A Contribution to the Validation to of Operating Mode Switching: Application to Satellite
Résumé
We propose a methodology for modeling systems with different operating modes using Nested Petri Nets (NPNs) based on Valk's approach, where each token can be also considered as one Petri Net. NPNs provide a powerful tool for concurrent modeling and introduce interesting properties such as synchronization at a hierarchical level. In order to manage operating modes of critical and complex systems these properties are used to define and link component behaviors to the global system, through synchronized transitions. In order to formally verify these properties, CTL formulae will be used, translated from a logical table of technical specifications. The formulae allow a formal validation of the model and an examination of its coherency when the system switches to a new operating mode, under the influence of exceptional events. This verification is possible namely by using logic programming tools for the simulation and model checking. It is illustrated through a case study concerning a satellite's control unit