There are plenty of robotic submarines out there, from the Sawfish underwater lumberjack to such deep-diving explorers as the deep-sea Zeus II. Although these machines make it possible for humans to explore such fishy realms from a safe distance, they lack the finesse of good old Mother Nature.
On one hand, you have creatures such as the octopus, which can ghost across fragile coral landscapes and squeeze itself through the tightest of spaces. And then, in humanity's corner, you have enormous bulky subs with small, cumbersome arms.
Researchers from Greece, Italy, Israel, Switzerland, Turkey and the United Kingdom have proposed a compromise: soft, robotic tentacles. Cleverly dubbed the roboctopus by the likes of New Scientist magazine, the resulting underwater robot would be able to dance its way into delicate environments without disrupting or damaging the surroundings. While there's nothing inherently green about biomimicry (you could, in theory, build a robot crab programmed to eat hybrid cars), the roboctopus would allow scientists to better hunt for signs of climate change in narrow ocean floor cracks and amid fragile coral.
Every soft tentacle would contain four cords, each containing electroactive polymers that contract when hit with an electric field, causing the tentacle to flex this way or that. Developers are still working up to producing an actual prototype, but it could represent the ultimate in less invasive seafloor exploration.