When hungry bats leave their caves at night to feast on insects, millions of these nocturnal mammals somehow manage not to crash into each other. That they manage to do this is astonishing, even without air traffic control asleep at the wheel.

Kenn Sebesta, a researcher at Boston University, wanted to study bats pulling off this nightly, mid-air ballet, so he built an unmanned aerial vehicle (UAV) capable of flying among the swooping colony.

The Batcopter 2.0 (aka "Quady") is Sebesta's home-built quadrotor UAV made from carbon-fiber arrow shafts, twine, glue, zip ties, bamboo and foam which is covered by netting to ensure that any errant bats don't get diced by a propeller.


To film the bats' airshow, a GoPro camera was fastened to the front of the Batcopter, which is remotely piloted from the ground with three high-speed infrared cameras.

To steer the Batcopter, Sebesta and his team used OpenPilot, an open source autopilot platform for small UAVs.

The Batcopter was able to capture terabytes of high quality video of the bats interacting with the UAV. The team is planning to analyze the footage to see if there are any fundamental laws of flight that bats follow to keep them from colliding into each other.