Characterization of the Repeatability and Sensitivity of the Quantum Tunneling Composites

The fast development and expansion of the robotics field and biomedical application in the last several decades have generated a growing interest in the flexible tactile sensing solutions. In this experimental study, the flexible sensor material is characterized by utilizing piezoresistive mechanism based on quantum tunneling composites. With attention to pressure-sensitivity of this composite, the effect of nickel powder filler ratio and sample thickness are systematically investigated. Electrical resistance and sensitivity of the QTC depend on the concentration and shape of nickel powder. There is a lower threshold of nickel powder concentration for the QTC to be sensitive under 500N force applied. With increasing nickel powder concentration, an elasticity of the QTC decreases, but stability, reproducibility, and sensitivity of the composite improved.