When traffic is heavy, a single car slamming on the brakes too fast or speeding up too quickly can both waste fuel and slow everyone down. Now, a joint project by Honda and the University of Tokyo could reduce traffic congestion by giving drivers real-time feedback. The system, which will be tested next month in real traffic situations, gives drivers a color-coded display that lets them know whether their acceleration and braking patterns are likely to encourage smooth driving or if they might be causing traffic to slow down by making other cars start and stop erratically. If the terminal is connected to a larger cloud network, it can collect patterns from other cars as well, feeding them into a cruise control system that helps keep vehicles a safe distance apart as in the diagram above.

In trials so far, researchers found that the display (even if it wasn't connected to the larger network) increased overall speed by about 23 percent and fuel efficiency by about 8 percent in vehicles behind cars that had it installed. In May and July, the systems will begin open-road tests in Italy and Indonesia respectively. Cruise control that can react based on the placement of other cars sounds fairly futuristic, but a lot of this experiment seems based on the simple principle of making drivers aware of what they're doing on the road.