NEW CONCEPTS FOR HIGH-LEVEL PETRI NETS IN THE APPLICATION DOMAIN OF TRAIN CONTROL SYSTEMS.

Abstract High-level Petri nets have been used with great success as formal models for train control systems. Based on the experience of the European Train Control System in Braunschweig and our own in the case study of a railway crossing we have analysed the modeling capabilities of high-level Petri net techniques in this application domain. Although in general these techniques are well suited we have analysed difficulties concerning modularization, abstraction and openness. These concepts are highly important in the application domain, but not sufficiently supported by current techniques of high-level nets, like those provided by Design/CPN. In this paper we propose new ideas to overcome these problems. Corresponding new concepts for modularization, abstraction and openness are introduced and illustrated by small examples. We are confident that these new concepts can be formalized in an adequate way and wifi lead to improved modeling techniques for train control systems using high-level Petri nets.