Flexible process sequencing using Petri net theory

This paper presents a new methodology for flexible process sequencing using a Petri net based approach. In the proposed approach Petri nets are used as a unified framework for representing both operation planning knowledge and process sequence. In specific, the approach taken comprises: (1) modeling operation selection and sequencing knowledge using a Petri net based approach, (2) representing the flexible sequence of operations using Petri net formalism, and (3) linearizing a flexible process sequence using T-INVARIANT analysis. An illustrative example of HoleMakingProcess has been used to demonstrate the Petri net modeling, the operation selection and sequencing procedure (called state propagation procedure), and the linearization procedure.