Octo-robot in the works

Israeli scientists are part of an international team working to build a robotic octopus that will revolutionize oceanic exploration.

octopus 88 (photo credit: )
octopus 88
(photo credit: )
Now building the world's first robotic octopus, and the world's first soft-bodied robot, Israeli scientists have joined a seven-group international team to help marine scientists explore nooks and crannies on the ocean floor, like an octopus would. Instead of dropping down clunky metallic submarines to the seafloor, which offer little in the way of precision, scientists are working on a soft-bodied robotic device that can gingerly walk over delicate objects, making sure not to damage coral reefs and pristine marine environments. The initial goal of the octopus robot is to monitor the effects of global warming on the sea. But Prof. Binyamin Hochner, from the Octopus Group of the Life Sciences Institute at Hebrew University of Jerusalem, imagines that when complete, the robot will also have applications in medicine - inside the body - and in search and rescue missions after devastating natural disasters, such as the recent earthquake in Italy. Funded by the European Agency's Framework 7, the international team - which includes scientists from the UK, Italy, Switzerland, Turkey and Greece - has been challenged to create the world's first soft-bodied robot sometime within the next four years. A robot of this type isn't as easy to build as some might think, but it offers many advantages over the stiff robotic arms now being used, says Hochner. "We just started on the new project with the European team, but now the idea is to build a robot, which is an entire octopus, for underwater exploring," says Hochner, who is working with Prof. Tamar Flash from the Weizmann Institute in Israel. The Israeli role in the project is in developing the mechanics of octopus locomotion. "We are collaborating with groups who are supposed to build the material, and from our side we are analyzing octopus behavior and motor control strategies for the arm, which have multiple degrees of freedom," explains Hochner. "The other groups are developing special materials to imitate the [octopus] muscle, and in my opinion this is the most difficult part of the project," he says. When complete, the scientists are expected to have built a life-like octopus robot, with a head, body and eight tentacles, each with a range of motion of 360 degrees. Elongating and stretching like the real ones do, the robotic tentacles will be able to stretch out and become thin in order to reach tiny objects in small spaces. Furthermore, the researchers intend to mimic the exact same structure and properties of a real octopus. There is something called intelligent design, where nature knows what's best, explains Hochner. "You shouldn't [build] only the arm, but [also] other parts of the biological system [of the octopus], which in nature also adapt to certain goals." Sucker systems, a nervous system, the sensory system and even the structure of the skin will be copied, he says. "We are replicating the muscular structure of an octopus by making a robot with no rigid structure - and that is completely new to robotics," said one of Hochner's partners from Italy. Octopus tentacles are made up of four longitudinal muscles, and the scientists plan on replicating them with a soft silicone rubber fitted with an electroactive polymer called a dielectric elastomer. When they apply an electric field to this polymer, it will squeeze the silicon making it shorter, and thereby mimic the contraction process in octopus and other soft-bodied marine animals. The Israeli group has been working on research and feasibility studies toward a robotic octopus for over 15 years. In the past, both the US Navy and the US Defense Advanced Research Agency (DARPA), funded Hochner to investigate the range, possibilities and limitations on flexible octopus arms. A study on how the international team plan to carry out the work has been published in the journal Biomimetics and Bioinspiration. So far, scientists have only been able to develop a snake-like tentacle that inflates with compressed air. Due to buoyancy issues, such a device would never work underwater. Hochner, who loves octopuses, is guardedly optimistic that the new team will be able to reach its goal. "It's a very fascinating animal," he says. "When we started to work on its motor control, we got very interested in its intelligence. It's considered to be the most intelligent invertebrate, and can learn and do things higher vertebrates can do," says Hochner, who compares the intelligence level to that of a rat or mouse. The original version of this article first appeared in Israel21c.