Despite Advances in Self-Driving Technology, Full Automation Remains Elusive

If our efforts to automate trains are any indication, the cars and trucks of the future may be more dependent on human help than we imagine.

  • More than 50 years ago, efforts began to increase automation in trains. But decades later, humans still remain in the loop.

    Visual: DuKai photographer/Getty

In the visions of techno-utopians and techno-pessimists, the coming decades are filled with taxis, 18-wheelers, and family automobiles all driven by computers. This, despite the fact that today’s self-driving vehicles still struggle with mundane tasks like left turns and highway merges.

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If the past is any guide, however, the cars and trucks of the future may be more dependent on human help than we imagine. More than 50 years ago, automation efforts began on a different type of vehicle — one that suffers far fewer technical challenges, because it moves on rails. I speak, of course, of trains. Decades later, trains of varying levels of automation are now widespread, but humans continue to dominate train cabs. The reasons have less to do with technological challenges than with social and economic pressures. Those same pressures could prevent cars and trucks from ever being fully autonomous.

Experiments with automated subway lines and freight trains date back as far as 1962. Some systems from that era were quite robust; Dallas-Fort Worth’s driverless “Airtrans” people-mover, inaugurated in 1974, served until 2005. Today, driverless-capable track mileage in urban metros is doubling every decade. More than 70 metro lines in 40 cities worldwide are now fully automated, and many more lines support “semi-automatic train operation,” where human drivers open and close doors and press “go.”

Intercity trains have been slower to buy in — big swaths of open track are less predictable than underground or elevated guideways — but Germany and France plan automated passenger lines by 2021 and 2023, respectively, and a driverless freight line in Australia is on track to fully launch by the year’s end. In the U.S., even manual trains now must use “positive train control,” which automatically keeps trains clear of one another and within speed limits.

But even in nominally driverless train systems, humans often pull strings from behind the scenes. Much like Airtrans, France’s “drone trains” will be remotely driven by human “téléconducteurs.” Even the most autonomous systems are supervised by remote operators who can take control of the train if needed. In fact, says Ashley Nunes, a research scientist at MIT’s Center for Transportation and Logistics, “we have yet to find a single example of a safety-critical system or setting where there is no [real-time] human oversight. We can’t find one.”

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Why has it proven so difficult to take the last few humans out of the loop? Part of the reason is that humans have superior intuition for detecting anomalies and responding to exceptional circumstances. Trains are rarely expected to halt for obstacles — the obstacles are expected to keep out of the way — but drivers who are familiar with a route can often catch small problems before they turn into big ones. In New York City, for instance, locomotive engineers and train operators often call in about an unusual sparkle ahead or strange motion over some stretch.

A similar dynamic is emerging in self-driving cars. Although the companies that make autonomous vehicles (AVs) aim for maximum vehicle autonomy, they widely accept that cars will occasionally need to call in human assistance for finer judgment. Silicon Valley startup Phantom Auto offers “tele-operation” for nominally autonomous cars, and manufacturers including Nissan, Waymo, and General Motors are configuring their vehicles to consult humans in difficult scenarios.

But humans’ enduring role in rail stems from more than just their driving skills. Even a fully self-driving train would need people to install and service equipment, respond to failures, and physically couple and decouple cars and cabs. Some trains even need on-board staff at all times: if a passenger train breaks down, for instance, “it’s far better having [a] person on the train and available than leaving 1,300 or 1,700 people by themselves…awaiting someone to arrive,” says Gerard McFadden, engineering director of England’s Govia Thameslink Railway.

Again, self-driving road vehicles will likely face a similar situation. Automated freight trucks, for instance, will still need people to make repairs, manage inventory, and load and unload deliveries — tasks currently handled largely by drivers. Self-driving taxi fleets, meanwhile, will need substantial support teams to address rider concerns or interact with law enforcement.

All that is to say, “driving” comprises a broad suite of activities, some of which are more easily handled by computers than others. And as often as not, the factors that ultimately dictate which activities get automated when have less to do with technology than with economics and politics.

On the economics side, automating rail reduces costs by making it possible for a handful of human workers to oversee a large fleet of trains taking trips at higher frequencies than could be achieved under manual control. For rapid transit and short-range people-movers, where convenience and capacity are king, the potential payoffs of those efficiency gains are huge. That’s less true of longer-range passenger trains, which run less often and require on-train conductors to interact with customers. Freight is in a similar boat: As Dale Lewis, former director of strategic analysis for CSX, puts it, a freight train can already move up to 300 truckloads across the U.S. with just seven two-person crews, “so what’s the payoff for getting the last two people off the train? It’s not a very big number.” A rare exception is the soon-to-be-automated train in Australia, run by mining giant Rio Tinto, which is worth it only because shift changes in the middle of the endless outback are so costly.

