Driverless trains: the difficult next step

Will autonomous locomotives one day operate outside urban areas?

The take-away

  • The technology exists, but what is holding back development is the risk of accidents.
  • From California to China, totally new concepts are being explored.

In cities, driverless trains are forging their path as technology develops, in line of course with applicable regulations. In Grade of Automation 3 (GoA3) systems, no driver is at the controls, but an operator is on board to monitor door closing and handle any incidents that could disrupt train traffic. GoA4 requires no on-board staff. Starting, stopping and disruptions are handled remotely, for example on Paris metro lines 1 and 14, developed by Alstom. The system has proved successful. With the costs amortised after about 10 years, autonomous metros are both faster and safer. Not one fatal accident has been reported in 30 years.

“Against our morals”

Alstom hopes to take the technology further, says Tanja Kampa, head of the group’s communication for Germany, Austria and Switzerland: “We’ve launched research programmes to explore applications beyond urban underground networks, especially for freight transport and trams.” These applications are rare in Europe and have seen limited development. “Alstom would like to focus on regional transport but is leaning towards driver-assist systems rather than full automation, which remains hypothetical,” Kampa adds, stressing the importance of each local context.

T9 Driverless trains 1920x720 - Driverless trains: the difficult next step

While driverless trains could operate easily between Volkswagen plants, Europe can hardly follow the model of sparsely populated regions like Australia. “The technology exists,” says Anne Froger of the Canadian group Bombardier. “What is holding back development is the risk of accidents. Could we accept a collision between a train and a school bus at a level crossing with no one at the controls? It would go against our morals.” Not to mention the challenge of autonomous trains operating on open tracks, unlike closed underground lines. “When pedestrians have access to train tracks, not having a human in the cab becomes a problem. Only a human driver can tell the difference between a collision with a wild animal and a human tragedy.”

A model for China

Given the challenge of aligning systems with existing infrastructure, some people have advocated building networks from scratch for a new kind of train. The Hyperloop system proposed by American entrepreneur Elon Musk has attracted attention recently, but the project draws extensively on such earlier concepts as the Swissmetro of the late 1990s.

“Although they propose different maximum speeds, propulsion systems and pressure levels, the two systems are based on the idea of driverless capsules operated in reduced-pressure underground tubes,” explains Marcel Jufer, honorary professor at the École Polytechnique Fédérale de Lausanne and the project’s designer. The trains could connect Lausanne to Basel at breakneck speed or reduce the trip from Geneva airport to Lyon airport to a mere 15 minutes. Plans to build Swissmetro have long been stifled by budgetary constraints and competition from other major construction projects in Switzerland. However, these pressurised transport systems have inspired China: a low-speed loop has been undergoing tests since 2014 at Jiaotong Southwest University.

Tanja Kampa (Alstom), Anne Froger (Bombardier), Marcel Jufer (EPFL)