A tactile sensor based on piezoresistive effect and electromagnetic induction

Abstract

To measure tri-axis force and detect slippage, a tactile sensor based on a thin film with a piezoresistive array and a particular structure with an induction-coil array and a permanent magnet was originally presented. The sensor is made up of a thin film containing piezoresistive cells for tri-axis force measurement, a two-dimensional array of induction coils and an elastomer with a permanent magnet inserted for slippage detection. As a result, the signals utilized to assess tri-axis force and identify slippage are independent. The proposed tactile sensor is prototyped, and experiments with a six-axis force/torque sensor as a reference sensor are carried out. In tri-axis force detection, experimental results reveal that the developed tactile sensor has a high accuracy and little tactile crosstalk. The sensor could also detect slippage information using the induction coils' output voltages directly and fast, according to the results. As a result, the proposed tactile sensor might be used in applications that need tri-axis force measurement and slip detection, such as robotic grasping and manipulation. Furthermore, the proposed tactile sensor in itself could be overall flexible as a flexible tactile sensor, even as a flexible array, which is easy to be integrated into different robotic applications like artificial skins.