Autonomous Driving Even Under Bad Weather Conditions 

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Ground-penetrating radar may soon be the sensor that makes cars autonomous in all weather conditions. Developed at MIT Lincoln Laboratory, the technology has proven to be a successful in a military context. MIT’s ultra-wide band radar was first deployed in Afghanistan in 2013. The technology allowed military vehicles to stay on previously-mapped routes by matching radar measurements with maps of subterranean geology. This enabled precise navigation of 9 ton military vehicles, despite unmarked lanes and poor visibility from sand and dust.

Now the MIT Spinoff WaveSense is bringing the radar technology to commercial autonomous vehicles. Adding WaveSense to the existing sensor suite enables autonomous vehicles to see in a whole new dimension and brings a new level of safety to the roads.

How does this dual-use technology work? 

Road subsurface combination of rocks, cavities, culvert pipes, utility infrastructure (cables, conduits, sewer lines), and reinforcing steel bar for concrete (rebar) creates a radar image uniquely different from any other part of the roadway.

The technology maps the environment below the road by combining radar data with GPS tags. Tracking is then performed while the vehicle is in motion by matching the current scan in the prior map.

Ultra-wide band radar uses reflections of underground features to generate baseline maps and then matches current radar reflections to those maps to determine a vehicle’s location and position with centimeter level accuracy.

Ground-penetrating radar can’t be the only sensor in a self-driving car. An autonomous car still needs surface radar, possibly lidar, and cameras to track other vehicles, pedestrians, animals, blocked lanes, and cars stopped or crashed in travel lanes, according to extremetech.com. But it has the potential to be the breakthrough that allows bad-weather autonomous driving.

The ground-penetrating radar could be on autonomous cars circa 2024 and the company believes lidar may not be necessary; lidar is currently the most expensive sensor system on prototype cars. Lidar provides a high-resolution map of what’s around a vehicle, although the range and image are reduced in snow or rain.