Upper-Limb Rehabilitation Robot: A Measure of Intent Detection for Robot Aided Active Therapy Exercise

Abstract

<h3>Research Objectives</h3> In robot-aided rehabilitation of post-stroke patients with upper limb impairment, robotic device must allow patient's effort in performing exercises. To estimate such effort, user's force exerted on robotic device can be used during active exercises. To validate use of force exerted by user/wearer by comparing with EMG signals as a measure of intent detection in robot-aided active therapy on rehabilitation robot, in this research, user's interactive force with robot was measured and compared with user's muscle activity (EMG) during elbow flexion-extension performed by an upper-limb rehabilitation robot (u-Rob). This physiological measure will help design rehab robot centering patient's need and level of impairment. Furthermore, it can give an indication of spastic behavior during rehab exercises. <h3>Design</h3> Experimental study of robot-aided therapy to observe force values with EMG values, leading to use force as a measure of intent detection. <h3>Setting</h3> Protocol: Elbow flexion/extension (0-120 deg) motion. Experiments (passive and active therapy exercise, five trials/exercise) were conducted with healthy subject in seated position wearing the robot. <h3>Participants</h3> 2 healthy males and 1 healthy female. <h3>Interventions</h3> Elbow flexion/extension (0-120 deg) motion. Experiments (passive and active therapy exercise, five trials) were conducted subject in seated position wearing the robot. <h3>Main Outcome Measures</h3> Force exerted by the participant and participant's EMG <h3>Results</h3> Significant amount of force is exerted during active exercise and significant amount of EMG activity is observed during active exercise. Besides, looking at the torque, it is seen that during active rehab exercise, robot has to contribute lesser torque than in passive exercise. <h3>Conclusions</h3> User-robot interactive forcesdetected by sensor can be used as a measure of intent detection during robot-aided active exercise. Moreover, measured forces can also be observed from muscle activity. It may give an idea of subject's spastic behavior. <h3>Author(s) Disclosures</h3> N/A.