A tactile sensor using a graphene film formed by the reduced graphene oxide flakes and its detection of surface morphology

Abstract

To imitate tactile sensing for application to artificial skin, we propose a highly sensitive tactile sensor for a flexible architecture by introducing a film of the reduced graphene oxide flakes that significantly enhances the sensitivity for static and dynamic input forces. Its working pressure covers the human perception range due to interaction with touching events. In particular, high sensitivity (40.8 kPa(-1)) for the low pressure response allows the detection of internal pressure generated by muscle movement. Demonstrations are performed to monitor the motions of the finger and elbow through a sensor attached to human skin. In addition, detection of the dynamic pressure induced by an artificial fingerprint structure equipped on the sensor is tested and analyzed using different scan velocities (3-32.5 mm/s) to ensure the tactile sensing capability.