Capacitive Tactile Sensor Using Mutual Capacitance Sensing Method for Increased Resolution

As robots move toward more complex environments, imbuing them with a sense of touch similar to humans becomes increasingly important. To fulfill that goal, there has been significant research conducted in the past few decades to develop a tactile sensor that matches human level touch capabilities. Recently, the progress in capacitive touch screens has made capacitive sensing a very appealing option for such a sensor, and therefore many research groups have proposed novel designs of tactile sensors based on capacitive technologies. This technology has the advantage of generating a predictable sensor response with a high degree of sensitivity, but has the drawback of a limited spatial resolution. This paper shows how using mutual capacitance in combination with a microstructured dielectric can lead to a very sensitive sensor that also possesses a high spatial resolution. The response of the sensor in relation to its various components is explored in order to fully comprehend the physical principles of the sensing mechanism and generate a predictable output.