This paper presents a design frame of a leg exoskeleton. The performance of an exoskeleton was analyzed by studying a model of a linear coupled 1-DOF human-exoskeleton system. The results showed that a low-impedance, anthropomorphic and well attached mechanical structure is benefit for the control of exoskeleton, and a direct force feedback control could also be implemented to further reduce the impedance. Three kinds of applied sensor interface were compared. A leg exoskeleton called ELEBOT was developed for validating control algorithm. The ELEBOT included four main parts: mechanical structure, hydraulic actuator, sensor and control system and power. The function of such a load-carrying robot is to reduce the injuries associated with the back and lower limbs after a long heavy walk. Experiment results with a simple force controller confirmed that ELEBOT could efficiently assist people walking with 30 kg payload now.

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This paper introduces a sensor suite framework for the partial automation of prosthetic arm control allowing high level control with a reduction of cognitive burden placed upon the user. Automation aims to replicate the hand eye co-ordination through the synergy of a virtual 7DOF arm prosthesis together with the development of a gaze tracking system. The interactions between elements of the suite are detailed and a selection of sensors implemented to control a simple simulation. Use of the novel tongue control system is used to provide discrete input to the system. Initial tests are made of of the system together with a users ability to learn to use the system with promising user feedback on ease of interaction and potential for reduced cognitive burden.

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In this work, we focus on iterative distributed model predictive control (DMPC) of large-scale nonlinear systems subject to asynchronous, delayed state feedback. The motivation for studying this control problem is the presence of asynchronous, delayed measurement samplings in chemical processes and the potential use of networked sensors and actuators in industrial process control applications to improve closed-loop performance. Under the assumption that there exist upper bounds on the time interval between two successive state measurements and on the maximum measurement delay, we design an iterative DMPC scheme for nonlinear systems via Lyapunov-based control techniques. Sufficient conditions under which the proposed distributed MPC design guarantees that the state of the closed-loop system is ultimately bounded in a region that contains the origin are provided. The theoretical results are illustrated through a catalytic alkylation of benzene process example.

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Background: Upper-extremity movement is limited in individuals with muscular weakness. This paper describes a novel, articulated upper-extremity orthosis, the Wilmington Robotic Exoskeleton (WREX), which helps people overcome this movement deficit.

Methods: This prospective, case-controlled study involved an ambulatory patient with arthrogryposis multiplex congenita and 2 nonambulatory patients with spinal muscular atrophy type II. The WREX uses elastic bands to negate the effects of gravity; it allows a person with neuromuscular weakness to move their arm in 3 dimensions. The WREX can be fixed on a brace for ambulatory patients and on the wheelchair for nonambulatory patients. Assessment was performed through motion analysis (with and without the WREX), clinical examination, and qualitative questionnaire.

Results: Motion analysis showed a marked improvement in upper-extremity function with the WREX. The questionnaire illustrated enhanced functionality with the WREX including self-feeding, fine motor control, and use of a television remote control. Enhanced functionality resulted in improved quality of life by increasing participation in school, raising self-esteem, and increasing social interaction. Two unexpected outcomes were increased security with trunk inclination and amelioration of the effects of contractures.

Conclusions: The WREX provided an increase in functionality and improved the quality of life of the patients. The device has become an integral part of the lives of the 3 patients.

Level of Evidence: Level III in Therapeutic Studies-Investigating the Results of Treatment.

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This paper describes an endoskeleton anthropomorphic biped robot design and construction. The endoskeleton structure is aimed for robot’s high power efficiency over its weight, but it demands unique structure and devices of the robot coping with the complexity. The gadgets newly developed for the robot such as a linear actuator, coupled link mechanism, inertia and Zero Moment Point(ZMP) sensors are described. The corresponding design procedure inevitably becomes sophisticated, so the powerful design tool to deal with this difficulty is utilized, and the way is explained. Feedback control scheme was established for its stable walking. Based on the outcome of the design, analysis, and simulation data, the actual robot was constructed and the paper shows its successful experimental results.

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