Deadlock prevention policy for a class of petri nets based on complementary places and elementary siphons

摘要

For a class of Petri nets called Systems of Simple Sequential Processes with Resources , this paper proposes a sufficient condition under which there exists a complementary-place supervisor to enforce their liveness. Moreover, an algorithm is proposed to design liveness-enforcing supervisors based on complementary places and elementary siphons. The significance of the proposed policy lies in its design simplicity. A flexible manufacturing system example shows that in some cases, the proposed policy can obtain a structurally simpler supervisor with 99.9 % maximal permissive behavior.