Extended Simple Colored Petri Nets

We present a new class of Petri Nets, called Extended Simple Colored Petri Nets (ESCP-nets), which are essentially Simple Colored Petri Nets (SCP-nets) with three added features: first, there is a built-in type of real numbers; second, tokens can be forced to wait in places; third, an interface specifies how the Net can be externally supervised. Even if these added features also add complexity, ESCP-nets still constitute a valuable trade-off between the simplicity of P-nets and the convenience of CP-nets. We have successfully employed ESCP-nets in an industrial project for Demag-Italimpianti (the largest Italian industry producing plants), consisting in the realization of software tools for the development and execution of plants built according to an architecture where an ESCP-net executor is supervised by means of declarative rules about the marking of the Net. Even if we have presently employed ESCP-nets in the field of plant simulation only, their characteristic might be well-suited to other fields as well.