CONNECTED DRIVER ADVISORY SYSTEM

Connected Driver Advisory System (C-DAS) allows calculated information to be continuously sent to train drivers. The important difference to Standalone Driver Advisory System (S-DAS) is the connectivity aspect and having a real time data link between train and trackside, so schedule updates on disruption are automatically sent to the C-DAS for use on-board. With S-DAS, the system stops operating when the train is running significantly off-timetable due to disruption. Another example would be platform changes, the signalling system may have to route a train into a different platform than planned due to another train running late. C-DAS can keep up to date with the new route as well as any changes in line speed and speed profile due to the different route.

Some may think C-DAS takes responsibility away from a driver, but this is not the case and (as the name suggests) C-DAS only ‘advises’ a driver. A competent driver is still required to control the safety critical aspects of the train. Several successful C-DAS applications have been created and used on several railways across the world. Generally, for new C-DAS, it is necessary to add new on-board processing and communication equipment, as well as driver machine interfaces to convey information to the drivers. However, with the cab-mobile version of C-DAS, the mobile radio’s connectivity is used to exchange data with the ground system using 4G.

The minimum requirement is to upgrade the existing GSM-R antenna with the SMBA that supports 4G LTE and GNSS/GPS as well as GSM-R. This would use the existing fourline GSM-R display, but a graphical display to provide additional information in addition to just train speed is available. This is easy to install as it reuses the existing location of the standalone S-DAS display via an adapter bracket. Trials of the system have demonstrated fuel savings of typically up to 15%, which is a very strong business case for activation of the app.

The main benefit of C-DAS over standalone or networked DAS is the connectivity to the C-DAS trackside server to ensure the driving advice is automatically based on the latest operational plan. One challenge is that there is no common railway location referencing scheme in Britain used by all the sources of data C-DAS requires, so the trackside software must map between them, for example:

» Temporary Speed Restrictions (TSRs) and quarter mile post locations (to display the current location to the driver), which use Line of Route (LoR) and Engineers Line Reference (ELR).

» Schedules and schedule updates, which use Timing Point Locations (TIPLOCs) that are areas such as junctions and stations, as well as line in and path out codes.

» Data on static speed, gradient and signal locations (for train describer berths) from scheme plans, which use meters from a datum.

» Track centrelines, which are GNSS Latitude and Longitude polylines to allow the C-DAS on-board to map it’s GNSS location of the train to the schedules, TSRs, and the static speed profile and gradient profile of the track ahead.

The national passenger information system, Darwin, provides schedule updates that C-DAS can use in areas without a suitable deployment of Traffic Management (TM). Darwin adjusts the schedule timings for late running detected by the train describer stepping feed, and shares any platform changes from the baseline timetable entered by operators. TM plan/ re-plan systems aim to optimise the overall current plan of train movements to an agreed Key Performance Indicator (KPI), allowing plan changes to be tested first in a sandbox environment and the evaluation of knock-on impacts between trains, before commitment.

Where TM is deployed, it is important that C-DAS makes use of the TM published schedule updates, via the Network Rail Layered Information Exchange (LINX) system. In some scenarios, this would provide earlier awareness of any plan changes, which C-DAS could use to advise a reduction in speed further in advance than with a later Darwin update, potentially saving even more energy. This also ensures the C-DAS driving advice is based on a current plan, consistent with what is being fed to the Automatic Route Setting (ARS) systems controlling the signalling route setting.

Cab Radio Management Terminal

Another system functionality app that has proved useful is the Cab Radio Remote Management Terminal (CRMT), which allows the management of cab radios remotely via an IP connection. Using the radio’s in-built connectivity, a whole fleet’s set of cab radios can be monitored, with everything from versions and serial numbers through to error logs being accessible remotely. Software can also be updated remotely, along with phone book entries and message templates. The implementation of CRMT removes the need for a technical visit to the train, improving efficiency and reducing the cost and risk that every train visit entails.

Future App Capabilities

With the cab radio now effectively becoming a mobile communications gateway, many other apps can be provided for other systems on the train using the SMBA 4G LTE capability and Ethernet network interface.

Currently under development are solutions that allow remote public address announcements to be made to trains or groups of trains for enhanced passenger information. Timely accurate passenger information can help to keep passengers who face delays informed so they can plan ahead. Having a journey disrupted annoys passengers, but knowing why their journey has been disrupted, what is being done to resolve things, and what their options are, can all help to maintain their confidence in rail.

The cab secure radio system which preceded GSM-R also had a train public address link, but it only allowed the signaller’s radio dispatcher to make train public address announcements. The problem was that signallers are not trained, or do not have the time, to make public address announcements, and it was only used in emergency situations.

With the GSM-R cab radio app, a secure IP connection can easily be provided to any train operator’s GSM-R dispatcher or automatic public address system.

Future Communications Potential

Whilst the original 2G GSM-R has performed well for many years, the need for a new communication technology is driven by the obsolescence of GSM-R, and the move to 5G-based communications is essential to provide the voice and data communications which the railway will need from 2030 onwards. The replacement of GSM-R with Future Railway Mobile Communication System (FRMCS) is still some years away and will take some time to implement, so each of the app ideas are important for deployment now.

From 2030, however, the implementation of enhanced radio solutions with FRMCS will offer the potential for an even greater step change in train and trackside service integration. Siemens says its GSM-R cab radio platform is capable of being upgraded to use FRMCS, so any investment in the cab radio should not be wasted and FRMCS will see faster, more secure, and more reliable communications which can be exploited in future applications.

The train-borne apps of today will be superseded by solutions that can benefit from more bandwidth, for example video systems to monitor passenger spaces, and allow higher grades of automation. Far more data from the complex ‘system of systems’ that will make up new rolling stock will need to be transmitted back to control centres, so that data can be integrated with information from a multitude of trackside systems to provide a system-wide integrated view of the railway. The railway of the future will see connectivity and data as critical to a smooth, efficient, and reliable network, which is the obvious choice for travellers. This can only happen if rail can be made affordable and make the best use of the assets it already has.

A Crucial Step

Futureproofing technology is critical if the industry is to keep up with the rapid change of system technologies, especially in areas like communications; but it is possible to mitigate the impact of both obsolescence and technology change. A lot of time, effort, and money has been involved with fitting GSM-R equipment to trains. The experience of providing additional functionality to the on-board cab radio has demonstrated that it is possible to build on this investment, to add additional capability in an inexpensive and nonintrusive way, and be a step to FMRCS.