A Guidance and Control Scheme Based on NDO for Flexible Hypersonic Vehicle

Abstract

AbstractA guidance and control scheme utilizing nonlinear disturbance observer (NDO) technique for flexible hypersonic vehicle (FHV) is designed in this article. The motion model of FHV in glide phase in denoted. The elastic states of FHV are regarded as uncertainties and the relevant items in the dynamical model of FHV are compensated by NDO technique. In the guidance sub-system, the command of angle of attack is generated based on sliding mode control (SMC) method. The low pass filter (LPF) theory and parametric command method (PCM) are introduced to calculate the change rate of command of pitch angle and the commands of fin deflections are obtained based on SMC approach in the attitude control sub-system. The effectiveness and robustness of the designed scheme are validated based on simulation experiments.KeywordsFlexible hypersonic vehicleGuidance and controlSliding mode controlNonlinear disturbance observer