Researchers at The University of Buffalo and Harvard University are now studying the movements of Stingrays, and how their movements can be replicated to produce more fuel efficient and agile unmanned underwater vehicles. Innovations of this magnitude would allow marine biologists and other scientists a chance to better study the depths of the ocean, and creatures living the depths we haven't explored thus far. Unmanned underwater vehicles of this nature could also assist crews in cleaning as well as rescue efforts beyond the shore.
Why the stingray? While other fish have a typical system of swimming, in that most wag their tails to swim forward and guide underwater, stingrays have a unique way of swimming, "like a flag in the wind," as quoted in the Phys.org article, "Stingray Movement Could Inspire the Next Generation of Submarines".
The researchers used fluid dynamics to map the flow of water and vortices around live stingrays while in motion. It is believed this is the first time the leading-edge vortex, the vortex at the front of a moving object, has been studied in underwater movement. It has been observed in the flight of birds and insects, and remains an important component of thrust in insect flight.
The observed vortices on the waves of the stingray's body cause favorable pressure fields which push the ray forward (low pressure in the front and high pressure on the back act as thrust for the stingray). Understanding vortices and their effect on movement in air and water can potentially lead to greater innovations down the road for cars, planes, and submarines.