Medical robots have a strong presence in the medical field. In general, therapeutic robots are divided into two main groups: replacement robots and healing robots. The healing robot or rehabilitation robot is responsible for repairing the injured body. The ankle is prone to injury, and the injury interferes with the natural movement of the sole, so ankle rehabilitation exercises are needed. The platform is used to move patients' ankles and facilitate the treatment of torsion. In this project, a 3-RPS parallel robot is selected, and the mechanism required to produce its motion is designed. The homogeneous transformations of the leg and the robot, the inverse kinematic equations of the robot and its physical constraints are extracted. The optimization problem is done to select the maximum base length of the robot. The linear and rotational velocity equations of the moving plane are obtained. After designing the path, the Jacobin matrix and the robot singularity are discussed. Relationships The extracted robot dynamics and generalized forces and actuators are obtained. Suitable parts for making the device are selected, taking into account the design considerations, and the robot is designed with SolidWorks software. The parameters of the quantification robot, the graphs obtained from the relations are extracted, and their behavioral pattern is examined. Finally, the maximum power of the motors is calculated to move the device. Keywords: parallel robot, ankle rehabilitation, 3-RPS robot, platform robot