Process planning for a modular component placement system

This paper discusses the design of a hierarchically structured process planning system for a printed circuit board assembly line. Basically, the assembly system consists of a series of independently operating placement modules, connected by a carrierless conveyor system. Both the modules and the conveyor system are fully automated, while the complete system is also under centralized computer control. The authors show how the process planning problem is naturally decomposed into a series of hierarchically coupled subproblems, each of a combinatorial nature. Models for all subproblems are developed and solution techniques are briefly indicated. Numerical results for a number of industrial cases are also discussed.