并联机构动力学建模及控制研究

Survey on dynamic modeling and control of parallel manipulators

为了系统地研究并联机构动力学特性,分析了4种基本建模方法(牛顿-欧拉方法、直接拉格朗日方法、拉格朗日-达朗贝尔方法和虚功原理方法),总结了各种方法的优缺点。在此基础上,对动力学的3种控制算法(经典PD控制、机器人控制中常用的计算力矩控制以及数控加工中的先进轮廓控制)在并联机构上的应用进行了分析研究。针对开发的三自由度(3-DoF)纯平动并联机构Orthopod,采用拉格朗日-达朗贝尔方法进行了动力学建模,并对其进行了控制仿真。研究结果显示,轮廓控制在轮廓误差控制方面具有更好的性能,适合于雕刻机的控制应用。

In order to study the dynamic features of parallel manipulators, four methods, such as Newton-Euler formulation, direct Lagrange formulation,Lagrange-D＇ Alembert formulation and the virtual work, were analyzed. Advantages and shortcomings of those four formulations were concluded by a comparison. Three control strategies, such as PD control, computed torque control and contouring control, were researched for controlling of parallel manipulators. For demonstration purpose, the Orthopod of the 3-DoF purely translational parallel manipulator, was modeled in Lagrange-D＇ Alembert formulation. Three control strategies were implemented in simulation. Research result shows that the contouring control has better performance in contouring accuracy, and it is suit for controlling the engraving machine.