed to identify the additional tests needed for LREs.Methods: First, a literature review of the development of ISO test standards, wheelchair standards testing studies and wheelchair evaluations in LREs was performed. Second, expert advice from members of the Standards Working Group of the International Society of Wheelchair Professionals (ISWP was compiled and reviewed.Results: A total of 35 articles were included in the literature review. Participation from LREs was not observed in the ISO standards development. As per wheelchair testing study evidence, wheelchair models delivered in LREs did not meet the minimum standards requirement. Multiple part failures and repairs were observed with reviewed field evaluation studies. ISWP experts noted that several testing factors responsible for premature failures with wheelchair parts are not included in the standards and accordingly provided advice for additional test development.Conclusion: The study findings indicate the need to develop a wide range of tests, with specific tests for measuring corrosion resistance of the entire wheelchair, rolling resistance of castors and rear wheels, and durability of whole wheelchair and castor assemblies.

  18. Efficacy of a powered wheelchair simulator for school aged children: A randomised controlled trial.

    OpenAIRE

    Linden, Mark A; Whyatt, Caroline; Craig, Cathy; Kerr, Claire

    2013-01-01

    Purpose: To determine the efficacy of a custom made wheelchair simulation in training children to use a powered wheelchair (PWC). Design: Randomised controlled trial employing the 4C/ID-model of learning. Twenty-eight typically developing children (13M, 15F; mean age 6 years, SD 6 months) were assessed on their operation of a PWC using a functional evaluation rating scale. Participants were randomly assigned to intervention (8x 30minute training sessions using a joystick operated wheelchair s...

  19. The Functional Classification and Field Test Performance in Wheelchair Basketball Players

    OpenAIRE

    Gil, Susana Mar?a; Yanci, Javier; Otero, Montserrat; Olasagasti, Jurgi; Badiola, Aduna; Bidaurrazaga-Letona, Iraia; Iturricastillo, Aitor; Granados, Cristina

    2015-01-01

    Wheelchair basketball players are classified in four classes based on the International Wheelchair Basketball Federation (IWBF) system of competition. Thus, the aim of the study was to ascertain if the IWBF classification, the type of injury and the wheelchair experience were related to different performance field-based tests. Thirteen basketball players undertook anthropometric measurements and performance tests (hand dynamometry, 5 m and 20 m sprints, 5 m and 20 m sprints with a ball, a T-t...

  20. Electric Propulsion Research Building (EPRB)

    Data.gov (United States)

    Federal Laboratory Consortium — The Electric Propulsion Research Building (EPRB) capability centers on its suite of vacuum chambers, which are configured to meet the unique requirements related to...

  1. Reactors for nuclear electric propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades.

  2. Electrolysis Propulsion for Spacecraft Applications

    Science.gov (United States)

    deGroot, Wim A.; Arrington, Lynn A.; McElroy, James F.; Mitlitsky, Fred; Weisberg, Andrew H.; Carter, Preston H., II; Myers, Blake; Reed, Brian D.

    1997-01-01

    Electrolysis propulsion has been recognized over the last several decades as a viable option to meet many satellite and spacecraft propulsion requirements. This technology, however, was never used for in-space missions. In the same time frame, water based fuel cells have flown in a number of missions. These systems have many components similar to electrolysis propulsion systems. Recent advances in component technology include: lightweight tankage, water vapor feed electrolysis, fuel cell technology, and thrust chamber materials for propulsion. Taken together, these developments make propulsion and/or power using electrolysis/fuel cell technology very attractive as separate or integrated systems. A water electrolysis propulsion testbed was constructed and tested in a joint NASA/Hamilton Standard/Lawrence Livermore National Laboratories program to demonstrate these technology developments for propulsion. The results from these testbed experiments using a I-N thruster are presented. A concept to integrate a propulsion system and a fuel cell system into a unitized spacecraft propulsion and power system is outlined.

  3. Laser propulsion: a review

    CSIR Research Space (South Africa)

    Michaelis, MM

    2006-07-01

    Full Text Available is that the Crookes radiometer rotates due to photon rather than gas pressure. In fact, the very first pure photon pendulum experiment was carried out by American laser propulsion enthusiasts Myrabo, Knowles, Bagford, Siebert and Harris.31 The photon pressure... is minute: the photon force on a 10-cm2 target illuminated by a 9-kW CO2 laser is found from: hence the need for an ultra-delicate pendulum equipment, as well as for a high-power laser source! In marked contrast to the Myrabo experiment...

  4. Additive Manufacturing of Aerospace Propulsion Components

    Science.gov (United States)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  5. Sport orientation and athletic identity of Greek wheelchair basketball players.

    Science.gov (United States)

    Kokaridas, Dimitrios; Perkos, Stefanos; Harbalis, Thomas; Koltsidas, Evaggelos

    2009-12-01

    The purpose of this study was to examine sport orientation and athletic identity of Greek wheelchair basketball players. The sample consisted of 50 male wheelchair basketball players all coming from different teams participating at the Greek National Championship. Thirty-three (n = 33) participants had acquired disabilities, and 17 (n = 17) participants had congenital disabilities. The years of training of the participants ranged from 1 to 22 years. All subjects completed the Sport Orientation Questionnaire, with factors of competitiveness, goal orientation, and win orientation, and the Athletic Orientation Questionnaire which assesses personal identity, social identity, exclusivity, and negative effect. The study indicated satisfactory internal consistency for the questionnaires' factors. Furthermore, players with congenital disabilities appeared more win-oriented and focused on specific goals and with stronger self-perception of their athletic role compared to players with acquired disabilities.

  6. Biometrically modulated collaborative control for an assistive wheelchair.

    Science.gov (United States)

    Urdiales, Cristina; Fernandez-Espejo, Blanca; Annicchiaricco, Roberta; Sandoval, Francisco; Caltagirone, Carlo

    2010-08-01

    To operate a wheelchair, people with severe physical disabilities may require assistance, which can be provided by robotization. However, medical experts report that an excess of assistance may lead to loss of residual skills, so that it is important to provide just the right amount of assistance. This work proposes a collaborative control system based on weighting the robot's and the user's commands by their respective efficiency to reactively obtain an emergent controller. Thus, the better the person operates, the more control he/she gains. Tests with volunteers have proven, though, that some users may require extra assistance when they become stressed. Hence, we propose a controller that can change the amount of support taking into account supplementary biometric data. In this work, we use an off-the-shelf wearable pulse oximeter. Experiments have demonstrated that volunteers could use our wheelchair in a more efficient way due to the proposed biometric modulated collaborative control.

  7. Overview on hybrid propulsion

    Science.gov (United States)

    Calabro, M.

    2011-10-01

    Aside of research works, this historical survey shows propulsion units used by students for small satellites and for gas generation, or those for the Space Ship One, even if LOx/HTPB was studied and tested in large motors for its potential very low cost; however, this combination highlights a series of technical problems without any performance advantage over the existing LOx/Kerosene family and never been operational for ETO applications. The particularity of hybrid propulsion is to use the state-of-the-art of both liquids and solids; the only show stopper is the propellant itself. The past work focused on LOx/HTPB (selected for its low cost) appears to be a dead-end (combustion problems and global low performances resulting from a high level of residuals). The solution that appears through the past experience is the addition of hydrides to a binder (HTPB or other) or to a binder and a homogeneous fuel or a mixture of both, with or without others additives; within these solutions some will not present any manufacturing problem and some may have a low cost. Nevertheless, the studies of the following phases have to demonstrate the compatibility of the potential regression rate range with a high-performance global design of a hybrid Motor and the manufacturing at a reasonable cost of a hydride giving a high level of performances.

  8. Research on Optimization, Dynamics and Stability of Stairclimbing Wheelchair

    OpenAIRE

    Shashank Shekhar Sahoo; Himank Kinkar

    2016-01-01

    Since the invention of the wheel, man has always sought to reduce effort to get things done easily. Ultimately, it has resulted in the invention of the Robot, an Engineering Marvel. Up until now, the major factor that hampers widespread usage of robots is locomotion and maneuverability. They are not fit enough to conform even to the most commonplace terrain such as stairs. To overcome this, we are proposing a stair climbing wheelchair robot that looks a lot like a normal wheelchai...

  9. Posture Detection Based on Smart Cushion for Wheelchair Users

    Directory of Open Access Journals (Sweden)

    Congcong Ma

    2017-03-01

    Full Text Available The postures of wheelchair users can reveal their sitting habit, mood, and even predict health risks such as pressure ulcers or lower back pain. Mining the hidden information of the postures can reveal their wellness and general health conditions. In this paper, a cushion-based posture recognition system is used to process pressure sensor signals for the detection of user’s posture in the wheelchair. The proposed posture detection method is composed of three main steps: data level classification for posture detection, backward selection of sensor configuration, and recognition results compared with previous literature. Five supervised classification techniques—Decision Tree (J48, Support Vector Machines (SVM, Multilayer Perceptron (MLP, Naive Bayes, and k-Nearest Neighbor (k-NN—are compared in terms of classification accuracy, precision, recall, and F-measure. Results indicate that the J48 classifier provides the highest accuracy compared to other techniques. The backward selection method was used to determine the best sensor deployment configuration of the wheelchair. Several kinds of pressure sensor deployments are compared and our new method of deployment is shown to better detect postures of the wheelchair users. Performance analysis also took into account the Body Mass Index (BMI, useful for evaluating the robustness of the method across individual physical differences. Results show that our proposed sensor deployment is effective, achieving 99.47% posture recognition accuracy. Our proposed method is very competitive for posture recognition and robust in comparison with other former research. Accurate posture detection represents a fundamental basic block to develop several applications, including fatigue estimation and activity level assessment.

  10. Sliding Mode Control for Trajectory Tracking of an Intelligent Wheelchair

    Directory of Open Access Journals (Sweden)

    Razvan SOLEA

    2009-12-01

    Full Text Available This paper deal with a robust sliding-mode trajectory tracking controller, fornonholonomic wheeled mobile robots and its experimental evaluation by theimplementation in an intelligent wheelchair (RobChair. The proposed control structureis based on two nonlinear sliding surfaces ensuring the tracking of the three outputvariables, with respect to the nonholonomic constraint. The performances of theproposed controller for the trajectory planning problem with comfort constraint areverified through the real time acceleration provided by an inertial measurement unit.

  11. A Front-Row Seat at a Wheelchair Crash Test: EP Kicks Off Its Wheelchair Transportation Safety Series with a Visit to the University of Michigan's Transportation Research Institute

    Science.gov (United States)

    Hollingsworth, Jan Carter

    2007-01-01

    The centerpiece of the University of Michigan's Transportation Research Institute (UMTRI) Sled Lab is "the impact sled," as it is called in the business. It's the business of conducting sled impact tests, perhaps better known as crash tests, on all types of wheelchairs and wheelchair seating systems as well as wheelchair tiedowns and…

  12. Vitamin D deficiency in Swiss elite wheelchair athletes.

    Science.gov (United States)

    Flueck, J L; Hartmann, K; Strupler, M; Perret, C

    2016-11-01

    This is a retrospective analysis of total serum 25-hydroxyvitamin D (25[OH]D) in Swiss elite wheelchair athletes. The aim was to investigate the occurrence of vitamin D deficiency in Swiss elite wheelchair athletes over the whole year and to detect differences between winter and summer months, and between indoor and outdoor athletes. This study was conducted in Switzerland. A total of 164 blood samples from 72 Swiss elite wheelchair athletes (mean±s.d.: age 32±13 years) were analyzed for total serum 25[OH]D. All participants were members of the national team in their discipline. The following disciplines have been included: rugby, athletics, cycling, tennis, ski alpine, curling and basketball. According to general guidelines, insufficient vitamin D status was defined between 50 and 75 nmol l-1, deficiency below 50 nmol l-1 and severe deficiency below 27.5 nmol l-1. In all, 73.2% of all samples showed an insufficiency/deficiency in vitamin D status. Total serum 25[OH]D was significantly higher during summer compared with winter months (69.5±21.4 nmol l-1 vs 51.5±21.9 nmol l-1; Pwheelchair athletes. Conclusively, we recommend supplementation with vitamin D-especially during winter-to prevent a deficiency and an impairment of performance.

  13. Performance analysis of elite men's and women's wheelchair basketball teams.

    Science.gov (United States)

    Gómez, Miguel Ángel; Pérez, Javier; Molik, Bartosz; Szyman, Robert J; Sampaio, Jaime

    2014-01-01

    The purpose of the present study was to identify which game-related statistics discriminate winning and losing teams in men's and women's elite wheelchair basketball. The sample comprised all the games played during the Beijing Paralympics 2008 and the World Wheelchair Basketball Championship 2010. The game-related statistics from the official box scores were gathered and data were analysed in 2 groups: balanced games (final score differences ≤ 12 points) and unbalanced games (final score differences >13 points). Discriminant analysis allowed identifying the successful 2-point field-goals and free-throws, the unsuccessful 3-point field-goals and free-throws, the assists and fouls received as discriminant statistics between winning and losing teams in men's balanced games. In women's games, the teams were discriminated only by the successful 2-point field-goals. Linear regression analysis showed that the quality of opposition had great effects in final point differential. The field-goals percentage and free-throws rate were the most important factors in men's games, and field-goals percentage and offensive rebounding percentage in women's games. The identified trends allow improving game understanding and helping wheelchair basketball coaches to plan accurate practice sessions and, ultimately, deciding better in competition.

  14. Soft, conformal bioelectronics for a wireless human-wheelchair interface.

    Science.gov (United States)

    Mishra, Saswat; Norton, James J S; Lee, Yongkuk; Lee, Dong Sup; Agee, Nicolas; Chen, Yanfei; Chun, Youngjae; Yeo, Woon-Hong

    2017-05-15

    There are more than 3 million people in the world whose mobility relies on wheelchairs. Recent advancement on engineering technology enables more intuitive, easy-to-use rehabilitation systems. A human-machine interface that uses non-invasive, electrophysiological signals can allow a systematic interaction between human and devices; for example, eye movement-based wheelchair control. However, the existing machine-interface platforms are obtrusive, uncomfortable, and often cause skin irritations as they require a metal electrode affixed to the skin with a gel and acrylic pad. Here, we introduce a bioelectronic system that makes dry, conformal contact to the skin. The mechanically comfortable sensor records high-fidelity electrooculograms, comparable to the conventional gel electrode. Quantitative signal analysis and infrared thermographs show the advantages of the soft biosensor for an ergonomic human-machine interface. A classification algorithm with an optimized set of features shows the accuracy of 94% with five eye movements. A Bluetooth-enabled system incorporating the soft bioelectronics demonstrates a precise, hands-free control of a robotic wheelchair via electrooculograms. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Wheelchair users, access and exclusion in South African higher education.

    Science.gov (United States)

    Chiwandire, Desire; Vincent, Louise

    2017-01-01

    South Africa's Constitution guarantees everyone, including persons with disabilities, the right to education. A variety of laws are in place obliging higher education institutions to provide appropriate physical access to education sites for all. In practice, however, many buildings remain inaccessible to people with physical disabilities. To describe what measures South African universities are taking to make their built environments more accessible to students with diverse types of disabilities, and to assess the adequacy of such measures. We conducted semi-structured in-depth face-to-face interviews with disability unit staff members (DUSMs) based at 10 different public universities in South Africa. Challenges with promoting higher education accessibility for wheelchair users include the preservation and heritage justification for failing to modify older buildings, ad hoc approaches to creating accessible environments and failure to address access to toilets, libraries and transport facilities for wheelchair users. South African universities are still not places where all students are equally able to integrate socially. DUSMs know what ought to be done to make campuses more accessible and welcoming to students with disabilities and should be empowered to play a leading role in sensitising non-disabled members of universities, to create greater awareness of, and appreciation for, the multiple ways in which wheelchair user students continue to be excluded from full participation in university life. South African universities need to adopt a systemic approach to inclusion, which fosters an understanding of inclusion as a fundamental right rather than as a luxury.

  16. Development of Android Based Powered Intelligent Wheelchair for Quadriplegic Persons

    Science.gov (United States)

    Gupta, Ashutosh; Ghosh, Tathagata; Kumar, Pradeep; Bhawna, Shruthi. S.

    2017-08-01

    Several surveys give us the view that both children and adults benefit substantially from access towards independent mobility. With the inventions of technology, no individuals are satisfied with traditional manual operated machines. To accommodate population, researchers are using technology, originally developed for mobile robots to create ‘intelligent wheelchairs’. It’s a major challenge for quadriplegic persons as they really find it difficult to manipulate powered wheelchair during the activities of their daily living. As the Smartphone era has evolved with innovative android based applications, engineers are improving and trying to make such machines simple and cheap to the next level. In this paper, we present a development of android based powered intelligent wheelchair to assist the quadriplegic person by making them self sufficient in controlling the wheelchair. The wheels of the chair can be controlled by the voice or gesture movement or by touching the screen of the android app by the challenged persons. The system uses the Bluetooth communication to interface the microcontroller and the inbuilt sensors in the android Smartphone. According to the commands received from android phone, the kinematics of the wheels are controlled.

  17. Participatory design and validation of mobility enhancement robotic wheelchair.

    Science.gov (United States)

    Daveler, Brandon; Salatin, Benjamin; Grindle, Garrett G; Candiotti, Jorge; Wang, Hongwu; Cooper, Rory A

    2015-01-01

    The design of the mobility enhancement robotic wheelchair (MEBot) was based on input from electric powered wheelchair (EPW) users regarding the conditions they encounter when driving in both indoor and outdoor environments that may affect their safety and result in them becoming immobilized, tipping over, or falling out of their wheelchair. Phase I involved conducting a participatory design study to understand the conditions and barriers EPW users found to be difficult to drive in/over. Phase II consisted of creating a computer-aided design (CAD) prototype EPW to provide indoor and outdoor mobility that addressed these conditions with advanced applications. Phase III involved demonstrating the advanced applications and gathering feedback from end users about the likelihood they would use the advanced applications. The CAD prototype incorporated advanced applications, including self-leveling, curb climbing, and traction control, that addressed the challenging conditions and barriers discussed with EPW users (n = 31) during the participatory design study. Feedback of the CAD design and applications in phase III from end users (n = 12) showed a majority would use self-leveling (83%), traction control (83%), and curb climbing (75%). The overall design of MEBot received positive feedback from EPW users. However, these opinions will need to be reevaluated through user trials as the design advances.

  18. In-Space Propulsion (346620) Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Technologies include, but are not limited to, electric and advanced chemical propulsion, propellantless propulsion such as aerocapture and solar sails, sample return...

  19. Using fuzzy logic to mitigate the effect of multiple-sclerosis tremors on a wheelchair joystick controller

    NARCIS (Netherlands)

    Antoniou, Grigoris; Corbett, Dan; van der Zwaag, B.J.; Slaney, John

    1998-01-01

    We have designed a fuzzy logic wheelchair controller to minimise the effect of Multiple Sclerosis hand tremors on a wheelchair joystick controller. The aim is to give people with Multiple Sclerosis better control of an electric wheelchair by removing tremors from the joystick signal. This has been

  20. 14 CFR 382.129 - What other requirements apply when passengers' wheelchairs, other mobility aids, and other...

    Science.gov (United States)

    2010-01-01

    ... passengers' wheelchairs, other mobility aids, and other assistive devices must be disassembled for stowage... Stowage of Wheelchairs, Other Mobility Aids, and Other Assistive Devices § 382.129 What other requirements apply when passengers' wheelchairs, other mobility aids, and other assistive devices must be...

  1. Can a 15m-overground wheelchair sprint be used to assess wheelchair-specific anaerobic work capacity?

    Science.gov (United States)

    van der Scheer, Jan W; de Groot, Sonja; Vegter, Riemer J K; Veeger, Dirkjan H E J; van der Woude, Lucas H V

    2014-04-01

    To evaluate whether outcomes based on stopwatch time and power output (PO) over a 15m-overground wheelchair sprint test can be used to assess wheelchair-specific anaerobic work capacity, by studying their relationship with outcomes on a Wingate-based 30s-wheelchair ergometer sprint (WAnT). Able-bodied persons (N=19, 10 men, aged 18-26 y) performed a 15m overground sprint test in an instrumented wheelchair and a WAnT. 15m-outcomes were based on stopwatch time (time and mean velocity over 15m) and on PO (primary outcome: highest mean unilateral PO over successive 5s-intervals (P5-15m)). WAnT-outcomes were mean unilateral PO over 30s and the highest mean unilateral PO over successive 5s-intervals. Correlation coefficients (Pearson's r) and coefficients of determination (R(2)) were calculated between 15m-sprint outcomes and WAnT-outcomes. Time over 15m (7.2s (± 1.0)) was weakly related to WAnT-outcomes (r=-0.61 and -0.60, R(2)=0.38 and 0.36, pwheel can be implemented in rehabilitation practice and research settings when WAnT equipment is not available, although care is needed when interpreting P5-15m as an outcome of anaerobic work capacity given that it seems more skill-dependent than the WAnT. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  2. Hypersonic propulsion research

    Science.gov (United States)

    Northam, G. Burton

    1990-01-01

    The development of technology for the modular airframe integrated scramjet has been the focus of hypersonic propulsion research for several years. An part of this research, a variety of inlet concepts have been explored and characterized. The emphasis of the inlet program has been the development of the short (light weight), fixed geometry, side wall compression inlets that operate efficiently over a wide Mach number range. As hypersonic combustion tunnels were developed, programs to study the parameters controlling fuel mixing and combustion with single and multiple strut models were conducted using direct connect test techniques. These various tests supported the design of subscale engine test hardware that integrated inlet and combustor technology and allowed the study of the effect of heat release on thrust and combustor/inlet interaction. A number of subscale engine tests have shown predicted performance levels at Mach 4 and 7 simulated flight conditions. A few of the highlights from this research program are summarized.

  3. The Relationship of Skills of Elite Wheelchair Basketball Competitors to the International Functional Classification System.

    Science.gov (United States)

    Brasile, Frank M.; Hedrick, Bradley N.

    1996-01-01

    This study investigated the relationship between skill performance levels of 31 elite male wheelchair basketball players and their international player classification level. Analysis of a skills test of each athlete indicated that there is a need to reevaluate the functional classification system used in wheelchair basketball competitions. (SM)

  4. Opportunities for measuring wheelchair kinematics in match settings; reliability of a three inertial sensor configuration.

    Science.gov (United States)

    van der Slikke, R M A; Berger, M A M; Bregman, D J J; Lagerberg, A H; Veeger, H E J

    2015-09-18

    Knowledge of wheelchair kinematics during a match is prerequisite for performance improvement in wheelchair basketball. Unfortunately, no measurement system providing key kinematic outcomes proved to be reliable in competition. In this study, the reliability of estimated wheelchair kinematics based on a three inertial measurement unit (IMU) configuration was assessed in wheelchair basketball match-like conditions. Twenty participants performed a series of tests reflecting different motion aspects of wheelchair basketball. During the tests wheelchair kinematics were simultaneously measured using IMUs on wheels and frame, and a 24-camera optical motion analysis system serving as gold standard. Results showed only small deviations of the IMU method compared to the gold standard, once a newly developed skid correction algorithm was applied. Calculated Root Mean Square Errors (RMSE) showed good estimates for frame displacement (RMSE≤0.05 m) and speed (RMSE≤0.1m/s), except for three truly vigorous tests. Estimates of frame rotation in the horizontal plane (RMSE0.90), rotational speed (ICC>0.99) and IRC (ICC> 0.90) showed high correlations between IMU data and gold standard. IMU based estimation of wheelchair kinematics provided reliable results, except for brief moments of wheel skidding in truly vigorous tests. The IMU method is believed to enable prospective research in wheelchair basketball match conditions and contribute to individual support of athletes in everyday sports practice. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Demographic Profile and Athletic Identity of Traumatic Spinal Cord Injured Wheelchair Basketball Athletes in Greece

    Science.gov (United States)

    Vasiliadis, Angelo; Evaggelinou, Christina; Avourdiadou, Sevastia; Grekinis, Petros

    2010-01-01

    An epidemiological study conducted across the country of Greece was conducted in order to determine the profile and the athletic identity of spinal cord injured (SCI) wheelchair basketball athletes who participated to the 13th Greek Wheelchair Basketball Championship and Cup. The Disability Sport Participation questionnaire was used for data…

  6. Validity and reliability of tests determining performance-related components of wheelchair basketball

    NARCIS (Netherlands)

    De Groot, Sonja; Balvers, Inge J. M.; Kouwenhoven, Sanne M.; Janssen, Thomas W. J.

    2012-01-01

    The purpose of this study was to investigate the reliability and validity of wheelchair basketball field tests. Nineteen wheelchair basketball players performed 10 test items twice to determine the reliability. The validity of the tests was assessed by relating the scores to the players'

  7. Influence of Glove Type on Mobility Performance for Wheelchair Rugby Players

    NARCIS (Netherlands)

    Mason, Barry S.; van der Woude, L. H. V.; Goosey-Tolfrey, V. L.

