Human Walking Isn’t All Hard Work, or

How to Freeload on Physics


Professor Art Kuo


Department of Mechanical Engineering

University of Michigan



It takes considerable effort in order to walk, both to control the motion and to provide energy. But just how much control is needed, and where does the energy go? To answer this question we might consider just how little control and energy are needed. Passive walking machines are two-legged mechanisms that can walk down a gentle slope with no control whatsoever and no external energy input. Their movements look surprisingly human, and in fact it appears that humans harness the passive dynamic properties of the limbs when they walk, just as the machines do. Humans need to exert some control, but make best use of physics to minimize their effort. We will use simple minimization principles to interpret theoretical and experimental evidence for freeloading on physics.




Friday, February 8, 2002

3:30 - 5:00 p.m.

1500 EECS