An innovative, snake-like robot can swim silently in salt water without an electric motor. The robot, developed by engineers and marine biologists at the University of California, uses artificial muscles filled with water to propel itself, the German News Agency reported.
The team, which includes researchers from UC San Diego and UC Berkeley, say the bot is an important step toward a future when soft robots can swim in the ocean alongside fish and invertebrate without disturbing or harming them. Today, most underwater vehicles designed to observe marine life are rigid and submarine-like and powered by electric motors with noisy propellers.
The Phys.org website cited Caleb Christianson, member of the study’s team, who said: “Instead of propellers, our robot uses soft artificial muscles to move like an eel underwater without making any sound.”
One key innovation was using the salt water in which the robot swims to help generate the electrical forces that propel it. The bot is equipped with cables that apply voltage to both the salt water surrounding it and to pouches of water inside of its artificial muscles. The robot's electronics then deliver negative charges in the water just outside of the robot and positive charges inside of the robot that activate the muscles. The electrical charges are used in boosting the bot’s muscles. The charges are located just outside the robot's surface and carry very little current so they are safe for nearby marine life.
Michael T. Tolley, another study team member, said: “Our biggest breakthrough was the idea of using the environment as part of our design. There will be more steps to creating an efficient, practical, untethered eel robot, but at this point we have proven that it is possible."