Several insects can hover, I bet you saw bees hovering on flower beds looking for the most appealing one for landing and drinking its nectar, birds cannot, with the exception of hummingbirds. I remember spending a few hours in Mexico looking at them and appreciating the hovering that made so easy to photograph them.
Researchers at Purdue have also taken an interest in hummingbirds to learn the technique they are using in hovering because they want to duplicate it in drones. Hummingbirds can hover in place by flapping their wings in a very specific pattern up to 80 times per second and they can move in any direction. Having flying robots able to be as agile would be very useful when operating in closed environment, like in the exploration of buildings after a earthquake.
Now, I would have thought these researchers would use some sort of slow motion camera to understand they way they are flapping their wings. On the contrary, the researchers have created a machine learning algorithm that analyses the hummingbirds way of flying, creates a simulation and the robots uses artificial intelligence to “study” their flight and to adapt and apply it to its own wings.
The robot itself is made with carbon fibre material and membrane cut with laser, with the body 3D printed. The whole weights some 12g, about the same a real hummingbird.
Another interesting feature is the capability of the robot, through sensors and AI, to develop a map of its environment by feeling the changes in the electromagnetic field once it touches (lightly) the various surfaces. This allows operation in a dark environment, like the ones that can be found after an earthquake in search for victims.