【作者】 牛国栋；

【导师】 郭宗和；

【作者基本信息】 山东理工大学 ， 机械设计及理论， 2006， 硕士

【摘要】 精度是并联机器人机构最重要的性能指标之一,它直接影响机器人的工作质量。本文在对三平移并联机器人机构进行运动学和工作空间分析研究的基础上,对其精度分析和精度补偿进行了较系统的研究。首先,对三平移并联机器人机构进行了拓扑结构分析,通过矢量方法推导出了其位置正、反解的解析解。将三平移并联机构的三个分支拆成三个单开链,分别对每一个单开链进行分析,求出了并联机器人机构工作空间的解析解,为机器人机构的精度研究提供了极大方便。其次,全面分析了三平移并联机器人机构结构参数和位姿参数对其输出位姿精度的影响。根据三平移并联机器人机构位置解矢量方程,利用机器人全微分理论建立了机器人精度分析的数学模型,通过计算机仿真研究了机器人的结构误差、结构尺寸变化和位姿变化等对机器人精度的影响,为该机器人的实际精度补偿与控制提供了理论论据。最后,根据三平移并联机器人机构具有三个可控的移动自由度的特点,应用并联机器人精度分析的正解模型,从理论上推导出一种三平移并联机器人机构位姿精度补偿的方法。该方法实现了通过对机器人机构驱动杆补偿量的控制,来提高并联机器人输出位姿精度的目的。最后结合典型实例仿真,证实了该方法的有效性。更多还原

【Abstract】 Accuracy is one of the most important working performances of parallel robotmechanism, which affect the working accuracy of the parallel robot directly. Thisdissertation deals systematically with the error analysis and accuracy compensation of3-DOF parallel translational manipulators, based on the study of kinematics and workspaceof it.Topological structure of 3-DOF parallel translational mechanism is analyzed, and theclosed-formed analytic solutions for both the forward and inverse kinematics aredeveloped by using vector method. The closed-formed analytic solutions of parallelmechanism’ workspace is obtained, which offered maximum facilities for the further studyof parallel mechanism.According to the inverse solutions of 3-DOF translational parallel robot mechanisms,in which both the base and the mobile platform are triangle and similar to each other, theaccurate model of parallel robot mechanisms is established by the differentiation of thekinematics. The effects of length error of driving poles, structure size change and posturechange on the accuracy of robot are studied by simulations, which provided a foundationfor practical error compensation and control of the mechanism.A method of accuracy compensation of 3-DOF translational parallel robotmechanisms is proposed theoretically by using the forward error model of translationalparallel mechanisms, for the 3-DOF translational parallel robot mechanisms have threetranslational freedoms. The purpose of improving the output position and pose accuracy ofparallel mechanisms is realized, with controlling telescopic link of parallel mechanisms. Atlast the method is proved effective by example simulation.更多还原