Robot fish can dive beneath water's surface

Robotics researchers in Singapore say their newest robot fish that mimics the movement of a carp could have a number of uses in marine environments. The robotic autonomous underwater vehicle could conduct underwater archaeology by exploring nooks and corners of wreckage or sunken cities, help lay undersea communication cable, or have a number of military applications, they said. Researchers at the National University of Singapore said their robot can be programmed to perform specific functions, and has total freedom of movement within an underwater environment. "Currently, robot fish capable of 2-D movements are common, meaning that these models are not able to dive [down] into the water," Xu Jianxin of the university's department of electrical and computer engineering said. "Our model is capable of 3-D movements as it can dive and float, using its fins like a real fish," he said in a university release Wednesday. "Compared to traditional AUVs, they are certainly more mobile, with greater maneuverability." The researchers spent 3 months studying the movements of carp. "We chose to study carp because most fish swim like them," Fan Lupeng said. "There is no literature at all on designing a mathematical model on the locomotion of fish and so we had to start from scratch. We used a camera to capture all the possible movements of a carp and then converted the data mathematically so that we could transfer the locomotion of real carp to our robot using different actuators." The researchers' prototype is about 5 feet in length, weighs about 22 pounds and can dive to a depth of 6 feet.