Development of a monolithic compliant SPCA-driven micro-gripper

This paper develops a monolithic compliant SPCA-driven micro-gripper for micro-assembly and describes the mechanism design, kinematic model, static model, control strategy and experimental verification of micro-gripper. The paper includes the following points: (1) the MCM integrates the lever mechanism and parallelogram mechanism so as to magnify the SPCA input and transform the linear input of SPCA into the clamping movement of gripping jaw. In addition, the kinematic model of the MCM is established to describe the relationship between the SPCA input and the output displacement of gripping jaw. (2) The static model of movement jaw is established to analyze the inherent relationship between the gripping force and the strain angle of flexible hinge. (3) The control strategy based on the incremental PID algorithm is applied to control the gripping manipulation of micro-gripper. The control strategy selects the visual or force feedback signal according to the contacting condition between the gripping jaw and clamped micro-object. Finally, a series of experiments were performed to validate the kinematic model, static model and control strategy of micro-gripper. In addition, a glassy micro-tube with 150 μm diameter was clamped non-destructively by the developed micro-gripper.