Stingray-inspired robot cracks the mystery of how rays swim

'Nature seems to have already solved the problem.' Breakthroughs, discoveries, and DIY tips sent six days a week. To help figure out what makes stingrays such unique and unusual swimmers, a team of mechanical engineers at the University of California, Riverside (UCR) created a wavy robotic fin. After submerging the robot in underwater tunnels designed to mimic swimming near the sea floor, their tests indicate that different types of ray species may have evolved alternative swimming techniques that best suit their setting. Specifically, the findings suggest that some ray species swimming near the seafloor adjust the way their fins move and tilt to counter a downward force that would otherwise pull them toward the ground. It turns out that stingrays gracefully gliding along waves near seabeds aren't doing it to look cool.