    Objective: The purpose of this study was to determine the effectiveness of different glove types on mobility performance in a series of field tests specific to wheelchair rugby. Design: Ten international wheelchair rugby players performed three drills in each glove condition: (i) players' current

  8. Psychosocial impact of wheelchair usage on individuals with mobility disability in Ibadan, Nigeria.

    Science.gov (United States)

    Hamzat, T K; Olaleye, O A; Agbomeji, O T

    2015-03-01

    Wheelchairs provide individuals with mobility impairments opportunity for independent living within their environment. However, using this device may have psychosocial impacts with consequent influence on the quality of life of the users. The psychosocial impact of wheelchair usage among individuals with mobility disability in a Nigerian community was investigated. The study is a descriptive cross-sectional survey. People who have been independent users of wheelchair for a minimum of six months prior to the study were recruited from centres for people with disabilities in Ibadan, Nigeria into the study. A profile of their use of the device was documented and the psychosocial impact of wheelchair was assessed using the Psychosocial Impact ofAssistive Devices Scale. Data were analysed using descriptive and inferential statistics at p = 0.05. Sixty consenting individuals with mobility disability participated in this study. Their mean age was 38.7 +/- 14.1 years. Majority (90%) were manual wheelchair users and two-thirds (63.3%) had been using the wheelchair for psychosocial impact of wheelchair usage between male and female users. The psychosocial impact of wheelchair was similar between male and female users. However, the impact was higher on the self-esteem of male than female users and lower on their competence than that of their female counterparts. This may be due to stigmatization or a culturally-related unwillingness of men in our environment to be dependent on others.

  9. SpinSafe: An unsupervised smartphone-based wheelchair path monitoring system

    NARCIS (Netherlands)

    Seraj, Fatjon; Havinga, Paul J.M.; Meratnia, Nirvana

    2016-01-01

    Movement and social life of wheelchair users are constrained by their disability and suitability of paths they can move on. Modern electric wheelchairs offer them assisted drive, making their movement easier and longer. They, however, do not prevent accidents, injuries, and inconveniences caused by

  10. Development of a wheelchair mobility skills test for children and adolescents: combining evidence with clinical expertise.

    NARCIS (Netherlands)

    Sol, M.E.; Vershuren, O.; Groot, L. de; Groot, J.F. de

    2017-01-01

    Background: Wheelchair mobility skills (WMS) training is regarded by children using a manual wheelchair and their parents as an important factor to improve participation and daily physical activity. Currently, there is no outcome measure available for the evaluation of WMS in children. Several

  11. The Effect of Wheel Size on Mobility Performance in Wheelchair Athletes

    NARCIS (Netherlands)

    Mason, B.; van der Woude, L.; Lenton, J. P.; Goosey-Tolfrey, V.

    2012-01-01

    The purpose of the current study was to investigate the effects of different wheel sizes, with fixed gear ratios, on maximal effort mobility performance in wheelchair athletes. 13 highly trained wheelchair basketball players, grouped by classification level, performed a battery of 3 field tests in

  12. Effect of visual perception, visual function, cognition, and personality on power wheelchair use in adults.

    Science.gov (United States)

    Massengale, Samantha; Folden, Donna; McConnell, Pima; Stratton, Laurie; Whitehead, Victoria

    2005-01-01

    The purpose of this study was to determine to what extent visual perception, visual function, cognition, and personality traits affect power wheelchair use in adults. It also proposes to establish baseline information to help clinicians determine or predict power wheelchair driving performance and to develop service plans to address those driving skills that need improvement or compensation. Sixty-two adult power wheelchair users were recruited. Standardized instruments were used to evaluate visual perceptual skills, visual function, cognitive skills, and personality traits. The results of these evaluations were then correlated with participants' scores on a power wheelchair performance test. Strong correlations were found between power wheelchair driving performance and visual perception (p = .000), ocular motor function (p = .000 and p < or = .001), stereodepth perception (p < or = .001), and alertness to the environment (p < or = .001). No significant correlations were found between personality traits and power wheelchair driving performance. These results indicate that good visual perceptual skills, visual function, and various aspects of cognition are necessary for proficient power wheelchair use. These data will assist clinicians in identifying significant factors to consider when evaluating and training clients for power wheelchair use.

  13. Effect of Wheelchair Frame Material on Users’ Mechanical Work and Transmitted Vibration

    Directory of Open Access Journals (Sweden)

    Félix Chénier

    2014-01-01

    similar to aluminium wheelchairs. A negative correlation between VT and WN-WPM was found, which means that reducing VT may be at the expense of increasing WN-WPM. Based on our results, use of carbon in wheelchair construction seems promising to reduce VT without increasing WN-WPM.

  14. Validity and reliability of tests determining performance-related components of wheelchair basketball

    NARCIS (Netherlands)

    de Groot, Sonja; Balvers, Inge J.M.; Kouwenhoven, Sanne M.; Janssen, Thomas W.J.

    The purpose of this study was to investigate the reliability and validity of wheelchair basketball field tests. Nineteen wheelchair basketball players performed 10 test items twice to determine the reliability. The validity of the tests was assessed by relating the scores to the players'

  15. Designing movement-based play with young people using powered wheelchairs

    DEFF Research Database (Denmark)

    Gerling, Kathrin M; Hicks, Kieran C; Kalyn, Michael R

    2016-01-01

    Young people using powered wheelchairs have limited access to engaging leisure activities. We address this issue through a two-stage project; 1) the participatory development of a set of wheelchair-controlled, movement-based games (with 9 participants at a school that provides education for young...

  16. The Effects of Rear-Wheel Camber on Maximal Effort Mobility Performance in Wheelchair Athletes

    NARCIS (Netherlands)

    Mason, B.; van der Woude, L.; Tolfrey, K.; Goosey-Tolfrey, V.

    This study examined the effect of rear-wheel camber on maximal effort wheelchair mobility performance. 14 highly trained wheelchair court sport athletes performed a battery of field tests in 4 standardised camber settings (15°, 18°, 20°, 24°) with performance analysed using a velocometer. 20 m

  17. A comparison of wrist isokinetic muscle strength in wheelchair table tennis and wheelchair basketball players

    Science.gov (United States)

    Akınoğlu, Bihter; Kocahan, Tuğba; Yıldırım, Necmiye Ün; Soylu, Çağlar; Apur, Ufuk; Hasanoğlu, Adnan

    2017-01-01

    Aim: The aim of this study was to compare isokinetic muscle strength of wrist flexor and extensor muscles in paralympic athletes. Methods: This study was carried out with the participation of 9 (4 females and 5 males) wheelchair (WC) table tennis players aged 24+3 and 8 male WC basketball players aged 26+3, met the criteria and voluntarly participate in the study. Body weight, height, body mass index and dominant extremity of the study subjects were recorded. İsokinetic measurement were performed with Isomed 2000® device. İsokinetic testing protocol; before the test all players performed the wrist flexion and extension isokinetic test with the 5 repeating at 90º/sec as a warm-up and comprehending the test. Then, wrist flexion and extension concentric-concentric strength measurements were performed with the 5 repeating at 60º/sec and with the 15 repeating at 240º/sec with the angle between 50 degrees of wrist flexion and 60 degrees of wrist extension and peak torque, peak torque/kg values and flexion/extension ratios were recorded. Mann-Whitney U test was used to compare isokinetic muscle strength quantitative variables in athletes. Findings: Isokinetic muscle strength of wrist flexors and extensors was higher in both sides in WC table tennis players with 60º/sec speed (p0,05). Wrist flexion/extension peak torque ratios were similar in both groups. When examining the athletes flexion/extension ratios, wrist extensor muscles were weaker than flexor muscles and flexor muscles were average twice stronger than extensor muscles in both sports (Table1). Table 1. Comparison of wrist flexion and extension isokinetic muscle strength, peak torque/kg and agonist/antagonist ratio of wc basketball and wc table tennis players Wheelchair table tennis(N=9)X±SD Wheelchair basketball(N=9)X±SD p* Flexion 60°/sec Dominant side PT(Nm) 23.41±11.13 8.87±1.65 0.001 PT/Kg (Nm/Kg) 0.39±0.13 0.42±0.10 0.499 Non-dominant side PT(Nm) 20.26±9.26 8.26±3.11 0.001 PT/Kg (Nm/Kg) 0

  18. A five-wheel wheelchair with an active-caster drive system.

    Science.gov (United States)

    Munakata, Yu; Tanaka, Aki; Wada, Masayoshi

    2013-06-01

    A novel wheelchair system with an active-caster drive mechanism is presented in this paper. A manual (hand propelled) wheelchair with an external single-wheel drive system forms a five-wheel configuration. The active-caster mechanism is applied to a drive system to motorize a manual wheelchair. Two electric motors which drive a wheel axis and a steering axis of a drive wheel independently are equipped on the active-caster. A coordinated control of the two motors enables the velocity vector on the steering shaft to direct in an arbitrary direction with an arbitrary magnitude. The generated velocity vector allows a wheelchair to go straight and/or rotate completely in a same way as a standard electric wheelchair. Namely 2DOF of the wheelchair can be controlled independently by a single drive wheel without any constraint, such as the orientation of the drive wheel which is well known as a non-holonomic constraint. In addition to the 2DOF mobility, the proposed system enables wheelchair users to change drive modes, a rear drive and a front drive. The drive wheel on the back side of the wheelchair is vertically actuated by a linear motor to change the height of the drive wheel that can vary load distribution and the number of wheels contacting to the ground. The five-wheel-contact makes the wheelchair to move as the normal mode in which the center of rotation is located at the midpoint of the main wheels. Depressing the drive wheel results in lost contacts of the main wheels from the ground in which the center of rotation is jumped at the midpoint of the front wheels, namely it performs as a front drive wheelchair. In this paper, kinematic models of the wheelchair and that with an active-caster drive system are analyzed and a control method by using a 2DOF joystick is derived. Based on the kinematic model, a prototype mechanism of the active-caster is designed and mounted on a manual wheelchair to realize the five-wheel wheelchair. In the experiments, the independent 2

  19. Preliminary inter-rater reliability of the wheelchair components questionnaire for condition.

    Science.gov (United States)

    Rispin, Karen; DiFrancesco, John; Raymond, Lawrence A; Riseling, Kristopher; Wee, Joy

    2017-07-07

    The Wheelchair Components Questionnaire for Condition (WCQ-C) enables the collection of data on wheelchair maintenance condition and durability in resource-limited environments. It can be used in large studies to indicate typical patterns of wear at a location, or for a type of wheelchair. It can also be used in clinical settings as an evidence based indication that a wheelchair may need repair or replacement. This type of data can enable effective use of limited funds by wheelchair providers, manufacturers and users. The goal of this study was to investigate the inter-rater reliability of the WCQ-C. Two therapists from North America who have worked extensively in low-resource areas used the WCQ-C to independently evaluate 46 wheelchairs at a primary school for children with disabilities in Kenya. Mean scores of ratings for each wheelchair by the two raters were used to calculate a two-way random interclass correlation coefficient. A value of 0.82 with a 95% confidence interval of 0.67-0.89 indicated good preliminary reliability. Preliminary results indicate that the WCQ-C is a reliable method of assessment. Additional studies are needed with larger and more diverse groups of raters. Because WCQ-C findings are specific to wheelchair wear and maintenance at each location, studies at other locations are also needed. Implications for rehabilitation The importance of inter-rater reliability testing in confirming the reliability of an assessment tool such as the WCQ-C. The use of the WCQ-C to monitor wheelchair condition in low-resource settings and other field settings. If used at regular interval can produce data that can be used to describe typical changes over time at each individual setting. This could enable proactive planning at that setting to avoid typical breakdowns and the injuries or clinical complications that could result. The use of the WCQ-C to monitor the condition of groups of wheelchairs of the same type. It can describe typical patterns of wear and

  20. Propulsion Options For Interstellar Exploration

    Science.gov (United States)

    Johnson, Les; Leifer, Stephanie

    2000-01-01

    NASA is considering missions to explore near-interstellar space (40 - 250 Astronomical Units) early in the next decade as the first step toward a vigorous interstellar exploration program. A key enabling technology for such an ambitious science and exploration effort is a propulsion system capable of providing fast trip times, yet which has low enough mass to allow for the use of inexpensive launch vehicles. Advanced propulsion technologies that might support the First interstellar precursor mission by the end of the first decade of the new millennium include solar sails and nuclear electric propulsion. Solar sails and electric propulsion are two technology areas that may hold promise for the next generation of interstellar precursor missions as well - perhaps a thousand astronomical units traveled in a professional lifetime. Future missions to far beyond the Heliosphere will require the development of propulsion technologies that are only at the conceptual stage today. For years, the scientific community has been interested in solar sail and electric propulsion technologies to support robotic exploration of the solar system. Progress in thin-film materials fabrication and handling, and advancement in technologies that may enable the deployment of large sails in space are only now maturing to the point where ambitious interstellar precursor missions using sails can be considered. Xenon ion propulsion is now being demonstrated for planetary exploration by the Deep Space 1 mission. The primary issues for the adaptation of electric propulsion to interstellar precursor applications include the development of low specific mass nuclear power systems, engine lifetime, and high power operation. Recent studies of interstellar precursor mission scenarios that use these propulsion systems will be described, and the range of application of each technology will be explored.

  1. Effectiveness of social behaviors for autonomous wheelchair robot to support elderly people in Japan.

    Directory of Open Access Journals (Sweden)

    Masahiro Shiomi

    Full Text Available We developed a wheelchair robot to support the movement of elderly people and specifically implemented two functions to enhance their intention to use it: speaking behavior to convey place/location related information and speed adjustment based on individual preferences. Our study examines how the evaluations of our wheelchair robot differ when compared with human caregivers and a conventional autonomous wheelchair without the two proposed functions in a moving support context. 28 senior citizens participated in the experiment to evaluate three different conditions. Our measurements consisted of questionnaire items and the coding of free-style interview results. Our experimental results revealed that elderly people evaluated our wheelchair robot higher than the wheelchair without the two functions and the human caregivers for some items.

  2. The power of power wheelchairs: Mobility choices of community-dwelling, older adults

    Science.gov (United States)

    Mortenson, WB; Hammell, KW; Luts, A; Soles, C; Miller, WC

    2015-01-01

    Background Power wheelchairs are purported to have a positive effect on health, occupation, and quality of life. However, there is limited knowledge about what factors shape power wheelchair use decisions. Aims/Objectives A study was undertaken to understand the mobility choices of community-dwelling, power wheelchair users. Methods A series of semi-structured qualitative interviews was conducted with 13 older adult power wheelchair users. Participants were interviewed at enrollment and four months later. Data analysis was informed by Bourdieu’s theoretical constructs of habitus, capital, and field. Results Three main styles of power wheelchair use were identified: reluctant use, strategic use and essential use, and each type is illustrated using an aggregate case study. Conclusion/Significance These findings highlight the need to alter the power relationship that exists between prescribers and device users and to effect policy changes that enable people with physical impairments to make as wide a range of mobility choices as possible. PMID:26027749

  3. Towards a new modality-independent interface for a robotic wheelchair.

    Science.gov (United States)

    Bastos-Filho, Teodiano Freire; Cheein, Fernando Auat; Müller, Sandra Mara Torres; Celeste, Wanderley Cardoso; de la Cruz, Celso; Cavalieri, Daniel Cruz; Sarcinelli-Filho, Mário; Amaral, Paulo Faria Santos; Perez, Elisa; Soria, Carlos Miguel; Carelli, Ricardo

    2014-05-01

    This work presents the development of a robotic wheelchair that can be commanded by users in a supervised way or by a fully automatic unsupervised navigation system. It provides flexibility to choose different modalities to command the wheelchair, in addition to be suitable for people with different levels of disabilities. Users can command the wheelchair based on their eye blinks, eye movements, head movements, by sip-and-puff and through brain signals. The wheelchair can also operate like an auto-guided vehicle, following metallic tapes, or in an autonomous way. The system is provided with an easy to use and flexible graphical user interface onboard a personal digital assistant, which is used to allow users to choose commands to be sent to the robotic wheelchair. Several experiments were carried out with people with disabilities, and the results validate the developed system as an assistive tool for people with distinct levels of disability.

  4. The power of power wheelchairs: Mobility choices of community-dwelling, older adults.

    Science.gov (United States)

    Mortenson, William Bennett; Hammell, Karen W; Luts, Anneli; Soles, Chelsea; Miller, William C

    2015-01-01

    Power wheelchairs are purported to have a positive effect on health, occupation, and quality of life. However, there is limited knowledge about what factors shape power wheelchair use decisions. A study was undertaken to understand the mobility choices of community-dwelling, power wheelchair users. A series of semi-structured qualitative interviews was conducted with 13 older adult power wheelchair users. Participants were interviewed at enrollment and four months later. Data analysis was informed by Bourdieu's theoretical constructs of habitus, capital, and field. Three main styles of power wheelchair use were identified: reluctant use, strategic use, and essential use, and each type is illustrated using an aggregate case study. These findings highlight the need to alter the power relationship that exists between prescribers and device users and to effect policy changes that enable people with physical impairments to make as wide a range of mobility choices as possible.

  5. Effectiveness of social behaviors for autonomous wheelchair robot to support elderly people in Japan.

    Science.gov (United States)

    Shiomi, Masahiro; Iio, Takamasa; Kamei, Koji; Sharma, Chandraprakash; Hagita, Norihiro

    2015-01-01

    We developed a wheelchair robot to support the movement of elderly people and specifically implemented two functions to enhance their intention to use it: speaking behavior to convey place/location related information and speed adjustment based on individual preferences. Our study examines how the evaluations of our wheelchair robot differ when compared with human caregivers and a conventional autonomous wheelchair without the two proposed functions in a moving support context. 28 senior citizens participated in the experiment to evaluate three different conditions. Our measurements consisted of questionnaire items and the coding of free-style interview results. Our experimental results revealed that elderly people evaluated our wheelchair robot higher than the wheelchair without the two functions and the human caregivers for some items.

  6. Explosive strength training improves speed and agility in wheelchair basketball athletes

    Directory of Open Access Journals (Sweden)

    Tarik Ozmen

    2014-04-01

    Full Text Available INTRODUCTION: Wheelchair basketball is a paralympic sport characterized by intermittent high-intensity activities that require explosive strength and speed. OBJECTIVE: To investigate the effect of explosive strength training on speed and agility performance in wheelchair basketball players. METHODS: Ten male wheelchair basketball players (Mage=31±4 yrs were divided into two groups [i.e. explosive strength training (ES; control (CN] based on International Wheelchair Basketball Federation (IWBF classification scores. The ES group underwent 6-weeks of training, twice weekly, at 50% 1RM, 10-12 repetitions and 3-4 sets in addition to routine training. Effects of training were measured by the 20 m sprint test and Illinois agility test. RESULTS: The ES group, showed significantly higher increases in speed and agility performance (p ≤ .05. CONCLUSION: A short-duration (i.e. 6-week explosive strength training programme in wheelchair basketball athletes results in significant improvements in sprint and agility performance.

  7. NASA's Nuclear Thermal Propulsion Project

    Science.gov (United States)

    Houts, Michael G.; Mitchell, Doyce P.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Clement, Steven; Borowski, Stanley K.; hide

    2015-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation NTP system could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of a first generation NTP in the development of advanced nuclear propulsion systems could be analogous to the role of the DC- 3 in the development of advanced aviation. Progress made under the NTP project could also help enable high performance fission power systems and Nuclear Electric Propulsion (NEP).

  8. Comparison of Aerobic Performance Testing Protocols in Elite Male Wheelchair Basketball Players

    Directory of Open Access Journals (Sweden)

    Molik Bartosz

    2017-12-01

    Full Text Available In wheelchair sports, aerobic performance is commonly assessed with the use of an arm crank ergometer (ACE, a wheelchair ergometer (WCE or a wheelchair treadmill (WCT. There are different protocols to identify peak oxygen uptake in wheelchair sports; however, only a few protocols have been applied to evaluate these conditions in wheelchair basketball players. The purpose of this study was to compare physiological responses during maximal exercise testing with the use of ACE and WCT in wheelchair basketball players. Twelve elite male wheelchair basketball players participated in this study. The research was performed during a training camp of the Polish National Wheelchair Basketball Team. The study participants were divided into two functional categories: A (players with class 1.0 - 2.5 and B (players with class 3.0 - 4.5. Two main maximal exercise tests, i.e. wheelchair treadmill stress test (WCT test and arm crank ergometer stress test (ACE test were used to evaluate aerobic performance of the players. There were no statistically significant differences in aerobic tests between the players from both groups. The comparison of results achieved in two aerobic tests performed on WCT and ACE did not reveal any significant differences between the analyzed variables (peak heart rate (HRpeak, peak oxygen uptake (VO2peak, minute ventilation (VE, anaerobic threshold (AT, lactate concentration (LApeak, and a drop in lactate concentration (%LA. Strong correlations between results achieved in WCT and ACE tests were found for VO2peak, VE and LApeak. The main conclusion of the study is that both WCT and ACE tests may be useful when determining aerobic capacity of wheelchair basketball players. Moreover, both protocols can be used by athletes regardless of their functional capabilities and types of impairment.

  9. Comparison of Aerobic Performance Testing Protocols in Elite Male Wheelchair Basketball Players.

    Science.gov (United States)

    Molik, Bartosz; Kosmol, Andrzej; Morgulec-Adamowicz, Natalia; Lencse-Mucha, Judit; Mróz, Anna; Gryko, Karol; Marszałek, Jolanta

    2017-12-01

    In wheelchair sports, aerobic performance is commonly assessed with the use of an arm crank ergometer (ACE), a wheelchair ergometer (WCE) or a wheelchair treadmill (WCT). There are different protocols to identify peak oxygen uptake in wheelchair sports; however, only a few protocols have been applied to evaluate these conditions in wheelchair basketball players. The purpose of this study was to compare physiological responses during maximal exercise testing with the use of ACE and WCT in wheelchair basketball players. Twelve elite male wheelchair basketball players participated in this study. The research was performed during a training camp of the Polish National Wheelchair Basketball Team. The study participants were divided into two functional categories: A (players with class 1.0 - 2.5) and B (players with class 3.0 - 4.5). Two main maximal exercise tests, i.e. wheelchair treadmill stress test (WCT test) and arm crank ergometer stress test (ACE test) were used to evaluate aerobic performance of the players. There were no statistically significant differences in aerobic tests between the players from both groups. The comparison of results achieved in two aerobic tests performed on WCT and ACE did not reveal any significant differences between the analyzed variables (peak heart rate (HRpeak), peak oxygen uptake (VO2peak), minute ventilation (VE), anaerobic threshold (AT), lactate concentration (LApeak), and a drop in lactate concentration (%LA)). Strong correlations between results achieved in WCT and ACE tests were found for VO2peak, VE and LApeak. The main conclusion of the study is that both WCT and ACE tests may be useful when determining aerobic capacity of wheelchair basketball players. Moreover, both protocols can be used by athletes regardless of their functional capabilities and types of impairment.

  10. Wheelchair service provision education and training in low and lower middle income countries: a scoping review.

    Science.gov (United States)

    McSweeney, Elizabeth; Gowran, Rosemary Joan

    2017-11-01

    Improving access to education and training for those providing wheelchair and seating assistive technology to meet personal posture and mobility requirements, as a basic human right, is a priority. This review considers education and training available to personnel within low and lower middle income countries (LLMIC), to ascertain where gaps in knowledge exist and identify human resource education priorities. A scoping review, mapping out existing scientific and grey literature within the field between 1993 and 2017 was conducted. The search strategy included use of online databases, manual analogue searches and key stakeholder informant advice. A content analysis process was applied to organize the literature retrieved and extract key themes. Education and training in LLMIC appears ad hoc and limited, however, there is growing recognition as to its importance, notably by the World Health Organization and nongovernmental organizations, delivering education initiatives to a number of countries, along with the development of a credentialing test. Inconsistency exists regarding personnel responsible for wheelchair provision, with no specific professional clearly recognized to oversee the system within many LLMIC. Education and training is required for all stakeholders involved in wheelchair provision. Advocating for programme development to enhance personnel skills, build capacity and ensure best practice is a priority. Pilot sites, delivering and credentialing appropriate wheelchair provision education and training within context should be considered. Measuring outcomes and transferable skills should be part of education programme delivery structures. Considering a new discipline responsible for oversight of wheelchair provision should be investigated. Implications for rehabilitation Education and training is an essential step in the wheelchair provision process in the bid to obtain an appropriate wheelchair via appropriate provision services. However, it is more

  11. Comparison of Aerobic Performance Testing Protocols in Elite Male Wheelchair Basketball Players

    Science.gov (United States)

    Molik, Bartosz; Kosmol, Andrzej; Morgulec-Adamowicz, Natalia; Lencse-Mucha, Judit; Mróz, Anna; Gryko, Karol

    2017-01-01

    Abstract In wheelchair sports, aerobic performance is commonly assessed with the use of an arm crank ergometer (ACE), a wheelchair ergometer (WCE) or a wheelchair treadmill (WCT). There are different protocols to identify peak oxygen uptake in wheelchair sports; however, only a few protocols have been applied to evaluate these conditions in wheelchair basketball players. The purpose of this study was to compare physiological responses during maximal exercise testing with the use of ACE and WCT in wheelchair basketball players. Twelve elite male wheelchair basketball players participated in this study. The research was performed during a training camp of the Polish National Wheelchair Basketball Team. The study participants were divided into two functional categories: A (players with class 1.0 - 2.5) and B (players with class 3.0 - 4.5). Two main maximal exercise tests, i.e. wheelchair treadmill stress test (WCT test) and arm crank ergometer stress test (ACE test) were used to evaluate aerobic performance of the players. There were no statistically significant differences in aerobic tests between the players from both groups. The comparison of results achieved in two aerobic tests performed on WCT and ACE did not reveal any significant differences between the analyzed variables (peak heart rate (HRpeak), peak oxygen uptake (VO2peak), minute ventilation (VE), anaerobic threshold (AT), lactate concentration (LApeak), and a drop in lactate concentration (%LA)). Strong correlations between results achieved in WCT and ACE tests were found for VO2peak, VE and LApeak. The main conclusion of the study is that both WCT and ACE tests may be useful when determining aerobic capacity of wheelchair basketball players. Moreover, both protocols can be used by athletes regardless of their functional capabilities and types of impairment. PMID:29340005

  12. Test-retest reliability and construct validity of the Aspects of Wheelchair Mobility Test as a measure of the mobility of wheelchair users.

