Narrator:       This is Science Today. As the saying goes, "It's as easy as riding a bike," but engineers at the University of California, Davis, are finding that understanding just how a human controls a bicycle is not so easy. In fact, Mont Hubbard, a professor of mechanical and aerospace engineering, says what makes riding a bike unique is that one uses all the sensory information available.

Hubbard:       We're sensing an awful lot of things — we're sensing using the inner ear, we have our visual system that provides a lot of information and then we're closing a feedback loop to do the right thing to keep the bicycle from falling over.

Narrator:       Hubbard and his colleagues hope that their research could lead to a new understanding of how humans interact with control systems, and new bicycle designs.

Hubbard:       How you would design a bicycle for a certain person, perhaps, or for a certain population of individuals like old folks or kids or young adult athletes, and how they should be different to make those different populations feel comfortable.

Narrator:       For Science Today, I'm Larissa Branin.