Feedforward control of flexible hypersonic vehicle based on multi-modal optimal input shaper

Firstly, this paper proposes an aeroelastic feedforward suppression strategy for hypersonic vehicle based on multi-modal optimal input shaper. The objective function is constructed separately for the first two elastic modes to minimize elastic vibration, and the corresponding optimal input shapers are determined and convolved to generate a multimode optimal input shaper. A gradient algorithm with integral cost and robustness modifications is employed to estimate the natural oscillation frequency of the first-order elastic mode of the hypersonic vehicle (HSV). Subsequently, an optimal input shaper is constructed based on this determination. A simplified controller design approach is adopted using Jacobian linearization and tensor product transformation to establish a polytopic linear parameter varying model that accounts for parameter uncertainties. Then, a tube-model predictive control (Tube-MPC) strategy is designed, ensuring stable tracking of the hypersonic vehicle with respect to the reference commands. Simulation experiments are conducted to validate the effectiveness of the proposed method.