Novel tactile sensors manufactured by carbon microcoils (CMC)

The carbon microcoils (CMC) with a high elasticity and coiling-chirality was prepared by the Ni catalyzed pyrolysis of acetylene containing a small amount of H2S. The morphology and their mechanical and electrical properties, especially tactile sensing properties, were examined. It was found that superelastic CMC, which could be extended and contracted to more than 15 times of the original coil length, could be obtained by controlling the reaction conditions. The extension of CMC was very high sensitive for applied load, and could be detected very low applied load of milligram orders. The electrical resistivity (R) of the CMC increased with the extension and decreased with the contraction. Inductance (L) and capacitance (C) of CMC/polysilicone composites extensively changed with the extension and contraction of the composite under various touching modes, such as pressing, picking, stretching, etc. It was supposed that these tactile sensing properties were affected by novel LCR composite hybrid resonance.