中文摘要：

研究了一种三自由度并联模块的刚度建模方法.该模块采用冗余驱动技术,可满足搅拌摩擦焊作业高刚度、大工作空间/机座体积比要求.分析了该模块的结构组成与工作原理,并应用螺旋理论建立其刚度解析模型,所获广义雅可比矩阵与驱动/约束刚度矩阵物理含义清晰.借助有限元分析验证刚度解析模型的有效性,进而实现全域刚度性能预估,为该模块的刚度优化设计及物理样机开发提供了理论依据.

英文摘要：

Stiffness modeling method of a 3-degree-of-freedom（3-DOF）parallel module was studied. The redundant joint of the module could meet the requirements of the friction-stir welding for high stiffness and large ratio of workspace to base. The topology structure and working mechanism of the module were analyzed and the stiffness model of the parallel module was established based on screw theory,whose Jacobian matrices of actuations and constraints were of clear physical implication. Effectiveness of the stiffness model was validated using finite element method and stiffness evaluation of the whole workspace was achieved,which provides theoretical foundation for optimal stiffness design and physical prototype development of the redundantly actuated parallel module.