How Do Driverless Trains Work?

Table of Contents (click to expand)

Driverless trains use a technology called Communication Based Train Control (CBTC), which involves communication between the train and equipment on the track for the management of all rail traffic. This method is more accurate in identifying train positions, bogey alignments, and rail stability than traditional signalling systems. This ensures greater efficiency and safety of both the equipment and the passengers.

By 2050, the number of city dwellers on Earth will reach around 6.4 billion people, doubling where that number stands today. That would mean about 70% of the world’s population will be living in cities. In such a rapidly changing world, the transport system would have to be incredibly effective; there will not be space for human errors.

public, crowd
(Image Credit: Flickr)

The capacities of current mass transit systems can barely be expanded to the extent that will be necessary in the future. In order to make more efficient use of the existing infrastructure, existing metro lines are being modernized and equipped with automatic train control and safety systems.

There has been a great deal of hype in recent years over self-driving cars. Indeed, if such a technology is successfully implemented—namely autonomous vehicles providing the same service that taxis and commercial truck drivers do, but with better safety regulation—it will be a big deal. However, the technology used in these vehicles would require the use of complex algorithms and a skillful understanding of traffic conditions, safety norms, human psychology while driving, road contours and countless other variables that make this proposition more of a challenge.

Google-Self Driving Cars
Driverless car (Image Credit: Flickr)

Driverless trains, on the other hand, are much simpler to design and create than driverless trucks or cars. Navigating a train is simpler, as its path is confined wholly to the rail network. There are only two ways that a train can travel—forward and backward. Hence, the train operator doesn’t need to worry about other trains weaving in and out of its path, unlike someone driving a car.

To begin with, let’s take a look at the prevailing train automation systems.

The Various Grades Of Train Automation

  • Driver-controlled mode: the train is driven without any assistance systems. The driver drives the train based on sight, while stationary light signals control railway operations. This is the prevalent system in train commuting in major cities all over the world.
  • Partly automated mode: the driver still has control over driving and braking the train manually. However, a train protection system continuously monitors its speed. Additionally, statistical information on current movement orders of other trains in the network is continually displayed in the driver’s cabin, for assistance.
  • Semi-automated mode:  the sole job of the driver is to start the engines.  The automatic driving system takes over after that. It has full control over the movement of the train between two stations, including the precise stopping of the train at the platforms and the opening and closing of doors.
  • Driverless mode: The automatic driving system has complete control of the departure, movement between stations, automatic and precision stopping of the train, and the opening and closing of doors. If necessary, the doors can be automatically opened again, according to the system’s analysis of the situation. In the case of high passenger volume, additional trains are automatically sent into operation at the touch of a button. However, an attendant is still present onboard to intervene in emergencies or unusual situations, such as a system failure.
  • Unattended driverless mode: All train operations are entirely controlled and monitored automatically, just like in driverless mode, except that there is neither a driver nor a train attendant onboard. Coupling and uncoupling of trains, stabilizing of bogeys, extended remote control and remote repair options are some additional controls, along with all the controls present in a driverless mode.

Also Read: Will Roads Drive Cars In The Future?

Technology Behind Driverless Automation

driverless train
(Image Credit: Flickr)

The technology employed in driverless trains is called Communication Based Train Control (CBTC). This technology involves communication between the train and equipment on the track for the management of all rail traffic. This method is more accurate in identifying train positions, bogey alignments, and rail stability than traditional signalling systems. This ensures greater efficiency and safety of both the equipment and the passengers.

driverless train..
(Photo Credit: Ryan lin91/Wikimedia Commons)

Conventional metro rails require signalling and the intervention of a train pilot, whereas the function of CBTC-enabled trains is solely based on human-fed data and its own understanding. In most CBTC rail networks, data transfer between trains and trackside equipment is carried out using wireless communication networks, such as the global system for mobile communications-railway (GSM-R) and wireless local area networks (WLAN).

Driverless trains are energy efficient and economical due to optimized acceleration, traction, smooth braking and controlled power intake. Based on line data generated by the control centres, the automated system calculates precisely where and how the train should be accelerated or braked in order to time the arrival and departures with maximum accuracy. Former train pilots can be employed as train attendants to service passengers, and can also act immediately during emergencies.

Additional Features That Make Driverless Tech Successful

To make driverless train tech possible, additional systems like platform track monitoring systems, platform screens, intrusion avoidance and remote sensing systems are essential.

digital board on railway station
Platform screens and data monitoring systems (Photo Credit: Metropolitan Transportation Authority of the State of New York/Wikimedia Commons)

Such systems help eliminate the risk of any fatalities on the tracks and greatly improves system efficiency. If the emergency brakes are deployed by a passenger, the situation in the train can be assessed by the control centre with the aid of passenger area surveillance. Smoke detectors inside the train and on the track report to the control room in the case of fire. This allows the system to understand the situation, devise necessary halts, and quickly re-route the network.

Long-distance Rail Systems

There are certain factors with long-distance railways that are not a concern with urban railway lines, such as animal encroachment, unpleasant weather conditions, and automobiles obstructing the train’s path on the railway.

An elephant crosses a railway track whic
Animal encroachment is one of the biggest concerns in rail transportation (Image Credit: Flickr)

In cases such as these, can driverless trains be successful on railways where the Operations Control Center might be many miles away?

Invariably, yes.

The idea of a driverless rail network not only gives computers control over the systems, but also reaches out to inaccessible places by setting up sensors and detectors throughout the rail line, thus providing efficient and unbiased control over the whole network.

There is always a chance of network failure, as every system has a loophole, but the key is to opt for the system with the fewest holes. Driverless trains with a rail attendant are, therefore, a better option for long-distance rail systems.


Driverless train technology is no longer a new concept for the world’s metro systems, yet it remains something of a contentious issue in the public transport sector.

London’s driverless metro rail (Photo Credit: Au Morandarte/Wikimedia Commons)

On one side, driverless trains are seen as a means of salvation from human error, allowing the industry to achieve new levels of efficiency in the era of overpopulation, where transport is already operating at the very limits of its capacity. On the other hand, critics are apprehensive about entrusting public safety to an unmanned system, not to mention the threat of mass job losses.

All these concerns might be valid in their own right, but the advantages of driverless global connectivity far exceed its cons. What needs to be done is a continual modification of the system, keeping every safety concern in check and monitoring all loopholes in the network.

driver less self car

And… you’re good to go. Get onboard and experience human excellence at its best, even if there isn’t a human driving the train!

Also Read: Are Autonomous Cars Really Safer Than Human-Driven Cars?

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References (click to expand)
  1. Driverless Trains: The Future Is Now -
  2. How do driverless trains work? | Ask a scientist -
  3. Difference between Metro and Local Train.
  4. Self-Driving Cars Explained | Union of Concerned Scientists -
  5. Smart trains with no driver -
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About the Author

Dev is an undergraduate (Bachelor of Science) from St. Xavier’s College (India). He watches a lot of anime and documentaries on the universe and wildlife. He spends most of his time engaging in sports and exercise. He has represented his state at the National Volleyball tournament, in India. Along with that, he has a flair for sketching, photography and would be glad to take up gardening as a career.