So far, plastic, metal and artificial materials have been used – but for the first time researchers have only used living tissue in the design of robots: They have assembled small art organisms from different frog cells that move in a directed manner and can theoretically transport loads. The scientists see potential in the concept: Highly developed “xenobots” could one day be used in medicine or environmental protection.
Humans have long tried to adapt living things to their wishes through breeding or manipulation, and in technology they have copied the concepts of nature. However, this long tradition has taken on completely new forms in modern times: the possibilities of genetics, biotechnology and robotics are becoming increasingly complex and new concepts are being developed. This is exactly what the researchers around Joshua Bongard from the University of Vermont in Burlington have apparently succeeded in doing. “We developed completely biological machines for the first time. They are neither traditional robots nor animals. Instead, it is a new class of artifacts: living, programmable organisms, ”said Bongard.
Computer-designed beings
The building material of the creatures called Xenobots are cells from African frog-type embyos Xenopus laevis, The skills of the art beings made from it come about through a clever combination of immobile skin cells and contracting heart cells. The researchers have used a supercomputer to calculate how these building blocks can be made that enable specific behavior. Using artificial intelligence, he developed certain arrangements of the cells to enable the cell structure to move unilaterally, for example. The researchers then selected the most promising designs for the practical tests.
In order to create the Xenobots, the researchers first removed stem cells from research embryos. These were then grown in the laboratory to obtain the starting material for the construction of the Xenobots. The tissue pieces were then cut using tiny tools and assembled under the microscope according to the computer design. In fact, they then combined into body shapes that nature had never seen before, the scientists report.
As they explain, the skin cells form the passive parts of the approximately millimeter-sized art organisms, while the heart cells make them mobile. They are arranged in the structure so that their contractions cause a directed movement. So the lump-like creatures then wobble forward. The researchers were able to demonstrate that the xenobots can explore an aqueous environment for days. They even have the ability to heal themselves: “Even if you almost cut them up, they then sit back together and keep running,” says Bongard. “Of course you can’t do that with normal machines.”
Potential is emerging
As the researchers report, they found that groups of xenobots begin to circle. This allows you to move objects to a central location, for example. The scientists also built other xenobots with a hole in the middle. This could act as a bag to transport an object, the researchers say. “This is a step in the direction of using computer-designed organisms for intelligent drug delivery,” says Bongard.
As the researchers emphasize, the prototypes have so far only been a feasibility study. But they see considerable potential in further developed xenobots: “We can imagine many useful applications of these living robots for which normal machines are not suitable,” says co-author Michael Levin from Tufts University in Medford. “You could look for dangerous compounds or radioactive contaminations or collect microplastics in water.”
In addition, applications in medicine are conceivable: “The small creatures could migrate through arteries to scrape out plaque,” says the scientist. The great advantage compared to previous nanorobot systems is that the xenobots are not made of problematic plastics, but are completely biodegradable. So it will be interesting to see what will develop from the bizarre-looking approach.
Source: University of Vermont, Technical article: PNAS, doi: 10.1073 / pnas.1910837117