Semi-automated vehicle drivers are slower to respond to emergencies than manual drivers, a new study finds.

CLEMSON, S.C. — Assessing safety behind the wheel of a motor vehicle is nothing new. But in a future filled with more self-driving cars, how quickly will drivers be able to regain control should there be a system failure or a sudden emergency? A new study cautions that there is much work to be done.

Automated vehicles aim to allow a would-be driver to conduct any number of tasks instead of having to focus on the road. Whether it’s reading, sending emails or playing a game — owners of fully self-driving cars of the future will potentially be free to enjoy any number of activities that would otherwise be a deadly distraction. But researchers Dr. David Neyens and Dr. Sijun Shen of Clemson University conducted the new study using semi-automated car simulations coupled with a simulated emergency to determine if and when passengers can revert back to driving their vehicles.

The drivers of semi-automated vehicles and self-driving cars are slower to respond to emergencies than manual drivers, a new study finds.
The drivers of semi-automated vehicles and self-driving cars are slower to respond to emergencies than manual drivers, a new study finds.

“As we know, when using technology, things are designed to work well but they don’t always,” says Dr. Neyens in a press release. “So when something stops functioning, how does the driver respond and safely become the driver of the vehicle?”

Forty-eight participants were asked to drive a car in a simulator. Half of the study participants were given a manual vehicle to drive and the other half were given a vehicle that uses several semi-automated functions including adaptive cruise control (ACC) and a lane keeping (LK) assistant. Those in the semi-automated vehicles were then asked to watch five clips cut from an American comedy movie ranging from 40 seconds to one minute in length on the dashboard’s in-vehicle display.

But as the experiment progressed, a strong gust of wind pushed the cars out of their respective lane as part of a simulated emergency to test reactions.

The results showed that both the adaptive cruise control and lane-keeping features in the semi-automated vehicle slowed drivers’ engagement time to regain control of the car. And while manual drivers were able to smoothly take over the vehicle, the semi-automated drivers were more likely to aggressively turn the wheel to compensate for their delay.

Drivers’ reaction times to the lane departure events were even slower when they were distracted by the non-driving task of watching the movie clips.

The researchers say safety standards must keep up with rapidly changing and advancing technology — especially with motor vehicles in which small errors can be the difference in costing lives.

“Autonomous vehicles are a disruptive innovation – they will fundamentally change a lot about the transportation domain,” says Neyens. “Ultimately, we want to improve people’s safety. There’s great opportunity in the semi-automated driving system because there are such huge safety implications: it’s life or death, not just for the driver or passenger but for anyone in the environment.”

“[I]t will become increasingly irrelevant whether a driver can change gear and much more important whether they are capable of responding when there is a system failure,” adds Neyens.

Neyens also warns drivers against “engaging in non-driving tasks requiring extended glances off the forward road,” as was recreated by the viewing of a movie in these experiments.

This study was published in the June edition of the Journal of Safety Research.

About Benjamin Fearnow

Mr. Fearnow has written for Newsweek, The Atlantic & CBS during his New York City-based journalism career. He discusses tech and social media topics on cable news networks.

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