Artificial Flight: Modern drones have become pretty advanced, but they are very energy-inefficient. European researchers decided to take inspiration from birds to develop a new type of drone that could consume less power and mimic its real-life counterpart’s complex movements.

Researchers at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland developed a Robotic Avian-inspired Vehicle for Multiple Environments (RAVEN) by adding hind limbs to a fixed-wing design. The final result is a drone that takes off quicker than a traditional model and performs complex maneuvers that mimic real birds.

The researchers note that birds inspired the invention of airplanes, but even modern planes are far from perfect flying machines. A bird can quickly go from walking to flying into the air and back again instantly. It does not need a runway or a launcher. Engineers have yet to reproduce this kind of biological versatility in artificial designs.

The RAVEN study aims to maximize “gait diversity” while minimizing mass. The bird-inspired multifunctional legs allow the drone to rapidly take off and fly, walk on the ground, and hop over small obstacles. The researchers compared RAVEN to a real raven to display the drone’s capabilities.

Taking off with a jump can “substantially” contribute to the initial flight speed and is more energy efficient than the legless design of traditional drones. The EPFL researchers developed the perfect robotic legs using mathematical models, computer simulations, and experimental iterations.

The project’s final result is an optimal balance between the artificial limbs’ mechanical complexity and the RAVEN drone’s overall weight (0.62kg). The hind limbs keep heavier components close to the drone’s main body, while springs and motors mimic a bird’s powerful tendons and muscles.

Evolution and biology solved the flight problem ages ago with birds, but the researchers had to work hard to try and emulate the same versatility in a drone design. The study suggests that RAVEN’s multifunctional robot legs can expand deployment opportunities compared to traditional fixed-wing aircraft. Thanks to their ability to autonomously take off, the new drones could operate in complex terrains and other hazardous conditions to get their job done.