对一种空间3自由度3-UPU对称并联机构进行动力学分析和联合仿真研究。该并联机构由两个完全相同的平台通过3个同样的UPU支链连接而成，其动、定平台始终关于一个中间平面对称，该机构具有两个转动自由度和一个移动自由度。利用矢量法推导机构各构件的速度与加速度，求解机构各分支的雅可比矩阵，运用虚功原理建立3-UPU并联机构的动力学模型。利用联合仿真技术对该并联机构动力学模型进行验证，通过两个运动算例验证了该动力学建模方法的可行性和有效性，特别是利用该动力学模型分析这个机构在发生定轴转动时的动力学特点，为该机构的进一步研究及实际应用奠定了基础。
The dynamic analysis and co-simulation research of a 3-UPU symmetrical parallel mechanism are studied. This mechanism is comprised of two identical platforms and three UPU branches. The base and moving platform are always symmetrical about a middle plane, and it has two rotational and one translational (2R1T) degrees of freedom (DOFs). Firstly, the velocity and acceleration of all the links are derived, the Jacobian matrices of the legs are solved, and the dynamic model of the mechanism is established by virtual work principle. Then, the dynamic model is verified by the co-simulation method. Two numerical examples are given to demonstrate the feasibility and effectiveness of this dynamic model. Especially, the dynamic characteristic of this mechanism during the fixed-axis rotation is analyzed, which is useful for the further study and practical application.
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