Quantitative analysis of surface textures created by MEMS tactile display using microfabricated tactile samples

This paper reports quantification of virtual surface textures produced by the MEMS-based tactile display. Tactile display consists of large displacement MEMS actuator array which is composed of piezoelectric actuators and hydraulic displacement amplification mechanism (HDAM) for large displacement to stimulate human tactile receptors. Tactile display can provide various surface textures such as 'rough' 'soft' 'elastic' etc. to fingertip by controlling the voltages, the vibration frequencies and the time of actuator's driving time. In previous work, we proved that tactile display could create smooth and rough textures by controlling the actuator's parameters. In this study, to quantify tactile feelings virtually produced by the MEMS tactile display, we newly propose 'Sample comparison method'. In this method, subjects require to compare between the virtual surface texture and tactile samples and select the sample most similar to displayed tactile feeling. In this paper, we firstly conducted comparing experiment using unprocessed samples to investigate what kind of surface characteristics can be controlled on the tactile display. Then, we experimented using microfabricated tactile samples to quantify the tactile feelings. At last, we successfully show the specific characteristics of surfaces virtually created by the MEMS tactile display.