A Multistage Amplification Compliant Adjustable Constant-Force Gripper Using M-Shaped Beams

Abstract Compliant constant-force grippers are key devices for manipulating micro-sized objects without damage in micro-operation/assembly systems. This article introduces a multistage amplification compliant adjustable constant-force gripper utilizing M-shaped beams and inclined beams. A multistage amplification mechanism is devised to achieve a high amplification ratio and a sufficient stroke, while a preloading mechanism driven by a micrometer is designed for constant-force adjustment. The constant-force mechanism and the amplification mechanisms are modeled by the large deflection analysis based on the elliptic integral method and the compliance matrix method. In addition, a series of simulations and experiments are carried out to demonstrate the working performance of the gripper. The experimental results show that the gripper exhibits an amplification ratio of 66.66, a stroke of 1.79 mm, a constant-force output of 0.112–2.452 N, and a maximum constant-force displacement of 0.841 mm. It shows appropriate results in terms of the discrepancies between the theory and experiments.