Current Interests

Walking and running gaits have traditionally been treated as distinct paradigms of movement. Walking is usually simplified to the motion of an inverted pendulum and running simplified as a spring mass. However, humans can walk and run with a single mechanical system, and neither robots nor human studies have yielded a single model that passively generates multiple gaits.

Our elastic locomotion model is made up of a point mass at the pelvis, two axially-compliant legs, and a torsion spring acting between the legs. After adding leg compliance to our simple model, we found that the motion of both legs for an entire step can be generated completely passively. A variety of human-like gaits may be produced with one simple model , without enforcing ground reaction force patterns or prescribing motions. Since no active control is used to generate these gaits, motions are produced simply by the interaction of leg stiffness, inertia, and gravity.