平面柔性并联机器人系统建模与仿真研究

Dynamics Modeling and Simulation for Planar Flexible-link Parallel Robots

利用运动弹性动力学理论和有限元方法研究了平面柔性并联机器人的动力学建模方法。分析了各运动支链的弹性位移及其耦合关系,提出了柔性并联机器人系统的运动学约束条件和动力学约束条件,综合考虑了构件的分布质量、集中质量、集中转动惯量以及杆件的各种弹性变形的影响,建立了平面柔性并联机器人的动力学模型。以平面3-RRR柔性并联机器人为例,用MATLAB语言编程进行了仿真计算,并用SAMCEF软件的计算结果验证了模型的准确性。仿真结果表明该动力学模型能正确地反映柔性并联机器人的弹性振动特性,杆件的弹性变形对机器人动平台的位置误差和方向误差具有重要影响。

Based on Kineto-Elastodynamics theory and finite element analysis method, the method of dynamics modeling for flexible planar parallel robots was investigated. The elastic deformations of flexible links and the coupling effects of the elastic deformations were analyzed. The kinematic constrain conditions and dynamic constrain conditions with respect to the elastic displacements of the planar flexible-links parallel robots were proposed. The dynamic model of flexible parallel robots was derived, including the effects of distributed mass of links, lumped mass and various kinds of elastic deformations of links. The dynamic behavior of the flexible planar parallel robots is welt illustrated through the numerical simulation of a planar 3-RRR parallel robot by using MATLAB program. Compared with the results of SAMCEF software simulation, the numerical simulation results show good coherence and the advantages of the method. The dynamic model can indicate the elastic vibration of flexible parallel robots. The flexibility of links is demonstrated to have significant impact on position errors and orientation error.