论文标题
使用基于图的路径计划器的平行五杆操纵器的输出模式切换
Output Mode Switching for Parallel Five-bar Manipulators Using a Graph-based Path Planner
论文作者
论文摘要
并行操纵器的配置歧管比串行操纵器表现出更多的非线性。从定性上讲,它们可以看到额外的褶皱。通过将这种歧管投影到工程相关性的空间上,例如输出工作区或输入执行器空间,这些折叠式的边缘呈现出表现非滑动行为的边缘。例如,在五键链接的全局工作区域内部内部出现了几个本地工作空间边界,这些边界仅限制了机制的某些输出模式。当专门研究这些投影而不是配置歧管本身时,这种边界的存在(在输入和输出投影都表现出来)都是混乱的根源。尤其是,非对称平行操纵器的设计已被其输入和输出空间中的外来投影所困扰。在本文中,我们用半径图表示配置空间,然后通过使用同型延续来量化传输质量来解决每个边缘的重量。然后,我们使用图形路径计划器来近似于避免传输质量低区域的配置点之间的大地测量学。我们的方法会自动生成能够在非邻近输出模式之间过渡的路径,该运动涉及示波多个工作空间边界(本地,全局或两者)。我们将技术应用于两个非对称五杆示例,这些示例表明如何通过切换输出模式来选择工作空间的传输属性和其他特征。
The configuration manifolds of parallel manipulators exhibit more nonlinearity than serial manipulators. Qualitatively, they can be seen to possess extra folds. By projecting such manifolds onto spaces of engineering relevance, such as an output workspace or an input actuator space, these folds cast edges that exhibit nonsmooth behavior. For example, inside the global workspace bounds of a five-bar linkage appear several local workspace bounds that only constrain certain output modes of the mechanism. The presence of such boundaries, which manifest in both input and output projections, serve as a source of confusion when these projections are studied exclusively instead of the configuration manifold itself. Particularly, the design of nonsymmetric parallel manipulators has been confounded by the presence of exotic projections in their input and output spaces. In this paper, we represent the configuration space with a radius graph, then weight each edge by solving an optimization problem using homotopy continuation to quantify transmission quality. We then employ a graph path planner to approximate geodesics between configuration points that avoid regions of low transmission quality. Our methodology automatically generates paths capable of transitioning between non-neighboring output modes, a motion which involves osculating multiple workspace boundaries (local, global, or both). We apply our technique to two nonsymmetric five-bar examples that demonstrate how transmission properties and other characteristics of the workspace can be selected by switching output modes.