David M. Patrick has accidentally re-invented the wheel. The California-based inventor was toying around with six short, curved lengths of cable that he had connected into a sort of helical loop--and then he accidentally dropped it. What he observed next was surprising: The loop began to roll... and roll... and roll. It was a self-balancing wheel.
Even stranger was that no one expected it to roll; Patrick's loop actually looks square when it is rolling. A lifelong skater, Patrick then prototyped a skateboard wheel based on his design, this one comprised of side-by-side helical coils. He call it the Shark Wheel:
Most interesting is that the Shark Wheel's contact patch—the portion of the wheels in contact with the ground at any given moment in its rotation—is so reduced that it cuts down on hydroplaning by channeling the liquid between the coils. Automotive tires are of course designed to do this, and in practice have varying degrees of efficacy.
Logic says that the reduced contact patch of a Shark Wheel would not be desirable in an automobile, where the goal is to maximize grip; but the helical nature of the Shark Wheel oddly provides lateral stability—at least in skateboard tests—due to its unusual shape. I'd be very interested to see if this could be adapted for automotive or motorcycle use.
At press time the Shark Wheel was 65% funded on Kickstarter, with over a month to go. Buy-in for a set of four starts at $45.