    Science.gov (United States)

    Rispin, Karen L; Huff, Kara; Wee, Joy

    2017-01-01

    The Aspects of Wheelchair Mobility Test (AWMT) was developed for use in a repeated measures format to provide comparative effectiveness data on mobility facilitated by different wheelchair types. It has been used in preliminary studies to compare the mobility of wheelchairs designed for low-resource areas and is intended to be simple and flexible enough so as to be used in low-technology settings. However, to reliably compare the impact of different types of wheelchairs on the mobility of users, a measure must first be a reliable and valid measure of mobility. This study investigated the test-retest reliability and concurrent validity for the AWMT 2.0 as a measure of mobility. For reliability testing, participants in a low-resource setting completed the tests twice in their own wheelchairs at least one week apart. For concurrent validity, participants also completed the Wheelchair Skills Test Questionnaire (WST-Q), a related but not identical validated assessment tool. Concurrent validity was indicated by a significant positive correlation with an r value of 0.7 between the WST-Q capacity score and the AWMT 2.0 score. Test-retest reliability was confirmed by an intraclass correlation coefficient greater than 0.7 between the two trials. Results support the preliminary reliability and validity of the AWMT 2.0, supporting its effectiveness in comparing the mobility provided by different wheelchair types. This information can be used to enable effective use of limited funds for wheelchair selection at individual and organisational scales.

  13. Superconducting Aero Propulsion Motor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Superconducting electric propulsion systems will yield improvements in total ownership costs due to the simplicity of electric drive when compared with gas turbine...

  14. Propulsion IVHM Technology Experiment Overview

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA researchers recently demonstrated successful real-time fault detection and isolation of a virtual reusable launch vehicle main propulsion system. Using a...

  15. Propulsion Systems Laboratory, Bldg. 125

    Data.gov (United States)

    Federal Laboratory Consortium — The Propulsion Systems Laboratory (PSL) is NASAs only ground test facility capable of providing true altitude and flight speed simulation for testing full scale gas...

  16. How Does Rocket Propulsion Work?

    Indian Academy of Sciences (India)

    /fulltext/reso/016/01/0065-0068. Keywords. Propulsion; thrust; reaction. Author Affiliations. Chandrahas M Halai1. 12, Maheshwar Chhaya 60 Feet Road, Ghatkopar (East) Mumbai 400 077, India. Resonance – Journal of Science Education.

  17. [Physical activity in wheelchair users with spinal cord injury: prerequisites for and effects of an active lifestyle].

    Science.gov (United States)

    de Groot, Sonja; Valent, Linda J M; van Koppenhagen, Casper F; Broeksteeg, Rogier; Post, Marcel W M; van der Woude, Lucas H V

    2013-01-01

    Wheelchair users with spinal cord injury generally have a relatively inactive lifestyle. Several studies have shown that an inactive lifestyle is associated with a lower fitness level, poorer health, reduced social participation and a lower quality of life for wheelchair users. There are a number of ways in which wheelchair users can remain active in daily life, for instance, by using a wheelchair or handbike for mobility instead of taking the car, and by participating in sports or wheelchair sports. Some prerequisites should be met to enable wheelchair users to have a more active lifestyle: the wheelchair should be optimally adjusted and the everyday environment, including sport facilities, should be easily accessible. An active lifestyle often also requires a change in attitude or behaviour. General practitioners, other primary healthcare providers and rehabilitation professionals can help in this respect.

  18. Hypersonic propulsion. Past and present

    OpenAIRE

    Sánchez Tarifa, Carlos

    1990-01-01

    The change of the concept of hypersonic speed with time is in the first place briefly discussed. The evolution of the hypersonic propulsion is restricted to the history of the ramjets. Considering the abundance of excellent literature on the subject only the most remarkable achievements are commented. Less divulged historical events, such as the propulsion of helicopters by ramjets are discussed with more detail, and special attention is given to the contributions of Spain to supersonic combu...

  19. Electric propulsion for small satellites

    Science.gov (United States)

    Keidar, Michael; Zhuang, Taisen; Shashurin, Alexey; Teel, George; Chiu, Dereck; Lukas, Joseph; Haque, Samudra; Brieda, Lubos

    2015-01-01

    Propulsion is required for satellite motion in outer space. The displacement of a satellite in space, orbit transfer and its attitude control are the task of space propulsion, which is carried out by rocket engines. Electric propulsion uses electric energy to energize or accelerate the propellant. The electric propulsion, which uses electrical energy to accelerate propellant in the form of plasma, is known as plasma propulsion. Plasma propulsion utilizes the electric energy to first, ionize the propellant and then, deliver energy to the resulting plasma leading to plasma acceleration. Many types of plasma thrusters have been developed over last 50 years. The variety of these devices can be divided into three main categories dependent on the mechanism of acceleration: (i) electrothermal, (ii) electrostatic and (iii) electromagnetic. Recent trends in space exploration associate with the paradigm shift towards small and efficient satellites, or micro- and nano-satellites. A particular example of microthruster considered in this paper is the micro-cathode arc thruster (µCAT). The µCAT is based on vacuum arc discharge. Thrust is produced when the arc discharge erodes some of the cathode at high velocity and is accelerated out the nozzle by a Lorentz force. The thrust amount is controlled by varying the frequency of pulses with demonstrated range to date of 1-50 Hz producing thrust ranging from 1 µN to 0.05 mN.

  20. Evaluation of a Shoulder Injury Prevention Program in Wheelchair Basketball.

    Science.gov (United States)

    Wilroy, Jereme; Hibberd, Elizabeth

    2017-11-15

    Previous literature has theorized that alterations in shoulder physical characteristics are present in wheelchair athletes and contribute to shoulder pain and injury. Limited empirical evidence is present that evaluates the effectiveness of a shoulder injury prevention program focusing on improving these altered characteristics. To evaluate the effectiveness of a 6-week intervention program at improving characteristics that increases the risk of developing pain or shoulder injury. Pre and post-test. Home-based and controlled laboratory. Seven collegiate wheelchair athletes. Shoulder range of motion (ROM) and scapular muscle strength were assessed, and a 5-minute injury prevention program was taught to participants. Participants completed the intervention 3 times per week for 6 weeks. Following completion of the program, a post-intervention screening was performed. Internal/external rotation ROM, retraction strength, and internal/external rotation strength. Participants experienced a significant improvement in dominant limb shoulder internal rotation ROM (t6=3.56,p=0.012) with an average increase of 11.4° of IR ROM, and a significant improvement in dominant limb shoulder external rotation (ER) ROM (t6=2.79,p=0.032) with an average increase of 8.0° of ER ROM. There were no significant increases in shoulder IR or ER strength and scapular retraction strength (p>0.05). Improvements in ROM have previously been linked to decreases in shoulder pain and injury in other upper-extremity dominant sports by improving scapular kinematics. These results provide evidence that a 6-week strengthening and stretching intervention program may decrease risk factors for shoulder injury in wheelchair athletics.

  1. Elite-adapted wheelchair sports performance: a systematic review.

    Science.gov (United States)

    Perret, Claudio

    2017-01-01

    Elite-adapted sports performance has considerably improved over the last decades and winning or losing races at Paralympic Games is often a matter of a split second. In other words, every single detail counts, which underlines the necessity of optimizing training interventions and equipment for athletes in order to achieve top-class performance. However, to date, studies which include Paralympic elite athletes are scarce. A comprehensive literature search was performed to identify potential strategies and interventions in order to optimize elite-adapted wheelchair sports performance, whereas the focus lay on respiratory muscle training (RMT), cooling (CI) and nutritional interventions (NI) as well as on individual equipment adaptations (IEA). The total number of studies identified for the final analysis was six for RMT, two for CI, three for NI and seven for IEA, respectively. Results point predominantly towards performance enhancing benefits for CI and IEA, whereas NI and RMT provided inhomogenous findings. In comparison to the able-bodied population, research in the field of Paralympic elite sport is scarce. CI and IEA seem to have significant performance enhancing benefits, whereas NI and RMT revealed controversial findings. However, due to the limited number of elite athletes with a spinal cord injury available to participate in scientific studies, general conclusions are difficult to make at this stage and in daily practice recommendations are still given mainly on an individual basis or based on personal experiences of coaches, athletes and scientists. Implications for Rehabilitaton Based on the knowledge gained in elite sports, wheelchair equipment could be optimized also for daily use. Elite sports performance could inspire wheelchair users to achieve their personal fitness goals.

  2. Wheelchair type biomedical system with event-recorder function.

    Science.gov (United States)

    Han, Dong-Kyoon; Kim, Jong-Myoung; Cha, Eun-Jong; Lee, Tae-Soo

    2008-01-01

    The present study is about a biometric system for a wheelchair, which can measure both bio-signal (ECG-Electrocardiogram, BCG-Ballistocardiogram) and kinetic signal (acceleration) simultaneously and send the data to a remote medical server. The equipment was developed with the object of building a system that measures the bio-signal and kinetic signal of a subject who is moving or at rest on a wheelchair and transmits the measured signals to a remote server through a CDMA (Code Division Multiple Access) network. The equipment is composed of body area network and remote medical server. The body area network was designed to obtain bio-signal and kinetic signal simultaneously and, on the occurrence of an event, to transmit data to a remote medical server through a CDMA network. The remote medical server was designed to display event data transmitted from the body area network in real time. The performance of the developed system was evaluated through two experiments. First, we measured battery life on the occurrence of events, and second, we tested whether biometric data are transmitted accurately to the remote server on the occurrence of an event. In the first experiment using the developed equipment, events were triggered 16 times and the battery worked stably for around 29 hours. In the second experiment, when an event took place, the corresponding data were transmitted accurately to the remote medical server through a CDMA network. This system is expected to be usable for the healthcare of those moving on a wheelchair and applicable to a mobile healthcare system.

  3. Wheelchair users, access and exclusion in South African higher education

    Directory of Open Access Journals (Sweden)

    Desire Chiwandire

    2017-01-01

    Full Text Available Background: South Africa’s Constitution guarantees everyone, including persons with disabilities, the right to education. A variety of laws are in place obliging higher education institutions to provide appropriate physical access to education sites for all. In practice, however, many buildings remain inaccessible to people with physical disabilities.Objectives: To describe what measures South African universities are taking to make their built environments more accessible to students with diverse types of disabilities, and to assess the adequacy of such measures.Method: We conducted semi-structured in-depth face-to-face interviews with disability unit staff members (DUSMs based at 10 different public universities in South Africa.Results: Challenges with promoting higher education accessibility for wheelchair users include the preservation and heritage justification for failing to modify older buildings, ad hoc approaches to creating accessible environments and failure to address access to toilets, libraries and transport facilities for wheelchair users.Conclusion: South African universities are still not places where all students are equally able to integrate socially. DUSMs know what ought to be done to make campuses more accessible and welcoming to students with disabilities and should be empowered to play a leading role in sensitising non-disabled members of universities, to create greater awareness of, and appreciation for, the multiple ways in which wheelchair user students continue to be excluded from full participation in university life. South African universities need to adopt a systemic approach to inclusion, which fosters an understanding of inclusion as a fundamental right rather than as a luxury.

  4. A Better Engineering Design: Low Cost Assistance Kit for Manual Wheelchair Users with Enhanced Obstacle Detection

    Directory of Open Access Journals (Sweden)

    Dryvendra

    2015-09-01

    Full Text Available This paper proposes a better engineering design of an assistance kit for manual wheelchair users. The design is aimed to enhance the detection of obstacles in the travelling path of the wheelchair user at low cost. This is facilitated by microcontroller and sensor technologies. The proposed design provides the intended user with obstacle detection, light detection, a light emitting diode (LED emergency light system, and an emergency alarm system. The microcontroller is the main controller that receives input from the sensors and produces output to the light crystal display (LCD screen, the LED emergency light system, and the emergency alarm system. An ultrasonic sensor is used to detect the presence of obstacles directly behind the wheelchair. If any obstacle exists behind the wheelchair within a set range, the system will alert the wheelchair user through different alarm sounds. In the case of absence of light, the LED emergency light system is activated and turns on a light source, which is attached to the wheelchair to provide a bright and clear path for the user. The distance between the obstacle and the wheelchair, and the status of the LED emergency light system are displayed on the LCD screen.

  5. Brain-Computer Interface for Control of Wheelchair Using Fuzzy Neural Networks

    Directory of Open Access Journals (Sweden)

    Rahib H. Abiyev

    2016-01-01

    Full Text Available The design of brain-computer interface for the wheelchair for physically disabled people is presented. The design of the proposed system is based on receiving, processing, and classification of the electroencephalographic (EEG signals and then performing the control of the wheelchair. The number of experimental measurements of brain activity has been done using human control commands of the wheelchair. Based on the mental activity of the user and the control commands of the wheelchair, the design of classification system based on fuzzy neural networks (FNN is considered. The design of FNN based algorithm is used for brain-actuated control. The training data is used to design the system and then test data is applied to measure the performance of the control system. The control of the wheelchair is performed under real conditions using direction and speed control commands of the wheelchair. The approach used in the paper allows reducing the probability of misclassification and improving the control accuracy of the wheelchair.

  6. [Factors associated with the use of wheelchairs by institutionalized elderly people].

    Science.gov (United States)

    Alves, Elysama Fernandes; Bezerra, Poliana Penasso

    2017-11-01

    Due to the high prevalence of wheel-chair use by institutionalized elderly people, the scope of this research was to verify whether factors involving gender, age, education, length of institutionalization, comorbidities, cognition and functionality are associated with the use of such equipment, as well as ascertain the reasons for use according to the perceptions of the elderly. It is a cross-sectional descriptive study that included 55 elderly people subdivided into G1 (locomotion without assistance) and G2 (wheelchair users). Analysis of the profile in medical records, cognition and functionality by the Mini-Mental State Examination and Barthel index was conducted. Wheelchair users asked about the factors that lead to wheelchair use were recorded: 33 (60%) of the elderly were in G1 and 22 (40%) in G2. There were differences between the groups with respect to functionality (p = 0.005). The elderly who have not suffered a stroke are less likely to use a wheelchair (OR: 0.09; 95% CI: 0.02 to 0.36). Elderly wheelchair users reported: fear of falling, pain, tiredness, weakness in the legs, difficulty walking and lack of assistance in walking. Strokes and functionality are associated with wheelchair use. Knowledge of these factors and the reasons reported by the elderly may enable alternatives of prevention to be defined.

  7. Collection of in-Field Impact Loads Acting on a Rugby Wheelchair Frame

    Directory of Open Access Journals (Sweden)

    Francesco Bettella

    2018-02-01

    Full Text Available This work was included in a wider project oriented to the improvement of residual neuromuscular skills in disabled athletes playing wheelchair rugby: the wheelchair rugby Italian national team was involved and tests allowed to analyse the impact loads on a rugby wheelchair frame. The frame of a rugby wheelchair offensive model, made by OffCarr Company, was instrumented with four strain gauge bridges in four different points. Then, three test types were conducted in laboratory: two static calibrations with the application of known loads, the first with horizontal load and the second with vertical load, and a dynamic horizontal calibration, impacting against a fix load cell in order to validate the results of horizontal static calibration. Finally, a test session took place in the field with the collaboration of two team players. The test consisted in voluntary frontal impacts between the two players, starting from 6 meters distance each other. The opponent of the instrumented wheelchair was a defender. From this test, the value of the horizontal load received by the frame in the impact instant was quantified. Moreover, also the vertical load acting on the wheelchair during the rebound of the player after the hit was evaluated: these informations were useful to the wheelchair frame manufacturer for the proper static, impact and fatigue design.

  8. Magnetohydrodynamic sea water propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Petrick, M.; Thomas, A.; Genens, L.; Libera, J.; Nietert, R.; Bouillard, J.; Pierson, E.; Hill, D.; Picologlou, B.; Ohlsson, O.; Kasprzyk, T.; Berry, G.

    1991-12-31

    An experimental and theoretical investigation of a large scale MHD propulsor has been undertaken whose objectives are to (1) investigate the transient and steady state performance of the thruster over operating parameter ranges that are compatible with achievement of high efficiency, (2) to quantify the principal loss mechanisms within the thruster and (3) to obtain preliminary hydroacoustic data. The performance of the thruster was first investigated theoretically with a 3-D code to quantify the loss mechanisms and identify experimental parameter ranges of interest. The loss mechanisms of interest are ohmic losses within the channel and those resulting from electrical currents at the entrance and exit of the thruster, and enhanced frictional losses. The analysis indicated that the relative importance of the loss mechanisms was a function of the thruster design and operating parameters. The experimental investigation of the large scale propulsor is being conducted on a sea water test facility that was designed to match the capabilities of a large 6-T superconducting magnet. The facility design was such that {approximately}90{degrees} of all losses occurred within the propulsion test train (inlet nozzle, propulsor and diffuser) thus facilitating isolation of the loss mechanisms. The test thruster itself is heavily instrumented to provide local measurements of velocity, pressure, and electric fields. The predicted overall thruster performance and value of the loss mechanisms will be compared with measured values. Comparisons will also be presented of the voltage gradients between electrodes, overall thruster efficiency, axial pressure gradients across the propulsor, change in velocity profiles, axial and vertical current distributions and exit distribution of the electrolytic gases.

  9. Magnetohydrodynamic sea water propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Petrick, M.; Thomas, A.; Genens, L.; Libera, J.; Nietert, R.; Bouillard, J.; Pierson, E.; Hill, D.; Picologlou, B.; Ohlsson, O.; Kasprzyk, T.; Berry, G.

    1991-01-01

    An experimental and theoretical investigation of a large scale MHD propulsor has been undertaken whose objectives are to (1) investigate the transient and steady state performance of the thruster over operating parameter ranges that are compatible with achievement of high efficiency, (2) to quantify the principal loss mechanisms within the thruster and (3) to obtain preliminary hydroacoustic data. The performance of the thruster was first investigated theoretically with a 3-D code to quantify the loss mechanisms and identify experimental parameter ranges of interest. The loss mechanisms of interest are ohmic losses within the channel and those resulting from electrical currents at the entrance and exit of the thruster, and enhanced frictional losses. The analysis indicated that the relative importance of the loss mechanisms was a function of the thruster design and operating parameters. The experimental investigation of the large scale propulsor is being conducted on a sea water test facility that was designed to match the capabilities of a large 6-T superconducting magnet. The facility design was such that {approximately}90{degrees} of all losses occurred within the propulsion test train (inlet nozzle, propulsor and diffuser) thus facilitating isolation of the loss mechanisms. The test thruster itself is heavily instrumented to provide local measurements of velocity, pressure, and electric fields. The predicted overall thruster performance and value of the loss mechanisms will be compared with measured values. Comparisons will also be presented of the voltage gradients between electrodes, overall thruster efficiency, axial pressure gradients across the propulsor, change in velocity profiles, axial and vertical current distributions and exit distribution of the electrolytic gases.

  10. From big data to rich data: The key features of athlete wheelchair mobility performance.

    Science.gov (United States)

    van der Slikke, R M A; Berger, M A M; Bregman, D J J; Veeger, H E J

    2016-10-03

    Quantitative assessment of an athlete׳s individual wheelchair mobility performance is one prerequisite needed to evaluate game performance, improve wheelchair settings and optimize training routines. Inertial Measurement Unit (IMU) based methods can be used to perform such quantitative assessment, providing a large number of kinematic data. The goal of this research was to reduce that large amount of data to a set of key features best describing wheelchair mobility performance in match play and present them in meaningful way for both scientists and athletes. To test the discriminative power, wheelchair mobility characteristics of athletes with different performance levels were compared. The wheelchair kinematics of 29 (inter-)national level athletes were measured during a match using three inertial sensors mounted on the wheelchair. Principal component analysis was used to reduce 22 kinematic outcomes to a set of six outcomes regarding linear and rotational movement; speed and acceleration; average and best performance. In addition, it was explored whether groups of athletes with known performance differences based on their impairment classification also differed with respect to these key outcomes using univariate general linear models. For all six key outcomes classification showed to be a significant factor (pwheelchair mobility performance in match play. The key kinematic outcomes were displayed in an easy to interpret way, usable for athletes, coaches and scientists. This standardized representation enables comparison of different wheelchair sports regarding wheelchair mobility, but also evaluation at the level of an individual athlete. By this means, the tool could enhance further development of wheelchair sports in general. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Policy implementation in wheelchair service delivery in a rural South African setting

    Directory of Open Access Journals (Sweden)

    Surona Visagie

    2013-01-01

    Full Text Available Background: Wheelchairs allow users to realise basic human rights and improved quality of life. South African and international documents guide rehabilitation service delivery and thus the provision of wheelchairs. Evidence indicates that rehabilitation policy implementation gaps exist in rural South Africa.Objectives: The aim of this article was to explore the extent to which wheelchair service delivery in a rural, remote area of South Africa was aligned with the South African National Guidelines on Provision of Assistive Devices, The United Nations Convention on the Rights of Persons with Disabilities and The World Health Organization Guidelines on Provision of Wheelchairs in Less-Resourced Settings.Method: Qualitative methods were used. Data were collected through semi-structured interviews with 22 participants who were identified through purposive sampling. Content analysis of data was preformed around the construct of wheelchair service delivery.Results: Study findings identified gaps between the guiding documents and wheelchair service delivery. Areas where gaps were identified included service aspects such as referral, assessment, prescription, user and provider training, follow up, maintenance and repair as well as management aspects such as staff support, budget and monitoring. Positive findings related to individual assessments, enthusiastic and caring staff and the provision of wheelchairs at no cost.Conclusion: The gaps in policy implementation can have a negative impact on users and the service provider. Inappropriate or no wheelchairs limit user function, participation and quality of life. In addition, an inappropriate wheelchair will have a shorter lifespan, requiring frequent repairs and replacements with cost implications for the service provider.

  12. An examination of the Rosenberg Self-Esteem Scale using collegiate wheelchair basketball student athletes.

    Science.gov (United States)

    Vermillion, Mark; Dodder, Richard A

    2007-04-01

    The purpose was to examine the construct validity of the Rosenberg Self-esteem Scale (RSES). The construct validity of the scale was examined by applying it to collegiate wheelchair basketball student athletes at an NCAA sanctioned wheelchair basketball tournament at a mid-sized university in the south central United States (N=68). In accordance with previous research on the scale, Cronbach alpha was .86; confirmatory factor analysis supported a one-factor structure. The scale is useful for measuring global self-esteem in collegiate wheelchair basketball student athletes.

  13. Wheelchair users' perceptions of and experiences with power assist wheels.

    Science.gov (United States)

    Giacobbi, Peter R; Levy, Charles E; Dietrich, Frederick D; Winkler, Sandra Hubbard; Tillman, Mark D; Chow, John W

    2010-03-01

    To assess wheelchair users' perceptions of and experiences with power assist wheels using qualitative interview methods. Qualitative evaluations were conducted in a laboratory setting with a focus on users' experiences using power assist wheel in their naturalistic environments. Participants consisted of seven women and 13 men (M(age) = 42.75, SD = 14.68) that included one African American, one Hispanic, 17 whites, and one individual from Zambia. Qualitative interviews were conducted before, during, and after use of a power assist wheel. Main outcome measures included the wheelchair users' evaluations and experiences related to the use of power assist wheels. The primary evaluations included wheeling on challenging terrains, performance of novel activities, social/family aspects, fatigue, and pain. These descriptions indicated that most participants perceived positive experiences with the power assist wheels, including access to new and different activities. Secondary evaluations indicated that the unit was cumbersome and prohibitive for some participants because of difficulties with transport in and out of a vehicle and battery life. Most participants felt that power assist wheels provided more independence and social opportunities. The power assist wheel seems to offer physical and social benefits for most wheelers. Clinicians should consider users' home environment and overall life circumstances before prescribing.

  14. Wheelchair collaborative control for disabled users navigating indoors.

    Science.gov (United States)

    Urdiales, Cristina; Fernández-Carmona, Manuel; Peula, José M; Cortés, Ulises; Annichiaricco, Roberta; Caltagirone, Carlo; Sandoval, Francisco

    2011-07-01

    Mobility is of key importance for autonomous living. Persons with severe disabilities may be assisted by robotic wheelchairs when manual control is not possible. However, these persons should contribute to control as much as they can to avoid loss of residual skills and frustration. Traditionally, wheelchair shared control approaches either give control to person or robot depending on the situation. We propose a new shared control technique where robot and person contribute simultaneously to control. Their commands are weighted according to their respective local efficiencies and then combined via a reactive navigation strategy. Thus, assistance adapts to the user's needs. We refer to this approach as collaborative control. Collaborative control was tested in a home environment in Fondazione Santa Lucia (Rome) by 18 volunteers presenting different degrees of physical and cognitive disability. All of them successfully finished a complex test path with assistance. Both users and caregivers' opinion on the system was very positive. Acceptance was very good according to the psychosocial impact of assistive devices scale. Collaborative control adapts to the person's needs and assists him/her when necessary, locally compensating any problem related to specific disabilities. An ANOVA returned a p-value of 0.016, meaning that there is significant improvement in task performance when collaborative control is used. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Training and development of Canadian wheelchair basketball players.

