Hummingbirds vs. Drone Helicopters: Who Wins?
No, this isn’t the latest blockbuster idea from the SyFy Channel, it’s a genuine piece of research from Stanford University and this fun concept has a serious purpose: improving rescue and operative drones.
The hummingbird is, by most any standard, a marvel of engineering. They can fly at speeds exceeding 54 km/h and male hummingbirds are on record as achieving speeds of almost 400 body lengths a second when, while attempting to woo females, they carry out their spectacular swooping courtship dances. They’re also the only bird that is able to fly backwards and upside-down in a controlled and purposeful way.
Science has long sought to unlock the hummingbird’s secrets, and now researchers from Stanford University planned to see how our best helicopter drones compare to the hummingbird’s superlative speed and maneuverability.
To look into this, the researchers sourced the wings of 12 hummingbird species from a pre-existing museum collection and spun them on lab instruments that are designed to test the aerodynamics of helicopter and drone blades. The researchers also used cameras to look at the airflow around the wings, and instruments called load cells to measure things like drag and lift force.
The researchers replicated the experiment with rotor blades from a ProxDynamics Black Hornet autonomous microhelicopter — the most advanced microcopter currently available for testing, and is also about the size of the average hummingbird.
Not too surprisingly for the Stanford University researchers, the hummingbirds aced every test, though the Black Hornet did manage to come a close second. The researchers found that the Hornet could keep pace in terms of hover speed and maneuverability with the average hummingbird. Even so, there were some hummingbird wings that were simply a cut above the rest, including the helicopters.
In total, the researchers estimate that the best hummingbirds outstrip the efficiency of our best engineered blades by about 27 percent, even though the movement of hummingbird wings requires massive amounts of energy relative to the bird’s size.
“The technology is at the level of an average Joe hummingbird,” lead researcher David Lentink is quoted as saying. “A helicopter is really the most efficient hovering device that we can build. The best hummingbirds are still better, but I think it’s amazing that we’re getting closer. It’s not easy to match their performance, but if we build better wings with better shapes, we might approximate hummingbirds.”
The study, which is published in the Journal of the Royal Society: Interface, left plenty of the hummingbird’s secrets still undiscovered, including how they are able to change direction so effortlessly while in flight.
To that end, here are a few more fascinating facts about these amazing birds:
1. Don’t Get Grounded
Hummingbirds have such tiny feet in comparison to their overall body size that they can not walk on the ground well at all. Instead, in the rare instances that they do land on flat, wide surfaces, they are forced to get around by hopping while using their wings for support.
2. Holy Metabolism, Batman!
Other than insects, hummingbirds while in flight have the highest metabolism of all animals and so must slurp nectar at a furious pace. They need that racing metabolism in order to support the quicker-than-the-eye wing beats that give them their famed powers of hovering and rapid forward flight.
3. A Surprisingly Long Tongue
As you’ve already read, hummingbirds must eat frequently in order to support their racing metabolisms. To help with that, they have very long tongues relative to their body size, and using them can lap up nectar out of a flower at a rate of about 13 licks per second.
4. A Racing Heart
To keep up with all that aerobic activity, the hummingbird’s heart races at the dizzying speed of 1,260 beats per minute.
5. Oh, that Hums!
The sound that the hummingbird makes when it beats its wings is relative to its size and how many wing-beats it can produce per second, and so every single hummingbird species has a slightly different hum. Hummingbirds are also capable of making a chirping noise, though for the most part let their wings do the talking.
If you’d like to find out more about these amazing birds, and see cute videos of baby hummingbirds (you know you want to), please click here.
Photo credit: Thinkstock.