A siphon-based deadlock prevention policy for flexible manufacturing systems

This paper present a siphon-based algorithm of deadlock prevention for a type of Petri nets called S³PMR, a subclass of S³PGR². The proposed method is an iterative approach by adding two kinds of control places called ordinary control places and weighted control places to the original model to prevent siphons from being unmarked. An ordinary control place with ordinary arcs that optimally prevents the related siphon from becoming unmarked is employed whenever it is possible and otherwise weighted control places that adopt a conservative policy of controlling the release of parts into the system are used. Furthermore, this algorithm is not only for the subclass Petri nets but also for S³PR, ES³PR, S²LSPR and S³PGR² nets.