Rehabilitation robotics specializes in designing machines, such as exoskeletons, which can be utilized to restore function in patients recovering from physical trauma. The proposed Assistive Rehabilitation Arm Orthosis (A.R.A.O.) is designed to restore function and rehabilitate patients suffering from muscular diseases as well as mild-stroke. Clinical studies have shown that task-based repetitive training can improve motor abilities and enhance functional performance in those recovering from stroke. The proposed design improves on the popular four bar linkage systems used in many modern orthoses by incorporating a dynamic feedback system that actuates elastic elements, allowing users to lift heavier objects, while still remaining portable. The dynamic feedback system incorporates force-sensing resistors in conjunction with a linear actuator to vary the tension in the tension bands. The device not only allows patients to perform day-to-day lifting tasks but also has the potential for use in rehabilitation.

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This research aims to develop a portable haptic master hand with 20 degrees of freedom (DOF). Master hands are used as haptic interfaces in master-slave systems. A masterslave system consists of a haptic interface that communicates with a virtual world or an end-effector for tele-operation, such as a robot hand. The thumb and fingers are usually modeled as a serial linkage mechanism with 4 DOF. So far, no 20 DOF master hands are developed that can exert perpendicular forces on the finger phalanges during the complete flexion and extension motion. In this paper, the design and development of a portable 4 DOF haptic interface for the index finger is presented. The concept utilizes a mechanical tape brake at the rolling-link mechanism (RLM) for passive force feedback. The systematic Pahl and Beitz design approach is used as an iterative design method. Important design requirements are; perpendicular forces on the finger phalanges, low friction mechanism, easy to control, no backlash, high backdrivability and lightweight

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After a stroke, many survivors have impaired motor function. Robotic rehabilitation techniques have emerged to provide a repetitive, activity-based therapy at potentially lower cost than conventional methods. Many patients exhibit intrinsic resistance to hand extension in the form of spasticity and/or hypertonia. We have developed a therapy program using the Hand ExoskeletonRehabilitation Robot (HEXORR) that is capable of compensating for tone to assist patients in opening the paretic hand. The system can move the user’s hand, assist movement, allow free movement, or restrict movement to allow static force production. These options combine with an interactive virtual reality game to enhance user motivation. Four chronic stroke subjects received 18 sessions of robot therapy as well as pre and post evaluation sessions. All subjects showed at least modest gains in active finger range of motion (ROM) measured in the robot, and all but one subject had gains in active thumb ROM. Most of these gains carried over to ROM gains outside of the robot. The clinical measures (Fugl-Meyer, Box-and-Blocks) showed clear improvements in two subjects and mixed results in two subjects. Overall, the robot therapy was well received by subjects and shows promising results. We conclude HEXORR therapy is best suited for patients with mild-moderate tone and at least minimal extension.

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In this paper, a grip amplified glove using pneumatic artificial rubber muscles (PARMs) which are covered with a exoskeletonstructure is developed. A bi-articular mechanism with a PARM that is suitable for bending finger is realized. The glove has totally 10 DOFs consist of four units. To achieve power-assist motion properly, the PI control, which is based on the pressure value from the balloon sensor, is performed. This sensor makes the applied part free from electricity. To evaluate the validity of glove, the skin surface electromyography (EMG) signals of muscles are measured during grasping. These results demonstrate that the effectiveness of the power amplified glove.

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One of the key requirements for a Virtual Reality system is the multimodal, real-time interaction between the human operator and a computer simulated and animated environment. This paper investigates problems related particularly to the haptic interaction between the human operator and a virtual environment. The work presented here focuses on two issues: 1) the synthesis of whole-hand kinesthetic feedback, based on the application of forces (torques) on individual phalanges (joints) of the human hand, and 2) the experimental evaluation of this haptic feedback system, in terms of human haptic perception of virtual physical properties (such as the weight of a virtual manipulated object), using psychophysical methods. The proposed kinesthetic feedback methodology is based on the solution of a generalized force distribution problem for the human hand during virtual manipulation tasks. The solution is computationally efficient and has been experimentally implemented using an exoskeleton force-feedback glove. A series of experiments is reported concerning the perception of weight of manipulated virtual objects and the obtained results demonstrate the feasibility of the concept. Issues related to the use of sensory substitution techniques for the application of haptic feedback on the human hand are also discussed.

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