Design and Analysis of a Compliant Micro-gripper with LBL Type Displacement Amplifier

This paper presents the design and analysis of a compliant piezo-driven micro-gripper with large tip displacement supporting micro scale manipulations. An integrated lever-bridge-lever (LBL) type amplification mechanism is proposed to achieve a large tip displacement, which incorporates the merits of lever-type and bridge-type mechanism. An analytical model of the proposed micro-gripper is established to predict the output displacement based on elastic beam theory, which is also capable of estimating the gripping force. Numerical simulations based on Finite element analysis (FEA) are conducted to validate the performance of the proposed micro-gripper and the effectiveness of the modeling method. The results demonstrate that the proposed micro-gripper has a large gripping range for grasping micro-objects with different sizes and its characteristics is accurately predicted by the model, which has the tip displacement of 280 μm corresponding to the input stroke of 16 μm for a single jaw.