A contact position detection and interaction force monitoring sensor for micro-assembly applications

This paper presents a piezoresistive sensor for micro-assembly application, which is capable of detecting the contact position of the micro-object on the grasping surface as well as the grasping force. By comparing the outputs of a local 2D force sensor and a global force sensor, the 2D contact position on the grasping surface and the contact force can be extracted. The device is fabricated with an IC-compatible process and can be integrated into micro-grippers. The measurement results show that different contact positions can be distinguished. The device is suitable to detect a contact force up to 4 mN, with a sensitivity of 16.4 V/N. The estimated force resolution is 1 muN.