Abstract:

 A robust backstepping control method based on the novel tracking differentiator is proposed, considering the air-breathing hypersonic vehicle model with parameter perturbations and external disturbances. The tracking differentiator is designed by using the tangent sigmoid function and the terminal attractor function. The parameters tuning rules are obtained through the frequency test, and the contrast simulation experiment is conducted. On this basis, a nonlinear disturbance observer is constructed to estimate the uncertainties of the model, thus enhancing the robustness of the controller. Also, the designed tracking differentiator is used to filter the virtual control variables, thus avoiding the problem of “explosion of term” in the traditional backstepping control. Finally, the effectiveness of the designed controller is verified by simulation.

Key words:  Hypersonic vehicle, Tracking differentiator, Disturbance observer, Backstepping control, Robust control