Likewise, the areas where autonomous vehicles are making inroads are those where potential efficiency gains are greatest: long-distance trucking, taxi services, and local shuttles. The high upfront investment in automation pays off quickly for large fleets that can be operated continuously with minimal human oversight. Automation is less economical in the private car market, which is why most driverless AV purveyors are not eyeing such sales.

But perhaps the biggest impediments to rail autonomy have been political. For one, there’s the liability issue: Eliminating the driver could leave rail operating companies to shoulder the blame for any incidents. But regulation also plays a role. In the U.S., the regulatory environment does not favor rail automation; in fact, a proposed Federal Railroad Administration rule would mandate a two-person minimum crew in most locomotives.

That proposal belies the influence of another political heavyweight in the automation fight: the labor unions and the jobs they defend. “Even if you had [legal] permission” to cut engineers or conductors, says Lewis, “you’d have to negotiate it with each of the respective unions.” The situation recalls that of “firemen”— the crewmen who fed locomotive steam boilers — after diesel replaced steam: Backed by unions, firemen held on as mandatory crew for over two decades. The jobs issue is especially salient in public transit, Nunes says: “When you’re talking about the public purse, the prospect of jobs being lost is politically very difficult to swallow.”

Autonomous cars and trucks face similar political obstacles. Current rules, holdovers from the pre-automation era, mandate that AVs be equipped with human-friendly features such as pedals. Though that may change soon, legislative bills to encourage autonomous technology in the U.S. have stalled in the face of public skepticism and opposition from safety advocates and unions.

The push to automate trains, then, reveals two truths about autonomous vehicles. First, transportation of any sort is a beast with many arms, not all equally subject to automation. And second, the extent to which the vehicles are automated will largely be a function of economic tradeoffs and political support. With Google sibling Waymo already running a small self-driving taxi service, it remains to be seen — and determined by us — which driving-related roles will be automated and how soon.

Jesse Dunietz is a computer scientist, freelance science writer, and the Technology, Energy, and Society Fellow at Securing America’s Future Energy (SAFE), a think tank focused on energy policy.

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6 comments / Join the Discussion

    Not an ad hominem, a legitimate statement of fact; your English is so poor as to make your arguments unintelligible. Maybe it got lost in the Google translation? Regardless, again, from what I could understand, your position is exclusively political – statements like “America car-centrism (sic – not a word, btw)” kind of give it away.

    Widespread deployment of AVs is coming, it’s inevitable, and it will happen within then next 10-15 years, and there’s really nothing you can do about it. It will be an absolute blessing, will save many, many lives, and will make the world a much better place. Luddite socialists like you who are so pathologically narcissistic as to want to control every aspect of everyone’s lives are just going to have to deal with a world where they don’t get to tell everyone else how to live. “Progressive politics” – if there was ever an oxymoron, that’s it.

    Oh yes I was. My fault, reacting to someone pushing forward their vision, when it’s as strong as to involve ‘bans’ and ‘outlawing’, as the only true without considering any other ones.

    ‘your position is purely political, not scientific’

    Said the person who argues for banning and outlawing, obviously political actions. When…

    ‘The impediment to Level V AVs is the unreasonable and unnecessary requirement that they operate in mixed traffic with non-AV, human drivers’

    …when the actual impediment is the current state of computer vision, mapping, geopositioning, the cost of LIDARs, etc. Kind of demonstrates how ‘scientific’ is your position (so does the ignoring of modern urbanism which is all the rage across the globe).

    ‘Work on your English if you’re going to criticize’

    Haha. Working hard but for just under one year so far, it’s my third foreign language and yes my command of it is still somewhat marred by my knowledge of the other two.
    Before you continue your ad homenem argumentation, how many languages you’re at least remotely fluent in?

    I’m not going to read all that vitriol – your position is purely political, not scientific. “Don’t mix technical requirements and possible impediments.” Huh? “And you have nothing to put up against geometry.” What? Work on your English if you’re going to criticize – at least then we can linguistically understand the point you’re trying to make. Wow were you triggered…

    To the commenter above.

