I have an article in Fortune that looks at the hype surrounding autonomous cars. Here’s a bit from the piece highlighting recent research that calls into question some of the common assumptions about robotic vehicles:

At a car conference last September, Steven Shladover, a research engineer at the University of California at Berkeley, explained that automotive automation presents far more daunting challenges than aircraft automation. Cars travel much closer together than planes do, they have less room to maneuver in emergencies, and drivers have to deal with a welter of earthly obstacles, from jaywalkers to work crews to potholes. Developing a driverless car, Shladover said, will be orders of magnitude harder than developing a pilotless airliner. It’s going to be a long time, he cautioned, before we’ll be able to curl up in the back seat while a robot drives us to work.

Even if perfect automation remains beyond our reach, progress in automotive robotics will sprint forward. Top-end luxury cars are already highly automated, able to center themselves in a lane and adjust their speed to fit traffic conditions, and computers are set to take over many more driving tasks in the years ahead. As always, though, the road to the future will have many twists and forks. The choices that companies and designers make in automating cars will influence not only how we drive but how we live. As we learned in the last century, advances in personal-transportation technologies can have profound consequences for everything from housing to urban planning to energy policy.

Consider safety. It’s often assumed that automation will reduce traffic accidents, if not eliminate them entirely. But that’s not necessarily the case. Research into human-computer interaction reveals that partial automation can actually make complex tasks like driving more dangerous. People relying on automation quickly become complacent, trusting the computer to perform flawlessly, and that raises the odds that they’ll make mistakes when they have to reengage with the work, particularly in an emergency. A study of drivers by U.K. scholars Neville Stanton and Mark Young found that while shifting routine driving chores to computers can reduce workload and stress, it also “lulls drivers into a false sense of security.” They lose “situational awareness,” which can have tragic consequences when split-second reactions are required to avoid an accident.

The risks will likely be magnified during the long transitional period when automobiles with varying degrees of automation share the road. Given that the average American passenger vehicle is more than 11 years old, there will be “at least a several-decade-long period during which conventional and self-driving vehicles would need to interact,” report Michael Sivak and Brandon Schoettle of the University of Michigan’s Transportation Research Institute. That becomes particularly problematic when you take into account driving’s complex social psychology. When we change lanes, enter traffic, or execute other tricky maneuvers, we tend to make quick, intuitive decisions based on our experience of how other drivers act. But all those deeply learned assumptions may no longer apply when the other driver is a robot. Just the loss of eye contact between human drivers, Sivak and Schoettle warn, could introduce new and unexpected risks, particularly for drivers of older, less automated cars.

Beyond the knotty technical questions are equally complicated social ones. Peter Norton, a transportation expert at the University of Virginia, points out that the way autonomous vehicles are designed will have a profound influence on people’s driving habits. If automation makes driving and parking easier, and in particular if it allows commuters to do other things while in their cars, it could end up encouraging people to drive more often or to commute over longer distances. Cities and suburbs would become even more congested, highway infrastructure would come under more stress, and investments in public transport might wither further. “If we rebuild the landscape for autonomous vehicles,” Norton writes, “we may make it unsuitable for anything else — including walking.”

On the other hand, if we design autonomous vehicles as part of a thoughtful overhaul of the nation’s transit systems, the new cars could play a part in reducing traffic, curtailing air pollution, and engendering more livable cities. It’s a mistake, Norton argues, to view autonomous cars in isolation, and it’s an even bigger mistake to assume that automotive automation will be a panacea for complex problems like traffic and safety. “Before we make autonomous cars the solution,” he says, “we must formulate the problem correctly.”

Image: US Department of Transportation.