A team of experts at the University of Texas is developing technology that allows for wireless charging of drones mid-air using electromagnetic waves.
The U.S. Defense Advanced Research Projects Agency (DARPA) is committed to further funding long-range wireless power transmission technology, also known as wireless charging, to recharge drones while they are in flight, enabling them to maintain their missions without the need to land for recharging or changing depleted batteries, New Atlas reported on May 28.
MQ9-Reaper Drone. (Photo: General Atomics).
Dr. Ifana Mahbub, an associate professor of computer and electrical engineering at the University of Texas, received the Young Faculty Award from DARPA in 2021, providing her project with $500,000 over two years. She is currently receiving an additional $250,000 to continue developing the wireless charging technology.
Wireless charging technology is not new. Some mobile phones use near-field wireless technology to charge batteries via low-frequency electromagnetic waves over very short distances. The charger consists of a coil that generates an electromagnetic field. The receiver, such as a coil in a phone, captures these electromagnetic waves, generating a current that is then directed into the battery.
Mahbub and her colleagues are researching long-range field technology to transmit electromagnetic waves much farther. One of the biggest challenges is preventing electromagnetic beams from dispersing and losing energy over long distances. Mahbub came up with the idea of using a phased-array antenna system, consisting of small transmitters and antennas that help steer the electromagnetic beam along a specific path. The new technology utilizes the drone’s real-time remote sensing capabilities to ensure a direct transmission connection, thereby achieving maximum charging efficiency.
Military drones, such as Medium Altitude Long Endurance (MALE) types, are designed to fly at altitudes up to 25,000 feet (7,620 meters). High Altitude Long Endurance (HALE) drones typically operate at 50,000 feet (15,240 meters). Meanwhile, tactical drones usually fly at altitudes of about 2,000 to 5,000 feet (600 to 1,500 meters).
While it may sound daunting to project strong electromagnetic waves to charge a small aircraft mid-air, humans have long been doing similar things. Broadcasting, television, mobile phone services, radar, Wi-Fi, and even GPS all utilize electromagnetic waves.
In addition to charging drones in flight, the new technology has many other potential applications, such as charging electric vehicles while they are on highways. Mahbub is also researching wireless charging technology that can be used at low frequencies and safely, enabling the charging of medical implants in humans.
