A Novel 3-UPU Parallel Ankle Rehabilitation Mechanism

Based on the analysis of existing ankle rehabilitation devices, a new ankle rehabilitation mechanism based on 3-UPU parallel mechanism is proposed in this paper. The mechanism has three degrees of freedom, and can achieve ankle pronation/supination, inversion/eversion, and stretch movement. The rotation axis of the mechanism can be adjusted according to the ankle height and the position of the movement axis of the human body. In this paper, the inverse kinematics and DOF of the mechanism are solved. According to the ankle rehabilitative requirements, the size of the mechanism is determined, and the workspace of the mechanism is further solved. Finally, the kinematics of the mechanism is simulated and verified by the prototype. Therefore, the rotation axis of the mechanism can match with the motion axis of the human ankle joint better and bring better rehabilitation effects to the patients.