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Robot Octopus Takes to the Sea

Watch this cephalopod robot swimming happily in the Aegean Sea

2 min read
Robot Octopus Takes to the Sea
Image: FORTH

Early last year, we wrote up some betentacled research from Greece that explored what gaits were most effective at propelling a robotic octopus through water. The researchers commented that they were working on adding another physical feature flaunted by the biological version of the octopus: a web between their tentacles, which they hypothesized might help swimming speed or efficiency. Now the researchers report that the addition of a soft and supple silicone web has nearly doubled the speed of the roboctopus, and not satisfied with that, the scientists have also taught it to crawl, carry objects, and swim free in the Aegean Sea.

The video below has four parts to it: the first shows the difference between the robotic octopus swimming with just flexible arms, and swimming with just flexible arms in addition to a web. The most obvious difference is the speed: just over 100 millimeters per second with arms only, and up to 180 mm/s (or 0.5 body lengths per second) with the web. This is a significant increase, obviously, but what's more important is the overall cost of transport (CoT), which is a measure of the efficiency of the robot (specifically, the ratio of the energy put in over the resulting speed). The CoT for the arms-only version is 0.85, whereas the web drops that down to 0.62. So yeah, having that web in there is better in almost every way.

Also in the video below are three other clips that aren't related to the paper but that we thought were pretty cool. The first clip shows the robot octopus crawling along the ground, which is a very typical gait for most real octopi who aren't in a hurry, to which yours truly can attest, as he has had many different species of octopus flee from him. The second clip has the robot octopus swimming along while carrying an object (note the yellow ball held by two tentacles), because just like a real octopus, it can do that. And the third clip shows the robot octopus swimming happily out at sea, completely self contained, in the Aegean. It's very relaxing, and remarkably realistic:

With the ocean swimming vids, the researchers pointed out to us that there are a bunch of little fish following the robot octopus around quite happily. 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. 

"Multi-arm Robotic Swimming With Octopus-Inspired Compliant Web," by Michael Sfakiotakis, Asimina Kazakidi, Avgousta Chatzidaki, Theodoros Evdaimon, and Dimitris P. Tsakiris from the Foundation for Research and Technology-Hellas (FORTH) in Greece, was presented last week at the IEEE International Conference on Intelligent Robots and Systems (IROS) 2014 in Chicago.

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Engineers battle the limits of deep learning for battlefield bots

11 min read
Robot with threads near a fallen branch

RoMan, the Army Research Laboratory's robotic manipulator, considers the best way to grasp and move a tree branch at the Adelphi Laboratory Center, in Maryland.

Evan Ackerman
LightGreen

“I should probably not be standing this close," I think to myself, as the robot slowly approaches a large tree branch on the floor in front of me. It's not the size of the branch that makes me nervous—it's that the robot is operating autonomously, and that while I know what it's supposed to do, I'm not entirely sure what it will do. If everything works the way the roboticists at the U.S. Army Research Laboratory (ARL) in Adelphi, Md., expect, the robot will identify the branch, grasp it, and drag it out of the way. These folks know what they're doing, but I've spent enough time around robots that I take a small step backwards anyway.

This article is part of our special report on AI, “The Great AI Reckoning.”

The robot, named RoMan, for Robotic Manipulator, is about the size of a large lawn mower, with a tracked base that helps it handle most kinds of terrain. At the front, it has a squat torso equipped with cameras and depth sensors, as well as a pair of arms that were harvested from a prototype disaster-response robot originally developed at NASA's Jet Propulsion Laboratory for a DARPA robotics competition. RoMan's job today is roadway clearing, a multistep task that ARL wants the robot to complete as autonomously as possible. Instead of instructing the robot to grasp specific objects in specific ways and move them to specific places, the operators tell RoMan to "go clear a path." It's then up to the robot to make all the decisions necessary to achieve that objective.

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