Omnidirectional Tactile Profiling Using a Deformable Pressure Sensor Array Based on Localized Piezoresistivity

Abstract With the recent progress of stretchable electronics, artificial tactile sensors pursue to imitate the human tactile system that is deformable and omnidirectional without signal interference. Although deformable tactile sensors without signal interference are demonstrated previously by using stretchable transistors or diodes, achieving omnidirectional tactility is very limited. It is because covering the 3D surfaces of fingers and hands with a sensor requests the structural simplicity and the customized shape design of the sensor. Here, a simple piezoresistive sensor without using the transistors or diodes is developed. The sensor is based on the localized piezoresistivity realized by creating the elastic resistive pixels that are laterally insulating with neighboring pixels. It can be wrapped on a finger and provide the pressure profiles and the spatial deformation of the substrate when multiple mechanical stimuli are applied from arbitrary directions. Based on this omnidirectional tactility, the blind contact recognition of objects that are piled up in a box is demonstrated.