A decision logic schema of process planning using backward chaining reasoning

Decision logic of process planning is one of the most difficult issues in the research on computer-aided process planning (CAPP), and also a bottleneck hampering the process of pragmatization and commercialization of CAPP. A proper methodology for decision logic of process planning is essential for describing or specifying the various decisions associated with combinations of conditions in process planning. This paper presents a decision logic schema of process planning using backward chaining reasoning in mathematical logic to address process reasoning formalization in automated process planning, which is based on a meta-modeling paradigm of the manufacturing resources [19]. The meta-modeling paradigm combines mapping theory with the first- & second-order logic in mathematical logic to address modeling the manufacturing resources and to provide a methodology for the extraction of specific process knowledge. The meta-modeling paradigm lays the foundation for the proposed decision logic schema with specific process knowledge while the decision logic schema is the extension and application of the results from the meta-modeling paradigm. The decision logic schema provides a systematic methodology for the decision-making process and inference mechanism in process planning from the global viewpoint, which can be applied to eliminate the variability from the planners’ judgement and experience. Finally, an application example is used to illustrate the decision logic schema.