摘要
三维圆柱铰的动态性能对空间机构的运动精度和动力学特性有着重要的影响。基于多体动力学方法和刚体有限元方法,提出考虑三维圆柱铰的间隙碰撞和动态接触作用的空间机构柔性多体接触动力学方法。采用圆柱-圆柱的线接触力学模型和切片法,计算圆柱-圆柱的接触变形量和接触力,建立三维圆柱铰的轴销与轴套之间的间隙碰撞作用和三维动态接触关系。以等效刚体单元和Timoshenko梁单元描述柔性杆件的刚性有限元模型,建立柔性连杆和三维圆柱铰的具有多刚体系统的统一形式的动力学方程。计算分析了含三维圆柱铰的空间机构的运动精度和动力学特性,获得空间机构的位移响应,三维圆柱铰的相对运动轨迹和动态作用力等动力学响应。采用三维圆柱-圆柱动态线接触方法,能有效地预测空间机构系统的三维圆柱铰持续接触、间隙碰撞状态和摩擦作用下的动力学特性。计算结果表明三维圆柱铰的间隙碰撞作用对空间机构的运动精度和动态特性的影响较为显著。动力学模型和计算结果对复杂工况下高精度多间隙的空间机构的动态设计和动力学研究具有重要的理论意义。
Dynamic characteristics of 3-D cylindrical hinge have important influences on kinematic accuracy and dynamic characteristics of spatial mechanisms.Here,based on multibody dynamic method and rigid finite element one,a flexible multibody dynamic analysis method for spatial mechanisms considering 3-D cylindrical hinge clearance collision and dynamic contact was proposed.The contact deformation and contact force of cylinder-cylinder were calculated by using the cylinder-cylinder line contact mechanical model and slicing method to establish the clearance collision action and 3-D dynamic contact relationship between shaft pin and shaft sleeve of 3-D cylindrical hinge.The rigid finite element model of flexible bar was described with equivalent rigid body element and Timoshenko beam element to establish dynamic equations of flexible link and 3-D cylindrical hinge with the unified form of multi-rigid body systems.The kinematic accuracy and dynamic characteristics of a spatial mechanism with 3-D cylindrical hinge were calculated and analyzed.The spatial mechanism’s displacement response,3-D cylinder hinge’s relative motion trajectory and dynamic force were obtained.The dynamic line contact method of 3-D cylinder-cylinder was used to effectively predict dynamic characteristics of spatial mechanism’s 3-D cylindrical hinge under action of continuous contact,clearance collision and friction.The calculating results showed that the clearance impact of 3-D cylindrical hinge has significant effects on kinematic accuracy and dynamic characteristics of spatial mechanism;dynamic model and calculation results have important theoretical significance for dynamic design and dynamic research of high precision multi-clearance spatial mechanisms under complex working conditions.
作者
姚廷强
陈锐搏
王立华
刘孝保
YAO Tingqiang;CHEN Ruibo;WANG Lihua;LIU Xiaobao(School of Mechanical and Electric Engineering,Kunming University of Science and Technology,Kunming 650093,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2021年第1期297-307,316,共12页
Journal of Vibration and Shock
基金
国家自然科学基金项目(11462008)。
关键词
三维圆柱铰
空间机构
刚性有限元方法
多体动力学
间隙
3-D cylindrical hinge
spatial mechanism
rigid finite element method
multibody dynamics
clearance
