Dragonfly, the king of the flying world, scientists have been studying for years, but still have not fully understood the secret of the dragonfly

When it comes to flying animals, many people may immediately think of birds, however, if you want to talk about flight technology, then birds may have to give way, after all, as early as 300 million years ago in the Carboniferous period, insects have already flown into the blue sky, and at that time there were no birds on Earth.

Dragonfly, the king of the flying world

After more than 300 million years of evolution, the insects that exist on Earth have long possessed amazing flight capabilities. Among them, I believe we are most familiar with the mosquito, although we are very disgusted with the mosquito, we have to admit that this insect's flying skills are really strong, in many cases, they will rely on very flexible air maneuvers to easily escape our "clutches".

However, mosquitoes have a lingering "nightmare" - dragonflies, as carnivorous insects, dragonflies love to eat one of the most food mosquitoes, according to the statistics provided by entomologists, dragonflies prey on the mosquitoes success rate of up to 90% or more, which is enough to According to the statistics provided by entomologists, dragonflies have a success rate of more than 90%, which is sufficient to show that the flight technology of dragonflies is far above mosquitoes. The flight technology of dragonflies can be said to be at the top level in nature, and because of this, they are also known as the king of the flying world.

How strong is the flight technology of dragonflies?

Dragonflies can fly at speeds of up to 50 kilometers per hour, which is much faster than most insects. They can quickly come to a standstill and hover steadily in the air while moving at high speed, or they can switch from hovering to high-speed flight in a very short period. During the flight, dragonflies can also make "sharp turns" without warning, and in pursuit of prey, the instantaneous acceleration of dragonflies can reach more than 9g, which undoubtedly greatly enhances their hunting success rate.

Dragonflies can fly in any direction in the air, you read that right, any direction, whether down or up, left or right, and they can even fly upside down.

In addition, dragonflies can also fly very long distances at once, people have long observed that some dragonflies can migrate across the Indian Ocean to Africa, and in 2016, a study by Rutgers University biologists showed that there is a thin-winged dragonfly can cross the Pacific Ocean, and its flight distance can be as high as 6,440 kilometers.

If we had never seen a dragonfly before, we probably wouldn't have imagined that insects with such advanced flying skills could exist in nature. So how do they do it? Although scientists have been studying for years, they still haven't fully figured out the secrets of dragonflies, but there are still many gains, so let's take a look below.

The secret of dragonflies

As the king of the flying world, dragonflies have four huge wings, their wings are very thin, the thinnest part of the thickness can be less than 2 microns, after zooming in, you can see that the dragonfly wings have a special mesh wing vein structure, its "main vein" is a quadrilateral network, while the "secondary veins The "primary veins" are a quadrilateral network, while the "secondary veins" are mostly pentagonal and hexagonal, and scientists believe that this structure gives the dragonfly's wings a strong toughness.

The figure above shows the microstructure of dragonfly wings observed by scientists using scanning electron microscopy, and it can be seen that the surface of dragonfly wings is covered with nanoscale columnar structures, which not only can directly affect the fluid dynamics when air flows over the wing surface but also make the wings of dragonflies have good hydrophobicity and are difficult to get water as well as dust.

It is worth mentioning that in the past, "flutter" has been a major problem for humans in the field of aircraft, and the so-called "flutter" refers to a kind of harmful vibration that occurs in the wings of the aircraft during flight under the combined effect of aerodynamic, elastic and inertial forces. The faster the speed of the vehicle, the stronger the "flutter" will be, and in severe cases, it will even cause the wing to break directly.

Theoretically speaking, such a huge wing as the dragonfly will also occur "vibration", but in fact, the dragonfly is not threatened by the "vibration", why?

After research, scientists found that the reason is that on the front edge of the dragonfly's wings, there is a thickened area called the "wing eye" (shown above), which can effectively eliminate the "chatter" generated by the dragonfly when flying at high speeds. In the following days, a similar structure was added to the wing of the aircraft, imitating the dragonfly, to overcome the "chatter" problem.

Research has shown that each wing of the dragonfly is controlled by separate muscles, and they can also rotate, which means that the dragonfly can individually control the tilt angle of the front and back wings and the amplitude and frequency of wing vibration when flying, and through different phase differences, it can achieve a variety of flight needs.

For example, when the hind wings of the dragonfly are a quarter of a cycle ahead of the front wings, the dragonfly can get a lot of lift and can hover steadily in the air; when the hind wings are 90 degrees ahead of the front wings, it can get a lot of thrusts and fly at high speed; when all the wings are synchronized, it can get the maximum thrust in a certain direction and achieve a "sharp turn"; and when all the wings are synchronized, it can get the maximum thrust in a certain direction and achieve a "sharp turn". "When all the wings stop vibrating, the dragonfly can enter gliding mode, and scientists believe that gliding mode is the secret of the dragonfly's ability to fly over long distances.

Summary

Dragonfly has superb flying technology worthy of the "king of the flying world" this title, and they are also the best teacher of us humans, as of now, although the secret of the dragonfly we still not completely clear, scientists for the dragonfly research have never stopped, look forward to the near future, we can also be like the human flying machine dragonfly Flying in the sky.