Estimation of the Center of Mass: From Humanoid Robots to Human Beings

This paper presents a new technique for estimating the center of mass of articulated rigid body systems. This estimation technique uses the statically equivalent serial chain, a serial chain representation of any multilink branched chain whose end-effector locates directly the center of mass. This technique works based on a knowledge of only the kinematic architecture of the system and does not require the total mass, or any of the individual body´s mass or length properties. This constitutes an advance in center of mass estimation, providing an alternative to techniques requiring continuously a force plate. A comparison of these estimation techniques is presented. The modeling and estimation technique is then implemented on a human subject.