Drones Could ‘Refuel’ On Power Lines

An MIT student is working on a way for unmanned drones to recharge their power supply by perching on power lines like a bird.

Joseph Moore may have to get his skates on if he wants to make something of the idea however: it’s recently emerged that the Air Force Institute of Technology is working on a similar concept, albeit with a different technique.

Both projects aim to deal with the problem that the need to keep drones light means they can only run for a certain period before running out of power, limiting their operating range.

The Air Force plan involves a quad-rotor drone having a trailing hook. The drone would hover over a power line and drop the hook to latch onto it and effectively suck up the juice.

Moore’s technique instead involves the drone itself sitting on the power line. He thinks that if a drone can recharge when needed, it becomes more practical to use a fixed-wing rather than quad-rotor design, which in turn allows the drone to carry more weight.

Unlike the trailing hook design, which might allow a better margin of error, Moore’s design requires more precise navigation so it can land on rather than near the power line. He believes the answer is to use a magnetometer to automatically detect the magnetic field surrounding the power line and steer the drone into position.

The idea is that the drone would have clamps in the position where wheels would be on an airplane. The drone would travel towards the cable and raise its nose on the final approach so it clamps into position facing up an “perching” at around 45 degrees.

It’s very much a hypothetical at this point, and Moore may struggle to fund developing the idea with real drones. However, he has tested the concept with a small, hand-made glider (in effect an elaborate paper airplane) with the magnetometer successfully steering it to within a few centimeters of a mock power line, but not getting it quite close enough to land in the perch position.

(Image credit: MIT)