Abstract
A new method of implementing process planning under a competitive environment is proposed for a single-stage multifunctional production system, such as a machining center. This system, named the "Dynamic Process Planning System", has a strategic decision function in order to overcome competitive factories. The main characteristic of the system with the strategic decision function is the ability to quickly change the process plan by analyzing the competitive data. In order to competitively machine workpieces as a product on a pallet under the minimum elapsed time criterion, the completion time of workpiece machining in one's own factory must be within that of the machining time of the competitor factory. To realize this idea, a hierarchical model consisting of four sub-systems with a strategic decision was developed under the minimum elapsed time criterion. This system implements the appropriate process planning, while adjusting the solutions of the following four sub-problems as needed by the decision maker : (Prob. 1) workpiece grouping and machining conditions, (Prob. 2) allocation of workpieces, (Prob. 3) sequence of machining operations, and (Prob. 4) pallet scheduling. These problems are connected with a hierarchical structure. Finally, actual use of the proposed dynamic process planning system is demonstrated as an example.
