Soft, fin-flapping robot explores the ocean’s greatest depths

By Mariusz Bogacki, Researcher and Science Communicator, Edinburgh

This is about to change, as the newest fish inspired deep-sea robot proves capable of reaching the deepest corners of the deepest known point in Earth's oceans.

Deep sea exploration is tricky. It requires heavily reinforced bulky vessels capable of withstanding huge amounts of water pressure. The Mariana Trench, the deepest part of earth’s oceans, bottoms out at about 11,000 meters below sea level. This is deeper than flipping Mount Everest upside down! The pressure at this point is about a thousand times the atmospheric pressure at sea level, translating to about 103 million pascals (or 15,000 pounds per square inch). Yet, microbial life seems to thrive even in these extreme conditions, feeding on algae, animal carcasses and other organic materials. It is these marine creatures that inspired the construction of a new snailfish-alike deep-sea robot.

Researchers at the Zheijiang University in Hangzhou, China, developed and successfully tested an untethered soft robot for deep sea exploration. The snailfish inspired robot is equipped with onboard power, control and actuation protected from pressure by integrating electronics in a silicone matrix. Following on the natural design of a snailfish, the electronics are distributed around its body in order to decrease the water pressure, while its elastic fins allow it to propel itself through the water.

The machine is still in its testing phase but the initial results are promising. Trials included allowing the robot to swim autonomously in a 70 meters deep lake and 3,224 meters deep South China Sea. The final test was conducted at a 10,900 meters depth of the Mariana Trench, where the elastic device was supervised with a deep-sea lander’s extendable arm which held the robot as it flapped its wings.

The robot is due to freely explore the undiscovered territories of the underwater world in the near future. Its development proves the potential of designing soft, lightweight devices for use in extreme conditions. We just need to come up with a catchier name to reflect its elastic powers!