The octopus has inspired much technological innovation, and with good reason. This cephalopod is dexterous underwater, can camouflage itself, has well-developed vision, muscular arms, sensory suction cups and a soft body.
"The octopus is a fascinating animal, very special indeed, given its muscular structure that works like a modifiable skeleton," said Cecilia Laschi, a biorobotics professor at the Sant'Anna School of Advanced Studies in Pisa, Italy.
Laschi is currently editing a special issue of the journal Bioinspiration & Biomimetics, slated to be published this fall, about octopus-inspired robotics. [See photos of various octopus-inspired technologies]
Here are some novel technologies that researchers, like Laschi herself, have created based on the sea creature:
Octopuses have specialized cells that allow the animals to change the color and pattern of their skin, effectively camouflaging themselves from predators. A team of researchers led by Cunjiang Yu, an assistant professor of engineering at the University of Houston, and John Rogers, a professor of materials science and engineering at the University of Illinois at Urbana-Champaign, developed their own version of that camouflage.
The team's flexible camouflage system contains layers of heat-sensitive dye and light sensors. "We were part of an interdisciplinary team of researchers funded by the Office of Naval Research to look into the engineering science of how to reproduce the color-changing capabilities of cephalopods in manmade systems," Rogers told Live Science.
Last year, scientists from the U.S. Army Research Laboratory, the Edgewood Chemical Biological Center and the University of Maryland created 3D-printed self-sealing suction cups. These devices could help robots grasp objects, particularly in disaster relief environments that are too dangerous for humans to enter.
The researchers tested four fingertip-size prototype suction cups made from a type of polymer that solidifies under UV light. Results showed that the cups were strong enough to hold up a wine bottle, according to the U.S. Army Research Lab.
Harvard University scientists led by chemist George Whitesides created a soft, color-changing robot two years ago that was inspired by octopuses and squid.
The four-limbed robot has a separate layer of tiny channels through which liquid dyes can be pumped in and out. The color of the dyes can be combined to help the robot blend into its surroundings.
More recently, the team developed a new soft robot. While this one doesn’t change color, it has the same shape as the original and can move around autonomously. Made from silicone, hollow glass microspheres and specialized synthetic fabric, it is resilient enough to withstand flames, water and being run over by a car. The new journal Soft Robotics featured the robot design in the publication's first issue.
Last year, scientists from the Foundation for Research and Technology – Hellas in Greece tested an eight-armed robot prototype underwater. The machine not only looked like an octopus, but also mimicked that creature's movements. [Super-Intelligent Machines: 7 Robotic Futures]
The project's goal is to investigate new types of propulsion to make it easier and more efficient for robots to transport heavy loads underwater.
Experiments inside a water tank with the eight-arm robotic prototype successfully demonstrated an oar-like motion called sculling, and attained a speed of 0.2 body lengths per second according to the researchers' paper for the 2013 IEEE International Conference on Robotics and Automation.
The octopus's highly distributed body control prompted researchers from the University of Zurich, in Switzerland, and Kyoto University, in Japan, to create and study a sensor-laden silicone arm. The sensors detect the arm’s position as it rotates, allowing the researchers to track and analyze the dynamics at play.
Nonrigid materials are typically difficult to control, so the scientists hope their calculations will lead to more-intelligent soft-robot interfaces.
"Many living things have very soft bodies, and the octopus serves as the extreme case," said Kohei Nakajima, an assistant professor at Kyoto University in the Hakubi Center for Advanced Research, who is working on the arm. "This is why many researchers, especially from bioinspired robotics, are interested in it."
Wearable robotic arms
A recent prototype for wearable robotic arms may resemble the Spider Man supervillain Doctor Octopus but the device, created by a team from MIT’s d'Arbeloff Laboratory, was created with good intentions.
Giving people extra arms could one day help prevent injury for workers who perform repetitive, difficult tasks. The lab's conceptual images show these "supernumerary robotic limbs," or SRLs, mounted either on the shoulders or at the waist. In tests this summer, a shoulder-mounted prototype demonstrated how the arms can mimic the wearer's actual arm movements.
The PoseiDRONE is a spinoff from the European Octopus Integrating Project, which worked on novel design principles and tech for next-generation soft robots based on the behavior and characteristics of octopuses.
Cecilia Laschi and her colleagues are working to build a new robot made from up to 90 percent soft materials that can survive rough underwater conditions while doing risky work. The goal is for the PoseiDRONE robot to swim, crawl and manipulate tools underwater.
In the future, soft robots like this could perform such tasks as underwater maintenance on offshore wind turbines, or they could assist with oil-drilling operations. An updated prototype is being tested now.
Another European Octopus Project spinoff that Laschi and her team started is the STIFF-FLOP project focused on cognitive systems and robotics for surgical operations. The project aims to create a soft, flexible endoscope for minimally invasive surgery. So far, the design is drawing inspiration from elephant trunks and octopus arms.
Laschi said her lab used to keep live octopuses for measurements and observation to inform the endoscope and other projects. This helped the researchers better get to know the animals. "They are unexpectedly interactive with human beings," she said. "Impressively, all our animals showed pretty different behaviors and attitudes, one from another."