Design and implementation scheme for an alternate process planning system—A-CAPPS

Abstract This paper presents the design and development of a computer-aided process planning system (CAPP) that generates least-cost alternate plans. The developed system takes production capacity, machine capability, and operation cost into account to determine feasible process plans for a product mix. Traditional CAPP systems generate one process plan per part. Their use in most production systems has been found to be limited due to frequent non-availability of machines and other resources recommended by the CAPP system. In addition, advanced manufacturing systems such as an FMS normally offer alternate feasible routes for part production. Hence, CAPP systems should be able to generate cost-efficient alternate process plans that can be adopted to circumvent such problems. The proposed methodology integrates order processing, aggregate planning, resource grouping, loading, process cost estimation, process planning, and finally scheduling. It considers loading of part families to each cell in the FMS. Each cell is generally known as a flexible manufacturing cell (FMC). The total workload of a part is divided into batches, based on the demand for a planning period. Different batches of a part mix required in the planning period will determine the part production schedule (PPS). The development of a prototype system based on a variant approach is discussed. The system a-capps is capable of generating alternate process plans to satisfy various capacity constraints. The plan combination for a product mix generated by a-capps is then evaluated for system performance using a simulation model. A case example is discussed to demonstrate the applicability of the developed system.