L1 Adaptive Output Feedback Controller to Systems of Unknown Dimension

This paper presents an extension of the L₁ adaptive output feedback controller to systems of unknown dimension in the presence of unmodeled dynamics and time- varying uncertainties. The adaptive output feedback controller ensures uniformly bounded transient and asymptotic tracking for system´s both signals, input and output, simultaneously. The performance bounds can be systematically improved by increasing the adaptation rate. Simulations of an unstable non-minimum phase system verify the theoretical findings.