They have the ability to regenerate and can be programmed in the lab. The idea is to serve to clean oceans and also to treat diseases.
By Carolina Fioratti
Jan 14, 2020, 7:02 pm – Posted on Jan 14, 2020, 6:54 pm
Scientists from US universities have managed to manipulate African nail frog cells (Xenopus laevis) to create live robots. Called Xenobots, they are one millimeter in size and are capable of surviving up to ten days in an aqueous environment. The result of the experiment was released last Tuesday (13) in the scientific journal PNAS.
The technology is expected to serve applications such as ocean cleansing – helping with the removal of micro-plastics, for example – or even for human health treatments – such as cleaning arteries and transporting drugs to specific regions of the body.
But first, how was it possible to make a living robot? Initially, the researchers removed materials from the skin and heart of amphibian embryos. At this stage of life, cells have good self-organization skills. Once joined, the cells formed complex three-dimensional mosaics. Then it was just to select the most promising cell phone mosaic formats with the help of a supercomputer – capable of mimicking natural selection.
Taking into consideration the intended tasks – such as moving in predefined directions and carrying small loads – one algorithm generated thousands of 3D projections in different ways that the robot could take. The designs were tested in a virtual environment: the most promising simulations were kept and refined, while those doomed to failure were discarded. In the end, the scientists had about one hundred figures, and took to test those with the highest working potential.
Two formats were successful: the first one is chubby, looking 'legged' like a small octopus. The other, with a hole inside, is what would be used as a bag for loading cargo. You can see both formats in action in the video below.
What differs Xenobots from other normal robots is mainly their ability to regenerate. By breaking the miniature robots in half, researchers identified that they quickly “sewed up” and returned to normal activity. In addition, they are 100% biodegradable: at the end of their lives they become just dead tissue in the environment. This is an advantage when compared to conventional robots made of plastic or metal. Michael Levin, a co-lead scientist, says he believes the same process done with amphibians can also be done with mammals, making life possible for robots in terrestrial environments.
The first reaction that little amphibian-robotic Frankestein causes is astonishment. When entering fields of science that involve life, after all, one must consider aspects of bioethics. Thomas Douglas, researcher of practical ethics at the University of Oxford, however, said in an interview with The Guardian believe that the Xenobots would have a "moral" aspect only if neural tissue was implanted in them. This would enable different types of mental activity, such as the ability to feel pain.
Another question that remains is about the classification of robots: would they be new creatures or just living machines? Does programming them in the laboratory cause them to “lose” their animal nature? Despite the doubts, the study team says it intends to involve bioethicists in future research. For now, showing that this could all be done is enough.