TRAXX P160 DE, Locomotive, Czech Republic

Driverless automated transit systems

CITYFLO 550 is a system for driverless (DTO) or unattended (UTO) train operations designed for airport people movers (APM) and automatic operation for mass transit systems. CITYFLO550 is one of the most proven and widely used microprocessor-based interlocking systems introduced into the market. The system is used for automatic running of trains on segregated tracks.

The system has the following main characteristics:

  • Non-communication-based train control (CBTC) APM fixed block system
  • Driving supported by automatic train protection (ATP) (UTO level)
  • ATP information through audio frequency track circuits
  • Automatic train operation (ATO) functionality with continuous driving strategy modification
  • Segregated track
  • Train detection by track circuits
  • Continuous train supervision through EBI Screen control room
  • EBI Lock integrated interlocking function
  • Point machines controlled by interlockings
  • Optional SCADA functionality can be added to the EBI Screen control room
  • The EBI Screen control room can connect to auxiliary systems
  • The CITYFLO 550 solution allows for integration of auxiliary systems such as:
    • Passenger information displays (PIDs)
    • CCTV
    • Public announcement (PA)
    • Radio
    • Telecoms

EBI Screen control room

The vehicle is supervised by the EBI Screen control room system. This is a modern computer-based control and supervision system allowing the operator to give commands through a mouse or keyboard with the facility to have the position of the vehicles and optional wayside objects shown on both normal display screens and large rear projection screens. The EBIScreen control room also provides train regulation for the system.

EBI Lock computer-based interlocking

The CITYFLO 550 solution can use the built-in interlocking function. The CITYFLO 550 built-in interlocking function is located with the regional wayside ATP.

EBI Com radio block centre

The CITYFLO 550 solution's wayside equipment is divided into geographical regions. Each region has duplicated ATP and ATO equipment that handles the ATP and ATO functions for the trains in that region. Each region controls a number of track circuits that receive the train positions and then send out movement authorities to the trains.

EBI Link ATC wayside equipment

The information needed from the track for the precision stopping in ATO mode is passed to the train through a program stop tape located at each station. These tapes give the exact distance to the stopping point of the train and allows the train to adjust its braking to stop in the correct place.

EBI Switch point machines

A standard railway point machine from the EBI Switch point machine range can be used if the system is running on steel wheels. If the system has rubber wheels, the point machine is not supplied by Bombardier Transportation.

EBI Cab onboard equipment

The onboard equipment consists of the EBI Cab vehicle automatic train protection (VATP) and vehicle automatic train operation (VATO) which is an onboard system allowing a modern ATP system with continuous supervision and continuous update of this information. The 'fixed block' ATP system has an American safety certification for public transport and a German TÜV Rheinland approval.

The CITYFLO 550 solution has an ATO system that allows fully automatic DTO/UTO with continuous change of driving strategies which can be selected automatically through the EBIScreen control room at any time during the journey. The ATO system allows precision stopping by the train at stations with a typical accuracy of +/- 15 cm.

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