We have developed a new type of master hand to control a dexterous slave robot hand for telexistence. Our master hand has two features. One is a compact exoskeleton mechanism called “circuitous joint,” which covers wide workspace of an operator’s finger. Another is the encounter-type force feedback that enables unconstrained motion of the operator’s finger and natural contact sensation. In this paper, the mechanism and control method of our master hand are introduced and experimental master-slave finger control is conducted.

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A normal working hand is one of the most important features for independence in an individual’s life. The human dependence on fully functioning hands is highlighted most when these integral tools of the body are hindered in some way. The loss of hand function results in a severe compromise of the ability to feed and care for oneself, and limits one’s participation in work, social and family life (Scott and Peckham 1995). There are many injuries or conditions that can result in the loss of hand function. These include paralysis (from central or peripheral nerve injuries), swelling, joint stiffness, pain, burns, scarring or broken bones. For individuals recovering from such conditions, vigilant, appropriate and effective therapy of the hands can significantly improve the outcome of the healing process and the restoration of hand function (Hunter, Mackin et al. 1995). Prior to the prescription of appropriate therapy, comprehensive assessment of hand condition is necessary. Furthermore, ongoing assessment during the course of the applied therapy can ensure the treatment will continue to be appropriate and provide optimal benefits to the patient. In addition, during the recovery process and where no further improvements can be made to the hand, there are technologies available that can improve and function.

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In this paper we present a method to control a one-legged lower extre-mities orthosis by analyzing the current trajectory performed with the healthy leg and feeding a proper- if necessary phase-shifted — trajectory to the disabled leg encased in the orthosis. For this, a fast and simple modified version of the cross correlation is used. The algorithm works on multiple reference curves by minimizing the error between the reference and the current data by adaptively walking forward through the reference of the healthy leg and reporting back the reference values for the disabled leg. The proposed method will be part of a control system for an exoskeleton robot that should aid the wearer in everyday-life situations like walking, standing up and sitting down. The performance of the presented method was investigated on the leg movement in sagittal plane without contact to unknown obstacles.

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The prevalence of neurological diseases such as stro-ke, spinal cord injury and traumatic brain injury is increasing quickly in the industrialised societies. Although the benefit of the use of technology in rehabilitation and neurorehabilitation programs is prov-ed, the presence of mechatronic systems is still very low. This paper proposes a new lower limb exo-skeleton for gait rehabilitation in persons with neurological pathologies. Since potential users have very reduced mobility even to start common daily movements, the control of the exoskeleton has to be intention based. The estimation of the intention of the user is based on hip and knee angle, and the EMG signal is monitored for intention detection, control and neurofeedback aims. A novel approach of the EMG to force conversion in paraplegic patients is also described.

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Autonomous grasping in dynamic environments where the object the robot or both are moving is an increasingly common task in robotic applications This thesis describes an online trajectory planner a geometric controller which evaluates a nonlinear memoryless function to map the current object position and velocity into a desired robot pose If the robot tracks these set points it is guaranteed to match the object s velocity and acceleration on a specied grasp surface A planar simulation demonstrates that this paradigm performs favorably when compared with the traditional planning approach Since it does not depend on future state predictions no object model is required Without trajectory prediction the computational effort is drastically reduced allowing for higher controller speed and tracking feedback gains The geometric controller has been successfully implemented on the dof Sarcos Dextrous Arm In order to provide the critical local sensing just before robotenvironment contact this thesis reports on work in progress towards the development of a proximity sensing network located in a robots multingered gripper This network will form an integral part of a multistage sensing system with vision and tactile sensor pads Sensing information is passed on to geometric controller which provides a framework for general sensorbased control of robotic tasks

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