Background: It has been shown that intense training can significantly improve post-stroke upperlimb functionality. However, opportunities for stroke survivors to practice rehabilitation exercises can be limited because of the finite availability of therapists and equipment. This paper presents a haptic-enabled exercise platform intended to assist therapists and mo-derate-level stroke survivors perform upper-limb reaching motion therapy. This work extends on existing knowledge by presenting: 1) an anthropometrically-inspired design that maximizes elbow and shoulder range of motions during exercise; 2) an unobtrusive upper body postural sensing system; and 3) a vibratory elbow stimulation device to encourage muscle movement. Methods: A multi-disciplinary team of professionals were involved in identifying the rehabilitation needs of stroke survivors incorporating these into a proto-type device. The prototype system consisted of an exercise device, postural sensors, and a elbow stimula- tion to encourage the reaching movement. Eight experienced physical and occupational therapists partici-pated in a pilot study exploring the usability of the prototype. Each therapist attended two sessions of one hour each to test and evaluate the proposed system. Feedback about the device was obtained through an administered questionnaire and combined with quantitative data. Results: Seven of the nine questions regar-ding the haptic exercise device scored higher than 3.0 (somewhat good) out of 4.0 (good). The postural sensors detected 93 of 96 (97%) therapistsimulated abnormal postures and correctly ignored 90 of 96 (94%) of normal postures. The elbow stimulation device had a score lower than 2.5 (neutral) for all as-pects that were surveyed, however the therapists felt the rehabilitation system was sufficient for use without the elbow stimulation device. Conclusion: All eight therapists felt the exercise platform could be a good tool to use in upperlimb rehabilitation as the prototype was considered to be generally well de-signed and capable of delivering reaching task therapy. The next stage of this project is to proceed to clinical trials with stroke patients.

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Robotic lower limb exoskeletons that can alter joint mechanical power output are novel tools for studying the relationship between the mechanics and energetics of human locomotion. We built pneumatically powered ankle exoskeletons controlled by the user’s own soleus electromyography (i.e. proportional myoelectric control) to determine whether mechanical assistance at the ankle joint could reduce the metabolic cost of level, steady-speed human walking. We hypothesized that subjects would reduce their net metabolic power in proportion to the average positive mechanical power delivered by the bilateral ankle exoskeletons. Nine healthy individuals completed three 30 min sessions walking at 1.25 m s–1 while wearing the exoskeletons. Over the three sessions, subjects’ net metabolic energy expenditure during powered walking progressed from +7% to –10% of that during unpowered walking. With practice, subjects significantly reduced soleus muscle activity (by ∼28% root mean square EMG, P<0.0001) and negative exoskeleton mechanical power (–0.09 W kg–1 at the beginning of session 1 and –0.03 W kg–1 at the end of session 3; P=0.005). Ankle joint kinematics returned to similar patterns to those observed during unpowered walking. At the end of the third session, the powered exoskeletons delivered ∼63% of the average ankle joint positive mechanical power and ∼22% of the total positive mechanical power generated by all of the joints summed (ankle, knee and hip) during unpowered walking. Decreases in total joint positive mechanical power due to powered ankle assistance (∼22%) were not proportional to reductions in net metabolic power (∼10%). The `apparent efficiency’ of the ankle joint muscle–tendon system during human walking (∼0.61) was much greater than reported values of the `muscular efficiency’ of positive mechanical work for human muscle (∼0.10–0.34). High ankle joint `apparent efficiency’ suggests that recoiling Achilles’ tendon contributes a significant amount of ankle joint positive power during the push-off phase of walking in humans.

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The present invention features a rapid fire rapid response power conversion system comprising (a) a chamber having at least one fluid port configured to supply combustible fluid to the chamber, and an out-take port; (b) a compressor for supplying compressed combustible fuel to the chamber at a variable pressure to at least partially facilitate combustion therein; (c) a controller for initiating and controlling a combustion of the combustible fluid in a combustion portion of the chamber to generate energy; (d) a rapid response component in fluid communication with the chamber and situated adjacent the combustion portion of the chamber, wherein the rapid response component is configured to draw an optimized portion of the energy generated from the combustion and to convert this optimized portion of energy into kinetic energy; and (e) a dynamic mass structure situated between the rapid response component and an energy transfer component and allowing the rapid response component and the energy transfer component to be independent of one another, wherein the dynamic mass structure is configured to receive and store the kinetic energy from the rapid response component upon being acted upon by the rapid response component, wherein the dynamic mass structure is displaced a pre-determined distance and at a given velocity such that it is caused to impact the energy transfer component, thereby transferring substantially all of the kinetic energy stored therein into the energy transfer component. The transfer of stored kinetic energy into the energy transfer component by the dynamic mass structure effectively causes the energy transfer component to displace, wherein the displacement is used to perform work used to power the device or system operable with the energy transfer component.

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A motor that delivers high force linear motion or high torque rotary motion to a moving element. The motor may include a driving brake, a driver, a holding brake and a flexible moving element. Operation of the motor may involve activating the holding brake, activating the driver to flex the moving element, activating the holding brake to maintain the position of a portion of the moving element, releasing the driving brake, and restoring the moving element to an unflexed position. The elements are arranged to provide linear motion, belt-driven rotary motion, or directly-coupled rotary motion using brakes and drivers arranged in linear or circular fashion. Drivers may be linear or rotary actuators or motors based on electrostatic, piezoelectric, magnetic, or electrostrictive properties. The brakes may be applied through electrostatic forces, magnetic forces, or mechanical gears engaged with a linear or rotary driving mechanism.

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(EN)A body-worn motion assisting device (1) comprises a shoulder joint mechanism (5) for assisting the user to move a shoulder joint, an elbow joint mechanism (6) for assisting the user to move an elbow joint, and a control unit (100) having a control circuit for controlling a drive unit (11) of the shoulder joint mechanism (5) and an elbow joint mechanism (6). The control unit (100) controls the drive unit (11) according to the physical quantities and biosignal detected by an angle sensor, a torque sensor, and a biosignal sensor. A control section of the drive unit (11) includes a motor monitoring block for monitoring the operation state of a motor and a motor control block for limiting the drive signal sent to the motor depending on the results of monitoring by the motor monitoring block so that the motor does not become under overload.
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