动力学特性是并联机构的一项重要性能。该文以一种用于航天复合材料加工的混联机器人中的2UPU/SP并联机构为研究对象，考虑两个UPU运动学支链的平面约束特性，建立了该3自由度并联机构的运动学模型，并基于虚功原理，推导了动力学模型。给出一种动力学性能评价指标，该指标以一个驱动力为单位量且其他驱动力小于或等于单位量时的动平台最大加速度来评价并联机构的加速性能。基于给出的动力学性能评价指标，对2UPU/SP并联机构的线加速度和角加速度分别进行评价，并与一种传统的2UPS/UP并联机构进行比较，结果表明2UPU/SP机构具有更好的加速度性能。
The dynamics characteristic of parallel mechanisms are very important. This study analyzed the dynamics of a 2UPU/SP parallel mechanism in a hybrid robot for aerospace composite machining. A kinematics model was developed using the virtual work principle for the three-degree-of-freedom parallel mechanism including the plane constraints of the two UPU kinematic branches. The maximum acceleration of the moving platform when one driving force is a unit force and the other driving forces are less than or equal to the unit force was used to evaluate the parallel mechanism. This performance index was used to separately evaluate the effects of linear acceleration and angular acceleration of the 2UPU/SP parallel mechanism compared with a traditional 2UPS/UP parallel mechanism. The results show that the present 2UPU/SP mechanism has better acceleration characteristics.
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