The invention relates to a parallel three-degree-of-freedom
ankle joint
rehabilitation robot. The
ankle joint
rehabilitation robot comprises an adjustable pedal, a movable platform, an inner
branch chain, a middle
branch chain, an outer
branch chain, first belt wheel tensioning apparatus, second belt wheel tensioning apparatus, third belt wheel tensioning apparatus and a static platform. The wholerobot is a 3-RRS parallel mechanism, the three branch chains are coaxially installed on a stepped shaft of the static platform, the middles of the branch chains are connected through middle revolutepairs, the
tail ends of the branch chains are connected with the movable platform through ball pairs, the axes of base shaft revolute pairs of the three branch chains coincide with a common axis, theaxes of the middle revolute pairs of the three branch chains are perpendicular to one another in a space, the common axis of the three branch chains at the positions of the base shaft revolute pairs and the axes of the middle revolute pairs intersect at a fixed point in the space, and the movable platform has
three degrees of freedom rotated around the fixed point. The adjustable pedal is installed on the movable platform, the situation that the
ankle joint rotating center coincides with the
robot space fixed point is guaranteed by adjusting a height of the adjustable pedal relative to the movable platform and a length of the pedal, and thereby a patient can be helped to do three
rehabilitation exercises of back stretching /
toe bending, inversion / eversion and inward rotation / outward rotation, or composite rehabilitation exercises. The ankle joint
rehabilitation robot is compact in structure, high in control precision, safe, reliable and capable of accurately meeting rehabilitation requirements of patients with the ankle
joint injury.