IT’S alive! Well, almost. The first “biological drone”, an autonomous vehicle stitched together largely with materials from living things, made its inaugural flight earlier this month.
Drones have proved invaluable for those who want to explore remote locations, from storm-chasers to the military. But a crash in such a location can not only blot a sensitive environment, it also lets everyone know that you’ve been spying. A bio-drone could potentially avoid that by degrading away in a puddle of inconspicuous goo.
“No one would know if you’d spilled some sugar water or if there’d been an airplane there,” says Lynn Rothschild of NASA’s Ames Research Center in California, who led the team who created the drone.
The bulk of the prototype is made of a root-like fungal material called mycelium. It was cultivated in a custom drone shape by Ecovative Design, a company in Green Island, New York, that grows the stuff as a lightweight sustainable alternative for applications like wine packaging and surfboard cores.
The fungal body has a protective covering of sticky cellulose “leather” sheets grown by bacteria in the lab. Coating the sheets are proteins cloned from the saliva of paper wasps – usually used to waterproof their nests. Circuits were printed in silver nanoparticle ink, in an effort to make the device as biodegradable as possible.
“There are definitely parts that can’t be replaced by biology,” says team member Raman Nelakanti of Stanford University. For example, for its first short flight at the International Genetically Engineered Machine competition in Boston, the bio-drone was equipped with propellers and controls borrowed from a regular mechanical quadcopter. It also has a standard battery.
The next part the team hope to make safe to degrade are the drone’s sensors, and they have already started studying how to build them using E. colibacteria.
Ella Atkins, an aerospace engineer at the University of Michigan in Ann Arbor, is enthusiastic about the bio-drones but warns of trouble if one starts to break down too soon. “We don’t want biodegradable drones to rain down from the sky and we don’t want to litter the land and seas with crashed drones even if they will eventually biodegrade,” she says.