Fig. 2

The two rehabilitation games. a Shoulder Flexion Game (Game 1, left) and an experimenter holding the stylus of a haptic device to perform shoulder flexion and extension (right) to control the plane in Game 1 to move upward and downward to collect the coins moving horizontally in the game scene and b Shoulder Horizontal Abduction Game (Game 2, left) and an experimenter holding the stylus of a haptic device to perform shoulder horizontal abduction (right) to control the character on the ground to collect the coins falling from top to the ground