Design and Kinematics Analysis of Parallel Robots for Ankle Rehabilitation

Ankle joint injury is a common athletics injury in clinic. It can be treated in a medical way, besides, rehabilitation exercises are needed, sufferers can regain the ankle joint´s function to the greatest extent and enhance the proprioception. In this paper, a medical treatment robot is proposed for ankle joint rehabilitation exercises, in which the 3-RSS/S parallel mechanism is adopted based on the ankle joint´s movements. The mechanical design is described and the inverse kinematic is derived, as a result, the Jacobian matrix is obtained. Furthermore, a reality model of the robot is built by UG and simulated under the ADMS environment. It shows the design can meet the needs of ankle joint rehabilitation movements. In order to validate these concepts, the first prototype is developed that driven by three torque motors and equipped with force sensor for sensing the interaction force between patient´s foot and robot. At last, the robot´s control system is presented in the paper