Calculating restart states using reset transitions

This paper presents a supervisory control theory based offline approach for calculating restart states in a manufacturing control system. Given these precalculated restart states, an operator can be given instructions for how to correctly resynchronize the control system and the manufacturing resources during the online restart phase, as part of the error recovery process. Restarting from a restart state guarantees that all requirements on the nominal and the restarted productions are fulfilled. The paper includes an empirical comparison showing that the proposed approach enables restart states calculation for systems of sizes that could not be handled using an earlier presented approach.