Feasibility of a One Degree-of-Freedom Linear Robot for Bed-Bound Stroke Rehabilitation

A 1DOF lower limb rehabilitation robot is presented for delivering leg extension therapy to bed-bound stroke patients. Such a compact and minimal system may be beneficial in terms of compatibility with pre-existing hospital equipment, ease-of-use, safety, and cost. A set of design criteria was created based on the literature and on previous field work at a local hospital. The device uses admittance control to apply assistive or resistive forces, and can also use haptic feedback to increase user engagement. A pilot study on six healthy participants was used to determine the feasibility of such a minimal system in administering assistance or resistance through the leg extension exercise. Results indicate that a single DOF is capable of decreasing trajectory error with assistance and increasing user effort with resistance. Observations confirm that the minimal system is effective; however, extending the robot with additional DOFs so that it can target multiple bed-bound exercises may help to increase therapy duration.