Adaptive tracking and disturbance rejection for uncertain nonlinear systems

This note addresses the problem of asymptotic tracking of arbitrary smooth bounded reference output signals, with simultaneous rejection of disturbances generated by an unknown linear exosystem. The problem is globally solved by output feedback for the class of nonlinear systems with output dependent nonlinearities and unknown linear parameters, under the assumptions that the system is minimum phase and the relative degree, an upper bound on the system order, the sign of the high-frequency gain are known.