Columbus, Ohio — When you imagine a robot, slithery snakes and huggable koalas may not come to mind. But innovative teens have been using “soft” robotics to create such bio-inspired machines. Their inventions can return a warm hug or assist in the rescue of people trapped in building rubble.

An earthquake on March 28 trapped hundreds of people in the ruins of collapsed buildings in Myanmar, a country in southeast Asia. Nichelle Thinagar, 16, saw this disaster on the news. “There were so many more people left unaccounted for, trapped under rubble,” she recalls. Stories like this compelled her to design rescue robots. But Nichelle’s come with a twist — a smooth, serpentine twist.

Imagine a snake slithering your way. Nichelle modeled her rescue-bot after these limbless wrigglers. And for good reason. Scale-covered snakes evolved to wiggle through tiny cracks. One secret to their slithering, the sophomore at Shrewsbury High School in Massachusetts learned, were those scales.

She tapped this design feature to enhance her snake-bot’s motions. “The most recent design has … ball bearings embedded directly into the scales,” she says. This aids the forward gliding motion. Her project earned Nichelle a finalist slot here at the 2025 Regeneron International Science and Engineering Fair (ISEF).

“A snake’s scales are very smooth from head to tail,” Nichelle says. That lets them glide forward. A little backwards pressure, however, allows those same scales to dig into the ground. “That lets them push themselves forward,” she says.

Nichelle didn’t invent snake-shaped robots. But she did make unique use of nature’s scale-grip technique. That allows the bot to move “like a real snake.” Nichelle hopes her slithering device will help it navigate building rubble. Another feature that sets her robot apart from others: A small compartment in its head can haul water or other supplies.

Simulated problems require real-world answers

Nichelle hoped to test different scale designs with computer simulations before building a full robot. But that plan didn’t work. The tests she needed, she realized, were just too complex for her to model. She needed data. And the only way to get those was by testing.

For instance, she needed to measure her snake skin’s coefficient of friction. That’s “basically the stickiness between two surfaces,” Nichelle explains. “Like the stickiness between my scale design and the surface below it.”

Many factors play into how different scales slide across surfaces, she learned. “That’s just something that the simulation software couldn’t compute.” To test snake scales, she had to build a snake wearing them.

Nichelle 3-D printed the scales and all the other robotic components. A cable system runs throughout the snake and triggers muscle-like wriggly actions. Instead of the “normal, rigid components you’d see in your typical robot,” she explains, “it uses more soft structures that resemble things like muscles.”

A tether connects the robot to the person controlling it. “A lot of urban rubble is reinforced concrete, which blocks communications,” Nichelle says. Using a tether means the operator won’t lose connection with the robot. It also allows the rescuer to communicate with survivors.

Here come the hug-bots

Tim Wilson, 18, designed a soft robot for a very different purpose: to give reassuring hugs. His inspiration was his sister’s frequent trouble getting a good night’s sleep as a child.

“I saw the impact of poor sleep on the rest of her life,” he says. Friends in school described similar problems. “We’d chat about how they couldn’t fall asleep,” he says. When it came time to do a high-school research project, he decided to tackle “a real need in the world.” His solution — a huggable, co-sleeping robot — brought this student at Barker College in Sydney, Australia, to this year’s Regeneron ISEF. It also garnered Tim a First Award in the Robotics and Intelligent Machines category.

Other robotic sleep aids exist. But until now, none could hug you back, Tim says. He started by building a monkey-bot. He went on to create a koala, too.

Hugging the robot triggers the arms to return the hugger’s embrace. They squeeze back thanks to inflatable, flexible tubes in the robot’s arms. A fiber outside the tube works like a muscle. In robotics, this part of the device is called the actuator. “An actuator is just something that creates movement,” Tim explains.

His machines do more than return hugs. They also mimic breathing. The toy’s chest gently rises and falls. It’s “quite soothing,” Tim says. The robots even try to match their “breathing” rate to the hugger’s. How? A sensor inside measures the carbon dioxide exhaled by the hugger. The robot then “tries to mirror how fast you’re breathing.” Tim says that part proved tricky. After all, a bedroom fan might be enough to throw off the gas levels. “It’s not always going to be mirroring you exactly,” he says. So he added a “nice slow breathing rate” as a default setting.

So what does Tim’s sister think of the hug-bot? “She finds it very cute,” he says. She hasn’t tried it overnight yet. Tim’s friends have, though. “One of the things that kind of surprised me,” he says, “was how much the kids who use the device found it quite relaxing and reassuring in a way that wasn’t actually directly related to sleep.”

Tim believes his robots might help people in other settings, too.

Some people benefit from emotional support dogs, for example. But some places might not allow animals. In a super-clean hospital, an animal may pose a risk to sick kids. “Being able to reassure kids is quite a challenging thing,” Tim says. “But it would be cool if my product could do it.”

Regeneron ISEF is a program created and run by the Society of Science (which also publishes this magazine). Tim and Nichelle are among 1,657 students — from 62 nations or territories — competing at the 75th annual ISEF. These participants shared in nearly $9 million in prizes.