HairTouch: Providing Stiffness, Roughness and Surface Height Differences Using Reconfigurable Brush Hairs on a VR Controller

ABSTRACT Tactile feedback is widely used to enhance realism in virtual reality (VR). When touching virtual objects, stiffness and roughness are common and obvious factors perceived by the users. Furthermore, when touching a surface with complicated surface structure, differences from not only stiffness and roughness but also surface height are crucial. To integrate these factors, we propose a pin-based handheld device, HairTouch, to provide stiffness differences, roughness differences, surface height differences and their combinations. HairTouch consists of two pins for the two finger segments close to the index fingertip, respectively. By controlling brush hairs’ length and bending direction to change the hairs’ elasticity and hair tip direction, each pin renders various stiffness and roughness, respectively. By further independently controlling the hairs’ configuration and pins’ height, versatile stiffness, roughness and surface height differences are achieved. We conducted a perception study to realize users’ distinguishability of stiffness and roughness on each of the segments. Based on the results, we performed a VR experience study to verify that the tactile feedback from HairTouch enhances VR realism.