An improved method of control law design at high angle of attack based on wind tunnel test data

This paper presents an improved dynamic inversion (DI) based method, which is further successfully applied to the high angle of attack flight control of the aircraft under the influence of unsteady aerodynamics. On the basis of large oscillation wind tunnel test data, the accurate unsteady aerodynamic model is established by the sequential minimal optimization - support vector regression (SMO-SVR) method. The nonlinear longitudinal aircraft model is created by considering engine model, atmospheric model, actuator model, and so on. In order to solve the problem of large control error and control delay caused by the unsteady aerodynamics, the improved DI method is proposed. The integral is added in the pitch angle rate control, and the control law of angle of attack is designed combining lag correction. The daisy chain allocation method is utilized to obtain the deflections of the control surfaces and the engine vector nozzle. Numerical simulation of Cobra maneuver is employed to demonstrate the advantages and potential practical application of the proposed improved control law design method.