    Science.gov (United States)

    Dehghansai, N; Lemez, S; Wattie, N; Baker, J

    2017-06-01

    Considering the growth in research, examining the development of mainstream sport athletes over the past two decades, studies examining development of athletes with disabilities have been surprisingly limited. While similarities in developmental trajectories between the two cohorts may exist regarding factors such as the value of practice, which tend to be universal regardless of context, disability-related issues (e.g. whether the disability was congenital or acquired) may influence the course of development, affecting variables such as starting age, training and developmental milestones. Fifty-two male and female athletes training with the Wheelchair Basketball Canada National Academy provided detailed training histories. Athletes illustrated similar developmental patterns (e.g. milestones, training adjustments) as they progressed through their sporting career. However, athletes with congenital disabilities started participation in wheelchair basketball and unorganised practice at significantly younger ages (t 49  = -4.35, p career milestones (e.g. national debuts) at similar ages. Athletes' disability severity did not influence their progress through the developmental milestones and time devoted to training throughout their sporting career. Future work may consider examining developmental trajectories and training histories of athletes in various parasports to extend our understanding of their development and skill acquisition.

  16. Inclusive fashion, recognizing the need of the child wheelchair

    Directory of Open Access Journals (Sweden)

    Rosângela Elisa de Sousa

    2016-12-01

    Full Text Available This project addresses social inclusion, as a resource to be stimulated by the development of fashion products. Taking into account this market demand research, part of the project, identified aspects of use, accessibility, comfort and perception of parents and therapists with regard to dress, undress and cognitive development in relation to clothing. The audience researched this project were wheelchair children with age range from eight to twelve years, parents and professionals in the health field, such as Physiotherapists, Physical Educator, Occupational Therapist and psychologists, members of institutions CEAEHH - Centro de Atividades Especiais Helena Holanda e FUNAD – Fundação Centro Integrado de Apoio ao Portador de Deficiência, João Pessoa - PB, supporters this project through the sale of infrastructure and public access. The data resulted in the development of a fashion collection with differentiated modeling, versatility of uses combined with an aesthetic framework that prioritized the inclusion of wheelchair-bound child in society through the use of the usual market trends in the children's segment.

  17. Hypersonic propulsion - Breaking the thermal barrier

    Science.gov (United States)

    Weidner, J. P.

    1993-01-01

    The challenges of hypersonic propulsion impose unique features on the hypersonic vehicle - from large volume requirements to contain cryogenic fuel to airframe-integrated propulsion required to process sufficient quantities of air. Additional challenges exist in the design of the propulsion module that must be capable of efficiently processing air at very high enthalpies, adding and mixing fuel at supersonic speeds and expanding the exhaust products to generate thrust greater than drag. The paper explores the unique challenges of the integrated hypersonic propulsion system, addresses propulsion cycle selection to cope with the severe thermal environment and reviews the direction of propulsion research at hypervelocity speeds.

  18. Main Propulsion Test Article (MPTA)

    Science.gov (United States)

    Snoddy, Cynthia

    2010-01-01

    Scope: The Main Propulsion Test Article integrated the main propulsion subsystem with the clustered Space Shuttle Main Engines, the External Tank and associated GSE. The test program consisted of cryogenic tanking tests and short- and long duration static firings including gimbaling and throttling. The test program was conducted on the S1-C test stand (Position B-2) at the National Space Technology Laboratories (NSTL)/Stennis Space Center. 3 tanking tests and 20 hot fire tests conducted between December 21 1 1977 and December 17, 1980 Configuration: The main propulsion test article consisted of the three space shuttle main engines, flightweight external tank, flightweight aft fuselage, interface section and a boilerplate mid/fwd fuselage truss structure.

  19. LASL nuclear rocket propulsion program

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, R.E.

    1956-04-01

    The immediate objective of the LASL nuclear propulsion (Rover) program is the development of a heat exchanger reactor system utilizing uranium-graphite fuel elements and ammonia propellant. This program is regarded as the first step in the development of nuclear propulsion systems for missiles. The major tasks of the program include the investigation of materials at high temperatures, development of fuel elements, investigation of basic reactor characteristics, investigation of engine control problems, detailed engine design and ground testing. The organization and scheduling of the initial development program have been worked out in some detail. Only rather general ideas exist concerning the projection of this work beyond 1958.

  20. Wheelchair Basketball: As Intense and Emotional as the "Able-Bodied" Game.

    Science.gov (United States)

    Lederman, Douglas

    1988-01-01

    While only five colleges sponsor all-student wheelchair basketball teams, and budgets and public awareness are very limited, the sport's proponents believe it is doing a service for both its athletes and the general public. (MSE)

  1. Driving Control for Electric Power Assisted Wheelchair Based on Regenerative Brake

    Science.gov (United States)

    Seki, Hirokazu; Takahashi, Kazuki; Tadakuma, Susumu

    This paper describes a novel safety driving control scheme for electric power assisted wheelchairs based on the regenerative braking system. “Electric power assisted wheelchair” which assists the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people, however, the safe and secure driving performance especially on downhill roads must be further improved because electric power assisted wheelchairs have no braking devices. The proposed control system automatically switches the driving mode, from “assisting mode” to “braking mode”, based on the wheelchair's velocity and the declined angle and smoothly suppresses the wheelchair's acceleration based on variable duty ratio control in order to realize the safety driving and to improve the ride quality. Some experiments on the practical roads and subjective evaluation show the effectiveness of the proposed control system.

  2. Wheelchair rugby improves pulmonary function in people with tetraplegia after 1 year of training.

    Science.gov (United States)

    Moreno, Marlene A; Paris, Juliana V; Sarro, Karine J; Lodovico, Angélica; Silvatti, Amanda P; Barros, Ricardo M L

    2013-01-01

    This study investigated the effects of 1 year of regular wheelchair rugby training on the pulmonary function of subjects with tetraplegia. A total of 15 male subjects with tetraplegia participated in this study and were divided into an experimental group of rugby players (n = 8) and a control group (n = 7) of sedentary tetraplegic subjects. Both groups underwent spirometry, and the experimental group was tested before and after participating of a regular 1-year program of wheelchair rugby training. At the beginning of the training program, all the subjects presented reduced pulmonary function compared with predicted values (p values after 1 year of regular wheelchair rugby training. The regression analysis between total training time and spirometric variables FVC (r = 0.97, p values. This study showed that regular wheelchair rugby training can improve the pulmonary function of subjects with spinal cord injuries.

  3. Catheter length preference in wheelchair-using men who perform routine clean intermittent catheterization

    National Research Council Canada - National Science Library

    Costa, J A; Menier, M; Doran, T J; Köhler, T S

    2013-01-01

    Prospective, unblinded, multicenter, randomized, controlled, cross-over study assessing user preference and ease of use characteristics of two gel intermittent catheters in 81 self-catheterizing wheelchair-using men...

  4. Effect of service dogs on manual wheelchair users with spinal cord injury: a pilot study

    National Research Council Canada - National Science Library

    Hubert, Geoffroy; Tousignant, Michel; Routhier, François; Corriveau, Hélène; Champagne, Noël

    2013-01-01

    Service dogs help people with mobility impairments. They are trained to perform a variety of tasks, such as opening doors, retrieving the telephone, picking up objects, and pulling manual wheelchairs (MWCs...

  5. Development of a Wheelchair Skills Home Program for Older Adults Using a Participatory Action Design Approach

    Directory of Open Access Journals (Sweden)

    Edward M. Giesbrecht

    2014-01-01

    Full Text Available Restricted mobility is the most common impairment among older adults and a manual wheelchair is often prescribed to address these limitations. However, limited access to rehabilitation services results in older adults typically receiving little or no mobility training when they receive a wheelchair. As an alternative and novel approach, we developed a therapist-monitored wheelchair skills home training program delivered via a computer tablet. To optimize efficacy and adherence, principles of self-efficacy and adult learning theory were foundational in the program design. A participatory action design approach was used to engage older adult wheelchair users, care providers, and prescribing clinicians in an iterative design and development process. A series of prototypes were fabricated and revised, based on feedback from eight stakeholder focus groups, until a final version was ready for evaluation in a clinical trial. Stakeholder contributions affirmed and enhanced the foundational theoretical principles and provided validation of the final product for the target population.

  6. An independent shopping experience for wheelchair users through augmented reality and RFID.

    Science.gov (United States)

    Rashid, Zulqarnain; Pous, Rafael; Norrie, Christopher S

    2017-06-23

    People with physical and mobility impairments continue to struggle to attain independence in the performance of routine activities and tasks. For example, browsing in a store and interacting with products located beyond an arm's length may be impossible without the enabling intervention of a human assistant. This research article describes a study undertaken to design, develop, and evaluate potential interaction methods for motor-impaired individuals, specifically those who use wheelchairs. Our study includes a user-centered approach, and a categorization of wheelchair users based upon the severity of their disability and their individual needs. We designed and developed access solutions that utilize radio frequency identification (RFID), augmented reality (AR), and touchscreen technologies in order to help people who use wheelchairs to carry out certain tasks autonomously. In this way, they have been empowered to go shopping independently, free from reliance upon the assistance of others. A total of 18 wheelchair users participated in the completed study.

  7. Development of a Wheelchair Skills Home Program for Older Adults Using a Participatory Action Design Approach

    Science.gov (United States)

    Giesbrecht, Edward M.; Miller, William C.; Mitchell, Ian M.; Woodgate, Roberta L.

    2014-01-01

    Restricted mobility is the most common impairment among older adults and a manual wheelchair is often prescribed to address these limitations. However, limited access to rehabilitation services results in older adults typically receiving little or no mobility training when they receive a wheelchair. As an alternative and novel approach, we developed a therapist-monitored wheelchair skills home training program delivered via a computer tablet. To optimize efficacy and adherence, principles of self-efficacy and adult learning theory were foundational in the program design. A participatory action design approach was used to engage older adult wheelchair users, care providers, and prescribing clinicians in an iterative design and development process. A series of prototypes were fabricated and revised, based on feedback from eight stakeholder focus groups, until a final version was ready for evaluation in a clinical trial. Stakeholder contributions affirmed and enhanced the foundational theoretical principles and provided validation of the final product for the target population. PMID:25276768

  8. Interactive Collision Avoidance Based on Surrounding Mobility Type for an Intelligent Powered Wheelchair

    Directory of Open Access Journals (Sweden)

    Takuma Ito

    2013-05-01

    Full Text Available Abstract Electric powered wheelchairs have been developed for people with disabilities and the elderly who have difficulties walking and participating in social activities. However, for users with decreased cognitive abilities and judgment due to further aging, mobility aids that are not only powered but also intelligent are required. Intelligent powered wheelchairs with autonomous locomotion functions are one solution to this problem. This research focused on the complexity of coexisting “mobility types” on sidewalks and a prototype intelligent wheelchair equipped with interactive strategies for collision avoidance based on the surrounding mobility type was developed. In order to classify the mobility type of coexisting traffic participants, image-processing components combined with LIDAR were developed. Based on the classification results, the wheelchair selected and executed either a changing-lanes strategy or deceleration strategy autonomously.

  9. Electrolysis Propulsion Provides High-Performance, Inexpensive, Clean Spacecraft Propulsion

    Science.gov (United States)

    deGroot, Wim A.

    1999-01-01

    An electrolysis propulsion system consumes electrical energy to decompose water into hydrogen and oxygen. These gases are stored in separate tanks and used when needed in gaseous bipropellant thrusters for spacecraft propulsion. The propellant and combustion products are clean and nontoxic. As a result, costs associated with testing, handling, and launching can be an order of magnitude lower than for conventional propulsion systems, making electrolysis a cost-effective alternative to state-of-the-art systems. The electrical conversion efficiency is high (>85 percent), and maximum thrust-to-power ratios of 0.2 newtons per kilowatt (N/kW), a 370-sec specific impulse, can be obtained. A further advantage of the water rocket is its dual-mode potential. For relatively high thrust applications, the system can be used as a bipropellant engine. For low thrust levels and/or small impulse bit requirements, cold gas oxygen can be used alone. An added innovation is that the same hardware, with modest modifications, can be converted into an energy-storage and power-generation fuel cell, reducing the spacecraft power and propulsion system weight by an order of magnitude.

  10. Improvement of Sprint Performance in Wheelchair Sportsmen With Caffeine Supplementation.

    Science.gov (United States)

    Graham-Paulson, Terri S; Perret, Claudio; Watson, Phil; Goosey-Tolfrey, Victoria L

    2016-03-01

    Caffeine can be beneficial during endurance and repeated-sprint exercise in able-bodied individuals performing leg or whole-body exercise. However, little evidence exists regarding its effects during upper-body exercise. This study therefore aimed to investigate the effects of caffeine on sprint (SPR) and 4-min maximal-push (PUSH) performance in wheelchair sportsmen. Using a double-blind, placebo-controlled, crossover design, 12 male wheelchair rugby players (age 30.0 ± 7.7 y, body mass 69.6 ± 15.3 kg, training 11.1 ± 3.5 h/wk) completed 2 exercise trials, separated by 7-14 d, 70 min after ingestion of 4 mg/kg caffeine (CAF) or dextrose placebo (PLA). Each trial consisted of four 4-min PUSHes and 3 sets of 3 × 20-m SPRs, each separated by 4 min rest. Participants responded to the Felt Arousal (a measure of perceived arousal), Feeling (a measure of the affective dimension of pleasure/displeasure), and rating-of-perceived-exertion (RPE) scales. Salivary caffeine secretion rates were measured. Average SPR times were faster during CAF than PLA during SPR 1 and SPR 2 (P = .037 and .016). There was no influence of supplementation on PUSHes 2-4 (P > .099); however, participants pushed significantly farther during PUSH 1 after CAF than after PLA (mean ± SD 677 ± 107 and 653 ± 118 m, P = .047). There was no influence of CAF on arousal or RPE scores (P > .132). Feeling scores improved over the course of the CAF trial only (P = .017) but did not significantly differ between trials (P > .167). Pre-warm-up (45 min postingestion) salivary CAF secretion rates were 1.05 ± 0.94 and 0.08 ± 0.05 μg/min for CAF and PLA, respectively. Acute CAF supplementation can improve both 20-m-sprint performance and a 1-off bout of short-term endurance performance in wheelchair sportsmen.

  11. Factors associated with deep tissue injury in male wheelchair basketball players of a Japanese national team

    Directory of Open Access Journals (Sweden)

    Hirotaka Mutsuzaki

    2014-04-01

    Full Text Available Maintenance of the sporting activity of elite athletes in adapted sports can be difficult if a secondary disorder, such as a pressure ulcer, occurs. Pressure ulcers result from deep tissue injuries by external pressure. The purpose of this study was to use ultrasonography to investigate deep tissue injuries in male wheelchair basketball players of a Japanese national team, and to determine factors associated with the injuries (e.g., body mass index, class of wheelchair basketball, underlying disease, length of athletic career, and whether use of wheelchair is primarily for playing basketball. Twenty male Japanese wheelchair basketball players on the national team for the 2012 London Paralympic Games (12 representative players and eight candidate representative players participated in this study. The sacral region and bilateral ischial regions in each athlete were examined by ultrasonography to detect low-echoic lesions indicative of deep tissue injuries. Nine (45% players had low-echoic lesions, which were detected in 10 of 60 areas. Eight lesions were detected in the sacral region and two lesions were detected in the ischial region. More players with spinal cord injury had low-echoic lesions [9 (69.2% of 13 players], compared to players with skeletal system disease [0 (0% of 7 players, p = 0.002]. Players who used a wheelchair in daily life were more likely to have low-echoic lesions [8 (66.74% of 12 players], compared to players who primarily used a wheelchair for playing basketball [1 (12.5% of 8 players, p = 0.010]. Deep tissue injuries were detected in 45% of male Japanese wheelchair basketball players on the national team. Players with spinal cord injury and players who used a wheelchair in daily life were more likely to have deep tissue injuries, particularly in the sacral region. The lesions were small, but a periodic medical check should be performed to maintain athletes' sporting life.

  12. Design and validation of an intelligent wheelchair towards a clinically-functional outcome.

    Science.gov (United States)

    Boucher, Patrice; Atrash, Amin; Kelouwani, Sousso; Honoré, Wormser; Nguyen, Hai; Villemure, Julien; Routhier, François; Cohen, Paul; Demers, Louise; Forget, Robert; Pineau, Joelle

    2013-06-17

    Many people with mobility impairments, who require the use of powered wheelchairs, have difficulty completing basic maneuvering tasks during their activities of daily living (ADL). In order to provide assistance to this population, robotic and intelligent system technologies have been used to design an intelligent powered wheelchair (IPW). This paper provides a comprehensive overview of the design and validation of the IPW. The main contributions of this work are three-fold. First, we present a software architecture for robot navigation and control in constrained spaces. Second, we describe a decision-theoretic approach for achieving robust speech-based control of the intelligent wheelchair. Third, we present an evaluation protocol motivated by a meaningful clinical outcome, in the form of the Robotic Wheelchair Skills Test (RWST). This allows us to perform a thorough characterization of the performance and safety of the system, involving 17 test subjects (8 non-PW users, 9 regular PW users), 32 complete RWST sessions, 25 total hours of testing, and 9 kilometers of total running distance. User tests with the RWST show that the navigation architecture reduced collisions by more than 60% compared to other recent intelligent wheelchair platforms. On the tasks of the RWST, we measured an average decrease of 4% in performance score and 3% in safety score (not statistically significant), compared to the scores obtained with conventional driving model. This analysis was performed with regular users that had over 6 years of wheelchair driving experience, compared to approximately one half-hour of training with the autonomous mode. The platform tested in these experiments is among the most experimentally validated robotic wheelchairs in realistic contexts. The results establish that proficient powered wheelchair users can achieve the same level of performance with the intelligent command mode, as with the conventional command mode.

  13. A description of manual wheelchair skills training: current practices in Canadian rehabilitation centers.

    Science.gov (United States)

    Best, Krista L; Routhier, François; Miller, William C

    2015-01-01

    To describe current practices for manual wheelchair (MWC) skills training in Canadian rehabilitation centers. An online survey was sent to practice leaders in occupational (OT) and physical therapy (PT) at 87 Canadian rehabilitation centers. Responses were solicited from individuals who could report about wheelchair skills training at facilities with at least 10 beds designated for rehabilitation. Thirty-four questions asked about: (1) demographics, (2) components of MWC training, (3) amount of MWC skills training, (4) use of validated programs and (5) perceived barriers to using validated programs. Data were analyzed using summary statistics. About 68/87 responses were received primarily from OTs (42/68). Basic MWC skills training (e.g. wheel-locks) was consistently part of clinical practice (45/68), while advanced skills training (e.g. curb-cuts) was rare (8/68). On an average, 1-4 h of training was done (29/68). Validated training programs were used by 16/68, most of whom used them "rarely" (7/16). Common barriers to using validated programs were lack of time (43/68) and resources (39/68). Learning to use a wheelchair is important for those with ambulation impairments because the wheelchair enables mobility and social participation. Providing opportunities for advanced wheelchair skills training may enhance mobility and social participation in a safe manner. Implications for Rehabilitation There is evidence confirming the benefits of a validated wheelchair skills program, yet most clinicians do no not use them. A variety of perceived barriers may help to explain the limited use of existing programs, such as time, resources and knowledge. Effective knowledge translation efforts may help alleviate some of these barriers, and novel wheelchair training approaches may alleviate some burden on clinicians to help accommodate the increasing number of older wheelchair users.

  14. The Functional Classification and Field Test Performance in Wheelchair Basketball Players

    Directory of Open Access Journals (Sweden)

    Gil Susana María

    2015-06-01

    Full Text Available Wheelchair basketball players are classified in four classes based on the International Wheelchair Basketball Federation (IWBF system of competition. Thus, the aim of the study was to ascertain if the IWBF classification, the type of injury and the wheelchair experience were related to different performance field-based tests. Thirteen basketball players undertook anthropometric measurements and performance tests (hand dynamometry, 5 m and 20 m sprints, 5 m and 20 m sprints with a ball, a T-test, a Pick-up test, a modified 10 m Yo-Yo intermittent recovery test, a maximal pass and a medicine ball throw. The IWBF class was correlated (p<0.05 to the hand dynamometry (r= 0.84, the maximal pass (r=0.67 and the medicine ball throw (r= 0.67. Whereas the years of dependence on the wheelchair were correlated to the velocity (p<0.01: 5 m (r= −0.80 and 20 m (r= −0.77 and agility tests (r= −0.77, p<0.01. Also, the 20 m sprint with a ball (r= 0.68 and the T-test (r= −0.57 correlated (p<0.05 with the experience in playing wheelchair basketball. Therefore, in this team the correlations of the performance variables differed when they were related to the disability class, the years of dependence on the wheelchair and the experience in playing wheelchair basketball. These results should be taken into account by the technical staff and coaches of the teams when assessing performance of wheelchair basketball players.

  15. Active Tension Control for WT Wheelchair Robot by Using a Novel Control Law for Holonomic or Nonholonomic Systems

    Directory of Open Access Journals (Sweden)

    Jian Wang

    2013-01-01

    Full Text Available Interactional characteristics between WT wheelchair robot and stair environment are analyzed, and possible patterns of WT wheelchair robot during the stair-climbing process are summarized, with the criteria of the wheelchair robot for determining the pattern proposed. Aiming at WT wheelchair robot's complicated mechanism with holonomic constraints and combined with the computed torque method, a novel control law that is called active tension control is presented for holonomic or nonholonomic robotic systems, by which the wheelchair robot with a holonomic or nonholonomic mechanism can track the reference input of the constraint forces of holonomic or nonholonomic constraints as well as tracking the reference input of the generalized coordinate of each joint. A stateflow module of Matlab is used to simulate the entire stair-climbing process for WT wheelchair robot. A comparison of output curve with the reference input curve of each joint is made, with the effectiveness of the presented control law verified.

  16. THE FUTURE OF SPACECRAFT NUCLEAR PROPULSION

    OpenAIRE

    Jansen, Frank

    2014-01-01

    This paper summarizes the advantages of space nuclear power and propulsion systems. It describes the actual status of international power level dependent spacecraft nuclear propulsion missions, especially the high power EU-Russian MEGAHIT study including the Russian Megawatt-Class Nuclear Power Propulsion System, the NASA GRC project and the low and medium power EU DiPoP study. Space nuclear propulsion based mission scenarios of these studies are sketched as well.

  17. The Future of Spacecraft Nuclear Propulsion

    Science.gov (United States)

    Jansen, F.

    2014-06-01

    This paper summarizes the advantages of space nuclear power and propulsion systems. It describes the actual status of international power level dependent spacecraft nuclear propulsion missions, especially the high power EU-Russian MEGAHIT study including the Russian Megawatt-Class Nuclear Power Propulsion System, the NASA GRC project and the low and medium power EU DiPoP study. Space nuclear propulsion based mission scenarios of these studies are sketched as well.

  18. Using a smart wheelchair as a gaming device for floor-projected games: a mixed-reality environment for training powered-wheelchair driving skills.

    Science.gov (United States)

    Secoli, R; Zondervan, D; Reinkensmeyer, D

    2012-01-01

    For children with a severe disability, such as can arise from cerebral palsy, becoming independent in mobility is a critical goal. Currently, however, driver's training for powered wheelchair use is labor intensive, requiring hand-over-hand assistance from a skilled therapist to keep the trainee safe. This paper describes the design of a mixed reality environment for semi-autonomous training of wheelchair driving skills. In this system, the wheelchair is used as the gaming input device, and users train driving skills by maneuvering through floor-projected games created with a multi-projector system and a multi-camera tracking system. A force feedback joystick assists in steering and enhances safety.

  19. A proposed power assisted system of manual wheelchair based on universal design for eldery

    Science.gov (United States)

    Susmartini, Susy; Pryadhitama, Ilham; Herdiman, Lobes; Wahyufitriani, Cindy

    2017-11-01

    Difficulties in walking is high percentage case in the limitations mobility of the elderly. An assisted technology commonly used to help the elderly who have walking difficulty is a manual wheelchair. However, the elderly frequently experiences difficulties in operating manual wheelchair due to gradually degradation of their physical condition. Preliminary study results showed that the average grip strength of the hands of seven elderly subjects was 13.8 ± 6.96 kg and the value is relatively weak. In addition, the mean maximum speed of 7 elderly subjects when doing to round the wheelchair is 0.6 ± 0.2m / s. This value is only 56.4% compared with an average speed of 20-23-year age group (8 males), which is 1.1 ± 0.1 m / s. This shows that the elderly who have walking difficulty have low grip strength and speed in operating a wheelchair. On the other hand, manual wheelchairs suffer an inadequate technology solution to solve the problem. Therefore, an assistive technology is proposed to create mobility aid to accommodate the elderly needs. One approach used is Universal Design. This paper proposes a system of intervention in the manual wheelchair through the 7 principles of Universal Design approach. The preliminary principle has not been able to accommodate the needs of the elderly will become a reference in the proposed design of this study.

  20. The role of virtual reality technology in the assessment and training of inexperienced powered wheelchair users.

    Science.gov (United States)

    Harrison, A; Derwent, G; Enticknap, A; Rose, F D; Attree, E A

    The current paper provides quantitative and qualitative data concerning the application of two virtual environments to the assessment and training of inexperienced powered wheelchair users, both in terms of the ability to control the chair accurately without hitting objects in the environment (manoeuvrability) and in terms of being able to find ones way around a complex environment without becoming lost (route-finding). Six novice powered wheelchair users participated in the project, completing either the manoeuvrability or route finding components of the study. Performance measures were taken in real life pre and post training and throughout virtual reality sessions. Participants also completed a questionnaire regarding the aesthetics of the virtual environments and aspects of the powered wheelchair simulation. The participants rated the aesthetics of the virtual environments positively and engaged well with the virtual system. However, they found the manoeuvrability tasks considerably more difficult in virtual reality (VR) than in real life. Some difficulties with controlling the simulated wheelchair were apparent. Some improvements on virtual and real life manoeuvrability tasks and route finding were noted following conventional and virtual training. The study indicated that the two virtual environments represent a potentially useful means of assessing and training novice powered wheelchair users. The virtual environments however must become less challenging if they are to represent a motivating and effective means of improving performance. Further development of the way in which wheelchair movement is controlled and simulated represents a key element in this multi stage project.

