Petri Nets and Java. Real-Time Control of a flexible manufacturing cell

In this paper, we propose a control architecture and development environment based on Petri nets (PN) and the Java programming language. The architecture covers the coordination and local control layers of flexible manufacturing systems and is composed of several threads that interact through monitors. The proposed structure can be analyzed to guarantee control deadlines in the system. To support the real time and concurrent characteristics, we used the Java real-time specification. In addition, we propose the specification of control using PN that allow automatic code generation, which we present as a new PN technique called concurrent coordinators where classical centralized and decentralized concepts are merged. To demonstrate the practical utility of technique, we have applied it to the control of a flexible manufacturing cell.