Adaptive nonlinear generalized predictive control for hypersonic vehicle with unknown parameters and control constraints

In this article, an adaptive nonlinear generalized predictive controller is developed for the hypersonic vehicle with unknown parameter uncertainties and control surface constraints. A nominal controller based on generalized predictive control is first developed for the nominal longitudinal model. Considering the complicated practical flying environment and outer unknown disturbances, a parametric longitudinal dynamics model of the hypersonic vehicle is constructed. Then, an adaptive parameter estimation method is proposed to update the unknown controller parameters and parameter projection is applied to solve the control singularity and the parameter boundedness problem. Control surface is restricted to deflect in a range. To satisfy the above constraint, the predictive time should be selected appropriately. Through a large number of simulation experiments, the suitable ranges of the predictive time under different commands are given. All closed-loop signals are guaranteed to be bounded. And simulation results verify the effectiveness of the proposed controller.