  1. The Effect of Transport Accessibility on the Social Inclusion of Wheelchair Users: A Mixed Method Analysis

    Directory of Open Access Journals (Sweden)

    Raquel Velho

    2016-06-01

    Full Text Available In recent years the accessibility of London buses has improved with the introduction of ramps and wheelchair priority areas. These advances are meant to remove physical barriers to entering the bus, but new conflicts have arisen particularly over the physical space aboard. We aimed to research the barriers faced by wheelchair users in public transport using a mixed methods approach to establish the breadth of issues faced by wheelchair users. To this end we quantified the push-force used alight a bus and a study to understand the coping mechanisms used by people to propel up a ramp. This quantitative approach found push forces which resulted in a load of 2 to 3 times body weight being transferred through people’s shoulders, forces which can be directly linked to shoulder injury. This could disable the user further, preventing them from being able to push their wheelchair. Alongside the quantitative study, we conducted qualitative research comprising of a number of in-depth interviews with wheelchair users about the barriers they face in public transport. Our main claim, highlighted through this interdisciplinary collaboration, is that proposed ‘solutions’ to accessibility, such as ramps, often generate problems of their own. These barriers can affect the life of wheelchair users, impacting on their confidence and causing social isolation. These can be long-term in nature or immediate.

  2. Design of an Automatic Path Finding Wheelchair with Intelligent Guidance System

    Directory of Open Access Journals (Sweden)

    Apratim MAJUMDER

    2011-03-01

    Full Text Available A conventional motorized wheelchair has been fitted with sensors and programmed with an intelligent guidance system to efficiently maneuver itself automatically from one point to another in a facility equipped with a grid of sensors that provide the wheelchair with the basic map of its course. The device described in this paper has been conceptualized such that once the wheelchair is given information regarding the starting and stopping point in a controlled facility, the wheelchair with this pre programmed information can efficiently construct a path towards its destination and automatically drive to that point from its present position while avoiding obstacles in its path and negotiating any turns and bends that it encounters in its course. This is achieved by means of sensors (IR and sonic located at strategic points on the chair, circuits that control the speed of the motors, and a set of microcontrollers programmed to execute the different functions of the wheelchair. The facility in which the wheelchair works has been fitted with a set of sensors that form the basis of the network which is used by the program governing the wheelchair’s automated movement to provide guidance to it by means of a course map.

  3. The Functional Classification and Field Test Performance in Wheelchair Basketball Players.

    Science.gov (United States)

    Gil, Susana María; Yanci, Javier; Otero, Montserrat; Olasagasti, Jurgi; Badiola, Aduna; Bidaurrazaga-Letona, Iraia; Iturricastillo, Aitor; Granados, Cristina

    2015-06-27

    Wheelchair basketball players are classified in four classes based on the International Wheelchair Basketball Federation (IWBF) system of competition. Thus, the aim of the study was to ascertain if the IWBF classification, the type of injury and the wheelchair experience were related to different performance field-based tests. Thirteen basketball players undertook anthropometric measurements and performance tests (hand dynamometry, 5 m and 20 m sprints, 5 m and 20 m sprints with a ball, a T-test, a Pick-up test, a modified 10 m Yo-Yo intermittent recovery test, a maximal pass and a medicine ball throw). The IWBF class was correlated (pbasketball. Therefore, in this team the correlations of the performance variables differed when they were related to the disability class, the years of dependence on the wheelchair and the experience in playing wheelchair basketball. These results should be taken into account by the technical staff and coaches of the teams when assessing performance of wheelchair basketball players.

  4. Robust Bio-Signal Based Control of an Intelligent Wheelchair

    Directory of Open Access Journals (Sweden)

    Dongyi Chen

    2013-09-01

    Full Text Available In this paper, an adaptive human-machine interaction (HMI method that is based on surface electromyography (sEMG signals is proposed for the hands-free control of an intelligent wheelchair. sEMG signals generated by the facial movements are obtained by a convenient dry electrodes sensing device. After the signals features are extracted from the autoregressive model, control data samples are updated and trained by an incremental online learning algorithm in real-time. Experimental results show that the proposed method can significantly improve the classification accuracy and training speed. Moreover, this method can effectively reduce the influence of muscle fatigue during a long time operation of sEMG-based HMI.

  5. Sprint, agility, strength and endurance capacity in wheelchair basketball players

    Science.gov (United States)

    Granados, C; Otero, M; Badiola, A; Olasagasti, J; Bidaurrazaga-Letona, I; Iturricastillo, A; Gil, SM

    2014-01-01

    The aims of the present study were, firstly, to determine the reliability and reproducibility of an agility T-test and Yo-Yo 10 m recovery test; and secondly, to analyse the physical characteristics measured by sprint, agility, strength and endurance field tests in wheelchair basketball (WB) players. 16 WB players (33.06 ± 7.36 years, 71.89 ± 21.71 kg and sitting body height 86.07 ± 6.82 cm) belonging to the national WB league participated in this study. Wheelchair sprint (5 and 20 m without ball, and 5 and 20 m with ball) agility (T-test and pick-up test) strength (handgrip and maximal pass) and endurance (Yo-Yo 10 m recovery test) were performed. T-test and Yo-Yo 10 m recovery test showed good reproducibility values (intraclass correlation coefficient, ICC = 0.74-0.94). The WB players’ results in 5 and 20 m sprints without a ball were 1.87 ± 0.21 s and 5.70 ± 0.43 s and with a ball 2.10 ± 0.30 s and 6.59 ± 0.61 s, being better than those reported in the literature. Regarding the pick-up test results (16.05 ± 0.52 s) and maximal pass (8.39 ± 1.77 m), players showed worse values than those obtained in elite players. The main contribution of the present study is the characterization of the physical performance profile of WB players using a field test battery. Furthermore, we demonstrated that the agility T-test and the aerobic Yo-Yo 10 m recovery test are reliable; consequently they may be appropriate instruments for measuring physical fitness in WB. PMID:25729153

  6. Fluid and sodium balance of elite wheelchair rugby players.

    Science.gov (United States)

    Black, Katherine Elizabeth; Huxford, Jody; Perry, Tracy; Brown, Rachel Clare

    2013-04-01

    Blood sodium concentration of tetraplegics during exercise has not been investigated. This study aimed to measure blood sodium changes in relation to fluid intakes and thermal comfort in tetraplegics during wheelchair rugby training. Twelve international male wheelchair rugby players volunteered, and measures were taken during 2 training sessions. Body mass, blood sodium concentration, and subjective thermal comfort using a 10-point scale were recorded before and after both training sessions. Fluid intake and the distance covered were measured during both sessions. The mean (SD) percentage changes in body mass during the morning and afternoon training sessions were +0.4%1 (0.65%) and +0.69% (1.24%), respectively. There was a tendency for fluid intake rate to be correlated with the percentage change in blood sodium concentration (p = .072, r2 = .642) during the morning training session; this correlation reached significance during the afternoon session (p = .004, r2 = .717). Fluid intake was significantly correlated to change in thermal comfort in the morning session (p = .018, r2 = .533), with this correlation showing a tendency in the afternoon session (p = .066, r2 = .151). This is the first study to investigate blood sodium concentrations in a group of tetraplegics. Over the day, blood sodium concentrations significantly declined; 2 players recorded blood sodium concentrations of 135 mmol/L, and 5 recorded blood sodium concentrations of 136 mmol/L. Excessive fluid intake as a means of attenuating thermal discomfort seems to be the primary cause of low blood sodium concentrations in tetraplegic athletes. Findings from this study could aid in the design of fluid-intake strategies for tetraplegics.

  7. Echocardiographic evaluation of wheelchair-bound basketball players.

    Science.gov (United States)

    Karagoz, Tevfik; Ozer, Sema; Bayrakci, Volga; Ergun, Nevin

    2003-08-01

    Cardiopulmonary function in sedentary men whose lower limbs have been immobilized for years has been shown to be markedly lower than normal. However, the cardiopulmonary function of paraplegics who regularly activate their upper limps and trunk has been suggested to be almost normal in a few studies. The purpose of the present study was to evaluate the left ventricular dimensions, left ventricular mass, systolic and diastolic function in adolescent wheelchair-bound basketball players using echocardio-graphy, and to compare the results with those of sedentary adolescents unable to use their lower extremities and the results of able bodied controls. The study group consisted of 22 male adolescent high school students who were unable to use their lower extremities: 11 were members of a high school basketball team who had been regularly playing basketball for at least 2 years, and 11 were sedentary adolescents none of whom was engaged in any kind of routine training program. The control group consisted of 11 healthy able-bodied male adolescents of similar age. There were no significant differences in left ventricular dimensions and wall thickness, aortic root, left atrium diameters, or left ventricular filling characteristics between the three groups. Wheelchair-bound basketball players had increased left ventricular ejection fraction and shortening fraction compared with the sedentary unable-bodied individuals. Although left ventricular ejection fractions were significantly lower than in normal adolescents, all ejection fraction values except one were within the normal limits in the unable-bodied basketball players. The results of the present study suggest that an upper extremity exercise program and sports such as basketball can improve the cardiac functions and additional echocardiographic functions of people unable to use their lower extremities, potentially to normal levels.

  8. Sprint, agility, strength and endurance capacity in wheelchair basketball players.

    Science.gov (United States)

    Yanci, J; Granados, C; Otero, M; Badiola, A; Olasagasti, J; Bidaurrazaga-Letona, I; Iturricastillo, A; Gil, Sm

    2015-03-01

    The aims of the present study were, firstly, to determine the reliability and reproducibility of an agility T-test and Yo-Yo 10 m recovery test; and secondly, to analyse the physical characteristics measured by sprint, agility, strength and endurance field tests in wheelchair basketball (WB) players. 16 WB players (33.06 ± 7.36 years, 71.89 ± 21.71 kg and sitting body height 86.07 ± 6.82 cm) belonging to the national WB league participated in this study. Wheelchair sprint (5 and 20 m without ball, and 5 and 20 m with ball) agility (T-test and pick-up test) strength (handgrip and maximal pass) and endurance (Yo-Yo 10 m recovery test) were performed. T-test and Yo-Yo 10 m recovery test showed good reproducibility values (intraclass correlation coefficient, ICC = 0.74-0.94). The WB players' results in 5 and 20 m sprints without a ball were 1.87 ± 0.21 s and 5.70 ± 0.43 s and with a ball 2.10 ± 0.30 s and 6.59 ± 0.61 s, being better than those reported in the literature. Regarding the pick-up test results (16.05 ± 0.52 s) and maximal pass (8.39 ± 1.77 m), players showed worse values than those obtained in elite players. The main contribution of the present study is the characterization of the physical performance profile of WB players using a field test battery. Furthermore, we demonstrated that the agility T-test and the aerobic Yo-Yo 10 m recovery test are reliable; consequently they may be appropriate instruments for measuring physical fitness in WB.

  9. Sprint, agility, strength and endurance capacity in wheelchair basketball players

    Directory of Open Access Journals (Sweden)

    Javier Yanci

    2014-11-01

    Full Text Available The aims of the present study were, firstly, to determine the reliability and reproducibility of an agility T-test and Yo-Yo 10 m recovery test; and secondly, to analyse the physical characteristics measured by sprint, agility, strength and endurance field tests in wheelchair basketball (WB players. 16 WB players (33.06 ± 7.36 years, 71.89 ± 21.71 kg and sitting body height 86.07 ± 6.82 cm belonging to the national WB league participated in this study. Wheelchair sprint (5 and 20 m without ball, and 5 and 20 m with ball agility (T-test and pick-up test strength (handgrip and maximal pass and endurance (Yo-Yo 10 m recovery test were performed. T-test and Yo-Yo 10 m recovery test showed good reproducibility values (intraclass correlation coefficient, ICC = 0.74-0.94. The WB players’ results in 5 and 20 m sprints without a ball were 1.87 ± 0.21 s and 5.70 ± 0.43 s and with a ball 2.10 ± 0.30 s and 6.59 ± 0.61 s, being better than those reported in the literature. Regarding the pick-up test results (16.05 ± 0.52 s and maximal pass (8.39 ± 1.77 m, players showed worse values than those obtained in elite players. The main contribution of the present study is the characterization of the physical performance profile of WB players using a field test battery. Furthermore, we demonstrated that the agility T-test and the aerobic Yo-Yo 10 m recovery test are reliable; consequently they may be appropriate instruments for measuring physical fitness in WB.

  10. Physiological and perceptual effects of precooling in wheelchair basketball athletes.

    Science.gov (United States)

    Forsyth, Peta; Pumpa, Kate; Knight, Emma; Miller, Joanna

    2016-11-01

    To investigate the physiological and perceptual effects of three precooling strategies during pre-exercise rest in athletes with a spinal cord injury (SCI). Randomized, counterbalanced. Participants were precooled, then rested for 60 minutes (22.7 ± 0.2°C, 64.2 ± 2.6%RH). National Wheelchair Basketball Training Centre, Australia. Sixteen wheelchair basketball athletes with a SCI. Participants were precooled through; 1) 10 minutes of 15.8°C cold water immersion (CWI), 2) ingestion of 6.8 g/kg-1 of slushie (S) from sports drink; 3) ingestion of 6.8 g/kg-1 of slushie with application of iced towels to the legs, torso and back/arms (ST); or 4) ingestion of 6.8 g/kg-1 of room temperature (22.3°C) sports drink (CON). Core temperature (Tgi), skin temperature (Tsk), heart rate (HR), and thermal and gastrointestinal comfort. Following CWI, a significant reduction in Tgi was observed compared to CON, with a greatest reduction of 1.58°C occurring 40 minutes post-cooling (95% CI [1.07, 2.10]). A significant reduction in Tgi following ST compared to CON was also observed at 20 minutes (0.56°C; [0.03, 1.09]) and 30 minutes (0.56°C; [0.04, 1.09]) post-cooling. Additionally, a significant interaction between impairment level and time was observed for Tgi and HR, demonstrating athletes with a higher level of impairment experienced a greater reduction in HR and significant decrease in rate of decline in Tgi, compared to lesser impaired athletes. CWI and ST can effectively lower body temperature in athletes with a SCI, and may assist in tolerating warm conditions.

  11. Circulating Progenitor Cell Response to Exercise in Wheelchair Racing Athletes.

    Science.gov (United States)

    Niemiro, Grace M; Edwards, Thomas; Barfield, J P; Beals, Joseph W; Broad, Elizabeth M; Motl, Robert W; Burd, Nicholas A; Pilutti, Lara A; De Lisio, Michael

    2017-08-11

    Circulating progenitor cells (CPCs) are a heterogeneous population of stem/progenitor cells in peripheral blood that participate in tissue repair. CPC mobilization has been well characterized in able-bodied persons, but has not been previously investigated in wheelchair racing athletes. The purpose of this study was to characterize CPC and CPC sub-population mobilization in elite wheelchair racing athletes in response to acute, upper-extremity aerobic exercise to determine if CPC responses are similar to ambulatory populations. Eight participants (3 female; age=27.5±4.0 years; supine height=162.5±18.6cm; weight=53.5±10.9kg, VO2peak=2.4±0.62 L/min; years post injury=21.5±6.2 years) completed a 25 km time trial on a road course. Blood sampling occurred before (Pre) and immediately post (Post) exercise for quantification of CPCs (CD34), HSPCs (CD34/CD45), HSCs (CD34/CD45/CD38), CD34 adipose tissue-derived (AT)-MSCs (CD45/CD34/CD105/CD31), CD34 bone marrow-derived (BM)-MSCs (CD45/CD34/CD105/CD31), and EPCs (CD45/CD34/VEGFR2) via flow cytometry. Blood lactate was measured Pre- and Post-trial as an indicator of exercise intensity. CPC concentration increased 5.7 fold post-exercise (P=0.10). HSPCs, HSCs, EPCs, and both MSC populations were not increased post exercise. Baseline HSPCs were significantly positively correlated to absolute VO2peak (Rho = 0.71, Pracing athletes is related to cardiorespiratory fitness and responses to exercise are positively related to exercise intensity.

  12. The influence of simulated rotator cuff tears on the risk for impingement in handbike and handrim wheelchair propulsion

    NARCIS (Netherlands)

    van Drongelen, S.; Schlussel, M.; Arnet, U.; Veeger, H.E.J.

    2013-01-01

    Background: Rotator cuff tears strongly affect the biomechanics of the shoulder joint in their role to regulate the joint contact force needed to prevent the joint from dislocation. The aim of this study was to investigate the influence of simulated progressed rotator cuff tears on the (in)stability

  13. Exotic propulsion systems - A space exploration imperative

    Science.gov (United States)

    Haloulakos, V. E.

    1992-07-01

    Treatment is given to the need for and use of unusual propulsion systems in the forthcoming development of space vehicles. The requirements of lunar and Martian outposts are set forth, and the expected delta velocities, vehicle masses, and specific energy levels are listed. Exotic propulsion systems are considered that can provide the specific impulse levels needed for the scenarios discussed. Discussed are antimatter propulsion, teleportation, and antigravity machines, and the theoretical and practical implications of their development and use are mentioned. The use of antiprotons in medical treatment and materials processing is explained and extended to the propulsion application. The paper demonstrates the potential of exotic propulsion systems to contribute to space exploration.

  14. Evaluation of an intelligent wheelchair system for older adults with cognitive impairments

    Science.gov (United States)

    2013-01-01

    Background Older adults are the most prevalent wheelchair users in Canada. Yet, cognitive impairments may prevent an older adult from being allowed to use a powered wheelchair due to safety and usability concerns. To address this issue, an add-on Intelligent Wheelchair System (IWS) was developed to help older adults with cognitive impairments drive a powered wheelchair safely and effectively. When attached to a powered wheelchair, the IWS adds a vision-based anti-collision feature that prevents the wheelchair from hitting obstacles and a navigation assistance feature that plays audio prompts to help users manoeuvre around obstacles. Methods A two stage evaluation was conducted to test the efficacy of the IWS. Stage One: Environment of Use – the IWS’s anti-collision and navigation features were evaluated against objects found in a long-term care facility. Six different collision scenarios (wall, walker, cane, no object, moving and stationary person) and three different navigation scenarios (object on left, object on right, and no object) were performed. Signal detection theory was used to categorize the response of the system in each scenario. Stage Two: User Trials – single-subject research design was used to evaluate the impact of the IWS on older adults with cognitive impairment. Participants were asked to drive a powered wheelchair through a structured obstacle course in two phases: 1) with the IWS and 2) without the IWS. Measurements of safety and usability were taken and compared between the two phases. Visual analysis and phase averages were used to analyze the single-subject data. Results Stage One: The IWS performed correctly for all environmental anti-collision and navigation scenarios. Stage Two: Two participants completed the trials. The IWS was able to limit the number of collisions that occurred with a powered wheelchair and lower the perceived workload for driving a powered wheelchair. However, the objective performance (time to complete course

  15. NASA Glenn Research Center's Hypersonic Propulsion Program

    Science.gov (United States)

    Palac, Donald T.

    1999-01-01

    NASA Glenn Research Center (GRC), as NASA's lead center for aeropropulsion, is responding to the challenge of reducing the cost of space transportation through the integration of air-breathing propulsion into launch vehicles. Air- breathing launch vehicle (ABLV) propulsion requires a marked departure from traditional propulsion applications. and stretches the technology of both rocket and air-breathing propulsion. In addition, the demands of the space launch mission require an unprecedented level of integration of propulsion and vehicle systems. GRC is responding with a program with rocket-based combined cycle (RBCC) propulsion technology as its main focus. RBCC offers the potential for simplicity, robustness, and performance that may enable low-cost single-stage-to-orbit (SSTO) transportation. Other technologies, notably turbine-based combined cycle (TBCC) propulsion, offer benefits such as increased robustness and greater mission flexibility, and are being advanced, at a slower pace, as part of GRC's program in hypersonics.

  16. Magnetic levitation and MHD propulsion

    Science.gov (United States)

    Tixador, P.

    1994-04-01

    Magnetic levitation and MHD propulsion are now attracting attention in several countries. Different superconducting MagLev and MHD systems will be described concentrating on, above all, the electromagnetic aspect. Some programmes occurring throughout the world will be described. Magnetic levitated trains could be the new high speed transportation system for the 21st century. Intensive studies involving MagLev trains using superconductivity have been carried out in Japan since 1970. The construction of a 43 km long track is to be the next step. In 1991 a six year programme was launched in the United States to evaluate the performances of MagLev systems for transportation. The MHD (MagnetoHydroDynamic) offers some interesting advantages (efficiency, stealth characteristics, ...) for naval propulsion and increasing attention is being paid towards it nowadays. Japan is also up at the top with the tests of Yamato I, a 260 ton MHD propulsed ship. Depuis quelques années nous assistons à un redémarrage de programmes concernant la lévitation et la propulsion supraconductrices. Différents systèmes supraconducteurs de lévitation et de propulsion seront décrits en examinant plus particulièrement l'aspect électromagnétique. Quelques programmes à travers le monde seront abordés. Les trains à sustentation magnétique pourraient constituer un nouveau mode de transport terrestre à vitesse élevée (500 km/h) pour le 21^e siècle. Les japonais n'ont cessé de s'intéresser à ce système avec bobine supraconductrice. Ils envisagent un stade préindustriel avec la construction d'une ligne de 43 km. En 1991 un programme américain pour une durée de six ans a été lancé pour évaluer les performances des systèmes à lévitation pour le transport aux Etats Unis. La MHD (Magnéto- Hydro-Dynamique) présente des avantages intéressants pour la propulsion navale et un regain d'intérêt apparaît à l'heure actuelle. Le japon se situe là encore à la pointe des d

  17. OTV propulsion tecnology programmatic overview

    Science.gov (United States)

    Cooper, L. P.

    1984-04-01

    An advanced orbit transfer vehicles (OTV) which will be an integral part of the national space transportation system to carry men and cargo between low Earth orbit and geosynchronous orbit will perform planetary transfers and deliver large acceleration limited space structures to high Earth orbits is reviewed. The establishment of an advanced propulsion technology base for an OTV for the mid 1990's is outlined. The program supports technology for three unique engine concepts. Work is conducted to generic technologies which benefit all three concepts and specific technology which benefits only one of the concepts. Concept and technology definitions to identify propulsion innovations, and subcomponent research to explore and validate their potential benefits are included.

  18. NASA's laser-propulsion project

    Science.gov (United States)

    Jones, L. W.; Keefer, D. R.

    1982-01-01

    Design concepts, study results, and research directions toward development of CW laser heating of remotely flying spacecraft fuels to provide high impulse thrust are presented. The incident laser radiation would be absorbed by hydrogen through a medium of a laser-supported plasma. The laser energy could be furnished from an orbiting solar-powered laser platform and used to drive the engines of an orbital transfer vehicle (OTV) at costs less than with a chemical propulsion system. The OTV propulsion chamber would be reduced in size comparable to the volume addition of the incident laser energy absorber. The temperatures in the hydrogen-fueled system could reach 5000-15,000 K, and studies have been done to examine the feasibility of ion-electron recombination. Kinetic performance, temperature field, and power necessary to sustain a laser thrust augmented system modeling results are discussed, along with near-term 30 kW CO2 laser system tests.

  19. Transatospheric laser propulsion: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Myrabo, L.N.

    1988-08-15

    The detailed description and performance analysis of a 1.4 meter diameter Lightcraft Technology Demonstrator (LTD) is presented. The novel launch system employs a 100 MW-class ground-based laser to transmit power directly to an advanced combined-cycle engine that propels the 120 kg LTD to orbit -- with a mass ratio of two. The single-stage-to-orbit (SSTO) LTD machine then becomes an autonomous sensor satellite that can deliver precise, high quality information typical of today's large orbital platforms. The dominant motivation behind this study is to provide an example of how laser propulsion and its low launch costs can induce a comparable order-of-magnitude reduction in sensor satellite packaging costs. The issue is simply one of production technology for future, survivable SSTO aerospace vehicles that intimately share both laser propulsion engine and satellite functional hardware. 12 refs., 31 figs.

  20. Electrodynamic Tethers for Spacecraft Propulsion

    Science.gov (United States)

    Johnson, Les; Estes, Robert D.; Lorenzini, Enrico; Martinez-Sanchez, Manuel; Sanmartin, Juan; Vas, Irwin

    1998-01-01

    Relatively short electrodynamic tethers can use solar power to 'push' against a planetary magnetic field to achieve propulsion without the expenditure of propellant. The groundwork has been laid for this type of propulsion. NASA began developing tether technology for space applications in the 1960's. Important recent milestones include retrieval of a tether in space (TSS-1, 1992), successful deployment of a 20-km-long tether in space (SEDS-1, 1993), and operation of an electrodynamic tether with tether current driven in both directions-power and thrust modes (PMG, 1993). The planned Propulsive Small Expendable Deployer System (ProSEDS) experiment will demonstrate electrodynamic tether thrust during its flight in early 2000. ProSEDS will use the flight-proven Small Expendable Deployer System (SEDS) to deploy a 5 km bare copper tether from a Delta II upper stage to achieve approximately 0.4 N drag thrust, thus deorbiting the stage. The experiment will use a predominantly 'bare' tether for current collection in lieu of the endmass collector and insulated tether approach used on previous missions. Theory and ground-based plasma chamber testing indicate that the bare tether is a highly-efficient current collector. The flight experiment is a precursor to utilization of the technology on the International Space Station for reboost application and the more ambitious electrodynamic tether upper stage demonstration mission which will be capable of orbit raising, lowering and inclination changes - all using electrodynamic thrust. In addition, the use of this type of propulsion may be attractive for future missions at Jupiter and any other planetary body with a magnetosphere.

