Radar Helps Drones 'See'

Drones are usually blind-even those carrying cameras rely on a human to navigate safely and spot obstacles. But the octocopter in the video below used a prototype of a new compact, military-style radar system to detect its surroundings and track other aircraft.

As the drone takes off, you can see the traces of barbed wire fences and trees in the radar image on the left. Later, the radar detects another drone nearby and tracks its progress. In other tests the system showed it could detect a small single-propeller plane and an ultralight aircraft.