Magnetostrictive Tactile Sensor Array for Robotic Grasping

Abstract

Tactile sensors play a significant role in robotic grasping. This study compares the output characteristics of magnetostrictive sensor array and TakkTile sensor array which is a commercial product. Magnetostrictive sensor unit is composed of Galfenol wires, permanent magnets, Hall elements, bottom fixture and contact pad. Multiple magnetostrictive tactile sensors are integrated on the flexible printed circuit board to form a 3 × 3 magnetostrictive sensor array. The sensitivity of magnetostrictive sensor array is 48.47 mV/N, which is up to 380% higher than minimum value of the commercial sensor array. The recovery time is only 10 ms, 86.7% faster. Quantity available on ReFlex finger is twice the latter. By comparing the results of grasping experiments with the two types of sensor array, magnetostrictive sensor array exhibits simpler structure, smaller temperature drift and more accurate force measurement. Experimental results show that magnetostrictive sensor array can improve the result of robotic grasping.KeywordsMagnetostrictionSensorRobotic grasping