Fig. 3

The representative tracking trajectories in the wrist (W) and the elbow (E) tracking phases, when giving different assistive schemes, i.e., 1) no assistance from either the robot or the NMES (R0N0), 2) assistance from both the robot and the NMES (R100N100), 3) assistance from the robot only (R100N0), and 4) assistance from the NMES only (R0N100). The blue lines are for the target positions and the red lines are for the actual positions