摘要
目的为并联机床找到最优的工作空间范围,提出一种含闭环球铰的三自由度并联机构。方法根据并联机构的运动学反解,首先求解速度雅克比矩阵;随后在速度雅克比矩阵的基础上,分析并联机构的3种奇异位置,给出奇异位置的数值解,并仿真并联机构在剔除奇异位置情况下的理论可达工作空间;最后,分析并联机构的灵巧度,找到并联机构在理论可达工作空间下灵巧度为0的位置,确定并联机构动平台实际可达工作空间。结果在剔除奇异位置和灵巧度为0的位置之后,并联机构实际可达空间的x轴位移从[-10 mm,5 mm]减小到[-9 mm,-5.4 mm],z轴位移从[-790 mm,-650 mm]减小到[-790 mm,-677 mm],并联机构的转角范围由理论范围的[-30°,80°]转变为[32.544°,64.114]。结论通过分析灵巧度的方式得到并联机构的实际可达工作空间,证明灵巧度对并联机构的工作空间有着较大的影响,从而为该并联机构用于并联机床设计提供一定的理论依据。
The work aims to propose a three-degree-of-freedom parallel mechanism with closed global hinges to find the optimal workspace of parallel mechanism.Based on the reverse solution of the parallel mechanism,the velocity Jacobian matrix was first solved.Then based on the velocity Jacobian matrix,three singular positions of the parallel mechanism were analyzed,and numerical solutions of the singular positions were given.The theoretical reachable workspace of the parallel mechanism after elimination of singularities was simulated.Finally,the dexterity of the parallel mechanism was analyzed to find the position where the dexterity of the parallel mechanism was 0 under the theoretical reachable workspace,and the actual reachable workspace of the moving platform of the parallel mechanism was determined.After singular positions and 0 dexterity positions were eliminated,the x-axis displacement of the actual reachable space of the parallel mechanism was reduced from[-10 mm,5 mm]to[-9 mm,-5.4 mm],and the z-axis displacement was reduced from[-790 mm,-650 mm]to[-790 mm,-677 mm],and the rotation angle range of the parallel mechanism was changed from[-30°,80°]of the theoretical range to[32.544°,64.114°].The actual reachable workspace of the parallel mechanism is obtained by analyzing the dexterity.It proves that the dexterity has a great influence on the workspace of the parallel mechanism,and thus it provides a certain theoretical basis for applying the parallel mechanism in the design of parallel machine tools.
作者
李虹
王新宇
胡洋
马春生
李瑞琴
LI Hong;WANG Xin-yu;HU Yang;MA Chun-sheng;LI Rui-qin(School of Mechanical Engineering,North University of China,Taiyuan 030051,China)
出处
《包装工程》
CAS
北大核心
2020年第21期202-207,共6页
Packaging Engineering
基金
山西省自然科学基金(201801D121183)。
关键词
并联机构
奇异位置
理论可达工作空间
灵巧度
实际可达工作空间
parallel mechanism
singular positions
theoretical reachable workspace
dexterity
actual reachable workspace
