考虑关节摩擦的3-PRS并联机构动力学建模研究  

Dynamic Modeling with Joint Friction of 3-PRS Parallel Mechanism

作　　者：陈国强[1] 周红鹏 黄俊杰[1] 代军[1] 白秉欣 刘梦超 CHEN Guoqiang;ZHOU Hongpeng;HUANG Junjie;DAI Jun;BAI Bingxin;LIU Mengchao(School of Mechanical and Power Engineering, Henan Polytechnic University, Jiaozuo 454000, China)

机构地区：[1]河南理工大学机械与动力工程学院,焦作454000

出　　处：《农业机械学报》2021年第8期416-426,共11页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(U1304525);河南省科技攻关项目(212102210045、182102310706);河南省高校基本科研业务费专项(NSFRF200401)。

摘　　要：为了研究摩擦力对并联机构运动过程的影响,对3-PRS并联机构进行了基于关节摩擦力的动力学分析。对3-PRS并联机构进行末端理论运动轨迹规划,采用矢量法对机构进行了运动学分析。提出3种不同的关节摩擦模型,包括库伦摩擦模型、库伦粘性摩擦模型以及库伦粘性静摩擦模型,在考虑关节间摩擦的情况下,基于牛顿欧拉法建立了3-PRS并联机构的动力学分析模型。逆动力学实例分析表明,负载越大,摩擦力越大,在有无摩擦力的情况下,3个移动副驱动力的最大误差分别为1.40%、1.51%、1.49%。通过正动力学实例分析了不同情况下关节间摩擦模型对末端运动轨迹的影响,结果表明,不同关节摩擦模型对3-PRS并联机构末端的运动轨迹有较大的影响。In order to research the influence of friction on the operation of the parallel mechanism,the dynamic analysis of the 3-PRS parallel mechanism based on joint friction was carried out.Firstly,the ideal terminal motion trajectory of the 3-PRS parallel mechanism was planned,and the mechanism had three degrees of freedom(DOFs),including two rotation DOFs and one movement DOFs.The vector motion was used to analyze the kinematics of the mechanism,and the velocity and acceleration of each component were analyzed.Secondly,three joint friction models,including Coulomb friction model,Coulombviscous friction model and Coulombviscousstatic friction model were proposed.Under the condition of applying friction between joints,the dynamic modeling of the components and the overall structure of the 3-PRS parallel mechanism was established based on the NewtonEuler method.Finally,the influence of load on the friction of each joint was analyzed.The specified ideal motion trajectory was applied to the terminal of the mechanism.According to the inverse dynamics,the influence of joint friction on the slider driving force was analyzed and the maximum errors of the three slider driving forces were 1.40%,1.51%and 1.49%,respectively.The three slider driving forces from the inverse dynamics were taken as the main driving forces of the 3-PRS parallel mechanism,and the influence on the terminal motion trajectory caused by the different friction models between joints was analyzed through forward dynamics.The research results showed that the terminal motion trajectory of the 3-PRS parallel mechanism had great impact under different joint friction models.

关 键 词：3-PRS并联机构 动力学建模 牛顿欧拉法 摩擦模型 运动轨迹 

分 类 号：TH112[机械工程—机械设计及理论]