The device renders force feedback by tilting itself against the user’s will. It achieves this by stimulating muscle tissue in the user’s arm though the electrodes, triggering an involuntary contraction. This causes the user’s arms to tilt sideways and thus the device to tilt. In a videogame where the player's airplane is controlled by tilt (Figure 2), the involuntary tilting represents winds that threaten to derail the airplane. To stay on course, players counter the actuation using the force of their other arm (Figure 3). As we find in Study 2, players perceive this as force feedback.
The prototype is based on a medically compliant signal generator and use is pain-free.