That’s Hemispherical Omnidirectional Gimbaled wheel. As an idea it’s at least as old as 1938, but it’s lately been re-discovered by Curtis Boirum, an MS Mechanical Engineering student at Bradley University in Peoria, IL. The wheel is essentially a rubber hemispherical top spinning at very high speed and mounted on a gimbal. When the spinning axis is straight up, the wheel exerts negligible torque; but tilting it even slightly allows rapid torque development in any plane direction. The remarkably nimble vehicle in the video is essentially a trike with two free-spinning conventional wheels and one HOG wheel. Look at it go! Can’t wait to see what hobby roboticists, inventors, and entrepreneurs do with this. [via Hack a Day]