Micro Capacitive Tactile Sensor for Contact Loads

This paper presents a high sensitivity micro capacitive tactile sensor that can detect normal forces which is fabricated using deep reactive ion etching (DRIE) bulk silicon micromachining. The tactile sensor consists of a force transmission plate, a symmetric suspension system, and comb electrodes. The sensing character is based on the changes of capacitance between coplanar sense electrodes and it can reach the aim of large sensing range. High sensitivity is achieved by using the high aspect ratio comb electrodes with narrow comb gaps and large overlap areas. In this paper, the sensor structure is designed, the capacitance variation of the proposed device is analyzed, and the finite element analysis of mechanical behavior of the structures is performed.