An estimation based robust tracking controller design for uncertainnonlinear systems

摘要

We study the use of the equivalent control based disturbanceestimation idea in robust control design problems. For matcheddisturbances, the estimated parts can directly be eliminated by acancellation term in the control so that the system only needs to berobustified against residual estimation errors. For mismatcheddisturbances, the design method is presented on a tracking problem of anonlinear system in strict feedback form by directly incorporating theestimated disturbances into the backstepping control design. A nonlineardamping technique is used to deal with the controllable estimationerrors. A semi-global ultimate boundedness result is obtained fortracking error by a Lyapunov synthesis