Inspired by the human body, engineers have built a robotic fish from flexible silicone materials. The bot is powered by a blood-like fluid. The 40-centimeter (about 15.7 inch) mechanical, but soft robot is propelled by a dual-function fluid, which stores energy and moves the fish’s fins.

This robotic fish is a collaboration between engineers at Cornell University and the University of Pennsylvania. The design of the fish is similar to that of the lionfish. Robert Shepherd, the director of Cornell’s Organic Robotics Lab said the robot fish can fan its pectoral fins and swim more than 1.5 body lengths per minute, this is about 15 centimeters (about 6 inch) per minute. Shepherd said the swimming speed can be enhanced.

A school of fish poses for the camera. [File photo for creative use] IBTimes / Felipe Bascunan

The New Scientist said the robotic fish gets its energy from flow batteries. It consists of two electrodes and a liquid electrolyte that flows between them. “As the liquid moves around, it powers pumps present in the robot’s tail, dorsal and pectoral fins. Flow of the liquid also increases presure in certain areas. The mechanism is like inflating a balloon,” Sheperd explained. “It causes the shape and stiffness of parts of the robot to change. The fluid inflates one side of the robot fish’s tail and causes the other to compress.” Sheperd said this results in a bending motion.

For the robotic fish, the engineers used a battery fluid to move the fins. “This approach increased the amount of energy stored in the robot by 325% compared with a machine that has a separate battery and hydraulic-fluid system, said Shepherd.

They explained that robots require a lot of energy, which is why they are difficult to build and operate. Researchers said the latest creation could lead to increased energy density, autonomy, efficiency and multifunctionality in future robot designs.