Developing an intelligent robotic arm for stroke rehabilitation

Arm impairments in patients post stroke involve the shoulder, elbow and wrist simultaneously. Patients may develop spasticity and reduced range of motion (ROM) at the multiple joints with abnormal couplings between the multiple joints and between the multiple degrees of freedom (DOF). They may lose independent control of individual joints and coordination among the joints. This project is aimed at developing a whole arm intelligent rehabilitation robot capable of controlling the shoulder, elbow, and wrist individually and simultaneously while allowing trunk motions, with the following integrated features: 1) it has unique diagnostic capabilities to determine which joints and which DOFs have significant changes in the neuromechanical properties, which joints lose independent control, what are the abnormal couplings, and whether the problem is due to changes in passive muscle properties or active control capabilities; 2) based on the diagnosis, it stretches the spastic / deformed joints forcefully under intelligent control to loosen up the specific stiff joints/DOFs; 3) with the stiff joints loosened up, the patients practice voluntary functional movements with assistance from the robot to regain/improve their motor control capability; and 4) the outcome is evaluated quantitatively at the levels of individual joints, multiple joints/DOFs, and the whole arm.