More regularity means improved punctuality. If operations run more smoothly, there are fewer delays, and if they do occur, they can be resolved more quickly.
Any delay is loss
If time is money, then any delay means a loss. In fact, a key concept in transport systems is infrastructure capacity i.e. how many vehicles you can move in one time unit. In railways, delays and unplanned events consume a lot of capacity. One way to improve capacity would be to build more bridges, tunnels and railway lines. But that’s expensive. With an autonomous system you can increase the capacity more flexibly and more cheaply. And if more trains run more on time, then everyone benefits – the economy, the train operators, and the passengers, of course.
So, there are good reasons to automate trains, and the remaining challenges are mostly technical. Individual components have already been proven to work; trains can safely move and stop even if there’s no driver actively steering. It‘s already possible to run a driverless train via signals which are sent to the infrastructure and carried out there.
The difficulty lies in the complex interaction of the various components. When a train is running, multiple subsystems need to interact, monitoring the status of the railway track, the position of other trains and the physical integrity of the train, and determining the space required to brake safely. If any subsystem cannot judge the situation accurately, it will perform defensively: the train will then slow down or stop, and transport performance drops. ETH is currently engaged on various research projects with the Swiss railways to help achieve reliable, performant traffic management systems. We are seeking, for instance, to optimise flow through bottlenecks.
Not just a utopian dream
How many of you have spoken to a train driver lately? In fact, passengers would hardly notice any difference if there were no driver in the cab. The railway system as a whole would be more regular, and there would be more trains available. People would be able to interact directly with the transport system, and move about as much as they wanted, when they wanted. Does that all sound too utopian? Let's not forget – there are already some highly automated driverless vehicles that move a great deal of people worldwide in an unconventional dimension: we call them elevators.