A new robot octopus is able to swim through water in a manner similar to the wild animal.
Researchers from the Foundation for Research and Technology - Hellas in Greece developed the artificial animal. The device crawls, as well as swims in a manner much like the species that inspired the invention. Like its animal namesake, the robotic creature has eight tentacles, used for locomotion, as well as grasping onto objects.
The robotic swimmer utilizes flexible webbing, manufactured from silicon. An earlier webless version of the octobot was able to swim through water at just four inches per second. Addition of the pliable webbing increased the top velocity of the robot by 80 percent.
Researchers believe the webbing helps generate more force pushing back on water than arms alone could deliver. This greatly improves the efficency of energy to velocity, known as the cost of transport (CoT). Without the webbing, the CoT is just 0.62, but the flexible membrane increases that figure to 0.85.
The robotic octopus is able to carry items as it travels underwater, and the device has been successfully tested in the open Aegean Sea. A yellow ball was used during tests, which the octobot grasped between a pair of tentacles.
During tests, many fish followed the artificial octopus as it traveled through the water, a behavior researchers believe could be used in the study of marine wildlife.
"They suggest that the robot might therefore make a good platform with which to observe ocean life without disturbing it too much, as long as you're not trying to observe something that is often made a meal of by eight-armed cephalopods," IEEE researchers wrote in a press release announcing the invention.
The Octobot measures around 14 inches long, so top swimming speed of the new design is roughly equivalent to half a body length every second.
Aquatic robots are usually inspired by fish, but this new design, based on cephalopods, offers some advantages over other designs. Natural octopus use their tentacles to propel themselves through the water in a process called sculling.
Octopus in the wild often crawl along the seafloor, when they are not in a hurry to travel to their intended destination. The new robotic device is able to use this form of locomotion, in much the same manner as their natural counterparts.
A presentation about the Octobot was delivered at the IEEE/RSJ International Conference on Intelligent Robots and Systems, a four-day technology meeting held in Chicago, starting on Sept. 14.
Demonstration of the robotic octopus is shown in a new video from IEEE Spectrum available on their YouTube channel.
