A portable low-cost 3D-printed wrist rehabilitation robot: Design and development

This article proposes a two-degrees-of-freedom robot for wrist rehabilitation, referred to as MOCH. The MOCH mechanism comprises a remote center of motion (RCM) mechanism with a rotation center outside of the robot structure. When the patient holds the robot end-effector, coinciding the RCM of the robot with the rotation axis of the wrist allows pure rotational motion of the hand. As the rotation point lies out of the robot structure, there is less risk of interference between the patient and the robot. Furthermore, MOCH benefits a novel actuation that enables the actuators to be grounded, reducing the inertia and the size of the robot, and eliminating difficulties with feeding power to actuators on moving linkages. The optimal design of MOCH is provided considering the mechanical criteria and requirements of the wrist rehabilitation robot. Based on the proposed design, a prototype of the robot is developed with a mass of 1.3 kg using 3D printing. To validate the efficacy of MOCH in practice, a trajectory tracking control strategy is implemented for passive wrist rehabilitation.

Automated summary

This article proposes a two-degrees-of-freedom robot called MOCH for wrist rehabilitation. The MOCH mechanism includes a remote center of motion (RCM) mechanism with a rotation center outside of the robot structure. By coinciding the RCM of the robot with the rotation axis of the wrist, the patient can achieve pure rotational motion of the hand. MOCH's design takes into account the mechanical criteria and requirements of the wrist rehabilitation robot, and it uses a novel actuation to reduce inertia and size.