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Generally, robots are initially designed via computer-aided software to obtain their parameters. However, the given parameters are not entirely true due to their unmodeled parts; therefore, system identification is needed, and physical conditions are crucial to guarantee feasible solutions. This study uses a quadratic programming regression model accompanied by physical consistency constraints and designs specific exciting motions for humanoid robots. The proposed constraints are designed based on the geometric approximation of link objects, the physically reasonable mass and inertia and the total mass of the robot being correct. The proposed exciting motions include the general walking motion and the single-leg support motion, which enable a more flexible and stable way to cause excitation in the floating-base system. The identified parameters are evaluated on the humanoid robot NINO. Furthermore, the error between the feedback information of the zero moment point and the command information of the center of mass are used for evaluating the identified dynamic parameters. According to the experiments with the proposed exciting motions, the identified parameters are found to be obviously better than the original computer-aided design parameters, especially in the x direction. [ABSTRACT FROM AUTHOR]

In this paper, a proposed momentum control framework adopts the quadratic programming method to handle the multi-task prioritized problem by assigning suitable constraints and the objective function, including desired end-effectors motions, the limitations of joints and the rate of change of linear and angular momentum of a robot. First, the centroidal momentum matrix is used to derive the relationship between the linear and angular momentum of the center of mass and the whole-body motion of the robot. Second, the linear quadratic state incremental walking pattern generator is used to regulate the rate of change of linear momentum of the robot for balanced walking. Then, according to the difference between the centroidal moment pivot and the zero moment point (ZMP), the compensatory rate of change of horizontal angular momentum can be calculated to keep the balance from unexpected larger disturbances. Finally, the performance of this control framework is verified effectively through the simulations and the experiments. In addition, the ZMP tracking performance is improved up to 50% in the simulations and 14% in the experiments. [ABSTRACT FROM AUTHOR]