Drones have been democratized in recent years, becoming increasingly economical and accessible to all budgets. Their reduction in size has also made these UAVs usable for new uses that are not initially suitable for larger drones.
However, the biggest problem with the ‘microdrones’ continues to be the short time that they can stay in the air due to their small batteries and the little stability they present in the face of turbulence that other objects flying nearby can cause.
Thanks to a discovery, this may change very soon. In a paper published in the journal Science Robots , researchers from Brown University (in Rhode Island, USA) and the EPFL (Lausanne Federal Polytechnic School, in Switzerland) have presented a new wing design for drones that would be capable of to offer a flight autonomy of almost 3 hours, four times more than that of similar drones with conventional wings. These new aerial vehicles that they have conceived would have a weight of only 100 grams.
To create this new design, researchers have simply limited themselves to observing the birds and some insects and the way they fly. It seems that conventional airfoils work best when there is a flow of air sticking to the wing over as much of the surface as possible. If the flow over an airfoil separates from the wing surface, it can cause severe turbulence and loss of lift or control.
However, in the case of many large insects and birds, the separation of the flow is the basis of the way in which they move.
“Small-scale drones have enough sensing and computing power for a growing number of applications. However, flying in the low Reynolds regime remains a challenge. The high sensitivity to atmospheric turbulence compromises the stability and control of the vehicle and the low aerodynamic efficiency limits the duration of the flight ”, the researchers explain.
“Conventional wing designs have so far failed to solve these two shortcomings simultaneously. Here we drew inspiration from the little fliers of nature to design a wing that generates robust lift to gusts and free-flow turbulence without sacrificing aerodynamic efficiency, ”they add.
For now the model has only been tested in a wind tunnel and is yet to be tested in a real environment. However, the team behind the design has patented it and intends to continue improving it.
The PigeonBot, a new drone that carries up to 40 real bird feathers and is capable of folding its wings, has also recently been unveiled. The robot has been designed by Stanford University and has been another great find that could influence the conception of unmanned aerial vehicles in the future.
