Studies have shown locomotor adaptation of the ankle to assistive torques, but the ability of the knee to adapt to assistive forces has not yet been explored. Understanding how humans modulate knee joint kinematics during gait could be valuable for designing assistive devices for stroke patients. In this study we examined how healthy subjects adapt to knee flexion torque assistance during gait. We hypothesized that 1) when given assistance subjects would adapt their locomotor patterns to walk with kinematics similar to baseline values and 2) removal of assistance following adaptation would result in substantially reduced knee flexion. Contrary to expectations, data from the five subjects show a weak adaptation and an increase in knee flexion kinematics after forces were removed. These results suggest that neuromuscular control of the knee joint during walking is not strongly modulated by feedforward mechanisms.

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Background: Current neuroscience has identified rehabilitation approaches with the potential to stimulate adaptive changes in the brains of persons with hemiparesis. These approaches include, intensive task-oriented training, bimanual activities and balancing proximal and distal upper extremity interventions to reduce competition between these segments for neural territory. Methods: This paper describes the design and feasibility testing of a robotic/virtual environment system designed to train the hand and arm of persons with hemiparesis. The system employs a simulated piano that presents visual, auditory and tactile feedback comparable to an actual piano. Arm tracking allows patients to train both the arm and hand as a coordinated unit, emphasizing the integration of both transport and manipulation phases. The piano trainer includes songs and scales that can be performed with one or both hands. Adaptable haptic assistance is available for more involved subjects. An algorithm adjusts task difficulty in proportion to subject performance. A proof of concept study was performed on four subjects with upper extremity hemiparesis secondary to chronic stroke to establish: a) the safety and feasibility of this system and b) the concurrent validity of robotically measured kinematic and performance measures to behavioral measures of upper extremity function. Results: None of the subjects experienced adverse events or responses during or after training. As a group, the subjects improved in both performance time and key press accuracy. Three of the four subjects demonstrated improvements in fractionation, the ability to move each finger individually. Two subjects improved their aggregate time on the Jebsen Test of Hand Function and three of the four subjects improved in Wolf Motor Function Test aggre-gate time. Conclusion: The system designed in this paper has proven to be safe and feasible for the training of hand function for persons with hemiparesis. It features a flexible design that allows for the use and further study of adjustments in point of view, bilateral and unimanual treatment modes, adaptive training algorithms and haptically rendered collisions in the context of reha-bilitation of the hemiparetic hand.

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A combined 450,000 Americans suffer from multiple sclerosis, chronic carpal tunnel syndrome, and muscular dystrophy; debilitative disorders that result in a loss of muscle strength and dexterity within the afflicted individual. A controlled orthoticexoskeleton presents a solution by amplifying a user’s residual strength to restore precision pinch and/or power grasp motions. In order to optimize system response time and control accuracy, a two-bit binary state control algorithm was designed using LabVIEW v8.5. The states of the control system were refined using positional and object-sensing information supplied via negative feedback from Hall effect angular sensors and force sensing resistors. Forearm EMG was recorded and used to characterize hand strength with and without the mechanical assistance generated from the hand-assistive exoskeleton. The control system was tested using simulated sensor feedback data and has proven to be a robust design. The controller will be integrated with a glove-like, hand-based exoskeleton. The complete system was designed to restore hand functionality through the amplification of precision pinch and/or power grasp.

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Like many developed Asian countries, Western nations are facing an aging society. This places huge burdens on current healthcare systems. How can we cope with the rapidly increasing demand for healthcare? A wider use of technology is one possible solution. Japan is at the forefront of attempts to develop robotic technology in the service of its citizens, in particular the older members of its population. To learn from the Japanese experience, we visited the country to assess the current state of healthcare robotics there. The present report is intended as a contribution to the debate on the future of our healthcare system. We hope it will bridge the gap between the healthcare providers and the developers of robotics systems, and provide a basis for further discussion and practical collaboration. This study is a joint enterprise of the Rathenau Instituut in The Hague and the Science and Technology section of the Dutch Embassy in Tokyo. Ying Ying Lau from the Rathenau Instituut collected in-formation through interviews and laboratory visits in Japan in the period from September to December 2008. Her work was supervised by Daan Archer, Science and Technology Attaché at the Embassy and Technology Assessment researchers Christian van ‘t Hof and Rinie van Est from the Rathenau Instituut. At the end of November 2008, they visited several laboratories to talk to experts. They were accompanied during some of these visits by a delegation of Dutch healthcare managers, who provided them with feedback on their experi-ence of Japanese robotics. The study was rounded off by an expert meeting at the Dutch Embassy in Tokyo on 27 November 2008, where the future of healthcare robotics in Japan was discussed. This report is the beginning of a larger set of activities in the field of robotics in the Netherlands. In November 2009 an international conference on robotics will be held by SenterNovem (an innovation agency of the Dutch Ministry of Economic Affairs), the Dutch Ministry of Education, Culture and Science and the Rathenau Instituut. Various investigations will be carried out in preparation for this event. For example, the athenau Instituut will carry out an exploratory study on service robots. The Rathenau Instituut will also study developments in the field of healthcare robotics in the Netherlands. We would like to thank all the robotics experts who have contributed to our understanding of the current developments in Japan. The meetings and institutes are mentioned in Appendix A. We also owe a debt of gratitude to the staff of the Dutch Embassy in Tokyo and look forward to future collaboration.

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A high-power electrostatic actuator comprising rotor and stator layers with fault-tolerant electrode structures, a housing to contain the electrodes and dielectric fluid, and electronic circuitry driving a plurality of high-voltage phases. The actuator is constructed from multiple rotor and stator films separated by spacing elements. The electrode structure provides self-alignment for precise assembly. The actuator assembly includes built-in fine-position sensors to allow optimal timing in powering phases, and a coarse position sensor for feedback control. The electrode structure has a large region of linear force to provide low torque-ripple allowing simple high/low voltage pulsing instead of analog high voltage waveforms. Single or double sided flexible circuit manufacturing techniques are used to fabricate the rotor and stator films at low cost.

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