Haptic matching of directional force and skin stretch feedback cues

This paper presents a two degree-of-freedom (2-DOF) force feedback joystick with a 2-DOF skin stretch feedback device integrated into the top of its handle (where the user rests his/her thumb). An experiment is conducted to better understand how users interpret directional information from force and skin stretch cues. Results show that users exhibit significantly greater accuracy when responding to force cues, but have significantly greater precision when responding to skin stretch cues. Precision is further improved when these cue types are combined. Integrating skin stretch and low-magnitude force cues in this manner shows promise for applications where force information is beneficial, but cannot be presented due to the risk of creating feedback instabilities. Hence skin stretch feedback could be used to supplement lower, non-destabilizing levels of force feedback, or to augment underpowered force feedback systems. Skin stretch may also be used as a lower cost, more compact substitute to force feedback.