薄壁四点接触球轴承-腕部关节系统接触动力学分析  

Thin-walled four-point contact ball bearing-wrist joint system contact dynamics analysis

作　　者：赵宝旭 姚廷强[1] 钱建伟 赵德春 ZHAO Baoxu;YAO Tingqiang;QIAN Jianwei;ZHAO Dechun(School of Mechanical and Electrical Engineering,Kunming University of Science and Technology,Kunming 650500,China)

机构地区：[1]昆明理工大学机电工程学院,云南昆明650500

出　　处：《机电工程》2024年第5期870-877,共8页Journal of Mechanical & Electrical Engineering

基　　金：国家自然科学基金资助项目(12162016)。

摘　　要：在机器人实际工况中,针对含有薄壁四点接触球轴承的机器人腕部关节系统的运动稳定性问题,对腕部系统模型进行了简化设计和仿真研究。在考虑薄壁结构的弹性变形和动态接触作用耦合影响的基础上,建立了刚柔耦合工业机器人腕部关节系统模型,分析了不同受载工况和正反转驱动下的变形规律和动态特性。首先,基于多体动力学和Hertz接触理论,设计了包含薄壁四点接触球轴承和中空轴及基座的腕部关节系统刚柔耦合接触动力学仿真模型;然后,考虑薄壁中空轴、基座、轴承套圈和保持架的结构弹性变形、钢球和套圈滚道、保持架的动态接触作用,研究了机器人腕部关节系统两种实际工况对保持架和钢球角速度、保持架和薄壁基座振动位移、钢球与套圈的动态接触力的影响;最后,计算分析了两种工况下腕部关节系统的动态载荷规律和振动响应特性。研究结果表明:在相对较大的径向载荷作用下,保持架和钢球会出现打滑现象,速度呈现周期波动,保持架和基座具有更好的运动稳定性,其薄壁轴承内部载荷降低,主副接触对均承担联合载荷,轴承内部载荷稳定性也更好。该仿真模型及结果可以为薄壁腕部关节系统的动力学分析与设计提供参考。Aiming at the problem of motion stability of the wrist joint system with thin-walled four-point contact ball bearings in the actual working conditions of the robot,the simplified design and simulation of the wrist system model were studied.Considering the coupling effect of elastic deformation and dynamic contact of thin-walled structure,a rigid-flexible coupling wrist joint system model of industrial robot was established,and the deformation law and dynamic characteristics under different loading conditions and positive and negative driving were analyzed.Firstly,based on multibody dynamics and Hertz contact theory,a simulation model of rigid-flexible coupling contact dynamics of wrist joint system including thin-walled four-point contact ball bearing,hollow shaft and base was designed.Then,considering the structural elastic deformation of the thin-walled hollow shaft,the base,the bearing ring and the cage,the dynamic contact effect of the steel ball and the ring raceway and the cage,the effects of the two practical working conditions of the robot wrist joint system on the angular velocity of the cage and the steel ball,the vibration displacement of the cage and the thin-walled base,and the dynamic contact force between the steel ball and the ring were studied.Finally,the dynamic load law and vibration response characteristics of the wrist joint system under the two working conditions were calculated and analyzed.The results show that under the action of relatively large radial load,the cage and the steel ball will slip,the speed will fluctuate periodically,the cage and the base have better motion stability,the internal load of the thin-walled bearing is reduced,the main and auxiliary contact pairs bear the combined load,and the internal load stability of the bearing is also better.The simulation model and results can provide a reference for the dynamic analysis and design of thin-walled wrist joint system.

关 键 词：刚柔耦合工业机器人 腕部关节系统模型 薄壁四点接触球轴承 结构弹性变形 振动特性 动态接触 薄壁中空轴-球轴承-基座的刚柔耦合多体接触动力学模型 

分 类 号：TH133.3[机械工程—机械制造及自动化] TP242.2[自动化与计算机技术—检测技术与自动化装置] TH113[自动化与计算机技术—控制科学与工程]