Researchers study octopus flexibility to improve search-and-rescue robots

Roboticists seeking machines that can reach survivors in collapsed structures are examining the natural abilities of octopuses, which can compress their soft bodies to pass through very small gaps.

Wenci Xin, a researcher at the Singapore-MIT Alliance for Research and Technology, explained that conventional four-legged and wheeled robots, as well as snake-like designs, often lack the capacity to carry essential supplies while fitting into narrow spaces.

Together with biologist Tamar Gutnick of the Vienna Zoo, Xin’s team conducted experiments at a public aquarium in Vienna, offering octopuses holes of varying diameters cut into a clear acrylic panel. Video analysis showed that the animals first extended a single arm to probe the opening, then typically moved three to five arms through before pulling the rest of the body. When the aperture was larger than the distance between the octopus’s eyes, Mayan octopuses did not attempt entry, whereas common octopuses inserted all eight arms and compressed their body cavity and internal organs to squeeze through.

Gutnick noted that the octopuses appear to gauge the size of the opening before deciding to proceed. Xin said the goal is to translate this pulling behavior into a robot capable of navigating spaces that are otherwise inaccessible.

Engineer Mishu Duduta of the University of Connecticut, who builds bio-inspired robots, said the findings support a design approach that emphasizes pulling rather than pushing, potentially expanding the range of tasks robots can perform in disaster zones and other challenging environments.