宏微3-RPR并联机构建模及控制仿真研究

Modeling and Control Simulation Research of Macro-micro 3-RPR Parallel Mechanism

为解决并联机构大行程与高精度定位的矛盾,提出了一种采用电液伺服控制系统为宏驱动、压电精密控制系统为微驱动的宏微3-RPR并联机构,基于虚功原理推导了其动力学模型;搭建了其基于多软件协同仿真模型,其中包括Adams机械模块、AMESim液压与压电驱动模块、Matlab/Simulink控制模块;针对该并联机构是个复杂的多输入多输出非线性系统,采用模糊PID方法对其进行控制仿真研究。仿真表明:与常规PID相比,采用模糊PID能缩短响应时间,实现无超调的宏微切换过程;采用宏微驱动的并联机构能实现大行程的精密定位,具有良好的控制效果。

According to the contradiction between the large stroke and high precision of the parallel mechanism, a novel macro-micro 3-RPR parallel mechanism was presented which used the electrohydraulic servo control system as the macro driven and used the piezoelectric precision control system as the micro driven. Then, the macro-micro coupling dynamic model of the macro-micro 3-RPR parallel mechanism was deduced by principle of Virtual work. lts multi-software co-simulation model was built, including Adams mechanical module, AMESim hydraulic and piezoelectric diver module, Matlab/Simulink control module. According to the 3-RPR parallel mechanism characteristics of multi-input multi-output, nonlinear, strong coupling and so on, its control simulation research was conducted by using the fuzzy PID method. The simulation results show that compared with traditional PID, the single rod static and dynamic performance is improved by using the fuzzy control method and the macro-micro 3-RPR parallel mechanism can achieve high precision positioning of large stroke.