Meet Tumro, a jumping robot inspired by beetles

With its unique carbon fiber skeleton, this jumping robot closely mimics the energy-storing tissues found in insects.

Scientists have created a robot that may look familiar. Inspired by jumping beetles, like weevils and the common flea beetle, this robot can jump – a skill that its inventors say makes it particularly adept at navigating difficult terrain.

“Jumping beetles rely on their leg muscles to stretch the elastic tissue of their legs to store energy during jumping, a mechanism that makes their jumps extremely efficient,” said co-author Yanjie Wang from an article recently published in Advanced intelligent systems.

“In our work, we simulate this jumping mechanism with a robotic skeleton made of a composite material of carbon fiber and epoxy resin to act as an insect-like energy storage tissue.”

One robot, two modes of locomotion

Named Tumro, the prototype robot is 320mm long and roughly shaped like a spool. It has a long elastic skeleton with an independently driven 80mm diameter wheel at each end. Tumro can move in two different ways: crawling and jumping. When crawling, the robot’s low profile allows it to move in very small spaces; it can also overcome smaller obstacles.

When encountering an obstacle too large to overcome, the robot can be made to change posture, turning on one end while its elastic skeleton transforms from a coil shape to something resembling a Chinese lantern . This form stores the energy necessary to perform its second form of locomotion.

When the stored energy is released, the robot can jump up to 3 meters, or 40 times its own height. When the robot lands, it can quickly return to its original shape and resume exploring.

Wang said this capability gives it an advantage over single-motion robots. “The single-motion jumping robot has only one movement function: jumping. Even on a flat surface, it can only move by jumping, which will waste a lot of energy and reduce the practicality of the robot,” he said. “Multi-movement jumping can effectively integrate the movement of the wheels into jumping, which greatly improves its practicality and endurance.”

The prototype robot is not autonomous; it requires an operator to tell it when to jump, but because the angle of the jump is fixed, the operator knows exactly where it will land.

“In practice, we adjust the robot’s jumping direction based on the movement of the wheels,” Wang explained. “We plan to make the robot more intelligent in subsequent improvements so that it has the ability to overcome obstacles autonomously.”

Better jump, increased versatility

Tumro is not the world’s first jumping robot, but Wang said it is an improvement over existing designs in which the energy storage mechanism is added to the robot rather than being integrated to the structure itself.

“By integrating the robot skeleton with the energy storage mechanism, we can effectively improve the energy density of the robot during the jumping process,” he said.

Taher Saif, an engineering professor at Grainger College of Engineering in Urbana, Ill., who was not involved in the study, said the work appears to represent an important advance in the field of robotics.

“They achieved several things, one being a high jump relative to body size and stability,” he said. Giving a high-jumping robot the ability to land upright can be an ambitious goal for a design team, Saif said, because the robot doesn’t always fall in exactly the same way.

In their article, the authors wrote that a robot capable of crawling and jumping is more practical for working in places where the terrain is uneven and unpredictable. “The crawling and jumping robot shows promising potential for various applications, as it demonstrates the ability to navigate various road conditions using different modes of movement,” they wrote.

Wang also said a jumping robot could be a good tool for space exploration, especially on low-gravity worlds. “For future exoplanet exploration, low gravity will also greatly improve the robot’s jumping effect,” he said.

Saif said he would be interested to see future work demonstrating the scalability of the technology. “Can they go from small to large, and what are the consequences? he said.

He also noted that future robots could incorporate other types of biological movements to make them more agile. “I think in general the robotics community is trying to mimic more and more of the behavior of biological systems,” he said, “and this paper is a step in that direction.”

Reference: Yanjie Wang, et al., Tumro: an adjustable multimodal wheeled jumping robot Based on the bionic mechanism of jumping beetles,Advanced Intelligent Systems, (2024). DOI: 10.1002/aisy.202400024