New research results are the first to explain the physics and mathematics of hula hooping.<\/p>\n
Hula hooping is so commonplace that we may overlook some interesting questions it raises: “What keeps a hula hoop up against gravity<\/a>?” and “Are some body types better for hula hooping than others?”<\/p>\n A team of mathematicians explored and answered these questions with findings that also point to new ways to better harness energy and improve robotic positioners.<\/p>\n “We were specifically interested in what kinds of body motions and shapes could successfully hold the hoop up and what physical requirements and restrictions are involved,” explains Leif Ristroph, an associate professor at New York University’s Courant Institute of Mathematical 糖心视频s and the senior author of the paper, which appears in the Proceedings of the National Academy of 糖心视频s<\/em><\/a>.<\/p>\n To answer these questions, the researchers replicated, in miniature, hula hooping in NYU’s Applied Mathematics Laboratory. They tested different shapes and motions in a series of experiments on robotic hula hoopers using 3D-printed bodies of different shapes (e.g., cylinders, cones, hourglass shapes) to represent human forms at one-tenth the size.<\/p>\n These shapes were driven to gyrate by a motor, replicating the motions we take when hula hooping. Hoops approximately 6 inches in diameter were launched on these bodies, with high-speed video capturing the movements.<\/p>\n