Drones are handy little things. They can be used to stealthily spy on enemy territory or your neighbor, explore remote locations, protect endangered species from poaching, chase storms, mapping forest fires, and studying Mars, to name a few. In the future, they might even be delivering your packages. But the problem with drones is that they crash a lot, just like the one that recently ended up in a hot spring in Yellowstone National Park. That means that they can litter areas with plastic and metal debris, which not only has the potential to damage the environment, it also informs people that you’ve been snooping around.
The further drones go, the more it might make sense to construct them out of biological materials. A new bio-drone could be able to grow itself in remote locations, and if it gets lost in the wilderness, melt into a harmless puddle.
The shell of the drone is made from a cellulose “leather” to coat the fungal (Mycelium) body of the flying craft and then covered the sheets with proteins sourced from the saliva of paper wasps — a water resistant material that the insects use to cover their nests. Inside, The circuits are printed from silver nanoparticle ink in an effort to make the machine as biodegradable as possible.. Most of the materials—apart from a few components, like the motor—are also biodegradable.
“If it crashes in an environmentally-sensitive place, such as a coral reef, then it can biodegrade and it won’t affect the coral as strongly,” explains Ian Hull, a sophomore at Stanford University, who was part of a large team of students from Brown, Spelman, and Stanford who collaborated with researchers from NASA on the design of the prototype.
“We can also send it into environments where we might not expect it to return,” he says. “If we want to fly it over wildfires to see where it’s spreading, or if there’s a nuclear meltdown and we want to fly in to see what’s going on with the radioactivity, we can send in the drone and it can send back data without returning.”
The mushroom material proved to be well-suited for flying. “Mushroom materials are inherently lightweight, biodegradable, and the strength to weight ratio of the material was preferable for this application,” says Melissa Jacobsen from Ecovative, the company that helped the students make the chassis.
Though the material would naturally biodegrade on its own, the students designed it to self-destruct. “It won’t degrade very quickly unless we give it a set of enzymes that will help break it down further,” says Hull. “Part of our project was making those enzymes that would only trigger upon certain conditions such as impact or time.”
The team is working on making other parts biodegradable and is studying how to build its sensors from modified E.coli bacteria, the bacteria most commonly found in the intestines of humans and animals.
The drone was one of the entries in the International Genetically Engineered Machine competition.
The bio material is also ideal for space, since in can grow itself, no matter where it is.
“The problem with trying to bring anything to space is it’s expensive to take mass up there, and you want anything you bring to be easily modified,” says Hull. “Instead of taking parts and backups, you can just take a tiny sample of the bacteria or fungus you need to grow something like this drone.”
The drone can also use bio-engineered sensors, which can help reduce weight and eliminate the need for electric power. Other bio-engineered cells, developed from organisms that live in extreme environments, help protect the drone from high temperatures and radiation. The students carefully changed the cells so they wouldn’t affect the environment if the drone crashes and melts.
The space applications seem really powerful in terms of harvesting available resources on a planet to grow renewable drones or a colony instead of having to expend fuel to get all the necessary resources there.
Uncertain future use?
Just what kind of “bacteria” will NASA be unleashing on Americans? What effect will it have on humans and wildlife? Will it contaminate land and marine environments resulting in the destruction of ecosystems and species similar to that of the melting starfish in the Pacific Northwest from Fukushima radiation?
War loving America must be very happy about this invention. They can be used to stealthily spy on enemy territory, explore remote locations, protect endangered species… yes, and also to spread bacteria or a lethal virus. (Yo enemy, you friend with the wrong country?
Take a little SARS, Ebola, or Anthrax! Don’t wanna buy our Monsanto corn? Look how I kill all of yours with bacteria’s so you’ll have to… (Just some examples of -IMHO- future uses?)
The short story by Philip K Dick ‘Second Variety’ chronicles how this can go terribly wrong… but what’s the use of thinking of possible apocalyptic consequences of blurring the lines of biological and mechanical technologies!