Towards the centipede robots

In the case of an advanced bipedal robot, many sensors are usually necessary for it to be able to maintain its balance in real time while moving over a terrain. Relying so heavily on sensors makes the robot vulnerable to sensor failure, something that can easily occur in harsh environments, such as a disaster scene or the surface of another world, and also in rapidly changing environments. With four, six or eight legs, the problem tends to be reduced. And with more legs?

Centipedes are known for their meandering gait. With tens or hundreds of legs, they can traverse any terrain without stopping.

A team including Baxi Chong, Daniel Goldman, Juntao He and Daniel Soto, all from Georgia Tech in the United States, developed a theory that adding pairs of legs to a robot increases its ability to move with speed. dexterity, speed and stability on difficult surfaces. This redundancy of legs makes them successful on their own without the need for sensors to interpret the environment. If one leg fails to properly brace itself on the ground, the abundance of legs keeps the robot moving and prevents it from falling over, no matter what. This makes such a robot a reliable system for traversing rugged terrain and even for moving a load from one site to another over difficult terrain.

Intrigued to see if a large number of limbs could be useful for locomotion in a robot, the team prepared difficult terrain and tested a robot on it by increasing its number of legs by two at a time, starting with 6 and eventually expanding to 16. As the number of legs increased, the robot could move more agilely across the terrain, even without sensors, as theory predicted. Finally, they tested the robot outdoors on real terrain, where it was able to navigate various environments.

Test robot centipede, with only six legs at the time of taking the picture. (Photo: Georgia Tech)

While bipedal and quadrupedal robots rely heavily on sensors to navigate complex terrain, the new multi-legged robot takes advantage of leg redundancy and can perform similar tasks to those robots and at a lower cost.

This makes centipede robots an ideal choice for applications in agriculture, space exploration, and even search and rescue.

The researchers are already applying their discoveries to agriculture. Goldman has co-founded a company that aims to use these robots to weed farmland where herbicides are ineffective. “They’re kind of a Roomba, but outdoors, for complex terrain,” Goldman explains.

These researchers have already completed two studies in this line of research and development. The first is titled “Self-Propulsion via Slipping: Frictional Swimming in Multilegged Locomotors” and was published in the Proceedings of the National Academy of Sciences (PNAS) academic journal in March. The second is entitled “Multilegged Matter Transport: A Framework for Locomotion on Noisy Landscapes” and has been published this May in the academic journal Science. (Fountain: NCYT by Amazings)