AN OPERATIONS NETWORK GENERATOR FOR COMPUTER-AIDED PROCESS PLANNING

Computer aided process planning (CAPP) forms the critical bridge between computer aided design (CAD) and computer aided manufacturing (CAM). Generating consistent and flexible process plans to suit a dynamic production environment is an important objective. Geometric tolerancing and dimensioning when properly applied ensures the most economical and effective production of part features. This can provide a functional production technique by which the engineering drawing specifications are translated into production instructions by means of a process plan. Most of the process planning systems currently available do not generate alternate process plans. Process planning is a decision making task whose decisions should take into account the production control objectives. Any fixed sequence of operations that is generated by a process plan is not necessarily the best possible sequence since the production environment changes as do the criteria for optimality (such as quality, quantity, machine utilization, etc). The aim then should be to generate all the possible feasible operation sequences. The decision maker can then use the necessary optimality criteria to get the best sequence for the prevailing operating environment. A methodology is presented in this paper for the generation of alternate feasible operation sequences using a tree structure approach.