Insect-inspired flexibility makes drones more sturdy.
Drones have surged in popularity in the past few years, both professionally and among hobbyists. One headache with owning a drone is that they’re prone to breaking. Combine small, light weight components with high speed and flying, and you have a recipe for turning an expensive gadget into a jigsaw puzzle on your lawn.
To get around this issue, most drone manufacturers opt for bulky, reinforced components, or flight computers that make them hard to crash. Recently, researchers from Floreano Lab, NCCR Robotics and The École polytechnique fédérale de Lausanne research institute (EPFL) have been designing a new type of drone that avoids damage in an entirely different way. By making the drones flexible, they won’t break on impact, and crashing into the ground becomes less of an issue.
While improving on an existing folding copter design, lead researcher Stefano Mintchev developed a new quadcopter which uses dual stiffness components inspired by insect wings. Insect wings are composed of sections of stiff cuticle combined with joints of the flexible protein resilin that serves as a shock absorber. These two properties working together is what allows insect wings to be flexible while at the same time being load bearing.
The drone is composed of a small central frame with arms of fiberglass held together by magnetic joints. The fiberglass is soft and flexible at only 0.3mm thick, allowing the frame to bend and buckle under force, but without taking permanent damage. Meanwhile, the magnetic joints are sturdy and hold the drone together during flight. The magnets serve another purpose too; upon collision, the force will dislodge them, ensuring that the drone transitions into a “soft state” where the arms and core won’t damage each other. The magnets also ensure that more arms can be added at will, and the drone is not limited to a quadcopter design.
During testing, the drone was dropped over 50 times from a height of 2 meters and no lasting damage was observed on the copter.