A Novel Silicon Based Tactile Sensor with Fluid Encapsulated in the Cover Layer for Prosthetic Hand

Tactile sensing is indispensable for prosthetic hand to obtain information about contact forces and thus improve grasp stability. To reduce the burden of the hand's control and data acquisition (DAQ) system, we have developed a simple silicon-based tactile sensor containing a small number of sensing elements and owning large active sensory area in our previous work. In this paper, we incorporate a novel cover layer containing fluid in the sensor design to improve the uniformity of sensitivity from point to point in the whole receptive field. Experimental results show that with the cover layer, the normalized sensitivities of the tactile sensor are 1, 0.89151, 0.87736, and 0.82075 for four different indenting locations, which are 0, 1, 2 and 3 mm away from the center of the top surface, respectively. While without the cover layer, the normalized sensitivities of the tactile sensor are just 1, 0.8055, 0.42283, and 0.24101 for the four indentation locations, respectively.