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Driverless Cars vs. Potholes

By March 14, 2018No Comments

When autonomous vehicles come upon a pothole they don’t react like a human. Emerging technologies could solve this problem, but there are ethical issues to iron out.

Chess-playing computers have been able to beat humans at the game since at least 2005. But car-driving automation (some call them driverless or autonomous vehicles) is something else. Programmers haven’t fully figured out how to make the rule-bending decisions that humans make on a daily basis to avoid potholes.

Consider how drivers sometimes break the law to avoid accidents. In a split second a driver may recognize the pothole in his or her path, then swerve out of the lane to avoid it. The driver is acting on the perception of no traffic around the car that will be adversely impacted by the swerve (or making a mistake due to a mirror blind spot – or by just taking a risk). But a driverless vehicle, programmed to adhere to all laws, will rapidly slow down so as to hit the pothole with less force.

Which is bad news for tailgaters. It’s a worrisome scenario – a lot of quick braking and sometimes, despite best efforts, rear-end collisions and damaged rims and flat tires. Just slowing down for a pothole doesn’t always prevent damage.

If we expect innovation in cars, we should expect innovation on one of the most vexing problems faced by car drivers: potholes. Yes, engineers are working on car resiliency to rough pavement problems. Here’s what they are coming up with:

Visual sensors: An online forum sponsored by Tesla, the electric vehicle company actively engaged in disruptive automotive technologies, covered the topic of vision-based autopilot functions and road hazards. “How will autopilot handle potholes? What if there is a puddle covering the sides of the road, because in my [car] it does not allow me to pull into the puddles?,” asked a current Tesla owner.

Respondents to the question acknowledged the cameras and sensors currently mounted on the bottom of the company’s cars aren’t designed to distinguish between puddles and potholes. Some described a future where the sum of all cars will upload potholes and other pavement problems to a shared cloud database, with the collective data guiding traffic to avoid them. Presumably, when the pothole is fixed there will be other sensors making note of that; the corrected information will go back up in the cloud so the autonomous vehicles know the pavement is clear for traffic once again.

Laser pulses: Tesla is hardly the only company working on this. Google’s Waymo driverless vehicle uses Lidar, which employs laser pulses from the car roof (a “puck,” which looks much like a police car’s bubble light). Lidar can spot moving and stationery objects, but is still in development stages to bring down costs (currently $4,000 per vehicle) and improve resiliency. Says Wired magazine’s transportation writer, “Anything going into vehicles has to be robust and reliable, able to withstand a life of potholes and temperature extremes, and it has to keep working for years.” Uber, Toyota and other firms are participating in tests of Lidar.

Continuously controlled damping: With cloud-based machine learning systems, there still are those first vehicles that find the pothole when it first forms. Must there always be one or two or twenty sacrificial cars to help inform the cloud and subsequent drivers?

The future may already be here in this respect – and available to human drivers who may not have seen that pothole coming. What’s in use in a few models are dynamic suspensions systems (also known as “continuously controlled damping” systems) that essentially turn a vehicle into a three-wheel conveyance for a few moments. In simple terms, one wheel sees the pothole, tells the car’s controls, which then effectively takes the vehicle weight off that wheel for the time it takes to pass over it (a mere second or two).

Adaptive suspension systems: Continuously controlled damping systems are already found in the Ford Fusion V6 Sport (beginning with the 2017 model). The Lincoln MKZ has had such a system since 2014, and Mercedes-Benzes (C-Class, E-Class, GLC-Class, GLE-Class, S-Class, CLS-Class, GLS-Class, and SL-Class) have something called an AIRMATIC suspension, which uses adjustable air springs in place of traditional steel springs. The Mercedes-Benz AIRMATIC works together with an adaptive damping system similar to those in the Lincoln and Ford Fusion models. According to Cartelligent, a car-buying review website, adaptive suspension systems are also available in certain models from other manufacturers, including: Acura (sport hybrid models), Audi (2017 A4 and 2018 S4, A5 and Q5), BMW (5 series, 6 series, X6 and most Alpine models), Buick (LaCrosse), Cadillac (ATS, CTS, and XTS), Dodge (Charger and Challenger), Genesis (Yukon and Sierra 1500), Infinity (Q50 and Q60), Jeep (Grand Cherokee SRT), Land Rover (Discovery Sport and Range Rover Sport), Porsche (Cayenne), Toyota (Sequoia), Volkswagen (Golf R), and Volvo (XC90).

So how exactly do these floating wheel systems work when pitted against potholes? A chassis engineer with Ford told WTOP-FM in Washington, DC the tire “doesn’t strike the edge [of the pothole] as hard, so you don’t get that harshness and jarring feeling.” Resulting in fewer, we assume, ripped up tires that cost $100+ to fix or replace.

The ethics of driverless vehicles

Way back in 2013, The Atlantic magazine considered the ethics of programming driverless vehicles. Programmers are the people who essentially determine what happens when the autonomous car encounters a pothole. “There are many examples of car accidents every day that involve difficult choices,” says the magazine writer, describing the swerve-or-hit scenarios involving animals, poor pavement, other cars and pedestrians. “Human drivers may be forgiven for making an instinctive but nonetheless bad split-second decision. But programmers and designers of automated cars don’t have that luxury, since they do have the time to get it right and therefore bear more responsibility for bad outcomes.”

Heady stuff, to be sure. But for now only a small percentage of vehicles currently have continuously controlled damping suspension systems. It’s a costly addition to many cars, with and without drivers. So most of us are likely to incur expensive damage from potholed pavement for some time to come.

Maybe just fixing the roads – with proper maintenance and better asphalt – will affect more people and sooner than cool technologies.

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