Hybrid synthesis for hierarchical structured Petri nets

A hierarchically structured Petri net synthesis method, including both top-down and bottom-up constructions, is proposed. The method allows multiple inputs and outputs in which: if at some instance of time exactly one input is Activated, then the system will consume the input and will produce exactly one output after some finite length of time. The top-down approach provides a stepwise refinement which enforces the input-output constraints for each. subsystem in the refinement. The bottom-up approach provides sequential, parallel, and loop constructions, while again enforcing the input-output constraints during the construction, The paper concludes with a small manufacturing example.