CONNECTA-2 · Project

Wireless Train Control Systems That Cut Cabling Costs and Enable Flexible Rail Operations

transportTestedTRL 5

projects.shift2rail.org

Imagine every train today is wired like a Christmas tree from the 1990s — thousands of copper cables connecting brakes, doors, and controls. CONNECTA-2 built wireless replacements for those cables, so trains can talk to their own parts over the air, brake without physical wires, and even couple with other trains automatically — like Bluetooth for railway systems. They built two working lab demonstrators (one for regional trains, one for urban metro) and aimed to prove it all works at near-real-world conditions. Think of it as upgrading trains from landline phones to smartphones.

By the numbers

Laboratory demonstrators built (regional and urban segments)

TRL5

Target technology readiness level for most developments

SIL4

Safety integrity level for communication networks

Consortium partners

80%

Industry partners in consortium

Countries involved (DE, ES, FR)

Total project deliverables

The business problem

What needed solving

Train manufacturers and operators are stuck with massive wiring harnesses — thousands of copper cables per vehicle — that are expensive to install, heavy, hard to maintain, and make it nearly impossible to flexibly couple and decouple train units on the fly. Every new train design requires months of cabling work, and any modification to formations requires physical reconfiguration. This drives up both manufacturing costs and operational inflexibility.

The solution

What was built

The project built 2 laboratory demonstrators (regional and urban train segments) featuring wireless train backbone networks, wireless consist networks, SIL4-rated brake-by-wire systems, Functional Open Coupling for dynamic train joining, and a virtual certification simulation with hardware-in-the-loop testing. A physical demonstrator was also prepared for InnoTrans 2020. Across 12 deliverables, the consortium validated these technologies toward TRL5.

Audience

Who needs this

Railway signalling and onboard electronics suppliers (e.g., companies supplying TCMS subsystems)Regional rail operators wanting to reduce vehicle maintenance and cabling costsRailway certification and testing bodies evaluating wireless safety-critical systemsTrain manufacturers designing next-generation rolling stock (e.g., CAF, Alstom, Siemens Mobility competitors)Metro and urban transit operators looking to run flexible train formations

Business applications

Who can put this to work

Railway rolling stock manufacturing

enterprise

Target: Train manufacturers and system integrators

If you are a train manufacturer spending months on wiring harnesses for each new vehicle — this project developed a wireless Train Control and Management System with 2 laboratory demonstrators (regional and urban) that replaces physical train backbone cables with wireless networks. With 10 industrial partners validating the approach across 3 countries, this could cut your vehicle integration time and cabling material costs significantly.

Urban public transit operations

enterprise

Target: Metro and light rail operators

If you are a transit operator struggling with rigid train formations that cannot adapt to peak vs. off-peak demand — this project built Functional Open Coupling technology demonstrated at lab level, enabling trains to dynamically join and split formations wirelessly. The system targets SIL4 safety certification, the highest level required for braking systems, meaning it meets the same safety bar as your current hardwired setup.

Railway signalling and safety systems

enterprise

Target: Rail signalling and onboard systems suppliers

If you are a signalling supplier looking to offer next-generation onboard systems — this project developed drive-by-data and brake-by-wire capabilities with SIL4-rated communication networks, plus a virtual certification simulation that could accelerate your approval process. The consortium of 8 industry players built this on two different software approaches (modified AUTOSAR and custom OS), giving you integration options for your existing platform.

Frequently asked

Quick answers

What would it cost to adopt this wireless TCMS technology?

The project data does not include specific licensing costs or per-unit pricing. As a Shift2Rail joint undertaking output, the IP arrangements follow Shift2Rail consortium rules. Contact the coordinator (CAF, Spain) through SciTransfer to discuss commercial terms and technology access.

Can this scale to full production trains, not just lab demos?

The project targeted TRL5 (technology validated in relevant environment) for most developments, with 2 laboratory demonstrators built for regional and urban train segments. An InnoTrans 2020 demonstrator was also planned. Moving from TRL5 to production-ready (TRL7-9) would require additional on-vehicle testing and certification campaigns.

Who owns the intellectual property and can I license it?

IP is governed by the Shift2Rail Joint Undertaking rules and the consortium agreement among 10 partners across 3 countries. The coordinator CAF (a major Spanish rolling stock manufacturer) would be the primary contact for licensing discussions. SciTransfer can facilitate an introduction.

Does this meet railway safety regulations?

The project specifically targeted SIL4 communication networks — the highest Safety Integrity Level under railway standards (EN 50129). The brake-by-wire system was designed to support drive-by-data concepts under this safety regime. Full certification would still require type approval by a Notified Body for specific vehicle applications.

How long until this could be deployed on real trains?

The project closed in July 2021 at TRL5. Typically, moving from TRL5 to commercial deployment in rail takes 3-5 years of engineering, homologation, and pilot testing. Some consortium members (like CAF) are active train manufacturers who may already be advancing elements toward product integration.

How does this integrate with existing train systems?

The project built the Functional Distribution Framework using two different approaches — modified AUTOSAR (an automotive standard adapted for rail) and a custom implementation on a specific operating system. This dual-path approach was designed to offer integration flexibility with different existing onboard architectures. Hardware-in-the-loop simulation was also developed for integration testing.

Consortium

Who built it

This is a heavily industry-driven consortium: 8 out of 10 partners are private companies, with zero universities — unusual for an EU project and a strong signal that this is aimed at near-market application, not academic publishing. The coordinator CAF is one of Europe's major train manufacturers (headquartered in Spain), and the 3-country spread across Germany, Spain, and France covers the continent's biggest rail markets. The single research organization likely handled safety validation or simulation. With 80% industry ratio and major OEMs involved, the technology has strong commercial champions already positioned to carry it forward.

Construcciones y Auxiliar de Ferrocarriles, S.A.Coordinator · ES
DB SYSTEMTECHNIK GMBHthirdparty · DE
DEUTSCHE BAHN AGparticipant · DE
SOCIETE NATIONALE SNCFparticipant · FR
CENTRO DE ENSAYOS Y ANALISIS CETEST SLthirdparty · ES
CAF POWER & AUTOMATION SLthirdparty · ES
SIEMENS MOBILITY GMBHparticipant · DE
ALSTOM TRANSPORTATION GERMANY GMBHparticipant · DE
ALSTOM TRANSPORT SAparticipant · FR
CONSTRUCCIONES Y AUXILIAR DE FERROCARRILES INVESTIGACION Y DESARROLLO SLthirdparty · ES

How to reach the team

CAF (Construcciones y Auxiliar de Ferrocarriles) in Spain — a publicly traded rolling stock manufacturer. SciTransfer can facilitate a direct introduction to the project team.

Order a report on this consortium See Construcciones y Auxiliar de Ferrocarriles, S.A. profile →

Next steps

Talk to the team behind this work.

Want to explore wireless TCMS technology for your fleet or product line? SciTransfer can connect you with the CONNECTA-2 consortium and provide a detailed technology brief tailored to your specific railway application.

Order a report on this topic More in Transport & Mobility