In: International Journal of Production Research, Vol. 38, No. 18, pages 4671-4682. 2000.
Abstract: In Petri nets (PNs), because all the input places of a transition are connected to each other with logical AND to enable the transition, logical OR connections among its input places cannot be modeled. In the case of k alternatives (logical ORs) to perform a task, e.g., assembly of a product, k transitions are required to model these k alternatives in a PN model, each transition representing one alternative. This increases the number of transitions in a PN model when the number of alternatives increases. This paper introduces CARPN to model the same k alternatives with fewer transitions and places. The similarities between PN and CARPN are discussed, and based on these similarities formal analysis methods are introduced, as well as a new type of graphical representation. Because the elements of the incidence matrix of a CARPN are integers, the current techniques to obtain the invariants of PN can also be applied to CARPN. In the case of systems having similar structures, the reduction of the incidence matrix is also discussed.
Keywords: AND/OR Petri nets, assembly systems, high-level Petri nets.