扣件拆装机械手多体系统动力学研究

Dynamic study on multi-body system of fastener disassembly manipulator

高速铁路的大规模建设使无砟轨道精调作业业务量剧增,而针对轨道扣件的调整是无砟轨道精调作业中的关键一环,为解决目前人工精调愈发困难的问题,实现扣件拆装作业的自动化,针对精调作业现状设计了一种无砟轨道扣件拆装机械手。为全面地了解机械手在作业期间的动态特性,文中利用ADAMS软件建立了机械手主体结构的多刚体模型,根据实际运动情况设置了相应的约束和驱动,仿真结果表明该机械手虽然能够满足实际作业要求,但在运动过程中会出现加速度突变的情况。利用Ansys软件对机械手的主要受力构件进行柔性化处理,建立刚柔耦合动力学模型,结果表明机械手在运行过程中由于柔性体产生的弹性变形会导致机械手的运动轨迹产生较大的偏差。随后引入了S形速度曲线进行路径规划,机械手执行末端的最大偏移量由6.98 mm降至0.39 mm,机械手整机运行的平稳性得到提升。

In the large-scale construction of high-speed railway,the application of fine adjustment of ballastless track has increased dramatically.Considering that the adjustment of track fasteners is the key part of fine adjustment of ballastless track,in order to solve the difficulty of manual fine adjustment at present,and to realize the automation of fastener disassembly and assembly,a design of fastener disassembly manipulator for ballastless track is proposed according to the present situation of fine adjustment.In order to fully understand the dynamic characteristics of the manipulator during operation,the multi-rigid-body model of the main structure of the manipulator was established by using ADAMS software,and the corresponding constraints and drives were set according to the actual movement situation.The simulation results show that although the manipulator can meet the actual operation requirements,there will be sudden acceleration changes in the movement process.Through Ansys software,the main mechanical components of the manipulator were treated flexibly,and the rigid-flexible coupling dynamic model was established.The results show that the elastic deformation of the flexible body will lead to a large deviation in the manipulator’s trajectory during running.After introducing the S-shaped speed curve for path planning,the maximum offset of the manipulator’s execution end was reduced from 6.98 mm to 0.39 mm,and stability of the manipulator in running was improved.