A Touch Panel for Presenting Softness with Visuo-Haptic Interaction

Abstract

This paper proposes a system capable of presenting softness using a touch panel. Many studies of touch panel-based haptic displays have developed methods for manipulating macro-roughness (shape), fine-roughness (texture), and friction. On the contrary, few studies have examined the sensation of softness. One reason for this is that to represent the spring constant of the object material, it becomes necessary to present a reaction force in the vertical direction, and this requires a large-scale device to move the surface up and down, or a device attached to the finger, both of which degrade the touch panel experience. To tackle this issue, we propose and have developed a system that can express softness not only visually but also haptically using a motor-driven film covering the touch panel to present a tangential force to the finger and with a simple visual shadow effect. In addition, we used the system to evaluate the subjective softness and confirmed the visual and haptic modulation with a realistic 3D image and a 2D image.