Manipulating Magnetic Field of the Magnetic Gripper With Charging Feature for Drones on Energized Power Lines

Using drones to inspect overhead transmission lines has progressively gained popularity due to safety reasons, ease of deployment, and reasonable costs compared to the traditional approach of using helicopters. However, the short flying time is the challenging problem that deters drones from being used in long-range inspection missions. Recharging the battery from the magnetic field around the cable is a promising solution that enables drones to operate automatically and endlessly without human intervention. In this article, a magnetic gripper was proposed to take advantage of the magnetic field from the line to hold the drone on the power line and recharge the battery at the same time. A magnetic manipulating circuit with different operating modes was developed to maintain the grip regardless of the power line's current level. The system was tested in the lab and on a drone with an energized transmission line.