Abstract Mechanisms with multiple operation and multiple locomotion modes are applied to implementing the different tasks and adapting to the changes in terrains as well. Based on this application, this paper presents a refined virtual chain approach which is applied to the type synthesis of a class of multi-mode mobile parallel mechanisms (PMs). This approach is based on screw theory to synthesize the branches with coaxial rotating components under different constraint conditions. The geometric orientations of the different constraint conditions in a plane can be changed by using coaxial rotating components. Meanwhile, the inactive joints in branches are determined. By means of this approach, a number of symmetrical and asymmetrical reconfigurable PMs with four branches are obtained. The four of the multi-mode PMs are sketched as examples and the operation and locomotion modes for the mechanisms are discussed.

中文翻译：

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基于细化虚拟链法的多模移动并联机构类型综合

摘要 采用多操作、多运动模式的机制来执行不同的任务，并适应地形的变化。基于此应用，本文提出了一种改进的虚拟链方法，该方法应用于一类多模式移动并行机制（PM）的类型综合。该方法基于螺旋理论，在不同约束条件下合成具有同轴旋转分量的分支。通过使用同轴旋转组件，可以改变平面中不同约束条件的几何方向。同时，确定分支中的非活动关节。通过这种方法，获得了许多具有四个分支的对称和非对称可重构PM。