Mono-Structure Touch Sensor With Multi-Function For Discrimination of Material Properties

Abstract

This paper describes the development of a touch sensor which has a mono-structure, but has three kinds of sensing functions for discrimination of material properties. The proposed sensor is used to discriminate typical materials such as iron, aluminium, copper, bronze, gum, wood, acrylic resin, styrene foam and etc..
The sensor consists of two spiral metallic lines on a thin insulating substrate and has four terminals. When the two lines are used as two coils, the sensor has the property of inductance. When the two lines are used as two parallel electrodes, the sensor has the property of capacitance. When one spiral metallic line is used as heater and another one is used as resistor, the sensor has the property of temperature sensor.
The experiments show good results to discriminate each sample of materials and are expected as a step to develop an artificial skin tactile sensing system in future.