Adaptive turbulence compensation for multivariable nonlinear aircraft models

In this paper, a multivariable adaptive disturbance rejection scheme is developed for solving the nonlinear aircraft turbulence compensation problem. A nominal design for output rejection of unmatched input disturbances is first constructed based on feedback linearization, for which the relative degree characterization of the control and disturbance system models is specified as a key design condition for turbulence compensation designs. Adaptive disturbance rejection control is then completed by deriving an error model in terms of parameter errors and tracking error, and constructing an adaptive law for updating the controller parameters. All closed-loop signals are guaranteed to be bounded and the plant output tracks a given reference output asymptotically despite the uncertainties of system and disturbance parameters. A nonlinear turbulence compensation design is studied for an aircraft system model, and simulation results from this benchmark aircraft model verify the desired system performance.