Asymmetric fan-shape-electrode for high-angle-detection-accuracy tactile sensor

This paper reports an up to 95.9% angle detection accuracy enhancement for capacitive tactile sensors, which entails asymmetric and intentionally shifted electrodes. The rotational shift between two electrodes of a capacitor that greatly contributed to angle detection errors was theoretically analyzed and examined by experiments with simulations. The asymmetric electrodes containing one fan- and one square-shape in capacitors reduced unexpected and rotational-shift induced errors, by keeping the same overlap area of the electrodes. The minimal angle detection resolution was improved from 5.8° to 0.3°, making the tactile sensor practical and reliable in artificial skins.