Generation of partial medial axis for disassembly motion planning

Abstract: "This paper presents an efficient approach for determining disassembly motion plans of a subassembly in the free space within its parent subassembly. We propose a two-step approach to generating motion plans. First, all possible paths within free space of the parent subassembly are generated using a partial medial axis. This is followed by a graph search for an optimal global path. Second, a collision free motion is planned using the global path and the geometry of the moving subassembly. In this paper, we focus on the first problem, i.e.,generation of a partial medial axis for disassembly motion planning. We present a method to determine a partial medial axis (PMA) by generating Critical Points (CPs) and connecting them based on geometry of the parent subassembly.The PMA gives us all possible paths to disassemble subassembly out of its parent subassembly. The connectivity between segments of the PMAis represented in the form of a graph which is augmented with geometric information from the PMA. An optimal path is found by using graph search techniques on the augmented graph. A method called the two-disks motion planning strategy is proposed to plan the disassembly motion along the generated path. This method is discussed in detail in our companion paper [19]."