A new compliant microgripper with integrated position and force sensing

This paper presents the design and development of a new compliant microgripper with integrated position and force sensing capabilities. The gripper mechanism is devised and verified by performing finite element analysis (FEA), and it is fabricated using the wire-electrical discharge machining (EDM) process. The gripper is driven with a piezoelectric stack actuator (PSA) and the position and force feedback are realized via two groups of strain gauges, which provide the (2σ) resolution of 0.22 μm and 1.02 mN, respectively. With the calibrated sensors, the static and dynamic performances of the gripper are characterized. Moreover, a position and force switching control scheme is implemented to demonstrate the effectiveness of the microgripper system for grasp-hold-release operation of a copper wire of 300-μm diameter. The developed microgripper system is capable of conducting microassembly of micro objects along with both position and grasping force regulated.