Right now, somewhere in Australia’s Pilbarra – the vast desert mining region that stretches up the lucky country’s western coast – is the world’s heaviest robot. The robot is a 2 kilometres long freight train, and is autonomously snaking its way between mine and port. The train has no driver, but is operated instead using a range of AI enabled cameras and machine learning algorithms which tell it what to do when it ‘sees’ a kangaroo, encounters a level crossing, or needs to adjust its speed to the gradient of the terrain.

If this sounds unusual, driverless trains – also known as autonomous trains – are becoming more and more common – from the metros and trams in city centres to the above AutoHaul technology first pioneered by Hitachi Rail and Rio Tinto in Australia

Here, we’ll look at where autonomous rail transportation has come from, where it is now and take a glimpse into the future of driverless trains.

The path to autonomous trains

By the 1830s, steam locomotives had proved their worth and railways started appearing all around the world. Train drivers were expected to have a pretty advanced knowledge of how the contraptions worked, and how to fix them if they broke down somewhere remote. Indeed, they were referred to as “engineers” rather than “drivers”, and that name stuck in the US and Canada.

Eventually, as rail travel became widespread, train engineering and train driving largely split into two distinct disciplines. Drivers only needed to know the mechanics of driving the train, as well as understanding signalling, keeping to timetables and so on. That split continues today. No modern driver would be required to learn how the microprocessors behind the controls work, and if something breaks, it’s down to engineers to fix it.

The role of the driver narrowed to a more focused set of operations, and some of their responsibilities had been removed. But autonomy was still a long way off. It’s strange to think that powered aviation only took off in 1903, but the first autopilots started being developed in the 1930s, while the railways took well over a hundred years to achieve automation.

Eventually, however, automation would start to become introduced into simple, back and forth rail journeys over short distances. Some started appearing in the 1950s and 60s, such as the Paris rubber-tyred metro and the Barcelona metro, which were partially autonomous. In essence, the technology is pretty simple, and a driver was still required, but the trains would start and stop themselves automatically at the station, as long as certain safety conditions were satisfied.

In 1968, London Underground opened the Victoria Line. As well as being the first underground route to be built in the capital for more than 50 years, it was also the first to have fully automated trains running on it. A driver was still present in the cabin, and there were still manual controls which could override the automation in an emergency, but their main job was opening and closing the doors, something that could not be safely done remotely.

It wasn’t until the 1981 arrival of the Port Liner in Kobe, Japan, that we could finally say the world had a fully autonomous public railway. A similar system opened in Lille, Northern France, a few years later, and now it’s not unusual on light public transit systems around the world.

Today, there is a higher degree of automation than ever on heavy, inter-city and high speed train services. However, just as with aircraft, there is still always a driver or engineer on board, with various levels of control, as well as overall management of the train, rather like a ship’s captain.

Levels of autonomous trains

While full driverless autonomy is certainly technically possible, and is applied on various routes worldwide, it still accounts for only a tiny percentage of trains running today. New trains are still being designed and built with fully equipped driver cabins. But the idea of a train with no automation at all is unthinkable today. The industry has a scale called the Grades of Automation (GoA) for trains, which goes from GoA0 to GoA4, as follows:

• GoA0: No autonomy – all driving done by a human.

• GoA1: A human starts and stops the train, but it can automatically travel in between, with the driver able to intervene in an emergency.

• GoA2: The train drives from stop to stop automatically, but the driver remains in place to override the system if necessary and to perform procedures like checking the platform is clear of passengers before initiating the start sequence.

• GoA3: The train can, and does, drive by itself, but there will always be a person on board, who can take over the controls if needed. They might not be in the cabin, however – they can be checking tickets, making announcements, opening and closing doors, etc.

• GoA4: Full automation – no need for any staff or driver on the vehicle at any time. All passenger safety and driving is carried out automatically.

Why go autonomous?

Are autonomous trains safer?

Although safety was mentioned above as a hurdle to overcome, it is now an argument in favour of automation. Automation, working alongside remote monitoring, on-vehicle sensors, fail-safe computer programming and vehicles and networks designed with automation in mind, brings added safety to railways.

Speed and capacity

Relying on drivers noticing, interpreting and reacting to on-track hazards (including other trains) means that several hundred metres’ distance needs to be between most trains and higher speed trams. With automated hazard management, that reaction and decision time is eliminated, which means they can travel closer together and still stop safely in an emergency. The result is higher capacity, faster rail networks.

Efficiency

Human drivers might be able to drive an electric or diesel train pretty efficiently, but with automation, efficient travel can be looped into the control system. Computers can work out if a train is being driven at its optimum speed, and that acceleration and braking are being deployed to use the minimum of energy. They also help operators to optimise maintenance costs and avoid stressing critical assets on a fleet that could reduce its availability or reliability as a whole.

Better passenger experience 

A driver cabin at the front and back of a multiple unit might take up several square metres of floor space. That room could be used to accommodate more passengers, luggage or bicycles.

The future of driverless trains

Since there are already trains operating at GoA4, we can say that the future is already here - although not at full deployment. Industry has been faster at implementing the technology, however. In factories, ports and warehouses all over the world, there are driverless vehicles, including trains, transporting goods right now.

There’s still something of a psychological misgiving for passengers when it comes to full automation, although that’s one of the hurdles that will be overcome with experience. After all, back in the early days of steam, some experts predicted that travelling at 30 mph would be dangerous to human life. Those same doubters will have gingerly stepped into a carriage once they had been proved wrong and the world was moving on without them.

Another factor standing in the way is that while autonomous trains can be run on existing infrastructure, the fabric of the system will need massive modification. Platforms, railway lines, control rooms and maintenance yards all need substantial investment to perform the upgrade, and such investment isn’t always available. There can be difficulties running a single line that carries both driverless and traditional trains simultaneously, which can make transition problematic. And the fact that autonomy will inevitably lead to a need for fewer staff can make it a difficult policy for local vote-seeking politicians to pursue.

However, when new rail infrastructure is being planned and built, it makes sense to design it with autonomy in mind. The Honolulu Rail Transit Project is being built for this driverless future, for example. It will be the first fully autonomous system in the US, and because it’s being built from the ground up, none of the stumbling blocks mentioned above apply, including workforce issues.

Hitachi Rail also launched a driverless metro system in Copenhagen. A safe, fast and comfortable metro system which pioneers a driverless system - a leading initiative in the transport sector.

The next giant leap will be to apply GoA4 to high-speed intercity passenger trains, although there are few signs of that happening in the short term beyond experimental projects. The technology certainly exists, but the cost of re-engineering large networks might prove decisive.

Will the first pilotless airliner cross the Atlantic before the first driverless train goes from Tokyo to Osaka? Who knows. In public transportation, success depends on taking the people with you.