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Watch a swarm of drones fly through heavy forest—while staying in formation

Weaving through dense woods is a challenge for even the smartest drone. Trying to do it as part of a swarm is orders of magnitude harder. But researchers have now cracked the code.

The approach builds on a single-drone navigation technique, which rapidly maps routes around obstacles as they come within view using only the drone’s onboard camera and computer. The team, which was also behind the earlier strategy, adapted it for swarms by getting drones to broadcast their trajectories over a wireless network. That allowed the other drones to choose routes that avoided collisions while staying in formation.

The technique, published last month on the arXiv preprint server, requires very little computational power and works even if the wireless connection is spotty. In real-world tests, a three-drone swarm was able to move quickly through a forest of randomly spaced trees.

The approach should easily scale up, say the researchers, who have already “flown” swarms of up to 10 virtual drones in computer simulations of tightly packed forests. The technology, they say, could hold great promise for search and rescue missions in disaster zones or surveying ecologically interesting habitats under forest canopies.