  1. Pure Nuclear Fusion Bomb Propulsion

    OpenAIRE

    Winterberg, F.

    2008-01-01

    Recent progress towards the non-fission ignition of thermonuclear micro-explosions raises the prospect for a revival of the nuclear bomb propulsion idea, both for the fast transport of large payloads within the solar system and the launch into earth orbit without the release of fission products into the atmosphere. To reach this goal three areas of research are of importance: 1)Compact thermonuclear ignition drivers. 2)Fast ignition and deuterium burn. 3)Space-craft architecture involving mag...

  2. Laser Diagnostics for Spacecraft Propulsion

    Science.gov (United States)

    2015-10-13

    Absorption Spectroscopy (DLAS) – Wavelength Modulation Spectroscopy (WMS) • Arcjets • Hall thrusters/Ion engines – Laser Induced Fluorescence (LIF) – Time...technologies • Tunable diode lasers developed in the 1960s – Diagnostic techniques have been developed alongside propulsion technologies – Simulation of space...post-test – Cut open thruster to examine catalyst • Diode Laser Absorption Spectroscopy – Non-intrusive, in-situ measurements – Temperature, species

  3. Nuclear Thermal Propulsion Development Risks

    Science.gov (United States)

    Kim, Tony

    2015-01-01

    There are clear advantages of development of a Nuclear Thermal Propulsion (NTP) for a crewed mission to Mars. NTP for in-space propulsion enables more ambitious space missions by providing high thrust at high specific impulse ((is) approximately 900 sec) that is 2 times the best theoretical performance possible for chemical rockets. Missions can be optimized for maximum payload capability to take more payload with reduced total mass to orbit; saving cost on reduction of the number of launch vehicles needed. Or missions can be optimized to minimize trip time significantly to reduce the deep space radiation exposure to the crew. NTR propulsion technology is a game changer for space exploration to Mars and beyond. However, 'NUCLEAR' is a word that is feared and vilified by some groups and the hostility towards development of any nuclear systems can meet great opposition by the public as well as from national leaders and people in authority. The public often associates the 'nuclear' word with weapons of mass destruction. The development NTP is at risk due to unwarranted public fears and clear honest communication of nuclear safety will be critical to the success of the development of the NTP technology. Reducing cost to NTP development is critical to its acceptance and funding. In the past, highly inflated cost estimates of a full-scale development nuclear engine due to Category I nuclear security requirements and costly regulatory requirements have put the NTP technology as a low priority. Innovative approaches utilizing low enriched uranium (LEU). Even though NTP can be a small source of radiation to the crew, NTP can facilitate significant reduction of crew exposure to solar and cosmic radiation by reducing trip times by 3-4 months. Current Human Mars Mission (HMM) trajectories with conventional propulsion systems and fuel-efficient transfer orbits exceed astronaut radiation exposure limits. Utilizing extra propellant from one additional SLS launch and available

  4. A systematic review of wheelchair skills tests for manual wheelchair users with a spinal cord injury : towards a standardized outcome measure

    NARCIS (Netherlands)

    Fliess-Douer, Osnat; Vanlandewijck, Yves C.; Manor, Galia Lubel; Van Der Woude, Lucas H. V.

    2010-01-01

    Objective: To review, analyse, evaluate and critically appraise available wheelchair skill tests in the international literature and to determine the need for a standardized measurement tool of manual wheeled mobility in those with spinal cord injury. Data sources: A systematic review of literature

  5. Self-Talk in Wheelchair Basketball: The Effects of an Intervention Program on Dribbling and Passing Performance

    Science.gov (United States)

    Harbalis, Thomas; Hatzigeorgiadis, Antonis; Theodorakis, Yannis

    2008-01-01

    The purpose of this study was to examine the effectiveness of a self-talk intervention program on performance of wheelchair basketball drills. Twenty-two (N = 22) wheelchair basketball athletes from two different clubs of the same league participated in the study. The duration of the intervention was 12 weeks and its aim was the improvement of two…

  6. Effect of push handle height on net moments and forces on the musculoskeletal system during standardized wheelchair pushing tasks

    NARCIS (Netherlands)

    Van Der Woude, L H; Van Koningsbruggen, C M; Kroes, A L; Kingma, I

    1995-01-01

    The aim of this investigation was to analyze the external forces and biomechanical loading on the musculoskeletal system during wheelchair pushing, in relation to different push handle heights. In addition, recommendations for wheelchair pushing in accordance with push handle height are made. Eight

  7. 10-m shuttle ride test in youth with osteogenesis imperfecta who use wheelchairs : Feasibility, reproducibility, and physiological responses

    NARCIS (Netherlands)

    Bongers, Bart C.; Rijks, Ester B G; Harsevoort, Arjan G J; Takken, Tim|info:eu-repo/dai/nl/184586674; van Brussel, Marco|info:eu-repo/dai/nl/30481962X

    2016-01-01

    Background: Physical fitness levels in youth with osteogenesis imperfecta (OI) who use wheelchairs are unknown. The 10-m Shuttle Ride Test (SRiT) has recently been introduced as a field test to determine cardiorespiratory fitness in children with cerebral palsy who selfpropel a wheelchair.

  8. The profile of upper extremity muscular strength in female wheelchair basketball players: a pilot study.

    Science.gov (United States)

    Külünkoğlu, Bahar; Akkubak, Yasemin; Ergun, Nevin

    2017-02-14

    The purpose of this study was to analyze and compare the profile of upper extremity muscle strength in female wheelchair basketball players with that of sex-matched non-disabled controls. Nineteen female subjects were enrolled in this study. These were divided into two groups. Group 1 (n=10) consisted of wheelchair basketball players and Group 2 (n=9) of non-disabled individuals. Muscular strength in the shoulder was measured using an isokinetic dynamometer. Isometric and isotonic muscular endurance in the shoulder joint was evaluated in terms of the length of time subjects could hold a 5-kilogram dumbbell at 45 degrees and the number of abduction repetitions to 45 degrees with a 5-kilogram dumbbell in 30 seconds, respectively. Pinch strength and hand grip strength were measured using a Pinch gauge and hand dynamometer, respectively. Significant differences were observed between the groups in terms of all parameters of muscular strength in the shoulder joint, hand grip and pinch strength. Upper extremity muscular strength in female wheelchair basketball players was greater than in the non-disabled controls. We concluded that the difference in muscle strength between the groups mostly derived from using wheelchairs due to players' intense training and busy match schedules. Additionally, the profile of upper extremity muscle strength in female wheelchair basketball players in our study can be used as basic data for the introduction of exercise rehabilitation programs and as a guide for future research.

  9. Offensive tactical thinking level of wheelchair basketball players in Arab countries.

    Science.gov (United States)

    Hindawi, Omar S; Orabi, Samira; Al Arjan, Jafar; Judge, Lawrence W; Cottingham, Michael; Bellar, David Michael

    2013-01-01

    The purpose of this study was to assess the appropriateness of offensive tactical decision-making of Arab basketball players, and to determine if there are differences in the appropriateness of offensive tactical decision-making within the various disability classifications of Arab basketball players. A twenty-question survey was formulated to assess decision-making in offensive tactical situations in wheelchair basketball players. Participants in the present study were 108 athletes from 10 Arab national teams participating in wheelchair basketball. The mean offensive tactical thinking level of wheelchair basketball players in the 20 different situations in the Arab countries ranged between 1.38-2.84, and the standard deviations for these 20 means ranged from 0.41 to 0.90. The total mean of all tactical situations was 2.33, which is moderate thinking level. The influence of the disability classification on the offensive tactical thinking of wheelchair basketball players was addressed by examining the data via a one-way ANOVA. The ANOVA revealed no significant differences among disability classifications/categories in tactical thinking (F(3, 104)=1.12, p=0.34). This study represents the first attempt to identify why Arab nations have not consistently qualified for the Paralympics or World Championships. These findings indicate that the moderate offensive tactical thinking level of wheelchair basketball players on Arab national teams may be part of the reason that performances of these teams have not been as strong as they would like.

  10. The relationship between functional potential and field performance in elite female wheelchair basketball players.

    Science.gov (United States)

    Vanlandewijck, Yves C; Evaggelinou, Christina; Daly, Daniel J; Verellen, Joeri; Van Houtte, Siska; Aspeslagh, Vanessa; Hendrickx, Robby; Piessens, Tine; Zwakhoven, Bjorn

    2004-07-01

    The functional classification system for wheelchair basketball is based on an analysis of the players' functional resources through field-testing and game observation. Under this system, players are assigned a score of 1 to 4.5. The aim of this study was to determine if the wheelchair basketball player classification system reflects the existing differences in performance of elite female players. During the World Championship for Wheelchair Basketball in Sydney 1998, eight teams were videotaped for three 40-min games for a total of 120 min per team. Fifty-nine female players (Class I [1 and 1.5 points] n=12; Class II [2 and 2.5 points] n=20; Class III [3 and 3.5 points] n=13; Class IV [4 and 4.5 points] n=14) were retained for a detailed performance analysis by means of the Comprehensive Basketball Grading System (CBGS). Two-way analysis of variance showed high point players to perform better compared with low point players for the majority of variables determining the quality of game performance. A lack of significant differences between two adjacent classes was explained on the basis of the methodological approach, the class-position relationship in this sample, and the performance level of women's wheelchair basketball. We conclude that the performance of elite female wheelchair basketball players is dependent on functional ability.

  11. A survey of deep tissue injury in elite female wheelchair basketball players.

    Science.gov (United States)

    Shimizu, Yukiyo; Mutsuzaki, Hirotaka; Tachibana, Kaori; Tsunoda, Kenji; Hotta, Kazushi; Fukaya, Takashi; Ikeda, Eiji; Yamazaki, Masashi; Wadano, Yasuyoshi

    2017-01-01

    To investigate deep tissue injuries (DTIs) in elite female wheelchair basketball players and identify factors associated with their occurrence. Study participants were 22 female wheelchair basketball players on the Japanese national team. The sacral and bilateral ischial regions of each participant were examined using ultrasonography to detect DTIs. DTIs were found in 15 players (68.2%). DTIs were more frequent in players with a central nervous system disorder (CNSd) (85.7%) than in those with skeletal system disease (SSd) (37.5%, p = 0.020), and in players using a wheelchair in daily life (84.6%) than those using a wheelchair only for basketball (44.4%, p = 0.046). Players with pelvic instability were more likely to have DTIs (90.9% vs. 45.5%, p = 0.017). DTIs were deeper in the ischial region than the sacral region (p = 0.022). Players with CNSd had more DTIs in sacral regions (90% vs. 10%, p = 0.014). Players with DTIs had lower systolic blood pressure (sBP), red blood cell (RBC) count, and serum creatinine levels (sCr) (all p wheelchair use in daily life, pelvic instability, and lower sBP, RBC, and sCr increased the risk of DTIs.

  12. Wireless biomedical signal monitoring device on wheelchair using noncontact electro-mechanical film sensor.

    Science.gov (United States)

    Kim, Jong-Myoung; Hong, Joo-Hyun; Cho, Myeong-Chan; Cha, Eun-Jong; Lee, Tae-Soo

    2007-01-01

    The present study purposed to measure the BCG (Ballistocardiogram) of subjects on a wheelchair using a noncontact electro-mechanical film sensor (EMFi sensor) and detect the respiratory rate from BCG in real-time while the subjects are moving. In order to measure wirelessly the BCG of subjects moving on a wheelchair, we made a seat-type noncontact EMFi sensor and developed a transmitter and a receiver using Zigbee wireless RF communication technology. The sensor is embedded with a 3-axis accelerometer to remove the noise of wheelchair vibration from BCG signal. Signal obtained from each sensor goes through the A/D converter and is recorded in the SD (Secure Digital) card in PDA (Personal Digital Assistance) with a receiving part. We also developed a PC (Personal Computer) data analysis program, analyzed data recorded in the SD card using the program, and presented the results in graph. Lastly, this study demonstrated that a warning message can be sent from PDA to the remote server via a CDMA (Code Division Multiple Access) network in case the person on wheelchair falls in emergency. Our experiment was carried out with healthy male and female adults in their 20s who volunteered to help this research. The results of analyzing collected data will show that the respiratory rate can be measured in real-time on a moving wheelchair.

  13. Integrated modeling and design for realizing a two-wheeled wheelchair for disabled.

    Science.gov (United States)

    Altalmas, Tareq; Aula, Abqori; Ahmad, Salmiah; Tokhi, M O; Akmeliawati, Rini

    2016-01-01

    Two-wheeled wheelchairs are considered highly nonlinear and complex systems. The systems mimic a double-inverted pendulum scenario and will provide better maneuverability in confined spaces and also to reach higher level of height for pick and place tasks. The challenge resides in modeling and control of the two-wheeled wheelchair to perform comparably to a normal four-wheeled wheelchair. Most common modeling techniques have been accomplished by researchers utilizing the basic Newton's Laws of motion and some have used 3D tools to model the system where the models are much more theoretical and quite far from the practical implementation. This article is aimed at closing the gap between the conventional mathematical modeling approaches where the integrated 3D modeling approach with validation on the actual hardware implementation was conducted. To achieve this, both nonlinear and a linearized model in terms of state space model were obtained from the mathematical model of the system for analysis and, thereafter, a 3D virtual prototype of the wheelchair was developed, simulated, and analyzed. This has increased the confidence level for the proposed platform and facilitated the actual hardware implementation of the two-wheeled wheelchair. Results show that the prototype developed and tested has successfully worked within the specific requirements established.

  14. Evaluation on an ergonomic design of functional clothing for wheelchair users.

    Science.gov (United States)

    Wang, Yunyi; Wu, Daiwei; Zhao, Mengmeng; Li, Jun

    2014-05-01

    Researchers have pointed out that people with physical disabilities find it difficult to obtain suitable clothing. In this study a set of wheelchair user oriented functional clothing was designed. Attention was paid to the wheelchair users' daily living activities related with clothing. An evaluating system combined with sports tournament and rehabilitation medicine was introduced to assess the new designed clothing. Six wheelchair users (3 males and 3 females) were invited to wear the clothing. A set of normal functional clothing was employed as a comparison (Control). The time required to complete three different daily living activities, i.e. dressing and undressing, going to toilet and bathing were recorded. Results showed that with the new clothing wheelchair users' competence of managing toilet was increased by 52.9%. The time needed for toilet was reduced by 45.7%. Their capability of managing dressing and undressing was improved by 24.6%. The study indicated that the newly designed clothing could facilitate wheelchair users' daily living activities related with clothing. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  15. The Innovative Design and Prototype Verification of Wheelchair with One Degree of Freedom to Perform Lifting and Standing Functions

    Science.gov (United States)

    Hsieh, Long-Chang; Chen, Tzu-Hsia

    2017-12-01

    Traditionally, the mechanism of wheelchair with lifting and standing functions has 2 degrees of freedom, and used 2 power sources to perform these 2 motion function. The purpose of this paper is to invent new wheelchair with 1 degree of freedom to perform these 2 motion functions. Hence, we can use only 1 power source to drive the mechanism to achieve lifting and standing motion functions. The new design has the advantages of simple operation, more stability, and more safety. For traditional standing wheelchair, its’ centre of gravity moves forward when standing up and it needs 2 auxiliary wheels to prevent dumping. In this paper, by using the checklist method of Osborn, the wheelchair with 1 DOF is invented to perform lifting and standing functions. The centre of gravity of this new wheelchair after standing up still located between the front and rear wheels, no auxiliary wheels needed. Finally, the prototype is manufactured to verify the theoretical results.

  16. Powered Flight The Engineering of Aerospace Propulsion

    CERN Document Server

    Greatrix, David R

    2012-01-01

    Whilst most contemporary books in the aerospace propulsion field are dedicated primarily to gas turbine engines, there is often little or no coverage of other propulsion systems and devices such as propeller and helicopter rotors or detailed attention to rocket engines. By taking a wider viewpoint, Powered Flight - The Engineering of Aerospace Propulsion aims to provide a broader context, allowing observations and comparisons to be made across systems that are overlooked by focusing on a single aspect alone. The physics and history of aerospace propulsion are built on step-by-step, coupled with the development of an appreciation for the mathematics involved in the science and engineering of propulsion. Combining the author’s experience as a researcher, an industry professional and a lecturer in graduate and undergraduate aerospace engineering, Powered Flight - The Engineering of Aerospace Propulsion covers its subject matter both theoretically and with an awareness of the practicalities of the industry. To ...

  17. Influence of wheelchair front caster wheel on reverse directional stability.

    Science.gov (United States)

    Guo, Songfeng; Cooper, Rory A; Corfman, Tom; Ding, Dan; Grindle, Garrett

    2003-01-01

    The purpose of this research was to study directional stability during reversing of rear-wheel drive, electric powered wheelchairs (EPW) under different initial front caster orientations. Specifically, the weight distribution differences caused by certain initial caster orientations were examined as a possible mechanism for causing directional instability that could lead to accidents. Directional stability was quantified by measuring the drive direction error of the EPW by a motion analysis system. The ground reaction forces were collected to determine the load on the front casters, as well as back-emf data to attain the speed of the motors. The drive direction error was found to be different for various initial caster orientations. Drive direction error was greatest when both casters were oriented 90 degrees to the left or right, and least when both casters were oriented forward. The results show that drive direction error corresponds to the loading difference on the casters. The data indicates that loading differences may cause asymmetric drag on the casters, which in turn causes unbalanced torque load on the motors. This leads to a difference in motor speed and drive direction error.

  18. An especial skill in elite wheelchair basketball players.

    Science.gov (United States)

    Fay, K; Breslin, G; Czyż, S H; Pizlo, Z

    2013-08-01

    We aimed to investigate whether an especial skill is present in elite wheelchair basketball players when taking twenty shots with a regular basketball from five different distances (11 ft, 13 ft, 17 ft, & 19 ft) from the basket including the free throw line (15 ft). Twelve elite male basketball players participated. The results showed that as distance increased shot accuracy decreased in line with force by variability predictions for the 11 ft, 13 ft, 17 ft, & 19 ft distances. However, shot performance at the free throw line where players are more familiar with practicing free throw shots did not follow this trend. A linear regression line was drawn to predict performance at the free throw line based on nearer (11 ft & 13 ft) and farer (17 ft & 19 ft) distances to the basket, this was then compared to actual performance. A significant difference between actual and predicted scores was found (p<.05) supporting the presence of an especial skill. Significant positive correlations were found for the 11 ft and 17 ft distance, age, years of playing, and accumulated practice hours with performance at the 15 ft line (p<.05). These correlations imply the operation of generalization in the especial skill. This observation received support from applying a model in which shot accuracy as a function of distance was approximated by two regression lines. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Respiratory muscle strength and aerobic performance of wheelchair basketball players

    Directory of Open Access Journals (Sweden)

    Raphael N. Pereira

    Full Text Available Abstract The respiratory system has been described as a limiting factor in the performance of athletes. Therefore, the objective of this study was to evaluate the relationship between the respiratory muscle strength (RMS and aerobic performance of wheelchair basketball players (WCBPs. We evaluated 19 male WCBPs who were divided into two groups: trunk control group (TCG and without trunk control group (WTCG. All participants underwent a pulmonary function test, evaluation of maximal inspiratory (MIP and expiratory (MEP pressures, and an aerobic performance test. The MIP of both groups and the MEP values of TCG exceeded the predicted values for age and gender. No differences were observed in the MIP and aerobic performance between the groups although a difference was observed in the MEP values. Positive correlations were observed between MIP/MEP and the aerobic performance for both groups. These results suggested that the overall RMS of this group of WCBPs fell within or above the predicted values. Hence, the study concluded that RMS can positively influence the aerobic performance of WCBP.

  20. Trunk Function Correlates Positively with Wheelchair Basketball Player Classification.

    Science.gov (United States)

    Santos, Sileno da Silva; Krishnan, Chandramouli; Alonso, Angelica Castilho; Greve, Júlia Maria D'Andréa

    2017-02-01

    The aims of this study were (1) to identify differences in trunk muscle strength and balance among various classes of wheelchair basketball (WCB) players and (2) to determine if trunk muscle strength and balance correlate with the current observation-based classification of WCB players. Isometric trunk strength and balance (limits of stability) were objectively quantified in 42 male WCB players. Principal component analysis was used to synthesize a battery of strength and balance measures into a single, composite score of trunk function. The K-means clustering algorithm was then used to generate an objective classification system by stratifying players into 4 classes based on their trunk function. Results indicated that there were significant differences in trunk muscle strength and balance between various classes of WCB players (P < 0.05), such that the mean peak trunk extensor and flexor torque and limits of stability indices increased progressively according to the players' classes. There was also a significant correlation between observation-based WCB classification and principal component analysis cluster analysis-based WCB classification (ρ = 0.785, P < 0.05). This study provides novel evidence indicating that trunk strength and balance differ among various classes of WCB players, and objective measures of trunk function correlate positively with the current observation-based WCB classification system.

  1. Wheelchair Navigation System for Disabled and Elderly People

    Directory of Open Access Journals (Sweden)

    Eun Yi Kim

    2016-10-01

    Full Text Available An intelligent wheelchair (IW system is developed in order to support safe mobility for disabled or elderly people with various impairments. The proposed IW offers two main functions: obstacle detection and avoidance, and situation recognition. First, through a combination of a vision sensor and eight ultrasonic ones, it detects diverse obstacles and produces occupancy grid maps (OGMs that describe environmental information, including the positions and sizes of obstacles, which is then given to the learning-based algorithm. By learning the common patterns among OGMs assigned to the same directions, the IW can automatically find paths to prevent collisions with obstacles. Second, it distinguishes a situation whereby the user is standing on a sidewalk, traffic intersection, or roadway through analyzing the texture and shape of the images, which aids in preventing any accidents that would result in fatal injuries to the user, such as collisions with vehicles. From the experiments that were performed in various environments, we can prove the following: (1 the proposed system can recognize different types of outdoor places with 98.3% accuracy; and (2 it can produce paths that avoid obstacles with 92.0% accuracy.

  2. Power Assist Control of Robotic Wheelchair Based on Visual Feedback

    Science.gov (United States)

    Oda, Naoki; Shimizu, Hiroyuki

    This paper describes a vision based self-velocity estimation and its feedback system under force/torque sensor-less power assisting control of wheelchair robot. In this method, three dimensional information obtained by stereo images, and the optical flow vectors are also used for self-velocity estimation in real-time. The human force is estimated by sensor-less reaction force observer, and the assisting force is calculated by using its estimated force and virtual impedance model. In the paper, the force based assist function is integrated into visual feedback motion controller. This approach using vision and force based assist control makes it possible to facilitate the direct intelligent interactions between human force and environments such as human following assist, obstacle avoidance one and so on. Such assist functions are changeable by the selection of the weighting matrix in the velocity estimation, which is based on weighted least square solutions from optical flow vectors. The validity of the proposed approach is verified by several experimental results.

  3. Propulsion Design with Freeform Fabrication Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Propulsion Design with Freeform Fabrication (PDFF) will develop and implement a novel design methodology that leverages the rapidly evolving Solid Freeform...

  4. Aeroelastic Wing Shaping Using Distributed Propulsion

    Science.gov (United States)

    Nguyen, Nhan T. (Inventor); Reynolds, Kevin Wayne (Inventor); Ting, Eric B. (Inventor)

    2017-01-01

    An aircraft has wings configured to twist during flight. Inboard and outboard propulsion devices, such as turbofans or other propulsors, are connected to each wing, and are spaced along the wing span. A flight controller independently controls thrust of the inboard and outboard propulsion devices to significantly change flight dynamics, including changing thrust of outboard propulsion devices to twist the wing, and to differentially apply thrust on each wing to change yaw and other aspects of the aircraft during various stages of a flight mission. One or more generators can be positioned upon the wing to provide power for propulsion devices on the same wing, and on an opposite wing.

  5. Synthesis and evaluation of the smart electric powered wheelchair route stabilization concept – a simulation study

    Directory of Open Access Journals (Sweden)

    Skrzypczyk Krzysztof

    2015-06-01

    Full Text Available The paper addresses the problem of algorithm synthesis for controlling the motion of an electric powered wheelchair. The aim of the algorithm is to stabilize the wheelchair following a linear path and avoiding obstacles if occurred on its way. The main restriction imposed on the project is the application of simple low-cost sensors. That implies the system to cope with a number of inaccuracies and uncertainties related to the measurements. The goal of this work is to evaluate the possibility of the wheelchair project with a navigation system which aids a disable person to move in a complex and dynamic areas. Exemplary simulations are presented in order to discuss the results obtained.

  6. Effects of Offense, Defense, and Ball Possession on Mobility Performance in Wheelchair Basketball.

    Science.gov (United States)

    de Witte, Annemarie M H; Berger, Monique A M; Hoozemans, Marco J M; Veeger, Dirkjan H E J; van der Woude, Lucas H V

    2017-10-01

    The aim of this study was to determine to what extent mobility performance is influenced by offensive or defensive situations and ball possession and to what extent these actions are different for the field positions. From video analysis, the relative duration of the various wheelchair movements during team offense/defense and individual ball possession was compared in 56 elite wheelchair basketball players. A two-way analysis of variance indicated that during offense, the guards and forwards performed longer driving forward than during defense. Overall, centers stood still longer during offense than during defense. Without ball, centers performed driving forward longer than with ball possession. It is concluded that offense, defense, and ball possession influenced mobility performance for the different field positions. These differences can be used to design specific training protocols. Furthermore, field positions require potentially different specific wheelchair configurations to improve performance.

