P/sup 3/: a process planner for manufacturability analysis

In complex practical domains, such as manufacturing, plans generated must not only be feasible, they must also be of high quality (i.e., efficient, reliable, etc.). The particular quality criterion used is determined according to the objectives and needs of the planner. This paper describes P/sup 3/, an automated process planner for generating manufacturing plans for prismatic machining processes. P/sup 3/ is constraint-based, and it utilizes the LCOS (least commitment to operator selection strategy) to facilitate the construction of efficient, high quality plans. The ability to develop high quality plans depends on the ability to make trade-offs at a global level among factors that are frequently conflicting. LCOS is a search strategy that facilitates these objectives by making the appropriate information available so as to allow globally efficient plans to be constructed. P/sup 3/ implements the LCOS strategy in an algorithm called MACHINE, which combines LCOS with a variety of search pruning strategies to construct globally efficient plans while avoiding rapid combinatorial explosion. Lastly, P/sup 3/'s operation is illustrated through the construction of an illustrated example manufacturing plan, and its performance will be evaluated. The result is a planner which is more scalable to problems containing large numbers of goals, while still maintaining high solution quality. It is hoped that the general strategies presented can provide useful and scalable frameworks for modeling planning problems in other complex practical domains.