2023 Author: Bryan Walter | [email protected]. Last modified: 2023-05-21 22:24
German engineers have created a miniature robot controlled by a magnetic field. Due to the external field, he can swim, walk on hard surfaces, and also grip and move objects. The current modification is about three millimeters long, but in the future, researchers plan to significantly reduce it and create a robot for medical purposes, according to a paper published in the journal Nature.
Conventional electric motors are difficult to scale for miniature robots, so engineers are working on other ways to drive them. The most convenient and widespread method among such developments is control using an external magnetic field. Such robots do not need to carry a motor and a battery, and they can work even in the absence of contact or direct line of sight with the emitter, due to which they can be used for manipulations inside the body. But magnetically controlled robots also have disadvantages: they only support a limited set of movements and environments in which they can move.
Researchers led by Metin Sitti of the Max Planck Institute for Intelligent Systems have developed a much more versatile magnetic robot. It is a rectangular strip of silicone elastomer with magnetic particles of neodymium, iron and boron with an average size of about five micrometers. These particles are magnetized in such a way that their magnetization vectors in the strip have a harmonic profile.
Distributions of the vectors of magnetization of particles in a strip
Since the magnetization in the strip is unevenly distributed, it begins to bend in an external magnetic field, and the magnitude and direction of the bending depends on the magnitude and direction of the magnetic induction vector. Thus, the engineers "taught" the robot to perform complex movements: walk on a hard surface, swim, dive into water, climb the meniscus of the liquid and crawl along narrow tubes.
In addition, the developers taught the robot to grab and move small objects, as well as jump, dramatically changing its shape and pushing off the surface.
Engineers note that while the robot will be used for research purposes, for example, studying motion at the boundaries of non-Newtonian fluids or bulk media. In the future, they plan to significantly reduce the size of the robot and test it inside living organisms.
Last year, American researchers created polymer cubes that can be combined into a microscopic robot under the influence of a magnetic field. It can move through liquids or capture objects, including living cells. And other researchers have created microrobots that can also move and grab objects, but do so when the temperature changes, and not due to an alternating magnetic field.