Expression of 2DOF fingertip traction with 1DOF lateral skin stretch

Abstract

To reproduce the sensation of rubbing on a surface, we need to laterally stretch the skin of the fingertip with two degrees of freedom (2DOF). Unfortunately, it is difficult to develop a compact 2DOF device for the fingertip because at least two actuators are required. However, if we can perceive the rubbing sensation regardless of the skin stretching direction, a device with 1DOF is sufficient. This study used a lateral skin deforming device with 1DOF, and evaluated the realism of the sensation. We found that even when the direction of skin stretch was opposite or perpendicular to the finger movement, users still perceived it as natural.