Generalization of proportional adaptation law for L1 adaptive controller

The paper presents a generalized framework for an L₁ adaptive state-feedback controller with proportional adaptation gain. Using the decoupling property for estimation and control loops of the L₁ adaptive controller, we show that this generalized architecture has the potential of unifying several nonlinear control methods in a single framework. In all cases, the proposed controller, similar to other L₁ controllers, offers systematic tuning of robustness and performance bounds, by increasing the adaptation gain and careful selection of the lowpass filter. Simulations verify the theoretical findings.