柔性二级差动式微位移放大机构优化设计

微位移放大机构常常用来扩大压电陶瓷致动器的行程范围。鉴于差动式微位移放大机构具有"小结构大倍数"的特点，设计了一种新型二级差动式杠杆微位移放大机构。应用矩阵表示法对其进行了运动静力学分析，在此基础之上，以柔性铰链的分布位置及其几何特征参数为优化变量，并以提高位移放大比和减小最大应力为目标函数建立一种双目标优化模型。机构经过优化设计后位移放大倍数高达48倍，并对其进行有限元仿真分析，计算结果为44倍，理论模型与有限元模型的误差小于10%。结果表明：提出的优化模型具有准确性和高效性，同样可适用于其他柔性铰链机构的优化设计。

Optimal Design of a Compliant Two-stage Differential Displacement Amplification Mechanism

Micro-displacement amplification mechanisms are frequently used to increase the stroke range of the piezoelectric actuator, and the differential micro-displacement amplification mechanism has the feature of large amplification ratio and small structure. Therefore, this paper presents a novel two-stage differential micro-displacement amplification mechanism. Kinetostatic analysis of the mechanism is carried out by using the matrix representation. A bi-objective optimization model is established aiming at improving the displacement amplification ratio and reducing the maximum stress. The mechanism is optimized to achieve a displacement magnification of up to 48 times, and the finite element simulation analysis is performed, its calculation result is 44 times, so the error between the theoretical model and the finite element model is less than 10%. The results show that the proposed optimization model is accurate and efficient, and can also be applied to the optimization design of other flexure-based compliant mechanisms.