Robotics in rehabilitation provides considerable opportunities to improve the quality of life for persons with disabilities. Computerized and Virtual Environment (VE) training systems for persons with disabilities, many of which utilize the haptic feedback, have gained increasing acceptance in the recent years. Our methodology here is based on creating virtual environments connected to a haptic interface as an input device. This robotic setup introduces the advantages of the haptic rendering features in the environment and also provides tactile feedback to the patients. This thesis aims to demonstrate the efficacy of assistance function algorithms in rehabilitation robotics in virtual environments. Assist functions are used to map limited human input to motions required to perform complex tasks. The purpose is to train individuals in task-oriented applications to insure that they can be incorporated into the workplace. Further, Hidden Markov Model (HMM) based motion recognition and skill learning are used for improving the skill levels of the users. For the Hidden Markov Model based motion recognition, the user’s motion intention is combined with environment information to apply an appropriate assistance function. We used this algorithm to perform a commonly used vocational therapy test referred to as the box and the blocks test. The Hidden Markov Model based skill approach can be used for learning human skill and transferring the skill to persons with disabilities. A relatively complex task of moving along a labyrinth is chosen as the task to be modeled by HMM. This kind of training allows a person with disability to learn the skill and improve it through practice. Its application to motion therapy system using a haptic interface helps in improving their motion control capabilities, tremor reduction and upper limb coordination. The results obtained from all the tests demonstrated that various forms of assistance provided reduced the execution times and increased the motion performance in chosen tasks. Two persons with disabilities volunteered to perform the above tasks and both of the disabled subjects expressed an interest and satisfaction with the philosophy behind these concepts.

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This Paper describes the design of the ESA Human Arm Exoskeleton, which has been developed to enable force-feedback telemanipulations with redundant robotic arms. It is described, how several shortcomings of previous telemanipulation systems were eradicated, to meet the system requirements for a lightweight, easy wearable and comfortable system. The patented novelties towards prior arm exoske-letons are enlightened, and the methodology is shown, according to which the system was designed. The prototype, which has been developed at ESTEC is described in detail, outlining the special features of the design.

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There are numerous applications of VR simulation re-quiring the grasping and manipulation of virtual objects. Standard-use haptic interfaces (e.g. Virtuose 6D, PHANToM) allow only a limited level of realism, as grasping is approximated through a metaphor (e.g. pressing a button for grasping an object). Existing hand exoskeletons have also certain drawbacks (e.g. feedback only for finger flexion, limited finger workspace etc.). The work presented in this paper introdu-ces a hand force exoskeleton that allows full finger flexion and extension and applies bi-directional feed-back. It has 3dof at the index finger and 4 at the thumb. The system is actuated by DC motors and cable transmissions are used. It has been designed for use in conjunction with Virtuose 6D, a commercial 6dof haptic arm, in order to allow the simulation of external forces (gravity, contact reaction forces, etc.).

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This article describes the architecture of the «Museum of Pure Form», a virtual reality system where the user can interact, through the senses of touch and sight, with digital models of 3D art forms and sculptures. Two different realizations of «Museum of Pure Form» systems are currently being developed at PERCRO, Pisa, Italy. In one realization “The Museum of Pure Form” is conceived as a system placed inside several museums and art galleries around Europe and made available to people visiting such institutions. In the second realization the system will be placed and tested inside a CAVE environment. Considerations on technological aspects concerning the implementation of a virtual en-vironment endowed with haptic feedback for cultural heritage applications are reported throughout the paper.

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Millions of people in the U.S. currently require rehabilitation therapy due to neurologic injury and disease. In the case of stroke alone, there are approximately 600,000 new survivors each year, and over two million survivors with chronic movement deficits. Recent evidence suggests that intensive therapy improves movement recovery. However, such therapy is expensive because it relies on individualized interaction with rehabilitation therapists. The type and quality of therapy also varies greatly between clinics and therapists. Little technology is available to assist patients in practicing therapy on their own. Therapy techniques that require expert feedback or that incorporate manual manipulation of the patient’s limbs are often inaccessible once formal therapy is discontinued.

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