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

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Significant advances in meso-scale prototyping are enabling rigid, articulated, and actuated microrobotic structures. Here, an elegant manufacturing paradigm is employed for the creation of a biologically- inspired flapping-wing micro air vehicle with similar dimensions to Dipteran insects. A novel wing transmission system is presented which contains one actuated and two passive degrees of freedom. The design and fabrication are detailed and the performance of the resulting structure is elucidated highlighting two key metrics: the wing trajectory and the thrust generated.

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A «muscle suit» that will provide muscular support for the paralyzed or those otherwise unable to move unaided is being developed as a wearable robot. The muscle suit consists of a mechanical armor-type frame and McKibben artificial muscle. Using a new link mechanism for the shoulder joint which consists of two half-circle links with four universal joints in total mounted at both ends of each link, all motion for the upper limb has been realized. Applying the muscle suit to non-healthy people such as elderly people and/or disable one requires very high-level safety and usability, from the practical point of view. We then in the first place for the practical use, apply the muscle suit to the manual worker. In this paper, we introduce how we can apply the muscle suit for a manual worker.

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We propose a novel control method for lower- limb assist that produces a virtual modification of the mechanical impedance of the human limbs. This effect is accomplished through the use of an exoskeleton that displays active impedance. The proposed method is aimed at improving the dynamic response of the human limbs, while preserving the user’s control authority. Our goal is to use active-impedance exoskeleton control to improve the user’s agility of motion, for example by reducing the average time needed to complete a movement. Our control method has been implemented in a 1-DOF exoskeleton designed to assist human subjects performing knee flexions and extensions. In this paper we discuss an initial study on the effect of negative exoskeletondamping (a particular case of active-impedance control) on the subject’s time to complete a target-reaching motion. Experimental results show this effect to be statistically significant. On average, subjects were able to reduce the time to complete the motion by 16%.

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Stroke is the leading cause of long-term disability in the world. It causes chronic deficits, such as hemiparesis, especially prevalent in the distal upper extremities. An electro-mechanically driven hand orthosis has been developed to assess the potential thera-peutic use of such devices in rehabilitating hand function. A small Direct Current (DC) brushed motor is used as the main actuator, and a cable-driven glove connected to the motor shaft is the central component of the device. The orthosis control is achieved through a force feedback loop using a miniature load cell attached in series to the cable and control module. The later, generates Pulse Width Modulated (PWM) and direction signals required to drive the motor. The speed is determined by the duty cycle of the PWM signal while the direction by the status of a flag bit modified by a user-operated switch. A portable design was achieved by using a 6 V battery pack as the power supply. The device is ready for use in clinical trials with stroke survivor subjects as it has already been tested on healthy individuals with satisfactory per-formance.

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