Ground-penetrating radar is used to find land mines; now it can help cars see the road.

The research conducted at the country's National Laboratories is usually highly classified and specifically aimed at solving national security problems. But sometimes you get a swords-into-ploughshares moment. That's the case here, as a startup called WaveSense looks to apply technology originally developed by MIT Lincoln Laboratory to detect buried mines and improvised explosive devices for use in self-driving cars.

If you want a car to drive itself, it has to know where it is in the world to a pretty high degree of accuracy. Until now, just about every variation of autonomous vehicle we've come across has done that through a combination of highly accurate GPS, an HD map, and some kind of sensor to detect the environment around it. Actually, you want more than one kind of sensor, because redundancy is going to be critical if humans are going to trust their lives to robot vehicles.

Most often, those sensors are a mix of optical cameras and lidar, both of which have pluses and minuses. But is a combination of lidar and camera truly redundant, if both are relying on reflected light? Other solutions have included far infrared, which works by detecting emitted light, but WaveSense's approach is truly photon-independent. What's more, it's the first sensor we've come across that should be almost completely unfazed by snow.

That's because it uses ground-penetrating radar (GPR), mounted underneath the vehicle to sense the road beneath—now you can see where the military application was. The GPR scans the ground underneath it to a depth of around 10 feet (3m), running at a little over 120Hz to build up a picture of the subterranean world beneath it. As the car drives along, it compares that data to a map layer of already-collected GPR data for the road network and can place the car to within a couple of centimeters.

Yes, this requires pre-mapping, but so does lidar. And WaveSense says that remapping should be far less frequent as conditions under the road are less subject to change than they are above ground.

It shouldn't even be particularly costly; WaveSense CEO Tarik Bolat told Ars that the sensor should cost around $100 per vehicle, and the technology is already pretty rugged thanks to its first career working in the military. Bolat also said that talks are ongoing with some OEMs and autonomous vehicle programs, although, as is always the case with tech suppliers, he was unable to tell me who at this point.

It's certainly a rather neat application of military technology for civilian use and one that I can see having some added benefits should it be deployed at scale. A near-real-time 3D map of the state of the ground underneath the streets—and all the stuff buried there—should be highly valuable to utility companies and municipalities, if the extent of roadworks around my neighborhood is anything to go by.