YOU are driving along when your car suddenly screeches to a halt. As it stops, two children run out into the road, mere centimetres from your bumper, absorbed in a game of tag. You couldn't possibly have seen them, but your car did. And it didn't even use its own sensors.
This scenario is one of the goals of CarSpeak , a communication system for autonomous cars developed by researchers at the Massachusetts Institute of Technology. It lets vehicles "see" out of the robotic eyes of other cars on the road.
A human driver approaching a blind corner must slow down and prepare for the unexpected, but an autonomous car connected to CarSpeak would be able to cruise through, provided with a continuous 3D view of the area created from information captured by other cars, or by a sensor fixed in place to help with the blind spot.
Sending all the information to every car on the road would quickly overwhelm any wireless network. "There are hundreds of cars on the highway, and getting sensory data from all of them would be huge data congestion," says Dina Katabi, project leader for CarSpeak at MIT. "But most of them want to know about what's going on at the next exit."
So, instead, CarSpeak allows cars to request a view of specific sections of the environment that they are unable to "see" themselves, with other cars passing information back to the requesting car. The system works out which regions are facing the most demand and then assigns more bandwidth to those sections as needed, speeding the process up.
So far, the system has been tested on golf buggies in Singapore. Vehicles running CarSpeak navigated through their test environment more than twice as fast as vehicles using simple wireless to relay data, and were 14 times less likely to be involved in a collision with an unseen obstacle. The research was presented at the SIGCOMM  conference in Finland last month.
Swarun Kumar , a lead researcher on CarSpeak, says that the next step will be a larger-scale test with multiple full-sized cars.
Magnus Egerstedt at the Georgia Institute of Technology in Atlanta says it is an exciting idea but it still needs to be proven in real-world situations. "To be completely honest, the sensors in my autonomous cars don't have sufficient range to allow driving on the interstate. CarSpeak has the potential to make that footprint significantly larger."