On the scenario and heuristics of disassemblies

A general scenario of disassembly is figured out, starting from the authors´ past study of the internal structures of machines and devices, based on a mechanical engineer´s point of view. The authors argue that among all data relevant to assembly, the key data for generating assembly sequences are the liaison type and the assembly direction. From these data many important geometrical, topological and technological constraints can be inferred that can be used as criteria for reducing the user´s input data and the information to be extracted from the CAD database. These criteria minimize the possible decompositions at each stage of disassembly, and may even guide the search towards the best plan. A fast planner has been implemented in PROLOG, giving a user friendly system capable of generating optimal assembly plans very quickly, with a computational cost roughly proportional to the number of parts in the final assembly