Development of tactile sensor with functions of contact force and thermal sensing for attachment to intelligent robot finger tip

This paper describes the design and fabrication of a flexible tactile sensor using polymer micromachining technologies, which can measure the three-component force and temperature caused by thermal conductivity. The tactile sensor is comprised of sixteen micro force sensors with 4 times 4 arrays and its size being 13 mm times 18 mm. Each micro force sensor has a square membrane, and its force capacity is 0.6 N in the three axis directions. The normal and shear forces are obtained from four thin-film metal strain gauges embedded in a polyimide thin-film membrane. The optimal positions of the strain gauges are determined by the strain distribution obtained form finite element analysis. In order to acquire force and temperature signals simultaneously from the fabricated tactile sensor, we fabricated a PCB based on multiplexer, operational amplifier and microprocessor with CAN network function. The fabricated flexible tactile sensor was evaluated from the evaluation apparatus. Also we confirmed that the sensor has the function of temperature sensing throughout feasibility test such as contacting with some objects.