Imagine experiencing the upside-down thrills and G forces of a 100-meter-high roller coaster, but without tracks and within a space only seven meters high. That’s the idea behind Robocoaster, a programmable robot arm that can carry two passengers through loop-the-loops and barrel rolls at accelerations of almost twice the force of gravity. The ride, developed by Robocoaster of Warwick, England, and Kuka Roboter in Augsburg, Germany, is a modified cousin of the giant robot arms that handle everything from heavy lifting to spot-welding on automotive-factory floors. “Riders can choose from five levels: gentle, fun, fast, turbo, and extreme,” says Robocoaster president Gino De-Gol. That versatility makes the ride exciting for teens but still accessible to small children and senior citizens. Robocoasters are being tested at three amusement centers in the United States, Brazil, and Denmark, and could show up next year at major theme parks, says De-Gol.