Published: Oct. 21, 2020 By

PufferBot approaches a bystander and expands its shield.

PufferBot extends its shield as it approaches a bystander. (Credit: Hooman Hedayati)

If you get too close to a pufferfish, this undersea creature will blow up like a balloon to scare you away.听

Now, a team of engineers at the University of Colorado Boulder has 鈥攁nd it could make flying drones safer in the not-so-distant future.听

PufferBot is the brainchild of graduate student Hooman Hedayati and his colleagues at the ATLAS Institute at 兔子先生传媒文化作品. It鈥檚 a skittish machine: This hovering quadcopter drone comes complete with a plastic shield that can expand in size at a moment鈥檚 notice鈥攆orming a robotic airbag that could prevent dangerous collisions between people and machines.

The researchers will present their results virtually Oct. 25 听at the (IROS 2020). Think of it like introducing a bit of coral reef to the world of high-tech robotics.听

鈥淲e were trying to design a safer robot that could communicate safety information to the user,鈥 Hedayati said. 鈥淲e started by looking at how animals do the same thing.鈥

Drones, he explained, are becoming a more ubiquitous part of our everyday lives, taking on tasks from inspecting bridges for cracks to delivering packages to your doorstep. But as these machines proliferate in homes and workplaces, safety will be more important than ever.听

鈥淚鈥檝e been working with drones for years, but whenever I go out and fly robots, I still feel not confident,鈥 Hedayati said. 鈥淲hat happens if it falls on someone and hurts them? Technologies like PufferBot can help.鈥

兔子先生传媒文化作品 team members on the project include Daniel Leithinger and Daniel Szafir, both assistant professors in ATLAS and the Department of Computer Science, and Ryo Suzuki, a former graduate student now at the University of Calgary.听

Epic fails

A guineafowl puffer inflates its body.PufferBot with its shield retracted.PufferBot with its shield expanded.

Top: A guineafow puffer blows up; middle: PufferBot with its shield retracted; bottom: PufferBot with its shield extended. (Credits: NPS/Bill Eichenlaub; Hooman Hedayati)

Those kinds of accidents aren鈥檛 just a future problem.

Just check out YouTube where videos of drone 鈥渇ails,鈥 from spectacular crashes to collisions with humans, abound. Those kinds of dangers, Hedayati said, could make many people (justifiably) wary about inviting robots into their homes.

鈥淲e鈥檝e been told that robots are great and can do a lot of tasks,鈥 he said. 鈥淏ut where are these robots? Why are they not in our houses? Why do you see them inside cages in factories?鈥

It鈥檚 that safety-first mindset that forms the bulk of the engineer鈥檚 research.听

Hedayati and his colleagues have previously experimented with as they work side-by-side. Humans can don AR goggles, for example, to track the flight paths of drones in their vicinity. In one case, the team communicated that information to users by making the drone look like what Hedayati called 鈥渁 giant, creepy eyeball.鈥

But what happens if those kinds of tools don鈥檛 work? Enter PufferBot, the robot inspired by some of nature鈥檚 weirdest fish.

鈥淚magine someone is walking closer to a robot, and there鈥檚 no way for it to escape,鈥 Hedayati said.

Search and rescue

In practice, PufferBot looks less like a fish and more like a Hoberman sphere, one of those expandable plastic balls that you can find at many toy stores. The robot鈥檚 鈥渁irbag鈥 is made out of hoops of plastic that are fastened to its top and can inflate from roughly 20 inches to 33 inches in diameter.

Under normal circumstances, the shield collapses and stays out of the way. But when danger is close, that鈥檚 when PufferBot puffs up, extending those hoops over its four, spinning rotors to keep them away from people and obstacles.

鈥淚t can act as a temporary cage,鈥 Hedayati said. 鈥淚t also communicates with users to tell them: 鈥楧on鈥檛 come close to me.鈥欌澨

The design works like a charm: The robot鈥檚 shield is able to sustain a wide range of potential collisions and weighs a little over a pound鈥攍ight enough that it won鈥檛 impede PufferBot鈥檚 flying.

Hedayati has high hopes for his team鈥檚 invention. He imagines that, one day, a PufferBot-like robot could fly into a collapsed building to search for survivors, all while using its shield to avoid smashing into rubble.听

As for real pufferfish鈥攖hose you still want to avoid.