Fabrication and Characterization of 4-DOF Soft-Contact Tactile Sensor and Application to Robot Fingers

Abstract

This paper describes the development and application of a 4-DOF (degree of freedom) soft-contact tactile (SCT) sensor using 6-DOF micro force moment sensing (MFMS) chip. The 6-DOF MFMS chip is working based on the piezoresistive effect in single crystalline silicon and has been fabricated and calibrated completely. The MFMS chip has been packaged to produce a 4-DOF soft-contact tactile sensor, which has the contact part made of silicone rubber. The sensor can independently detect three components of force (Fx', Fy', Fz') and one components of moment (Mz'). The MFMS chip and the SCT sensor have been calibrated. The calibrated sensitivities to Fx, Fy, Fz, Mx, My and Mz components are SFx =0.06(mV/mN), SFy =0.054(mV/mN), SFz = 0.136 (mV/mN), SMx = 1.449 (mV/mum), SMy = 1.451(mV/N|im), and SMz = 0.751(mV/N|im), respectively, (bias voltage Vin = 2V). The sensitivities of the SCT sensor to the forces Fz', Fx' (or Fy') and moment Mz' are 0.085 (mV/mN), 0.039 (mV/mN) and 0.004 (mV/mum), respectively. The outputs were linear and the crosstalk was small. The sensor has been mounted onto robot fingers to sense the forces from gripping operation