  7. Validity and reliability of tests determining performance-related components of wheelchair basketball.

    Science.gov (United States)

    De Groot, Sonja; Balvers, Inge J M; Kouwenhoven, Sanne M; Janssen, Thomas W J

    2012-05-01

    The purpose of this study was to investigate the reliability and validity of wheelchair basketball field tests. Nineteen wheelchair basketball players performed 10 test items twice to determine the reliability. The validity of the tests was assessed by relating the scores to the players' classification and competition standard, and rating of coach and player. Six field tests' test-retest showed good reliability (Intraclass correlation coefficient (ICC) = 0.80-0.97), while the pass-for-accuracy, free throws, lay-up and spot shot showed weak to moderate reliability (ICC = 0.26-0.67). Most tests showed moderate to good validity (r > 0.60). The results suggest that wheelchair basketball field tests are reliable and valid with the exception of the shooting and passing items, which should be interpreted carefully.

  8. Relationship between aerobic and anaerobic parameters and functional classification in wheelchair basketball players.

    Science.gov (United States)

    de Lira, C A B; Vancini, R L; Minozzo, F C; Sousa, B S; Dubas, J P; Andrade, M S; Steinberg, L L; da Silva, A C

    2010-08-01

    Participation in sports for individuals with disabilities continues to gain popularity. In order to provide fair and equitable competition among persons with different disabilities and functional capacity, a separate functional classification system has been devised for each sport. The aims of the present study were to evaluate aerobic and anaerobic performance of wheelchair basketball athletes and verify a correlation with the International Wheelchair Basketball Federation functional classification system. For this, 17 highly trained male Brazilian basketball wheelchair athletes (25.4+/-4.4 years) from the national team who had taken part in the Athens 2004 Paralympic Games were assessed. These athletes were submitted to cardiopulmonary exercise testing and Wingate-like 30-s sprint test using upper limbs. The present study demonstrated that the functional classification score correlated with relative (r=0.90; Pwheelchair basketball players.

  9. Relation of functional physical impairment and goal perspectives of wheelchair basketball players.

    Science.gov (United States)

    Fliess-Douer, Osnat; Hutzler, Yeshayahu; Vanlandewijck, Yves C

    2003-06-01

    This study examined the relation of functional classification in wheelchair basketball and its relation to the theory of psychological goal perspectives for 59 adult male competitive players. Participants completed the 13-item Task and Ego Orientation in Sport Questionnaire designed for wheelchair basketball players. Analyses indicated that Flemish wheelchair basketball players were similar in their goal perspectives to able-bodied athletes. The present sample was predominantly task-oriented. No significant differences were found between high-point and low-point players in their goal perspectives, indicating that players can be severely or minimally disabled and still share the same goal perspective and the same motivational profile. These findings are not consistent with the hypothesis that severity of disability is associated with the motivation profile of disabled athletes.

  10. A test of self-determination theory with wheelchair basketball players with and without disability.

    Science.gov (United States)

    Perreault, Stephane; Vallarand, Robert J

    2007-10-01

    Guided by Self-Determination Theory (SDT), the present study examined the sport motivation and coping skills of male and female wheelchair basketball players with and without disability (N = 72). In line with SDT, results showed that intrinsic and extrinsic motivation as well as amotivation was found to be present in this sample of wheelchair basketball players. Results also demonstrated that the participants surveyed in the present study scored higher on self-determined types of motivation than non self-determined types of motivation, thus replicating past research with athletes without disability. Furthermore, wheelchair basketball players with and without disability did not differ significantly with respect to sport motivation and coping skills, suggesting that they are more alike than dissimilar. Finally, results revealed that self-determined motivation is associated with enhanced psychological functioning.

  11. Mechanical design and simulation of two-wheeled wheelchair using solidworks

    Science.gov (United States)

    Altalmas, T. M.; Ahmad, S.; Aula, A.; Akmeliawati, R.; Sidek, S. N.

    2013-12-01

    This article is presented a new design of two-wheeled wheelchair that can balance on two wheels to make it suitable in the narrow areas, especially in the domestic environments; it has the ability to extend the height of the chair to help the user to act independently in the life for example, in the library to pick and put books on the shelves. The 3D model has been built up using SolidWorks Software. Nowadays, SolidWorks environment is considered as a powerful tool that is helping designer to design products and attain its performance before physical prototype stage. SolidWorks simulation model has been employed to test the frame of the wheelchair under the weight of the human body and the upper part of the wheelchair. The static analysis has been done on the frame using steel and aluminium; however the aluminium material has been selected due to its light weight

  12. Use of a design challenge to develop postural support devices for intermediate wheelchair users

    Science.gov (United States)

    Tanuku, Deepti; Moller, Nathaniel C.

    2017-01-01

    The provision of an appropriate wheelchair, one that provides proper fit and postural support, promotes wheelchair users’ physical health and quality of life. Many wheelchair users have postural difficulties, requiring supplemental postural support devices for added trunk support. However, in many low- and middle-income settings, postural support devices are inaccessible, inappropriate or unaffordable. This article describes the use of the design challenge model, informed by a design thinking approach, to catalyse the development of an affordable, simple and robust postural support device for low- and middle-income countries. The article also illustrates how not-for-profit organisations can utilise design thinking and, in particular, the design challenge model to successfully support the development of innovative solutions to product or process challenges. PMID:28936418

  13. Use of a design challenge to develop postural support devices for intermediate wheelchair users.

    Science.gov (United States)

    Onguti, Brenda N; Tanuku, Deepti; Himelfarb Hurwitz, Elizabeth J; Moller, Nathaniel C; Yazdi, Youseph; Egan, Shannon; Bazant, Eva S; Gichangi, Anthony

    2017-01-01

    The provision of an appropriate wheelchair, one that provides proper fit and postural support, promotes wheelchair users' physical health and quality of life. Many wheelchair users have postural difficulties, requiring supplemental postural support devices for added trunk support. However, in many low- and middle-income settings, postural support devices are inaccessible, inappropriate or unaffordable. This article describes the use of the design challenge model, informed by a design thinking approach, to catalyse the development of an affordable, simple and robust postural support device for low- and middle-income countries. The article also illustrates how not-for-profit organisations can utilise design thinking and, in particular, the design challenge model to successfully support the development of innovative solutions to product or process challenges.

  14. Use of a design challenge to develop postural support devices for intermediate wheelchair users

    Directory of Open Access Journals (Sweden)

    Brenda N. Onguti

    2017-01-01

    Full Text Available The provision of an appropriate wheelchair, one that provides proper fit and postural support, promotes wheelchair users’ physical health and quality of life. Many wheelchair users have postural difficulties, requiring supplemental postural support devices for added trunk support. However, in many low- and middle-income settings, postural support devices are inaccessible, inappropriate or unaffordable. This article describes the use of the design challenge model, informed by a design thinking approach, to catalyse the development of an affordable, simple and robust postural support device for low- and middle-income countries. The article also illustrates how not-for-profit organisations can utilise design thinking and, in particular, the design challenge model to successfully support the development of innovative solutions to product or process challenges.

  15. Development of a Bayesian neural network to perform obstacle avoidance for an intelligent wheelchair.

    Science.gov (United States)

    Nguyen, Anh V; Nguyen, Lien B; Su, Steven; Nguyen, Hung T

    2012-01-01

    This paper presents an extension of a real-time obstacle avoidance algorithm for our laser-based intelligent wheelchair, to provide independent mobility for people with physical, cognitive, and/or perceptual impairments. The laser range finder URG-04LX mounted on the front of the wheelchair collects immediate environment information, and then the raw laser data are directly used to control the wheelchair in real-time without any modification. The central control role is an obstacle avoidance algorithm which is a neural network trained under supervision of Bayesian framework, to optimize its structure and weight values. The experiment results demonstrated that this new approach provides safety, smoothness for autonomous tasks and significantly improves the performance of the system in difficult tasks such as door passing.

  16. Context-Based Filtering for Assisted Brain-Actuated Wheelchair Driving

    Directory of Open Access Journals (Sweden)

    Gerolf Vanacker

    2007-01-01

    Full Text Available Controlling a robotic device by using human brain signals is an interesting and challenging task. The device may be complicated to control and the nonstationary nature of the brain signals provides for a rather unstable input. With the use of intelligent processing algorithms adapted to the task at hand, however, the performance can be increased. This paper introduces a shared control system that helps the subject in driving an intelligent wheelchair with a noninvasive brain interface. The subject's steering intentions are estimated from electroencephalogram (EEG signals and passed through to the shared control system before being sent to the wheelchair motors. Experimental results show a possibility for significant improvement in the overall driving performance when using the shared control system compared to driving without it. These results have been obtained with 2 healthy subjects during their first day of training with the brain-actuated wheelchair.

  17. Electric Propulsion Platforms at DFRC

    Science.gov (United States)

    Baraaclough, Jonathan

    2009-01-01

    NASA Dryden Flight Research Center is a world-class flight research facility located at Edwards AFB, CA. With access to a 44 sq. mile dry lakebed and 350 testable days per year, it is the ideal location for flight research. DFRC has been undertaking aircraft research for approximately six decades including the famous X-aircraft (X-1 through X-48) and many science and exploration platforms. As part of this impressive heritage, DFRC has garnered more hours of full-sized electric aircraft testing than any other facility in the US, and possibly the world. Throughout the 80 s and 90 s Dryden was the home of the Pathfinder, Pathfinder Plus, and Helios prototype solar-electric aircraft. As part of the ERAST program, these electric aircraft achieved a world record 97,000 feet altitude for propeller-driven aircraft. As a result of these programs, Dryden s staff has collected thousands of man-hours of electric aircraft research and testing. In order to better answer the needs of the US in providing aircraft technologies with lower fuel consumption, lower toxic emissions (NOx, CO, VOCs, etc.), lower greenhouse gas (GHG) emissions, and lower noise emissions, NASA has engaged in cross-discipline research under the Aeronautics Research Mission Directorate (ARMD). As a part of this overall effort, Mark Moore of LaRC has initiated a cross-NASA-center electric propulsion working group (EPWG) to focus on electric propulsion technologies as applied to aircraft. Electric propulsion technologies are ideally suited to overcome all of the obstacles mentioned above, and are at a sufficiently advanced state of development component-wise to warrant serious R&D and testing (TRL 3+). The EPWG includes participation from NASA Langley Research Center (LaRC), Glenn Research Center (GRC), Ames Research Center (ARC), and Dryden Flight Research Center (DFRC). Each of the center participants provides their own unique expertise to support the overall goal of advancing the state-of-the-art in aircraft

  18. The SMPR for the naval propulsion; Les RPMP pour la propulsion navale

    Energy Technology Data Exchange (ETDEWEB)

    Gauducheau, B. [Technicatome, Centre d' Etudes Nucleaires de Saclay, 91 - Gif sur Yvette (France)

    2002-07-01

    The first controlled application of the fissile energy was the american nuclear reactor for the ship propulsion. Since the sixties, the France begun researches to secure the independence of its nuclear propulsion program. The historical aspects, the french program management and the perspectives of the ship nuclear propulsion, are discussed in this paper. (A.L.B.)

  19. Validity and reliability of an inertial sensor for wheelchair court sports performance.

    Science.gov (United States)

    Mason, Barry S; Rhodes, James M; Goosey-Tolfrey, Victoria L

    2014-04-01

    The purpose of the current study was to determine the validity and reliability of an inertial sensor for assessing speed specific to athletes competing in the wheelchair court sports (basketball, rugby, and tennis). A wireless inertial sensor was attached to the axle of a sports wheelchair. Over two separate sessions, the sensor was tested across a range of treadmill speeds reflective of the court sports (1.0 to 6.0 m/s). At each test speed, ten 10-second trials were recorded and were compared with the treadmill (criterion). A further session explored the dynamic validity and reliability of the sensor during a sprinting task on a wheelchair ergometer compared with high-speed video (criterion). During session one, the sensor marginally overestimated speed, whereas during session two these speeds were underestimated slightly. However, systematic bias and absolute random errors never exceeded 0.058 m/s and 0.086 m/s, respectively, across both sessions. The sensor was also shown to be a reliable device with coefficients of variation (% CV) never exceeding 0.9 at any speed. During maximal sprinting, the sensor also provided a valid representation of the peak speeds reached (1.6% CV). Slight random errors in timing led to larger random errors in the detection of deceleration values. The results of this investigation have demonstrated that an inertial sensor developed for sports wheelchair applications provided a valid and reliable assessment of the speeds typically experienced by wheelchair athletes. As such, this device will be a valuable monitoring tool for assessing aspects of linear wheelchair performance.

  20. Development of a Sitting MicroEnvironment Simulator for wheelchair cushion assessment.

    Science.gov (United States)

    Freeto, Tyler; Cypress, Allissa; Amalraj, Sarah; Yusufishaq, Mohamed Shaif; Bogie, Kath M

    2016-08-01

    Pressure ulcers (PU) are a common comorbidity among wheelchair users. An appropriate wheelchair cushion is essential to relieve pressure and reduce PU development during sitting. The microenvironment, specifically excessive heat and moisture, impacts risk for PU development. An effective wheelchair cushion should maintain a healthy microenvironment at the seating interface. Measurement of heat and moisture can characterize microenvironmental conditions at the wheelchair cushion interface under load. We describe the development of a Sitting MicroEnvironment Simulator (SMES) for the reliable assessment of wheelchair cushion microenvironments. The prototype SMES was developed for use mounted on a Materials Testing Systems (MTS) 810(®) uniaxial servo-hydraulic loading rig and used to assess microenvironmental conditions for Jay Medical Jay 2(®), Roho High Profile Dry Floatation(®) and Low Profile Dry Floatation(®) cushions and a novel modular gel cushion. Each cushion was assessed for two hours in triplicate. The SMES was used to load the cushions to 300N ± 10N, with an interface surface temperature of 37 °C±1 °C and fluid delivery of 13 mL/h±1 mL/h of water. Interface temperature and humidity were measured at the left ischial tuberosity (IT) region every five minutes. Heat and moisture responses were similar for the three commercial cushions. The modular gel cushion stayed cooler for at least 15 min longer than any commercial cushion. The SMES maintained performance to technical specifications for over one hundred hours of total testing and is a reliable tool for characterizing the microenvironmental conditions of wheelchair cushions. Published by Elsevier Ltd.

  1. Development of a Low-Cost Electronic Wheelchair with Obstacle Avoidance Feature

    Directory of Open Access Journals (Sweden)

    Edwin Romeroso Arboleda

    2015-12-01

    Full Text Available  A low-cost electronic wheelchair was designed and developed which can perform the similar functions and features as a commercially available wheelchair. It also provides obstacle avoidance capability as added value. The electronic wheelchair was  realized by modification of a lightweight manual wheelchair. It uses two electric motors each of 320 W 24 V DC, 5-24 VDC 6 A H-bride drivers, and a 12 V 17 Ah rechargeable lead acid battery. It equipped with switches, joystick, infrared sensors and ultrasonic sensors. A GizduinoAtMega 328 microcontroller is used to read and interpret commands. User’s acceptance evaluation results shows that the developed low-cost wheelchair is able to receive and interpret commands provided by the joystick, detect if a person  is seated on it, navigate to avoid obstacles as well as to detect edge and stairs. Technical evaluation result shows that on a flat surface it could move at the speed of around 39.9 m/minute without load and 32 m/minute with 80 kg load. At 10 degrees inclined surface, the maximum weight limit is 30 kg with the speed of 12 m/minute. At 20 degrees inclined surface, the maximum weight limit is 10 kg with the speed of 3 m/minute. Regarding cost, it is just a fraction of a cost compared to the commercially available model. Therefore, the developed wheelchair offers an option for potential users who cannot afford to buy the commercially available one.

  2. Influence of long-term wheelchair rugby training on the functional abilities in persons with tetraplegia over a two-year post-spinal cord injury.

    Science.gov (United States)

    Furmaniuk, Lech; Cywińska-Wasilewska, Grazyna; Kaczmarek, Dominik

    2010-07-01

    The aim of this study was to assess the influence of long-term wheelchair rugby training on the functional abilities of persons with tetraplegia over a 2-year period post-spinal cord injury. A prospective non-randomized controlled trial. Forty people with incomplete tetraplegia were examined. Participants were divided into 2 groups: a wheelchair rugby training group (n = 20) and a control group (n = 20). The Wheelchair Skills Test was used to assess functional changes in patients. In order to assess the strength of the 10 key muscles in the upper limb, the American Spinal Injury Association (ASIA) motor score was used. All participants were assessed at the beginning of the study (at the start of wheelchair rugby training) and reassessed after 2 years. Between pre- and post-measurements patients from the wheelchair rugby group attended wheelchair rugby training once a week. The baseline values of the Wheelchair Skills Test in the wheelchair rugby group was 71.3, and this increased significantly by 24%. In the control group, the mean Wheelchair Skills Test value was 63.2, and this improved by 4%. A significant correlation between Wheelchair Skills Test score and ASIA motor score was found in both groups. Participation in regular wheelchair rugby training may preserve and augment functional abilities in individuals with incomplete tetraplegia.

  3. Space storable propulsion components development

    Science.gov (United States)

    Hagler, R., Jr.

    1982-01-01

    The current development status of components to control the flow of propellants (liquid fluorine and hydrazine) in a demonstration space storable propulsion system is discussed. The criteria which determined the designs for the pressure regulator, explosive-actuated valves, propellant shutoff valve, latching solenoid-actuated valve and propellant filter are presented. The test philosophy that was followed during component development is outlined. The results from compatibility demonstrations for reusable connectors, flange seals, and CRES/Ti-6Al4V transition tubes and the evaluations of processes for welding (hand-held TIG, automated TIG, and EB), cleaning for fluorine service, and decontamination after fluorine exposure are described.

  4. Nuclear Electric Propulsion mission operations.

    Science.gov (United States)

    Prickett, W. Z.; Spera, R. J.

    1972-01-01

    Mission operations are presented for comet rendezvous and outer planet exploration missions conducted by unmanned Nuclear Electric Propulsion (NEP) system employing in-core thermionic reactors for electric power generation. The selected reference mission are Comet Halley rendezvous and a Jupiter orbiter at 5.9 planet radii, the orbit of the moon Io. Mission operations and options are defined from spacecraft assembly through mission completion. Pre-launch operations and related GSE requirements are identified. Shuttle launch and subsequent injection to earth escape by the Centaur d-1T are discussed, as well as power plant startup and heliocentric mission phases.

  5. NASA's Nuclear Thermal Propulsion Project

    Science.gov (United States)

    Houts, Mike; Mitchell, Sonny; Kim, Tony; Borowski, Stan; Power, Kevin; Scott, John; Belvin, Anthony; Clement, Steve

    2015-01-01

    HEOMD's (Human Exploration and Operations Mission Directorate) AES (Advanced Exploration Systems) Nuclear Thermal Propulsion (NTP) project is making significant progress. First of four FY 2015 milestones achieved this month. Safety is the highest priority for NTP (as with other space systems). After safety comes affordability. No centralized capability for developing, qualifying, and utilizing an NTP system. Will require a strong, closely integrated team. Tremendous potential benefits from NTP and other space fission systems. No fundamental reason these systems cannot be developed and utilized in a safe, affordable fashion.

  6. Do field position and playing standard influence athlete performance in wheelchair basketball?

    Science.gov (United States)

    de Witte, Annemarie M H; Hoozemans, Marco J M; Berger, Monique A M; van der Woude, Lucas H V; Veeger, Dirkjan H E J

    2016-01-01

    Improved understanding of mobility performance in wheelchair basketball is required to increase game performance. The aim of this study was to quantify the wheelchair-athlete activities of players in different field positions and of different playing standard during wheelchair basketball matches. From video analysis, absolute and relative duration and frequency of wheelchair movements and athlete control options were examined in 27 national standard and 29 international standard players during entire wheelchair basketball matches. Between-group factorial analysis of variances identified that national players drove more forward (42.6 ± 6.8 vs. 35.4 ± 3.7%; effect size Cohen's d (ES) = 1.48) and started more often driving forward (33.9 ± 2.6 vs. 31.8 ± 2.8; ES = 0.77) during a match while the mean activity duration for a single driving forward activity was longer (4.3 ± 0.9 vs. 3.7 ± 0.6 s; ES = 0.75) than for international players. Furthermore, national players performed fewer rotational movements (21.8 ± 4.0 vs. 28.9 ± 7.8%; ES = -1.30) and started less often with the rotational movements (35.0 ± 3.6 vs. 40.5 ± 5.5; ES = -1.21) while the mean activity duration for a single rotation activity was shorter (2.1 ± 0.3 vs. 2.3 ± 0.3 s; ES = -0.67) than for international players. Differences in mobility performance among guard, forward and centre players were minimal. The results should help wheelchair basketball coaches specify wheelchair-handling training techniques and means to optimise wheelchair-athlete configurations.

  7. Comparison of sport achievement orientation of male professional, amateur, and wheelchair basketball athletes.

    Science.gov (United States)

    Skordilis, E K; Gavriilidis, A; Charitou, S; Asonitou, K

    2003-10-01

    To examine the differences in sport achievement orientation among 35 professional, 36 amateur, and 35 wheelchair basketball athletes, these men completed three subscales of Competitiveness, Win orientation, and Goal orientation of the 25-item Sport Orientation Questionnaire. A multivariate analysis of variance indicated significant differences among groups. Win orientation was the factor, through discriminant function analysis, that significantly separated the athletes into the three groups. The highest win score was obtained by the professional, followed by the amateur and wheelchair groups. Replication study is necessary to confirm the present findings.

  8. Towards an Inclusive Virtual Dressing Room for Wheelchair-Bound Customers

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis; Petersson, Eva

    2014-01-01

    , at a reported approximately 40%, is crippling the clothing industry. Results from public response surveys (including at The Scandinavian Health & Rehab Messe) to a VDR simulation system clearly indicated how the wheelchair-bound community perceived benefits from the system. This was unexpected and aside from...... product. This resulted in additional surveys and the evolution of this additional work-in-progress. Following introducing the VDR, key issues such as interface design, body measurement, and cloth representation in the VDR is discussed. The finding of wheelchair-bound-need is envisioned as a next...

  9. Novel Driving Control of Power Assisted Wheelchair Based on Minimum Jerk Trajectory

    Science.gov (United States)

    Seki, Hirokazu; Sugimoto, Takeaki; Tadakuma, Susumu

    This paper describes a novel trajectory control scheme for power assisted wheelchair. Human input torque patterns are always intermittent in power assisted wheelchairs, therefore, the suitable trajectories must be generated also after the human decreases his/her input torque. This paper tries to solve this significant problem based on minimum jerk model minimizing the changing rate of acceleration. The proposed control system based on minimum jerk trajectory is expected to improve the ride quality, stability and safety. Some experiments show the effectiveness of the proposed method.

  10. Dynamic cerebral autoregulation changes during sub-maximal handgrip maneuver.

    Directory of Open Access Journals (Sweden)

    Ricardo C Nogueira

    Full Text Available PURPOSE: We investigated the effect of handgrip (HG maneuver on time-varying estimates of dynamic cerebral autoregulation (CA using the autoregressive moving average technique. METHODS: Twelve healthy subjects were recruited to perform HG maneuver during 3 minutes with 30% of maximum contraction force. Cerebral blood flow velocity, end-tidal CO₂ pressure (PETCO₂, and noninvasive arterial blood pressure (ABP were continuously recorded during baseline, HG and recovery. Critical closing pressure (CrCP, resistance area-product (RAP, and time-varying autoregulation index (ARI were obtained. RESULTS: PETCO₂ did not show significant changes during HG maneuver. Whilst ABP increased continuously during the maneuver, to 27% above its baseline value, CBFV raised to a plateau approximately 15% above baseline. This was sustained by a parallel increase in RAP, suggestive of myogenic vasoconstriction, and a reduction in CrCP that could be associated with metabolic vasodilation. The time-varying ARI index dropped at the beginning and end of the maneuver (p<0.005, which could be related to corresponding alert reactions or to different time constants of the myogenic, metabolic and/or neurogenic mechanisms. CONCLUSION: Changes in dynamic CA during HG suggest a complex interplay of regulatory mechanisms during static exercise that should be considered when assessing the determinants of cerebral blood flow and metabolism.

  11. Propulsion

    Science.gov (United States)

    Smith, P. K.

    1993-06-01

    Current requirements for missile systems increasingly stress the need for stealth capability. For the majority of missile systems and missions, the exhaust plume is likely to be the major contributor to overall missile signature, especially considering the recent developments in low emission and low Radar Cross Section coatings for motor bodies. This implies the need for the lowest possible rocket exhaust signature over a wide range of frequencies from the UV through visible and IR to microwave and radio frequencies. The choice of propellant type, Double Base; Composite etc, plays a significant part in determining the exhaust signature of the rocket motor as does the selection of inert materials for liners, inhibitors, and nozzles. It is also possible with certain propellants to incorporate additives which reduce exhaust signature either by modifying the chemistry or the afterburning plume or more significantly by suppressing secondary combustion and hence dramatically reducing plume temperature. The feasibility of plume signature control on the various missions envisaged by the missile designer is considered. The choice of propellant type and hardware components to give low signature is discussed together with performance implications. Signature reduction results obtained over a wide range of frequencies are also presented.

