Scientists have created soft robots that jump under light

Jumping under infrared light

Researchers at North Carolina State University have created teardrop-shaped soft robots that bounce up or forward when exposed to infrared light. And they keep jumping while the light is on. The work demonstrates a new mechanism for self-resetting jumping behavior in soft robotics.

Simple twist design

“This 'ring jumper' design is very simple,” says Jie Yin, a professor of mechanical and aerospace engineering at NC State and author of a paper published in the Proceedings of the National Academy of Sciences. - We use torsion to accumulate elastic energy, and then release it all at once. And the design itself is such that it does not need a reset between jumps. It recharges itself."

The robots are made from a teardrop-shaped liquid crystal elastomer tape with a thin V-shaped aluminum tube at one end. When exposed to light from an infrared lamp, the surface of the tape contracts, causing it to rotate.

How energy is stored

The rigid V-shaped part at one end prevents the tape from simply rolling in place, causing it to curl tighter and tighter. This accumulates energy until the twisting reaches a critical point. Then the tape releases energy, the V-shaped end of the drop snaps down and hits the surface. This throws the drop into the air.

Having released the accumulated energy, the drop returns to its original shape. The process is repeated endlessly as long as the robot is under infrared light.

Motion control through geometry

“We found that we could control the movement pattern by making small changes to the design,” says Fangjie Qi, first author of the paper and a postdoctoral fellow at NC State. - If the V-shaped end of the drop is very wide, at an angle of 120 degrees, the robot simply crawls forward. If you reduce the angle to 90 degrees, it jumps forward. And if you lower it to 50 degrees, the robot makes a vertical jump. In other words, a single geometric parameter determines whether it will crawl, jump forward, or fly up.”

“We could also increase the jump distance by adding a small weight to the rounded end of the drop,” adds Qi. “This shifts the center of mass and provides a more powerful and stable forward movement, like a swimmer leaning forward when diving off the starting block.”

The role of light intensity

In addition, the researchers found that the intensity of infrared light plays an important role. “It needs to be strong enough to cause a jump, but not too strong, otherwise the robot starts jumping erratically and in unpredictable directions,” explains Qi.

During proof-of-concept testing, the researchers found that the teardrop-shaped robots could jump over slopes, obstacles, and a variety of surfaces: grass, sand, rocks, and mulch.

Application prospects

“There are no direct applications for this work yet, but it is a fundamental advance that is worth exploring for potential use in environmental navigation, swarm robotics, and rough terrain navigation,” Yin concludes.

Publication data

Fangjie Qi et al., “A self-resetting soft ring for autonomous continuous jumping in unstructured environments,” Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2607940123

Reference: Light-Up Soft Robots That Can Jump Infinitely (2026, August 28), retrieved August 29, 2026, from https://techxplore.com/news/2026-08-powered-soft-robots.html