Sharks' Scales Create Tiny Whirlpools for Speedy Swimming
Sharks are noted for speedily cutting through water. Scientists have been focusing on how the sharks' denticles might boost swimming hustle and agility. The sharks' rough skin was thought to behave like the dimples on a golf ball , upsetting the flow of water over the surface to reduce the drag it experiences.
However, existing research into the benefits of shark husk bothered Lauder, since much of it was based on shark skin mimics that were held rigidly in place and laid triplex like a sheet of paper. "I have wanted to study the function of shark skin when it moves," he said. [ A Gallery of Uproarious Sharks ]
Shark robot
Lauder and Oeffner procured skin from several large mako sharks at a fish trade in in Boston and glued them onto a rigid piece of aluminum foil. They immersed this foil in a water tank, wiggled it from side to side with a robotic device to make it "swim," and flowed water against it to give it a push. By timing the water overflowing needed for the flapping device to essentially stay in place, they could determine how fast the robot was effectively swimming.
