Output Feedback Control of an Uncertain System using an Adaptive Observer

A method of adaptive output feedback control design for an uncertain nonlinear system is presented. The control design augments a state observer based linear control law by an adaptive observer in a manner that adaptive estimation and control augmentation is achieved through a single neural network. In this process, we show how the unmatched uncertainty is tackled by an adaptive signal. The proposed synthesis can be applied to non-affine systems having parametric and dynamic uncertainties. The approach is also applicable to non-minimum phase systems if the non-minimum phase zero dynamics are considered in the linear control design. We illustrate the effectiveness of the approach using an inverted pendulum example.