  12. Feasibility of MHD submarine propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Doss, E.D. (ed.) (Argonne National Lab., IL (United States)); Sikes, W.C. (ed.) (Newport News Shipbuilding and Dry Dock Co., VA (United States))

    1992-09-01

    This report describes the work performed during Phase 1 and Phase 2 of the collaborative research program established between Argonne National Laboratory (ANL) and Newport News Shipbuilding and Dry Dock Company (NNS). Phase I of the program focused on the development of computer models for Magnetohydrodynamic (MHD) propulsion. Phase 2 focused on the experimental validation of the thruster performance models and the identification, through testing, of any phenomena which may impact the attractiveness of this propulsion system for shipboard applications. The report discusses in detail the work performed in Phase 2 of the program. In Phase 2, a two Tesla test facility was designed, built, and operated. The facility test loop, its components, and their design are presented. The test matrix and its rationale are discussed. Representative experimental results of the test program are presented, and are compared to computer model predictions. In general, the results of the tests and their comparison with the predictions indicate that thephenomena affecting the performance of MHD seawater thrusters are well understood and can be accurately predicted with the developed thruster computer models.

  13. Numerical Propulsion System Simulation Architecture

    Science.gov (United States)

    Naiman, Cynthia G.

    2004-01-01

    The Numerical Propulsion System Simulation (NPSS) is a framework for performing analysis of complex systems. Because the NPSS was developed using the object-oriented paradigm, the resulting architecture is an extensible and flexible framework that is currently being used by a diverse set of participants in government, academia, and the aerospace industry. NPSS is being used by over 15 different institutions to support rockets, hypersonics, power and propulsion, fuel cells, ground based power, and aerospace. Full system-level simulations as well as subsystems may be modeled using NPSS. The NPSS architecture enables the coupling of analyses at various levels of detail, which is called numerical zooming. The middleware used to enable zooming and distributed simulations is the Common Object Request Broker Architecture (CORBA). The NPSS Developer's Kit offers tools for the developer to generate CORBA-based components and wrap codes. The Developer's Kit enables distributed multi-fidelity and multi-discipline simulations, preserves proprietary and legacy codes, and facilitates addition of customized codes. The platforms supported are PC, Linux, HP, Sun, and SGI.

  14. Propulsive force in front crawl swimming

    NARCIS (Netherlands)

    Berger, M.A.M.; de Groot, G.; Hollander, A.P.

    1999-01-01

    To evaluate the propulsive forces in front crawl arm swimming, derived from a three-dimensional kinematic analysis, these values were compared with mean drag forces. The propulsive forces during front crawl swimming using the arms only were calculated using three-dimensional kinematic analysis

  15. 46 CFR 109.555 - Propulsion boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion boilers. 109.555 Section 109.555 Shipping... Miscellaneous § 109.555 Propulsion boilers. The master or person in charge and the engineer in charge shall ensure that— (a) Steam pressure does not exceed that allowed by the certificate of inspection; and (b...

  16. Electrostatic Propulsion Using C60 Molecules

    Science.gov (United States)

    Leifer, Stephanie D.; Saunders, Winston A.

    1993-01-01

    Report proposes use of C60 as propellant material in electrostatic propulsion system of spacecraft. C60, C70, and similar molecules, have recently been found to have characteristics proving advantageous in electrostatic propulsion. Report discusses these characteristics and proposes experiments to determine feasibility of concept.

  17. 46 CFR 130.120 - Propulsion control.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion control. 130.120 Section 130.120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS VESSEL CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Vessel Control § 130.120 Propulsion control. (a) Each vessel must have— (1...

  18. A hybrid brain computer interface to control the direction and speed of a simulated or real wheelchair.

    Science.gov (United States)

    Long, Jinyi; Li, Yuanqing; Wang, Hongtao; Yu, Tianyou; Pan, Jiahui; Li, Feng

    2012-09-01

    Brain-computer interfaces (BCIs) are used to translate brain activity signals into control signals for external devices. Currently, it is difficult for BCI systems to provide the multiple independent control signals necessary for the multi-degree continuous control of a wheelchair. In this paper, we address this challenge by introducing a hybrid BCI that uses the motor imagery-based mu rhythm and the P300 potential to control a brain-actuated simulated or real wheelchair. The objective of the hybrid BCI is to provide a greater number of commands with increased accuracy to the BCI user. Our paradigm allows the user to control the direction (left or right turn) of the simulated or real wheelchair using left- or right-hand imagery. Furthermore, a hybrid manner can be used to control speed. To decelerate, the user imagines foot movement while ignoring the flashing buttons on the graphical user interface (GUI). If the user wishes to accelerate, then he/she pays attention to a specific flashing button without performing any motor imagery. Two experiments were conducted to assess the BCI control; both a simulated wheelchair in a virtual environment and a real wheelchair were tested. Subjects steered both the simulated and real wheelchairs effectively by controlling the direction and speed with our hybrid BCI system. Data analysis validated the use of our hybrid BCI system to control the direction and speed of a wheelchair.

  19. Contributions of selected fundamental factors to wheelchair basketball performance.

    Science.gov (United States)

    Wang, Yong T; Chen, Shihui; Limroongreungrat, Weerawat; Change, Li-Shan

    2005-01-01

    The purpose of this study was to determine the contributions of selected fundamental factors, such as arm length, sitting height, simple vision reaction time (SVRT), choice vision reaction time (CVRT), muscle strength, and range of motion (ROM) at the shoulder, elbow, and wrist joints to wheelchair basketball (WCB) performance as measured by season statistics and coaches' evaluation. Thirty-seven Paralympic WCB players from seven countries participated in this study. A computerized reaction time system was used to test the SVRT and CVRT. The ROM and muscle strengths of the shoulder, elbow, and wrist joints were measured using a goniometer and MP DA100B BioPac force measurement system, respectively. Stepwise regression analysis was used to identify the contributions of these fundamental factors and "dimensional variables" (DV) derived from the selected factors fundamental to WCB performance. A DV represented a dimension or category of the factor, for example, the wrist flexion/extension DV represented the ROM of the wrist in flexion and extension, and the WCB performance DV represented average points, rebounds, assists, blocks, and steals per game. The results of this study demonstrated that elbow extension and wrist extension had significant contributions to average points. Sitting height, shoulder internal rotation, and elbow flexion had significant contributions to the average rebounds. Arm length had a significant contribution to average assists, and SVRT had a significant contribution to the average blocks. Wrist flexion/extension ROM DV and wrist flexion/extension strength DV had significant contributions to the WCB performance DV. Shoulder internal rotation, elbow extension, and wrist flexion/extension ROM, CVRT, and wrist flexion/extension muscle strength are important to WCB performance and should be addressed in WCB training.

  20. External And Internal Work Of A T-6 Paraplegic Propelling A Wheelchair And Arm Cranking A Cycle Ergometer: Case Study

    Science.gov (United States)

    Novak, Charles W.

    1982-02-01

    In this, the International Year of the Disabled, attention is directed among other areas toward rehabilitation and sports participation of wheelchair users. As an application of movement analysis in medicine and rehabilitation and as an application of sports research using biomechanics, this investigation was performed to compare the results of two methods of gathering data on the stress of wheelchair propelling at equivalent work loads and to account for differences in physiological responses with a mechanical analysis of wheelchair propelling. Physiological data collected were heart rate, systolic blood pressure, and rate-pressure product. A biomechanical cinematography analysis was used to determine external work in wheelchair propelling and to determine the extent to which modifications in segment actionsoccurred during increasing magnitude of work. A cycle ergometer was adjusted to replicate external work loads performed during wheelchair propelling. A t-test of equivalent external work loads indicated that heart rate was not different between the two exercise modes at the .05 level of significance. The t-test did indicate a significant difference in systolic blood pressure and rate-pressure product at the .05 level of significance. The biomechanical analysis of wheelchair propelling established that an increase in external work was accomplished by a decrease in the range of motion and an increase in the speed of movement. During cycle ergometry the range and speed of movement remained the same while resistance was increased. Results of the study established that while heart rate for equivalent external work loads was the same for wheelchair propelling and arm cranking cycle ergometry, systolic blood pressure and rate-pressure product were not the same. The suggestion was that some means of propelling a wheelchair other than that which is con-sidered "standard" might be considered which produces less stressful responses in wheelchair users.

  1. Simulation Propulsion System and Trajectory Optimization

    Science.gov (United States)

    Hendricks, Eric S.; Falck, Robert D.; Gray, Justin S.

    2017-01-01

    A number of new aircraft concepts have recently been proposed which tightly couple the propulsion system design and operation with the overall vehicle design and performance characteristics. These concepts include propulsion technology such as boundary layer ingestion, hybrid electric propulsion systems, distributed propulsion systems and variable cycle engines. Initial studies examining these concepts have typically used a traditional decoupled approach to aircraft design where the aerodynamics and propulsion designs are done a-priori and tabular data is used to provide inexpensive look ups to the trajectory ana-ysis. However the cost of generating the tabular data begins to grow exponentially when newer aircraft concepts require consideration of additional operational parameters such as multiple throttle settings, angle-of-attack effects on the propulsion system, or propulsion throttle setting effects on aerodynamics. This paper proposes a new modeling approach that eliminated the need to generate tabular data, instead allowing an expensive propulsion or aerodynamic analysis to be directly integrated into the trajectory analysis model and the entire design problem optimized in a fully coupled manner. The new method is demonstrated by implementing a canonical optimal control problem, the F-4 minimum time-to-climb trajectory optimization using three relatively new analysis tools: Open M-DAO, PyCycle and Pointer. Pycycle and Pointer both provide analytic derivatives and Open MDAO enables the two tools to be combined into a coupled model that can be run in an efficient parallel manner that helps to cost the increased cost of the more expensive propulsion analysis. Results generated with this model serve as a validation of the tightly coupled design method and guide future studies to examine aircraft concepts with more complex operational dependencies for the aerodynamic and propulsion models.

  2. Effects of offense, defense, and ball possession on mobility performance in wheelchair basketball

    NARCIS (Netherlands)

    De Witte, Annemarie M.H.; Berger, Monique A.M.; Hoozemans, Marco J.M.; Veeger, H.E.J.; van der Woude, Lucas H.V.

    2017-01-01

    The aim of this study was to determine to what extent mobility performance is influenced by offensive or defensive situations and ball possession and to what extent these actions are different for the field positions. From video analysis, the relative duration of the various wheelchair movements

  3. Effects of modified multistage field test on performance and physiological responses in wheelchair basketball players.

    Science.gov (United States)

    Weissland, Thierry; Faupin, Arnaud; Borel, Benoit; Berthoin, Serge; Leprêtre, Pierre-Marie

    2015-01-01

    A bioenergetical analysis of manoeuvrability and agility performance for wheelchair players is inexistent. It was aimed at comparing the physiological responses and performance obtained from the octagon multistage field test (MFT) and the modified condition in "8 form" (MFT-8). Sixteen trained wheelchair basketball players performed both tests in randomized condition. The levels performed (end-test score), peak values of oxygen uptake (VO2peak), minute ventilation (VEpeak), heart rate (HRpeak), peak and relative blood lactate (Δ[Lact(-)] = peak--rest values), and the perceived rating exertion (RPE) were measured. MFT-8 induced higher VO2peak and VEpeak values compared to MFT (VO2peak: 2.5 ± 0.6 versus 2.3 ± 0.6 L · min(-1) and VEpeak: 96.3 ± 29.1 versus 86.6 ± 23.4 L · min(-1); P wheelchair players, MFT-8 had no effect on test performance but generates higher physiological responses than MFT. It could be explained by demands of wheelchair skills occurring in 8 form during the modified condition.

  4. Effects of Offense, Defense, and Ball Possession on Mobility Performance in Wheelchair Basketball

    NARCIS (Netherlands)

    de Witte, Annemarie M. H.; Berger, Monique A. M.; Hoozemans, Marco J. M.; Veeger, Dirkjan H. E. J.; van der Woude, Lucas H. V.

    2017-01-01

    The aim of this study was to determine to what extent mobility performance is influenced by offensive or defensive situations and ball possession and to what extent these actions are different for the field positions. From video analysis, the relative duration of the various wheelchair movements

  5. Transportation of Wheelchair Seated Students in School Buses: A Review of State Policy

    Science.gov (United States)

    Moore, Britta; Fuhrman, Susan; Karg, Patricia

    2010-01-01

    This study quantitatively reviews publicly available state policies as they relate to the transportation of wheelchair-seated students in school buses. Inclusion of best practices in specially equipped school bus and driver training policies was assessed. Key points of interest within state policies were identified based on site visits, common…

  6. Communicating in and through "Murderball": Masculinity and Disability in Wheelchair Rugby

    Science.gov (United States)

    Lindemann, Kurt; Cherney, James L.

    2008-01-01

    This article investigates communicative practices surrounding wheelchair rugby, a growing sport played worldwide by people with quadriplegia. Researchers have studied extensively the practice of using sport for rehabilitation, but the role of communication in this process has been overlooked. We argue that participating in this sport is itself a…

  7. Perspectives on Physical Activity Among People with Multiple Sclerosis Who Are Wheelchair Users

    Science.gov (United States)

    Learmonth, Yvonne C.; Rice, Ian M.; Ostler, Teresa; Rice, Laura A.

    2015-01-01

    Background: People with advanced multiple sclerosis (MS) are less physically active than those with milder forms of the disease, and wheelchair use has a negative association with physical activity participation. Thus, wheelchair users with MS are doubly disadvantaged for accruing the benefits of physical activity and exercise. Appropriate physical activity and exercise interventions are needed for this population. Methods: We undertook a qualitative study to explore the meanings, motivations, and outcomes of physical activity in wheelchair users with MS. We sought to understand daily opportunities to accumulate physical activity and exercise, and to identify perceived barriers, facilitators, and benefits that might inform the design of future interventions. Results: We interviewed 15 wheelchair users (mean age, 52 ± 8.8 years; n = 12 women). Data were transcribed and analyzed to identify and explore common themes. Our first theme was the reduced opportunity to participate in physical activity due to participants' dependence on mobility devices, environmental adaptations, and tangible support. Our second theme was the importance of incorporating physical activity and exercise into the everyday environment, highlighting the need for adaptive exercise and accessible environments. This indicated the need to incorporate behavior change modulators into physical activity and exercise interventions for those with advanced MS. Health-care professionals played an important role in promoting increased physical activity and exercise participation in those with advanced MS. Conclusions: Our findings may inform future interventions to increase initiation and maintenance of physical activity and exercise among people with advanced MS. PMID:26052256

  8. Physical capacity after 7 weeks of low-intensity wheelchair training

    NARCIS (Netherlands)

    Van Den Berg, Rosaline; De Groot, Sonja; Swart, Karin M. A.; Van Der Woude, Lucas H. V.

    2010-01-01

    Purpose. To simulate the effect of low-intensity exercise in early rehabilitation, we investigated the effect of a 7-week low-intensity norm duration hand rim wheelchair training on the physical capacity in untrained able-bodied individuals. Method. Twenty-five able-bodied participants were randomly

  9. Sleep quality and depression of nursing home older adults in wheelchairs after exercises.

    Science.gov (United States)

    Chen, Kuei-Min; Huang, Hsin-Ting; Cheng, Yin-Yin; Li, Chun-Huw; Chang, Ya-Hui

    2015-01-01

    Sleep disturbances and depression are costly and potentially disabling conditions that affect a considerable proportion of older adults. The purpose of this study was to test the effectiveness of 6 months of elastic band exercises on sleep quality and depression of wheelchair-bound older adults in nursing homes. One hundred twenty-seven older adults from 10 nursing homes participated in this cluster randomized controlled trial, and 114 completed the study. Participants were randomly assigned to two groups: experimental group (five nursing homes, n = 59) and control group (five nursing homes, n = 55). A 40-minute wheelchair-bound senior elastic band exercise program was implemented 3 times per week for 6 months. Sleep quality and depression of the participants were examined at baseline, after 3 months, and at the end of the 6-month study. Participants in the experimental group had longer sleep durations, better habitual sleep efficiencies, and less depression than the control group at 3 months of the study and maintained them throughout the rest of the 6-month study. Nursing home directors could recruit volunteers to learn the program and lead the elderly residents in wheelchairs in practicing the wheelchair-bound senior elastic band exercises regularly in the facilities. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. The psychosocial impact of wheelchair tennis on participants from developing countries.

    Science.gov (United States)

    Richardson, Emma V; Papathomas, Anthony; Smith, Brett; Goosey-Tolfrey, Victoria L

    2017-01-01

    Individuals with physical disabilities in developing countries can experience many instances of psychosocial hardship. Although scholars have suggested that participation in sport can positively impact psychosocial health, few studies have explored this phenomenon within the disabled population of developing nations. Sixteen wheelchair tennis players were recruited across six developing countries and interviewed in regards to their experiences. Data were collected using semi-structured interviews, transcribed verbatim and subject to thematic analysis. Wheelchair tennis players perceived their participation in sport enhanced their psychosocial well-being. Three broad themes emerged from analysis of the interviews; (1) developed transferrable skills, (2) perceived personal growth and (3) benefits of an athletic identity. Sports participation, in this case wheelchair tennis, may be a viable means to promote psychosocial well-being in disabled populations within developing nations. Moreover, sport holds the potential to challenge negative perceptions of disability at an individual and societal level within these cultures. Implication for Rehabilitation Individuals with physical disabilities in developing countries may experience psychosocial hardship and cultural stigma. Wheelchair sport may be a viable means to enhance psychosocial well-being in this population. Skills learnt "on court" are transferrable to everyday life potentially improving independence and quality of life. Identifying as an athlete can challenge negative cultural perceptions of disability.

  11. The Implementation and Validation of a Virtual Environment for Training Powered Wheelchair Manoeuvres.

    Science.gov (United States)

    John, Nigel W; Pop, Serban R; Day, Thomas W; Ritsos, Panagiotis D; Headleand, Christopher J

    2017-05-02

    Navigating a powered wheelchair and avoiding collisions is often a daunting task for new wheelchair users. It takes time and practice to gain the coordination needed to become a competent driver and this can be even more of a challenge for someone with a disability. We present a cost-effective virtual reality (VR) application that takes advantage of consumer level VR hardware. The system can be easily deployed in an assessment centre or for home use, and does not depend on a specialized high-end virtual environment such as a Powerwall or CAVE. This paper reviews previous work that has used virtual environments technology for training tasks, particularly wheelchair simulation. We then describe the implementation of our own system and the first validation study carried out using thirty three able bodied volunteers. The study results indicate that at a significance level of 5% then there is an improvement in driving skills from the use of our VR system. We thus have the potential to develop the competency of a wheelchair user whilst avoiding the risks inherent to training in the real world. However, the occurrence of cybersickness is a particular problem in this application that will need to be addressed.

  12. Peering into a Crystal Ball: What's the Future for Wheelchair-Seated Travel?

    Science.gov (United States)

    van Roosmalen, Linda; Hobson, Douglas

    2008-01-01

    Over the past year, a team of transportation engineers, product designers, and therapists has been writing a series of articles about wheelchair transportation safety in partnership with "EP." These experts understand the importance of transportation for social inclusion, maintaining health, and being able to get to school and work. Previous…

  13. Efficacy of a powered wheelchair simulator for school aged children: a randomized controlled trial.

    Science.gov (United States)

    Linden, Mark A; Whyatt, Caroline; Craig, Cathy; Kerr, Claire

    2013-11-01

    To determine the efficacy of a custom-made wheelchair simulation in training children to use a powered wheelchair (PWC). Randomized controlled trial employing the 4C/ID-model of learning. Twenty-eight typically developing children (13M, 15F; mean age 6 years, SD 6 months) were assessed on their operation of a PWC using a functional evaluation rating scale. Participants were randomly assigned to intervention (8 × 30-minute training sessions using a joystick operated wheelchair simulation) or control conditions (no task), and were reassessed on their PWC use after the intervention phase. Additional data from the simulation on completion times, errors, and total scores were recorded for the intervention group. Analysis of variance showed a main effect of time, with planned comparisons revealing a statistically significant change in PWC use for the intervention (p = .022) but not the control condition. Although the intervention group showed greater improvement than the controls, this did not reach statistical significance. Multiple regression analyses showed that gender was predictive of pretest (p = .005) functional ability. A simulated wheelchair task appears to be effective in helping children learn to operate a PWC. Greater attention should be given to female learners who underperformed when compared with their male counterparts. This low-cost intervention could be easily used at home to reduce PWC training times in children with motor disorders. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  14. Making distribution of wheelchairs sustainable: A Wheels for the World program in North India, October 2015

    Directory of Open Access Journals (Sweden)

    Jubin Varghese

    2015-01-01

    Full Text Available A description of a program carried out in October 2015 in North India of distribution of wheelchairs and other assistive devices for persons with disabilities. Applying cooperative approaches through churches, NGOs and networks, outside resources were utilized to develop a sustainable approach to meeting identified disability needs in low-resource settings.

  15. Wheelchair-specific fitness of inactive people with long-term spinal cord injury

    NARCIS (Netherlands)

    van der Scheer, Jan W.; de Groot, Sonja; Tepper, Marga; Gobets, David; Veeger, DirkJan H. E. J.; van der Woude, Lucas H. V.

    Objectives: To describe wheelchair-specific anaerobic work capacity, isometric strength and peak aerobic work capacity of physically inactive people with long-term spinal cord injury using outcomes of tests that are feasible for use in rehabilitation centres, and to determine associations among

  16. A navigation system for increasing the autonomy and the security of powered wheelchairs.

    Science.gov (United States)

    Fioretti, S; Leo, T; Longhi, S

    2000-12-01

    Assistive technology is an emerging area where some robotic devices can be used to strengthen the residual abilities of individuals with motor disabilities or to substitute their missing function thus helping them to gain a level of independence at least in the activities of daily living. This paper presents the design of a navigation system and its integration with a commercial powered wheelchair. The navigation system provides the commercial wheelchair with a set of functions which increase the autonomy of elderly and people with motor disabilities. In general, a robot device must be adapted to assistive applications in such a way as to be easily managed by the user. Users, especially young ones, prefer to directly control the robotic device and this aspect of usability has to be managed without affecting the security and efficiency of the navigation module. These aspects have been considered as specifications for the navigation module of powered wheelchairs. Different autonomy levels of the navigation module and proper user interfaces have been developed. Two autonomy levels have been designed. Simple collision avoidance is also implemented in order to stop the mobile base when an obstacle is detected. The preliminary technical tests performed on the navigation system have shown satisfactory results in terms of security and response time. A modular solution for the navigation module was considered in order to simplify the adaptation of the module to different powered wheelchairs.

  17. Influence of wheel configuration on wheelchair basketball performance : Wheel stiffness, tyre type and tyre orientation

    NARCIS (Netherlands)

    Mason, B. S.; Lemstra, M.; van der Woude, L. H. V.; Vegter, R.; Goosey-Tolfrey, V. L.

    The aim of the current investigation was to explore the lateral stiffness of different sports wheelchair wheels available to athletes in 'new' and 'used' conditions and to determine the effect of (a) stiffness, (b) tyre type (clincher vs. tubular) and (c) tyre orientation on the physiological and

  18. The Relationship between Wheelchair Mobility Patterns and Community Participation among Individuals with Spinal Cord Injury

    Science.gov (United States)

    Cooper, Rory A.; Ferretti, Eliana; Oyster, Michelle; Kelleher, Annmarie; Cooper, Rosemarie

    2011-01-01

    Participation is considered the most meaningful outcome of rehabilitation. The purpose of this study was to investigate whether there were correlations between wheelchair activity recorded with a data logger and community participation as measured by the Participation Survey/Mobility. Data from 16 participants were included in this study. Data…

  19. Shoulder Pain in Cases of Spinal Injury: Influence of the Position of the Wheelchair Seat

    Science.gov (United States)

    Giner-Pascual, Manuel; Alcanyis-Alberola, Modesto; Millan Gonzalez, Luis; Aguilar-Rodriguez, Marta; Querol, Felipe

    2011-01-01

    The objective of this study was to determine the relationship between shoulder pain and the position of the seat of a wheelchair relative to the ground and to determine the relationship between shoulder pain and structural damage. A transversal study of a patient cohort of 140 patients with grade A and B spinal cord injuries below the T1 vertebra,…

  20. Evaluation of a stair-climbing power wheelchair in 25 people with tetraplegia.

    Science.gov (United States)

    Laffont, Isabelle; Guillon, Bruno; Fermanian, Christophe; Pouillot, Sophie; Even-Schneider, Alexia; Boyer, François; Ruquet, Maria; Aegerter, Philippe; Dizien, Olivier; Lofaso, Frédéric

    2008-10-01

    To compare the performance of a power wheelchair with stair-climbing capability (TopChair) and a conventional power wheelchair (Storm3). A single-center, open-label study. A physical medicine and rehabilitation hospital. Patients (N=25) who required power wheelchairs because of severe impairments affecting the upper and lower limbs. Indoor and outdoor driving trials with both devices. Curb-clearing and stair-climbing with TopChair. Trial duration and Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST) tool; number of failures during driving trials and ability to climb curbs and stairs. All 25 participants successfully completed the outdoor and indoor trials with both wheelchairs. Although differences in times to trial completion were statistically significant, they were less than 10%. QUEST scores were significantly better with the Storm3 than the TopChair for weight (P=.001), dimension (P=.006), and effectiveness (P=.04). Of the 25 participants, 23 cleared a 20-cm curb without help, and 20 climbed up and down 6 steps. Most participants felt these specific capabilities of the TopChair--for example, curb clearing and stair climbing-were easy to use (22/25 for curb, 21/25 for stairs) and helpful (24/25 and 23/25). A few participants felt insecure (4/25 and 6/25, respectively). The TopChair is a promising mobility device that enables stair and curb climbing and warrants further study.