Geometric abstractions to support disassembly analysis

Determining whether an assembly can be constructed from its components at the design stage potentially reduces downstream assembly problems. This determination can be accomplished by performing a disassembly analysis of the assembly's geometric model. This paper presents two abstractions derived from the assembly's geometric model that can determine the validity of the assembly: (1) the Assembly Topology Graph (ATG); and (2) the set of boundary components. The first abstraction, the ATG, is a graph whose nodes represent the components in the assembly and whose edges represent a non-null intersection of the convex hulls of component pairs. The second abstraction, the set of boundary components, represents components that intersect the boundary (or convex hull) of the assembly. These boundary components are typically the ones most accessible with respect to disassembly. This paper also discusses an algorithm, which utilizes the ATG to determine pair-wise interlocking components. If such component pairs are absent, then the disassembly sequence for the removal of components in the assembly is determined by analyzing the set of boundary components for disassembly. This procedure is repeated until all the components in the assembly are disassembled (for a valid assembly).