This quadcopter changes its geometry in the air to reduce its dimensions and squeeze through tight gaps. Its mechanisms are rudimentary, only hinges and gravity are required.
Increasingly agile and miniaturized,can sneak in almost anywhere. Their limits are those of the arms and the length of the blades which one does not really see when it is a question of passing in a frame of . To introduce via narrow gaps in order to carry out rescue operations, for example, researchers are not lacking in imagination.
CNRS scientists have thus developed a prototype drone capable of modifying itsto squeeze through tight passages. They found inspiration in birds and , capable of this kind of feat. It’s still the which guided researchers from the University of Maryland (United States) to design an autonomous drone whose camera allows it to assess the dimensions of a narrow passage on its own and to sneak in or not.
In the United States, scientists at the High Performance Robotics Laboratory () from the University of California at Berkeley, wanted to create a simpler alternative, with a quadricopter also reconfigurable in flight. The difference is that it doesn’t need small motors or electronics to change its geometry when needed.
This means that only theor the forces exerted on the structure are used to modify the angle of the arms, thanks to a simple system of hinges. The advantage is that the absence of electronics and dedicated mechanisms saves and therefore to maintain the in flight longer. The researchers named their prototype Midair Reconfigurable Quadcopter and they’ve been working on it for over three years now.
On this video, we can see the operation of the drone with its arms equipped with hinges. They collapse when the thrust of the motors is reversed in order to change the dimensions of the drone temporarily. With this technique, the two vertically inclined arms can be used as grippers to transport objects. © University of California, Berkeley
Hinges and gravity as a motor
Concretely, when the drone seeks to enter a narrow vertical opening, the motors of two of the armsreverse their thrust. Consequently, the two arms in question fall vertically. For this to work and for the drone not to turn on itself, the two opposing arms must be offset. This is why the structure of the drone is rectangular and not square-shaped.
With this process, theis temporarily narrower and can squeeze through. Another advantage: with this reverse push and this hinge system, the two arms can be used as grippers and be used to carry objects and drop them or place them elsewhere. As another configuration, it is also possible to fold the four arms to pass through a horizontal breach. Again, the engines all reverse their thrust and the arms are folded down. the falls, but its fall is controlled vertically by adapting the thrust of the engines. As soon as the obstacle is cleared, it can immediately return to its original configuration to stop the fall in its tracks and return to .