Large robots like Boston Dynamics’s SpotMini, as a rule, do not have any special problems with battery power. Due to their large size, voluminous power sources can be installed in them, but it is impossible to place them on tiny insect robots. This is the main minus of miniature mechanisms, although they can be useful for discreet exploration of territories and other tasks that large robots cannot handle. However, Chinese scientists recently managed to create a mechanism that flaps its wings under the influence of sunlight. It turns out that insect robots equipped with such wings can work without batteries – the main thing is that the sun shines.
The new invention of Chinese scientists was described in the scientific journal ACS Applied Materials & Interfaces. The creators of a new kind of wings for tiny robots are professors Ningyi Yuan and Jianning Ding. They called their development Flexible Bio-Butterfly Wing (FBBW), which can be translated as “flexible butterfly wings.” Researchers initially understood that the main drawback of small robots capable of flying is the short time they work due to too tiny power sources. In attempts to create technology that allows such robots to work without batteries, they found a very original solution to the problem.
Robots without batteries
The wings invented by Chinese engineers are made of a polymer film, the upper part of which is covered with tiny metal crystals. Under the influence of sunlight, metal particles heat up the polymer film and cause it to expand. Subsequently, the wing is twisted and the upper part with metal particles is in the shade and the material almost instantly cools. When the temperature drops, the wing takes on its original shape, again allowing sunlight to heat the surface and provoke a new flap of the wings.
As you can see, the technology is simple and ingenious in its own way. By changing the parameters of the wings, the engineers were able to achieve a wave frequency of 4.5 Hz. This is more than the frequency of swings of real butterflies. According to the researchers, with the help of these wings it is now possible to create a small floating machine and a generator that generates electricity from the wings of the “solar wings”. How the operation of these devices looks is shown in the video below.
Unfortunately, an insect robot equipped with new wings does not exist at the moment. But most likely, in the near future they will be used precisely to create such mechanisms. The production of robots of this kind is carried out by Festo. Among their engineering works, there are just butterfly robots, which such wings would not hinder.
But the “solar wings”, of course, have drawbacks. For example, robots equipped with them will not be able to work in rainy conditions, in fog and at night. But scientists say that you can make them move with the help of simulated sunlight. After all, the main thing for their work is not just sunlight, but warm rays that fall at a certain angle.