并联夹具机构灵巧性分析

针对汽车行业对制造系统以及包括夹具在内的所有部件的高模块化和灵活性的要求,提出一种具有高自配置性和灵活性的夹具系统。其中,安装在并联机构末端执行器上的夹具具有高刚度、高精度、可重构性,并且可以通过编程使其在工作空间中移动的特点。而并联机构作为自配置夹具系统的支持单元,在工作空间和动态特性方面具有一定的局限性。为了提高并联机构的综合工作性能,在工作空间中,分别以全局运动条件数和全局动态条件数作为运动灵巧性和动态灵巧性的评价标准。以工作空间体积、全局运动条件指标和全局动态条件指标为目标函数,对并联夹具机构进行优化,得到优化后的结构参数。

Dexterity Analysis of a Parallel Fixture Mechanism

A novel fixture system with advantages of high self-configuration and flexibility is proposed to meet the requirements of automotive industry to high modularity and good dexterity of manufacturing systems and all components including fixtures.All clamping elements attached to the end-effectors of parallel mechanisms have high stiffness,high accuracy,reconfigurability and programmability to move in their workspace.While the parallel mechanism,as a support unit of self-configurable fixture,has the limitations of workspace and dynamic property.In order to enhance comprehensive working performances,the global kinematics condition index and global dynamic condition index acted as an evaluation criteria of kinematics dexterity and dynamic dexterity were proposed respectively.Furthermore,the fixture mechanism was optimized by means of taking the volume of the workspace,the global kinematics condition index and the global dynamic condition index as objective functions.Finally,the optimized architecture parameters were obtained.