In-Depth Look: Driverless Technology and the Main Subsystems

In-Depth Look: Driverless Technology and the Main Subsystems

Italian engineering future runs along the tracks

The main subsystems on which the driverless system is based are: ATC, Automatic Platform Doors, Vehicle, Electric Power Supply, Telecommunications, SCADA, Access Control and Tariff, Civil Systems.

ATC (Automatic Train Control)

The ATC system manages the processes through which the movements of the vehicles are controlled and regulated in safety and efficiency, allowing the trains to operate automatically without on-board driving personnel, both along the line and in the depot areas.

The automatic train driving system consists of three subsystems that have been tested separately in many railway infrastructures and metros for a long time:

  •       ATP (Automatic Train Protection) is an automatic protection system that controls the distance and speed between trains. Used since the beginning of the last century in the first metros, it ensures the safe operation of the transport system, for example, by imposing a safe distance between trains, respecting the speed limit in the various sections, and safely boarding passengers thanks to the control of the platform and vehicle doors.
  •       ATS (Automatic Train Supervision) is a global control system and centralised traffic management system. It manages the movement of trains in relation to the established exercise program.
  •       ATO (Automatic Train Operation) is an automatic driving system that regulates for each vehicle the journey according to the indications provided by the ATS system and the target stop at the stations. It also automatically controls the movement of the trains, from the start of the route, to the station stop, up to the possible automatic recovery of a faulty train.


The SCADA system – Supervisory Control and Data Acquisition – is capable of managing a huge flow of information, certainly unique among all similar transport systems. To date, in fact, with the opening of the line between Monte Compatri/Pantano–Lodi, 21 stations are operational and for each station there are approximately 7,500 communication points on average. Each single point sends a series of informative messages of the state to the control centre. This results in a total of over one million pieces of information exchanged in real time.


Cameras are installed in the tunnel every 200 m, as well as on the platform and outside. A massive transmission network based on Ethernet – Fiber Optic – WIFI allows the dialogue/exchange of information and the transmission of this on dozens of high-resolution and large size screens at the Central Post with an accurate view of the entire line.

The Granite Depot Workshop and the Central Operational Management

The Granite Depot is located on an area of 20 hectares and was designed with the function of sheltering the entire fleet. Able to accommodate 42 trains, it is 90% automatically managed and equipped with parking areas, automatic washing and underbody blowing zones, as well as preventive and corrective maintenance workshops.

In the heart of the Depot is the Central Operational Post, the command room similar to that of an airport, from which all the operating trains are guided and controlled.

Main functions:

  •       control of train circulation
  •       passenger surveillance for safety purposes
  •       supervision and control of traction electrical systems
  •       communication with passengers on trains and platforms
  •       communication with service personnel online
  •       dissemination of information to passengers (audio-video)
  •       audio – video recording
  •       registration of events and significant operating data of all subsystems

Management assistance systems

For Metro C, original and specific systems have been developed to assist operators in making the management of a complex line safer.


The Decision Support System (ODSS) developed for Line C helps driverless system operators in managing operating conditions both during normal operations and during possible anomaly conditions. This system provides both indications on the correct actions to be implemented and support for implementing them in the most effective way possible.

The ODSS support capacity is based on the use of a knowledge base consisting of the plant configuration, formalised operating procedures, and so-called “Action Cards”, which synthetically represent the already formalised operating procedures.

ODSS can be logically divided into three macro-environments, based on the functionalities made available to the user:

  •       Decision Support Environment;
  •       Maintenance Environment;
  •       Training Environment.

For each of the three issues, the correct procedures to be implemented are presented to the operators.


The Integrated Diagnostic System is an exercise aid system dedicated to the management of Line C.

The DIAG has the function of analysing events aimed at diagnosing the system and operates, in the first instance, on the basis of the information collected and made available through a tool (DAS) that normalizes the information received. This allows integration and proper processing (through filters/correlations). This allows effective identification of equipment malfunctions, causes of failure, and “fault” components. The correlations must take into account the temporal dimension in order to effectively achieve these objectives.

To perform its function DIAG is equipped with tools for:

  •       definition of correlations;
  •       execution of correlations;
  •       presentation of the diagnosis.


The maintenance management system SGM is based on the Carl Source product (of Carl Software) adequately configured, then equipped with some add-ons, accompanied by ad hoc reporting and finally an interface module towards the Normalization Layer. This System analyses how the solution provided can satisfy the matrix of requirements specifically developed for Metro C. The technical report, developed jointly with the technical documents relating to the implementation of the solution, is the basis on which the acceptance tests will then also be carried out.


This system, which operates as an interface between the central ATC and the performance index calculation system (Performance Index Calculator System), is simply called PIC and manages in an integrated way the data coming from the field to provide the values of the system availability parameters (D) and adherence to the schedule (A).

In the development of PIC, the theme of security and privacy was addressed. Access to the application is only after the request and verification of credentials; different user profiles are also anticipated, in order to guarantee exclusive access to the different functionalities of the product. PIC has been designed and developed with the aim of facilitating the interaction process between system and user; the graphic interface is user-friendly, allowing the use of the product even to the user segment without specific IT knowledge.

The system implemented for the “Calculation of Performance Indicators” has the task of providing the necessary information to understand if the operation of Line C of the Rome Metro is taking place as established.

To perform this task, the PIC system calculates the following indicators:

  •       Overall Availability (DO), is the parameter that measures the ratio between the actual operating time, during which the exercise is correctly ensured, and the scheduled operating time;
  •       Technical Availability (DT), like DO but in which the intervals of actual unavailability to restore the fault are taken into account;
  •       Adherence (A) to the exercise schedule.

The PIC system has two modes of calculating indicators:

  •       On-Line: the indicators of Overall Availability (DO) and Adherence (A) are calculated automatically during the operating hours. These values are not final as they are based on the calculation of part of the field data (i.e., those available up to the time of calculation).
  •       Off-Line: the indicators are calculated at the end of the daily operating hours on all field data collected during the exercise.

During the online calculation, the indicators of Overall Availability (DO) and Adherence to the Exercise Schedule (A) are processed at regular intervals that can be configured by an operator with an administrator profile (for example, 5 min.).

The calculation of the Technical Availability (DT) indicator takes place in manual mode, i.e. only after the operator has given the appropriate command. In particular, Technical Availability (DT) can only be obtained following the validation of unavailability intervals by an operator. The main functionalities of the system can be classified into:

  •       Acquisition Functionality;
  •       Processing Functionality;
  •       Consultation Functionality;
  •       Validation Functionality.