Computer-aided alternative process planning in a dynamically changing manufacturing environment

Existing Computer-Aided Process Planning (CAPP) systems are limited in their utility because they ignore manufacturing system dynamics. This research presents a generic architecture and conceptual formalism for an Alternative Process Planning (APP) system which is able to continuously monitor the execution status of the system and adaptively control the generation of alternative process plans in a dynamically changing manufacturing environment. The APP formalism contains a set of temporal logic expressions and a multipartite network representation schema to formally describe the control and reasoning processes of alternative process planning. A continuous, non-zero-one temporal availability index is developed to evaluate the qualification of alternative manufacturing resources. A two-step problem abstraction procedure is constructed to provide the procedural foundation for solving the APP problem more efficiently. CAPP-II, a second generation of the CAPP system which implements the design concept of the APP formalism, is also developed to create a closed-loop control system for generating alternative process plans.