Constant pelvis height ZMP-based walking: A study on energy consumption during walking

Researchers introduced a constant center of mass walking, mainly to solve the ZMP equations analytically for center of mass trajectories in the x and y directions (case 1). In this paper, case 2 proposes that if pelvis is made constant instead, energy usage could be reduced particularly at the leg joints. CoM-based kinematics methods are used to realize each case. Walking simulations of 0.22km/h are utilized for observations. In the simulation results, case 2 consumed almost 12% less in total energy consumption (electrical and mechanical) compared to case 1.