Did you know that we also use ‘hybrid’ technology in ERTMS?

We have a name for it 👀 and it is ‘Hybrid Train Detection’ (HTD)🚦

In our ERTMS bubble, Hybrid Train Detection is an integrated cab-signalling and ‘Automatic Train Protection’ (ATP) system combining train positioning, length (Train Integrity Monitoring system, (TIMS)) and limited ‘trackside train detection’(TTD).

How does it work 👀?

A Radio Block Centre (RBC) always knows where a train starts but doesn’t always know where the 🍑 of the vehicle is (or its exact length). The TIMS helps the RBC recognise the exact length of the train, including where its 🍑is located.

Let’s dive in🚝

HTD systems can operate with both fixed and moving virtual blocks. These virtual subsections are a software implementation configured in the trackside system that divides the physical detection blocks into smaller block sections. The section borders are physically marked by trackside Stop Marker Boards (SMB). If a train follows another train that is not equipped with onboard TIMS, safe operations are ensured by the trackside train detection.

As illustrated in our visual, the trains equipped with TIMS notify other vehicles of their length, allowing those behind to advance to the virtual section. However, when one of the trains lacks TIMS and operates solely on TTD, it cannot communicate its precise length. Consequently, the train behind it cannot proceed to the virtual section ahead, as the RBC is unaware of the second train’s 🍑.  Finally, our little third 🚝cannot access the physical track segment depicted in the image with marker boards.

Why use HTD?

There are several key drivers for replacing legacy systems which can be identified as follows:

🔸the renewal of existing signalling systems,

🔸the need for increased railway capacity,

🔸enhancements to system safety functionality, and the commitment to European policies for interoperable signalling.

💡Did you know that:

Level 2 HTD is fully compliant with the ETCS Baseline 4 specifications. It facilitates a seamless transition from solely TTD-based implementations to HTD and from Class B systems directly to HTD.

And what about freight trains❓

Currently, there are no freight trains equipped with TIMS in Europe. Therefore, the development of the DAC system plays a crucial role in Level 2 HTD.

#ERTMS #HTD #TTD #TIMS #RailTransport #Innovation #Sustainability #FutureRail