A Magnetostrictive Tactile Sensing Unit and the Integration of Sensor Array for Intelligent Manipulator

A magnetostrictive tactile sensing unit and the integrated sensor array have been developed, based on the sensing process of human skin and the inverse magnetostrictive effect. The working mechanism of the magnetostrictive tactile sensing unit has theoretically been studied by using electromagnetism theory and cantilever beam theory, and the relationship between the applied force and output voltage has been determined. The measurement of sensing performance about the static and dynamic force has been carried out, and it is found that the sensitivity of a sensing unit is 127 mV/N, resolution is 0.07 N, and response time is 24 ms. The sensing unit possesses a high reliability with the test of 5 000 cycles. The optimum distance between adjacent sensing units of the sensor array is determined by COMSOL multiphysics software when the sensing unit is integrated into a sensor array. By integrating four magnetostrictive tactile sensing units into a 2 $\times 2$ sensor array, it could monitor and map the force distribution applied on the manipulator in the grip. The tactile sensor array shows great potential within the application of intelligent manipulator.