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

Abstract

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.

Surface properties that can be displayed by a microelectromechanical system‐based mechanical tactile display

“…We summarise the obtained results in Table 2, which includes the results with respect to roughness and hardness from prior work [17, 18]. In this table, the number of ‘+’ symbols indicates the strength of the relationship and the ‘−’ symbol means the correlation is not significant.…”

“…However, the surfaces displayed by the tactile displays are virtual ones and cannot be measured by instruments. Therefore, in our prior work, we proposed a sample comparison method [17, 18], wherein the subjects were requested to select one of 18 samples that they considered most similar to the surface presented by the tactile display. The surfaces of the samples were thoroughly characterised and quantified by scientific instruments.…”