High resolution silicon MEMS tactile sensors for measurement of fingertip sensation

In this paper, novel semiconductor silicon based MEMS tactile sensors for measurement of fingertip sensation and their high resolution detection ability of surface texture are presented. All the device structure is made from silicon single crystal layer on SOI wafer. Two-axis movements of needle-like contactor tip are independently detected by the two independent suspensions. The movement is precisely detected by integrated strain detection circuits. Obtained results from the sensors were carefully analyzed with statistical analysis and FFT, and various objective facts have been made clear. For example, the rougher the feel texture of a paper surface, the lower the mutual relation between the time-domain waveform of surface micro roughness and the corresponding instantaneous frictional force. This is an example of never known knowledge about surface feel of touch, and a lot of information to quantify the sense of touch has been extracted using the tactile sensor in this study.