Scientists at the universities of Vermont and Tufts have reused living cells, scraped from frog embryos, in completely new life forms, considered living robots. These one-millimeter wide xenobots can move towards a target, perhaps lift a payload (such as a medicine that must be taken to a specific place within a patient) and heal themselves after being cut.
“These are new live machines,” reveals Joshua Bongard, a computer and robotics expert at the University of Vermont, who was the co-leader of the new research. “They are not a traditional robot or a known species of animals. It is a new class of artifacts: a living and programmable organism,” he explains.
The new creatures were designed in a supercomputer at the University of Vermont, and then assembled and tested by biologists at Tufts University. “We can imagine many useful applications of these live robots that other machines cannot do,” says co-leader Michael Levin, who runs the Center for Regenerative and Developmental Biology at Tufts, “such as looking for unpleasant compounds or radioactive contamination, collecting microplastics in the oceans, or travel arteries scraping plaques. ”
This research, for the first time, “designs completely biological machines from scratch,” the team writes in its new study, published in PNAS With months of processing time in the Deep Green supercomputer cluster in UVM’s Vermont Advanced Computing Core, the team used an evolutionary algorithm to create thousands of candidate designs for new life forms. Trying to accomplish a task assigned by scientists, such as locomotion in one direction, the computer would reassemble a few hundred simulated cells in innumerable body shapes and forms. As the programs were run, driven by basic rules on biophysics of what frog skin and heart cells can do, the most successful simulated organisms were maintained and refined, while failed designs were ruled out.
After one hundred independent executions of the algorithm, the most promising designs for the test were selected. Then, the Tufts team, led by Levin and with the key work of the Douglas Blackiston micro-surgeon, transferred the designs to life.
“It’s a step towards the use of computer-designed organisms for intelligent drug delivery,” says Bongard, a professor in the Department of Computer Science and Complex Systems Center at the University of Vermont. Many technologies are made of steel, concrete or plastic, which can make them strong or flexible, but they can also create ecological and human health problems, such as increasing plastic pollution in the oceans.