A Lightweight Device for Energy Harvesting from Power Lines with a Fixed-Wing UAV

Abstract

Modern UAVs (Unmanned Aerial Vehicles) suffer from restrictions in flight range and time due to battery capacity limitations. One way to overcome these limitations is to harvest energy from overhead power lines. A growing body of scientific literature has documented the development of energy harvesters on multirotor UAVs. However, to date, there have been no implementations on a fixed-wing UAV. In this paper we build upon a previously developed passive perching mechanism for fixed-wing UAVs by incorporating into it a split-core transformer for energy harvesting. We validate the perching mechanism as well as battery recharging in a realistic outdoor environment. We find that a minimum speed of 1.25m/s is required to successfully perch on the power line. This is below the stall speed of the UAV used in this project. Furthermore, experiments verified that no damage was done to the power line during perching, as the induced forces were equivalent to 1m/s wind gusts. Characterization of the energy harvesting shows that with a maximum of 3.3W of power from the harvester, we can fully charge a 2200mAh battery in 2.2 hours. Weighing only 420g, our device is the lightest energy harvester developed to date.