When we think of a robot, we usually imagine it rigid with lots of joints and moving (never better said) robotic. However, in addition to rigid robots, there are also flexible robots, which mimic biological functions to meet your needs, for example sweating. A new model has been developed to improve its speed, it does so by mimicking the fastest animal of all, the cheetah.
Developed by North Carolina State University, the little robot uses a new technique where it changes its “spine” between a concave and convex shape. A movement similar to that of cheetahs when running and this allows them to reach speeds of 94 km / h on average. The little robot doesn’t go that far, but it improves significantly over other modes of movement like this centipede robot.
The LEAP (Leveraging Elastic Instabilities for Amplified Performance) spine developed in this experiment takes advantage of the flexible capabilities of the robot to improve its movements. They indicate that the fastest flexible robots to date could achieve speeds of 0.8 their length per second. In other words, if the robot measured 10cm in one second, it moved a distance of 8cm. With the new technique, they get a displacement per second of 2.7 times the length of the robot. Again, if the robot is 10cm tall, it moves 27cm in one second.
To achieve this curvature of the robot’s spine, it is has a rocker structure, as its creators call it. This means that it can only be kept stable and at rest in two positions (one concave and the other convex). By pumping pressurized air through the silicone channels of the column, they generate movement that changes the structure from one state (concave) to another (convex) and vice versa. This is how they make the robot jump and “gallop” like a cheetah.
The two positions of the bistable column. Via NCSU.
In the video, you can see how when the front feet touch the ground, the rear feet “jump” due to the arch of the spine. Then it happens the other way around, the spine takes on a convex shape so that the front feet extend out and reach a larger stride. Fundamentally galloping movement a lot of animals.
This movement appears to be also effective when climbing hills. By having less friction with the surface and by performing small “jumps”, the LEAP robot manages to climb slopes which, with other techniques, were not possible. Finally, this structure too can be used underwater to make the robot swim by imitating the wavy movement of the fish, as you can see in the research video.
While other rigid robots rely on locomotion techniques such as wheels or strong legs, this new technique launches an alternative for flexible robots, which are generally much slower. The question now is how the Boston Dynamics Spot would improve their acrobatic skills with a flexible spine like this.