Integrated control method for power-assisted rehabilitation: Ellipsoid regression and impedance control

This paper proposes an integrated control method including learning with an ellipsoid function and impedance controller for rehabilitation using power-assisted robotic devices. The proposed controller consists of two parts of a primary algorithm, which are ellipsoid regression method for re-designing trajectory and impedance controller with pseudo mass/inertia. The ellipsoid regression method generates reference impedance profiles though acquiring motion and force trajectories during rehabilitation tasks assisted by therapists. The assisted force is controlled by impedance controller during execution of rehabilitation task using a concept of pseudo mass/inertia. The proposed method offers the power-assisted rehabilitation as guided by therapist, without consistent help from the therapist or other assisters. The proposed control method is validated by experiments throughout a 2-DOF rehabilitation robot, KULEX-2DOF(KIST Upper Limb Exoskeleton - 2DOF).