一种新型3-RPC柔性精密平台设计与分析

基于3-RPC并联机构提出一种由压电陶瓷驱动的新型3-RPC柔性精密平台模型，并在初始构型的基础上对移动副、圆柱副、连接运动副的连杆等进行结构的优化设计，然后采用有限元法对相同尺寸的初始构型和优化后构型进行静力学分析；采用齐次变换法，建立该机构位置正反解表达式，得到柔性精密平台压电陶瓷驱动的柔性移动副输入与上平台微位移输出之间的关系，并进行有限元软件的加载试验，验证正、反解结果；根据设计原理，得出该精密平台的原理误差，计算出功能方向与非功能方向的位移误差，同时对比输出位移和误差大小，用有限元法验证理论分析结果的正确性。研究结果表明柔性精密平台具有运动解耦，结构紧凑，控制方便的特点，具有较好的应用前景。

Design and Analysis of Novel 3-RPC Flexible Precision Platform

Based on 3-RPC parallel mechanism, a novel model of flexible precision platform is proposed, which is driven by piezoelectric ceramic actuator. And moving pair, cylinder, connecting rod motion pair of structure are optimized based on the initial configuration. Then using the FEA simulations, static analysis of the same size of the initial configuration and the optimization is analysed. Using Homogeneous transformation method, the forward and inverse kinematics of 3-RPC is gained. Obtained the relationship of flexible precision platform driving by piezoelectric ceramic actuator between the input of move pair and the micro displacement output of the upper platform, and loading test by finite element software, testing the solution results of the forward and inverse kinematics. Based on design principle, the error of principle of the precision platform is analyzed and calculated the displacement error on function and non-function direction, while comparing the output displacement and the size of the error. And the correctness of the analysis results is validated by FEA simulations. The results of the study show that the flexible precision platform has several advantages in the aspects of kinematics decouple, structure simple, control easily and a good application prospect.