Dynamic high gain scaling based output feedback for nonlinear systems with time-delayed input unmodeled dynamics

A general class of uncertain nonlinear systems with uncertain input unmodeled dynamics with time delays is considered. The system structure includes a core nominal subsystem of triangular structure with additive uncertain nonlinear functions, a coupled set of uncertain nonlinear appended dynamics, and uncertain dynamic input nonlinearities with time-varying uncertain time delays. The input unmodeled dynamics subsystem is coupled with the entire state of the system including the unmeasured state variables of the uncertain nonlinear appended dynamics coupled with the nominal triangular system and is also allowed to depend on the time delayed versions of the overall system state and control input signals. A globally stabilizing delay-independent robust adaptive dynamic output-feedback controller is designed based on the the dual controller/observer dynamic high-gain scaling with an additional dynamic scaling based on a singular-perturbation-like redesign to address the uncertain non-affine input perturbation and time-delayed input unmodeled dynamics.