Omni-Directional Tactile Profiling Using a Deformable Pressure Sensor Array Based on Localized Piezoresistivity

The E-skin devices have found a variety of potential applications such as skin-attachable or implantable healthcare sensors, wearable haptic devices, prosthetics, and artificial skin for robots. Since the pressure sensor matrix is expected to provide tactile intelligence to robot, the interest has been rapidly increasing with the recent advent of humonoids. The tactile intelligence requires high deformability, minimized signal interference, perception of various types of stimuli and omni-directional sensing of stimuli at multiple points (tactile profiling). There have been advances made in the deformability and minimized signal interference. Unfortunately, the omnidirectional deformable tactile sensor for tactile profiling has not yet been reported. In this study, we developed a localized piezo-resistive deformable sensing layer and demonstrated a deformable omni-directional tactile sensor matrix. With the negligible signal interference between the pixels, the sensor showed a linear sensing in a broad pressure range (0.41 – 200 kPa) and was not affected under deformation. Furthermore, this deformable sensor matrix could be wrapped on a finger and provide the pressure distribution upon multiple mechanical stimuli from arbitrary directions. Also, we demonstrate the blind contact recognition of objects that are piled up in a box.