Control for a class of nonlinear systems with uncertainties based on disturbance and state observer

A novel nonlinear robust control strategy for a class of uncertain nonlinear systems is presented, which is based on nonlinear disturbance and state observer technique, when internal unmodeled dynamics and external disturbances exist. The nonlinear disturbance and state observer is used to estimate the uncertainties, then its output is used to cancel the unknown term. finally, Aiming at the initial state deviate from stable limit cycle and anti-disturbance ability is an important issue in the research of biped walking robot, under the constraint of minimum energy consumption, Using this control method, the system status was converged to a stable limit cycle in a short time, and the anti-disturbance ability of the system is improved. The simulation results show the effectiveness of the algorithm proposed in this thesis.