Anyone who has spent Christmas morning sending a choo choo around the tree knows the primary hazards to trains are toys wandering onto the track, and taking turns at high speed—both of which are also more or less the primary hazards to trains in real life. So, you might ask, how hard can it be to make trains fully autonomous?
Or maybe you’re wondering why we should even care about trains and how they operate—what is this, the 1800s?—so let’s back up a bit. If you think America is solely dependent on trucks to move freight, you might be suffering from tunnel vision: Trains account for a third of the ton-miles—that is, a ton of weight carried a mile—that freight travels in the U.S. every year. That’s almost as much as is carried by trucks. The U.S. has the most extensive rail network of any country on earth by miles of track—yes, even bigger than China’s—and it’s currently facing some of the same snarls and congestion as seemingly every other part of the country’s supply chains, on account of unprecedented activity at ports and record demand at some rail hubs.
Trains might seem like a mature technology with little room for improvement or expansion, since adding new rail lines is prohibitively expensive, as battles over the cost of the expansion of Amtrak service have shown. But researchers who study the matter say that making them fully autonomous could improve their safety and also significantly increase the amount of freight that can be carried on America’s rail network, by making more efficient use of it.
As the U.S. struggles with truck driver shortages and companies scratch their heads over how to meet their goals for slashing carbon emissions, trains—which are four to five times as efficient in energy used per mile as trucks—could be a two century-old technology whose time has come again.
I’ve written about the limitations impeding grand ambitions for self-driving cars. But trains have qualities that let them steer around those problems. Most important, trains are on tracks, which means an artificial intelligence train engineer doesn’t have to worry about issues affecting drivers of cars or trucks—no tailgating, lane changes, left turns against traffic, and so on.
“We think that trains are going to reach full autonomy faster than vehicles,” says Maxim A. Dulebenets, an assistant professor of civil engineering at Florida A&M University who recently published a broad review of the literature on autonomous trains. One reason: hundreds of passenger trains are operating autonomously in the world already, as part of city metro systems.
The first fully-autonomous subway train made its debut in Kobe, Japan in 1981, and the technology has proliferated ever since, spreading from Paris to New Delhi, and São Paulo to Vancouver. The world’s first fully autonomous freight train, which crosses the Australian outback, was put into regular service in 2019 by the mining company Rio Tinto. In January 2020, China commenced operation of a fully autonomous “bullet” train between Beijing and 2022 Winter Olympics host city Zhangjiakou.
A number of other trials of both passenger and freight autonomous trains are under way. Trials of a German-Dutch autonomous freight train serving the port of Rotterdam began this month. France’s national rail company is currently testing a train that could begin carrying passengers as early as 2023. In the U.S., an autonomous freight train system built by New York Air Brake was tested in the Colorado desert in 2019.
A future of autonomous trains could mean putting a lot more freight onto America’s existing rail network without adding new lines, says Nalin Jain, group president of digital electronics at Wabtec, a Pittsburgh-based train-manufacturing company that traces its roots back more than 150 years. Existing and future technology allows trains to be longer, to run with less distance between them, and to be broken down and reconstituted at ports and rail yards in a more efficient fashion, he adds.