An interoperable ATO system, compatible with ETCS, and covering all Grades of Automation

The purpose of this activity is to contribute to the development of the European ERTMS/ATO specifications. The intention is to have ETCS as the Automatic Train Protection (ATP) system, which supervises the train movement from a safety point of view. The ATO on-board system is able to drive the train automatically, based on timetable information from the trackside. It will attempt to meet the timetable and, where possible, do this in an energy efficient way.

The ATO system is defined by the following Grades of Automation (GoA):

• GoA1 – manual driving, with possible support for the driver by a Driver Advisory System (DAS), provided by the ATO on-board system
• GoA2 – automatic driving with driver still present in the cab, able to take back control of the train when needed
• GoA3 – automatic driving without driver, but other staff present in the train, ready to support in degraded situations
• GoA4 – automatic driving without any need for staff in the train

The ATO on-board system has a direct interface with the ETCS on-board system to ensure ATO is only operatable when it is allowed by ETCS. The ATO on-board system also has an interface with the physical train to allow control of the traction and brake. In addition, the ATO on-board system has a continuous communication with the ATO trackside system. In GoA1 and GoA2, where the driver is still in the cab, the relevant ATO information will be shown on the ETCS DMI. In GoA3 and GoA4, where there is no driver present to supervise the track, the ATO on-board system will also depend on the existence of an on-board perception system.

The ATO specifications were first developed in Shift2Rail, where EUG participated. This development was split into two workstreams, progressively covering the different GoAs. The first workstream, with the focus on ATO GoA2 (including DAS for GoA1), officially ended by end of March 2022 with the delivery of a set of stable specifications for the ATO system. The specifications were delivered to the EECT process and have been released in the 2023 CCS TSI release. The second workstream, with the focus on ATO up to GoA4 (e.g. also covering the compatibility with the existing GoA2 specifications), finished by end of December 2023 with the delivery of a set of stable specifications for the ATO system up to GoA4. These specifications were delivered to the EU-Rail for further development with the final goal to be included in a coming CCS TSI release.

In parallel, further work is already ongoing in EU-Rail regarding ATO, with several projects both in the Innovation Pillar and System Pillar, and although EUG is not directly involved in the Innovation Pillar, EUG still supervise the development via the involvement in the System Pillar.

In EUG, the ATO topics are currently managed inside the TSG.