Novel tactile and nearness sensing properties of carbon microcoils (CMCs)

Carbon microcoils (CMCs) with 3D-helical/spiral conformations were embedded into various elastic matrices, such as polysilicone, elastic epoxy resin, etc., to produce CMC tactile and nearness micro-sensory elements. The sensing properties of the CMC sensor element (changes in electrical parameters under an applied load (pressure) or approaching substances) were examined. The sensing ability was obtained even for microelements of 0.1 X 0.1 X 0.1 mm³ or 0.05 mm thickness, and for a small added amount of 0.1 wt% CMCs in the matrix. The minimum detection pressure was ca.l Pa. Changes in the L, C, R or Z parameter were also observed by approximating a hand, heater, mobile phone, sound, etc. It was considered that the CMC sensor elements have high potential applications, such as tactile sensors for endoscopes, catheters, a manipulation sheet, or as the artificial skin with a high tactile sensing ability and/or as nearness sensors for humanoid robots, etc.