    ‘It would be easy to develop and deploy Level V autonomous vehicles (“AVs”) right now – all you have to do is ban human drivers’

    Don’t mix technical requirements and possible impediments. Developing a true L5 car that can handle all conditions (including heavy fog, rain, snow obstructing its sensors; driving on unmarked and/or unmapped roads; to say nothing of off-road driving) has little to do with banning human driving – by definition. Get your terminology straight. In case of driving ban, even geofenced L4 cars would be enough – given that geofencing covers the operational area needed. But…

    ‘ An environment where all traffic is networked AVs would be easy to implement’

    …but what an ingenuous American car-centrism. Travel the world and see that cyclists and pedestrians do also exist in addition to your beloved cars. That communities can be walkable and public transit can be crazy good. That streets can be walked on freely. You’d say, let’s fence the roads or otherwise keep people from jaywalking and keep the cyclists in their lanes? Naivete. Modern urbanism is focused on dense, walkable, cyclable, mostly car-free communities. Why driverless cars when you can have no cars at all (except for emergencies), huh?

    And you have nothing to put up against geometry. A bus or a tram carry dozens of people, occupying the space of 6 or 8 cars at most.

    What else? Possibly wild fantasies of AVs going at 100 mph within inches of each other? Congratulations, we’ve just invented trains. And few seem to take note of the fact that air drag (=energy consumption) and tyre wear grow dramatically as speed increases. 15 minutes at 100 mph? It’s 25 miles. Come on, we already have trains for that. And they carry hundreds of people. Yes, geometry.

    Door-to-door transportation promised by AVs? For the elderly and/or disabled, yes. For the rest, well-organised public transit. Just as nations encourage walking and cycling, Americans are carried away by the idea which will likely further promote unhealthy lifestyles.

    ‘The result in the US alone would be 30,000 lives saved annually’

    That classic ‘would be’. How do you know? You were sold the yet-unfounded idea by gullible media and now advocate for it. Of course, a fantasised ideal future with near-zero traffic fatalities is better than what we have now. But it’s speculative and the big awkward question is, how can we be sure that this exact ideal future will arrive. Will AVs deliver on their promise of safety? Or will they bring new types of accidents?

    Next, you don’t have to wait for AVs to cut down on that number. Public transit? Walkable neighbourhoods? Built-in breathalyzers in cars? Low-speed streets? ADAS systems (anti-collision, pedestrian detection, etc.)? You name it.

    But okay, for some ardent AV supporters, it may seem worth waiting another dozen years for unclear outcomes… while we can act now. The goal is safety, not AV implementation per se, let alone driving ban. And I certainly don’t want any neurotic ‘ban-it-now’ persons to define the agenda. Driving can be safe, it must be safe, and should persist.

    Cheerz from a European public transit user. Don’t get too car-centric there in the US. It’s a great time to turn the tide back.

    It would be easy to develop and deploy Level V autonomous vehicles (“AVs”) right now – all you have to do is ban human drivers. An environment where all traffic is networked AVs would be easy to implement and would be magnitudes more efficient and safer than human-driven traffic. The impediment to Level V AVs is the unreasonable and unnecessary requirement that they operate in mixed traffic with non-AV, human drivers. Governments should set a date – say, 2030 – after which all traffic will be AV and human drivers outlawed. The result in the US alone would be 30,000 lives saved annually, hundreds of thousands of injuries prevented, and hundreds of billions of dollars in medical and property damage prevented. None of this will be possible, however, if we insist that humans be allowed to continue to drive themselves. This is something the government can mandate easily – there is no Constitutional right to drive a car.

    An additional issue pushing toward driverless cars: Cost of an accident.

    When a train fails to stop or jumps the track you have millions of dollars lost — both to the lost goods/lives on the train, and lost capacity until the track is fixed.

    A Boeing 747 costs 350 million dollars. The salaries of the pilots is pretty small.

    Moving down to a freight truck — the tractor unit is about 100-150K, a 53 foot trailer about 80K The cargo? Another 100-200K. This is why truck drivers only make about 20 bucks an hour.
    Locally one of the more or less continuously advertised jobs is “Swamper” This is a guy who goes with the truck driver to help unload. Going rate is about 3-4 bucks an hour under what the driver gets. It’s worth it to the companies to have a second guy there. This is in the oil patch, where stops are irregular — usually no loading dock, and possibility of hazardous conditions, and often terrible roads for part of the trip.

    Empty driverless cars have some interesting new crimes. Rolling brothels?

    If you are a single woman, who has bought a ride in a car, can you say, “no, don’t pick up anyone else?” What happens with a driverless people mover minivan when one man does a stickup of everyone else in the van?

    Will one of the ‘costs’ of driverless cars be continuous video of the entire interior, stored on a 24 hour chip, and remotely retrievable?

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