Using inductive coupling, scientists have made a breakthrough that allows them to wirelessly transfer power to a drone while it is still flying. The technology could open up a host of possibilities, including allowing drones to fly indefinitely, simply hovering over a ground support vehicle when in need of a recharge.
Inductive coupling is a concept originally demonstrated over 100 years ago by Nikola Tesla, the principle being that by tuning two copper coils into each other with electronics, you can enable the wireless exchange of power at a certain frequency.
Inductive coupling has been experimented with for decades, but until now researchers have failed to utilise the technology to wirelessly power flying devices.
The researchers behind the breakthrough, from Imperial College London, demonstrated their method by altering the electronics and removing the battery of an off-the-shelf quadcopter drone.
A receiving antenna was made by encircling the drone’s casing with a copper foil ring, and a transmitter device on the ground was made out of a circuit board and connected to electronics and a power source, creating a magnetic field. The researchers believe that this is the first demonstration to show how this wireless charging method can be efficiently used with a flying object, and expect it to open up a range of potential applications.
“Imagine using a drone to wirelessly transmit power to sensors on things such as bridges to monitor their structural integrity,” explained Professor Paul Mitcheson, from the Department of Electrical and Electronic Engineering at Imperial College London. “This would cut out humans having to reach these difficult-to-access places to re-charge them.
“Another application could include implantable miniature diagnostic medical devices, wirelessly powered from a source external to the body. This could enable new types of medical implants to be safely recharged, and reduce the battery size to make these implants less invasive.”
Drones are currently limited in their commercial usage by the distance they can travel and the duration for which they can do so.
Despite growing possibilities for usage, the limited availability of power and re-charging requirements means that it is hard to make full use of drones in their capacity for roles such as surveillance or search and rescue. The development of efficient wireless power transfer technology would solve these endurance problems and enable a wide range of advancements.
“In the future, we may also be able to use drones to re-charge science equipment on Mars, increasing the lifetime of these billion dollar missions,” added Mitcheson.
“We have already made valuable progress with this technology and now we are looking to take it to the next level.”
For now, the technology is still very much in its infancy and the Imperial team’s technology only allows the drone to fly ten centimetres above the magnetic field transmission source.
However, they are now exploring collaborations with industrial partners, and have estimated that a commercially available product could be ready in a year.