并联柔性铰机器人的静刚度研究

Study on the static stiffness of the parallel flexure joint robot

并联柔性铰机器人是一类具有超精密定位能力的微动操作手，对这类采用非常规运动副的微动机器人，其静刚度在相当程度上决定了机器人的有载定位精度。该文首先通过一系列坐标系的建立和转换，导出终端位姿的摄动位移与柔性铰微变形间的映射关系，进而利用虚功原理提出并联柔性铰机器人的静刚度模型，显示出影响静刚度的主要因素不仅与传动刚度有关还与柔性铰的刚度有关，此外通过该模型研究了静刚度特性，其结果可用于指导机构优化设计。最后，以实例分析了并联柔性铰机器人的静刚度。

The parallel flexure joint robot is a micromanipulator with ultraprecise positioning ability. As using the unnormal pairs, its positioning accuracy under load mainly depends on static stiffness. Therefore, it is very important for the designer to be able to predict the stiff property of such micromanipulator. In this paper, the mapping between the end effector's purturbative displacement of position and attitude and the micro deformation of the flexure joints was derived through the transformations of a series of coordinate systems; The static stiffness model was established by the principle of virtual work; The static stiffness properties of the parallel flexible joint robot was discussed. An example was given and the results show the model reveals that both transmission stiffness and the flexible joint stiffness influence the static stiffness and can be used to guide the optimal design of the structure.