A View from David Zax
Robots on Wheels
And what a wheel! The inventive drive system enables a small robot to spin and turn on a dime.
Ever since those four horsemen, our culture has long been concerned with the locomotion of the apocalypse. IEEE Spectrum has spotted the more likely means of conveyance that will bring us the End of Days, however: a “singularity drive system” system that makes a robot whip around a room like a mouse on speed.
The wheel system is the brainchild of a surely well-meaning student at Bradley University, in Peoria, Illinois, named Curtis Boirum. He recently showed it off at RoboGames 2011. Here’s how the system works: the wheel is really half of a rubber ball that spins on its axis extremely quickly. By tilting the hemisphere ever so slightly, you can change the wheel’s direction, causing it to turn on a dime, if you want. You can see some of the acrobatics in the video here–from back when its creator called it a “hemispherical gimbaled wheel drive system” (he since changed the name to something much more suitably apocalyptic sounding).
It’s a neat design–and, in fact, an old one, as both Spectrum and a commenter on its Automaton blog point out. Back in 1938, Mechanics and Handicraft magazine had envisioned a similar device, crowing, “With a 600 h.p. airplane engine, this machine could travel at incredible speeds.” It appears not to have come to fruition though (have you seen any hemispherical gimbaled wheels affixed to any cars lately?), and Boirum has said he came upon the idea independently.
Indeed, it might be one of those ideas worth dusting off–it’s a cheap, simple, and powerful design, capable even of “delivering more torque than any of the poor robots that it’s attached to can reliably handle,” in the word’s of Automaton’s Evan Ackerman. Though it’s worth noting that a drive system like this only works optimally on a perfectly smooth floor. If the robotic uprising ever needs to go off-road, they might do better to stick to horseback after all.