HETEROGENEOUS PETRI-NET METHODOLOGY FOR THE DESIGN OF COMPLEX CONTROLLERS

A controller design methodology based on Petri nets is developed. The semantics of the method, and the algorithm for the construction of an equivalent finite state machine make use of both synchronous and asynchronous marking graphs giving rise to the name 'heterogeneous Petri nets'. The method allows the designer of a controller greater freedom in the use of well structured graphics specifying the controller while the supporting CAD tool ensures an efficient (in the sense of clock-cycle usage) derivation of an equivalent finite state machine.