Bicycle balance
While riding a bicycle, the rider balances and steers through feedback from (along with sight) the motion sensors in the inner ear. There are in fact three separate motion sensors: one tracks side-to-side balance, one front-and-back, and one for spin. The front-to-back balance is most sensitive, because that’s the one used to keep you from falling on your face while walking. However, front-to-back is irrelevant on a bike, because you face forward, and the wheels maintain front-to-back balance, and you must use side-to-side balance for control. If you’d like to control using the best receptors, there are two choices. One is to put the wheels side to side, and use the fine front-back receptors for speed control, like the Segway does. Another is ride sideways. In other transportation modes with a choice, this is usual. Eg., you can face front or sideways on a surfboard, but it’s much easier to balance facing sideways, with the best receptors aligned with the difficult axis. On snow, skiing use side-to-side receptors for turning, whereas snowboarding uses front-to-back receptors, and which sport carves better turns?
So, why not a bicycle which is ridden sideways? All good ideas have usually been done, and this is no exception. Photos, both geeky and nongeeky, below the fold:
Geeky:
SidewaysBike
Not geeky:
Dirt Surfer
What I find impressive about the Dirt Surfer is what they leave off. No steering control: bikes mostly steer by leaning anyway, so with a little bit of trail to ensure that the front wheel stays aligned with the direction of travel, you don’t need handlebars. No power: you either walk or take a lift to the top of a hill, attach a kite (seems natural enough for extreme sports freaks), or an electric motor. Later versions do have brakes, if you can grab the handle while crouching, but you can also just jump off or wait for the bottom of the hill, like skiing. Looks like fun.