This shape-shifting robot adjusts its body to walk across all kinds of terrain


Imagine running on a cement path, then suddenly on dry sand. Just to stay upright you will have to slow down and change the way you run. Likewise, a walking robot would need to change gait to manipulate different surfaces.

Usually we humans and most robots can only change How? ‘Or’ What we will run. But what if we could also change our body shape to run as fast and safely as possible on any surface?

We would like to rely on robots for difficult and dangerous tasks, from inspecting broken nuclear reactors to space exploration. For these tasks, a static body could limit the adaptability of the robot. A shapeshifting body could be the difference between success and failure in these unexpected environments. Better yet, a shape-changing robot could learn the best body shape for different environments and adapt to new environments as it encounters them.

In collaboration with the University of Oslo, we have successfully tested this idea with a four-legged robot that adapts its body to walk on new surfaces as it sees them, performing better than a static body robot. Our research is published in Nature Machine Intelligence.

A quadruped that changes shape

DyRET, the dynamic robot for embedded testing, or “the animal” in Norwegian from its creator, Tønnes Nygaard, was designed to explore the idea of ​​a shape-changing robot. Each of DyRET’s four feet has two telescoping sections, so he can change the length of his thigh or shins. The adjustments are made by motors integrated in the legs and the lengths can be changed automatically while the robot is running.

Motors can change the height of DyRET by approximately 20%, from 60cm to 73cm in height. These 13 cms make a dramatic difference in the robot’s walking. With short legs, DyRET is stable but slow, with a low center of gravity. In its highest mode, DyRET is more unstable when walking but its stride is much longer, which allows it to travel faster and overcome obstacles.