柔性铰链微位移放大机构在精密机械中的应用日益广泛。依据卡氏第二定理,采用基于柔度的静力学分析方法对柔性机构的运动特性进行分析,给出了机构中任意节点处位移的计算式。在此基础上,对柔性对称微位移放大机构进行了分析,建立了微位移放大机构输入、输出位移及其放大比求解的数学模型。利用所建立的模型,采用MATLAB编程对柔性对称微位移放大机构进行了理论计算,同时对其进行有限元分析,两种方法所得结果基本一致,输入位移、输出位移的相对误差在3%左右,并对误差产生的原因进行了分析。
The micro-displacement amplification mechanisms with flexure hinges are increasingly used in precise mechanism.The input displacement,output displacement and amplification ratio are key performance parameters,which are very important for analyzing and designing the mechanism.Based on The Castigliano's second theorem,the static analytical method based on the compliance is used for analyzing the compliant mechanism,and then the displacement equations of a certain node in the compliant mechanism are formulated.Using the derived equations,the paper analyzes the compliant symmetrical micro-displacement amplification mechanism,thus the mathematical models of the input displacement,output displacement and amplification ratio are established.Based on the established mathematical model,theoretical calculations by means of MATLAB programming are implemented for the compliant symmetrical micro-displacement amplification mechanism,and the finite element simulation are performed simultaneously.Good agreements between theoretical calculations and simulation results are observed with errors of about 3% in input displacement and output displacement.Finally,the reasons causing the error are analyzed.