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Robot cars could triple highway capacity

A new study says a fleet of self-driving cars would be far more efficient than a bunch of error-prone humans.


The future could look something like this. Well, sort of.

We’ve been hearing an awful lot about robot cars over the past year or so—about how they’re quickly advancing and will soon be here—but there have been few hard numbers on why we’d actually want them. Sure, self-driving cars offer the promise of making long road trips more productive and enjoyable and they’ll go far in eliminating road rage. But surely the developers behind such vehicles must think there’s more behind it than that if they’re going to go to all that trouble, right?

Some new research out of Columbia University, presented to the Institute of Electrical and Electronics Engineers conference on vehicular technology last week, hits that sweet spot. According to the study by Patcharinee Tientrakool, a fleet of self-driving cars could nearly triple the capacity of our highways.

She believes that a lone robot car that is able to manage its own speed would see an efficiency gain, in terms of fuel and time spent, of about 43 per cent. But the gains would really become apparent when the autonomous vehicle is pooled with similar-minded robot cars that it can communicate with. After all, a single robot driving on a highway full of actual people still has to contend with an awful lot of dumb humans.

If all the cars on the road are robots, however, things can really speed up. The report envisions the same sort of bumper-to-bumper traffic we currently experience on highways at rush hour (or here in Toronto, basically all the time), but the swarm would be moving at a much faster speed. Humans generally stay a second and a half behind the car in front of them; a robot could close that gap considerably, thereby allowing for a higher density of vehicles on the road.

This is the sort of thing that’s music to the ears of not only commuters, but city planners, road builders and politicians. Here in Toronto, our city council and mayor should perhaps spend a little more time thinking about how to implement robot cars and a little less on arguing about whether to build subways or light rail transit.