Simulation of the ASFA system in an ERTMS simulator

Due to the economic, technical and functional advantages that the simulation tools of different railway signalling systems present and the possibility of driver training, an ASFA system simulator (Automatic Signalling and Brake Warning System) has been developed. This simulator includes on-board and on-track equipment. This system has been integrated in an ERTMS simulator allowing the generation of mixed scenarios as they happen on the new ERTMS lines that also use the ASFA safety system. By integrating the ASFA system into another simulator both simulators are able to share several elements such as the virtual cab, applications for generating scenarios... but on the other hand, it has been necessary to develop new elements that simulate ASFA specifications. These elements have been implemented in C++ and Component and Variables Register technologies have been used. The former allows us to divide the problems into less complicated modules that are assignable to real elements such as balises, signals, buttons... and the latter allows us to manage an exchange of variables among the different components that make up the system. The ASFA components, which it has been necessary to generate since they are very different from those used in ERTMS, are the following. ASFA balises are devices that send information from the infrastructure to the train using the same messages defined in ASFA specifications; the antenna or sensor of the train has to receive the message from the balises and this message is transmitted to the processor unless some failure is simulated; the processor of the on-board equipment oversees the protection logic that the ASFA system develops; and the relay panel is the man-machine interface that shows the driver information relative to the state of the signals and the train, and which, in addition, allows the driver to realize certain actions and acknowledgements of the system.