Conservation of Angular Momentum During Human Loco- motion

Motivation: The mechanics of walking and running are extremely complicated, exemplified by the fact that no robots can perform robust human walking. By focusing on angular momentum, a fundamental physical concept, we hope to develop a relatively simple model of stable motion. The angular momentum of a system is conserved if no external torques act on the system. During the aerial phase of locomotion, angular momentum is obviously conserved, but the interaction of the feet with the ground introduces external torques on the body. Therefore, there is no a priori reason for angular momentum in the CM frame to be conserved. However, recent observations in our research indicate that angular momentum is conserved to a large extent.