An Efficient and High-Accuracy Modeling and Design Method for High-Load, Large-Stroke Piezo-Actuated Compliant Amplification Mechanisms

Piezoelectric-actuated nanopositioning stages commonly employ flexure amplification mechanisms to enlarge output displacement and are widely used in optical measurement, micro and nano manufacturing, and other precision engineering fields. However, existing methods still have limitations in computational efficiency, hinge modeling accuracy, and displacement prediction under external loading. To address these limitations, this paper proposes a generalized compliant-chain modeling method in which flexure hinges are treated as compliant units connected by rigid elements, improving computational efficiency relative to repeated finite element modeling. A multi-configuration hinge model (MCH model) is established to analyze the effects of hinge configurations and mechanism parameters on key performance indices, thereby improving prediction accuracy and extending the design space. A load-induced displacement loss model (LDL model) is further developed to characterize output displacement loss under external loading and improve the applicability of the method to loaded conditions and integrated systems involving multiple flexure mechanisms. Finite element simulations and experiments are conducted to validate the proposed models. The results show that the prediction errors of the amplification ratio and stiffness are both within 5%, while the designed mechanism achieves a high amplification ratio of 17.55. These results indicate that the proposed method provides competitive prediction accuracy and displacement amplification performance among similar flexure amplification mechanisms. The proposed method provides an effective modeling and design tool for amplification mechanisms requiring large stroke and high load capacity.