Adaptive Potential Scanning for a Tomographic Tactile Sensor with High Spatio-Temporal Resolution

A tactile sensor with high spatio-temporal resolution will greatly contribute to improving the performance of object recognition and human interaction in robots. In addition, being able to switch between higher spatial and higher temporal resolution will allow for more versatile sensing. To realize such a sensor, this paper introduces a method of increasing the sensing electrodes and adaptively selecting the grounding conditions in a tomography based tactile sensor. Several types of grounding conditions are proposed and evaluated using spatio-temporal metrics. As a result, the grounding method based on the location of contact had a good balance of temporal resolution (1 ms) and spatial resolution (only 1.55 times larger than using all electrodes as grounding conditions). When reconstructing dynamic contact data, the proposed method was able to obtain a much higher detailed waveform compared to the conventional method. By using the proposed method as default and switching to other grounding methods depending on the purpose of sensing, a versatile tactile sensor with high spatio-temporal resolution can be made.