Error shaping strategy-based multi-constrained integrated guidance and control for hypersonic vehicle in dive phase

In this paper, a novel integrated guidance and control (IGC) method is presented for a hypersonic vehicle in dive phase considering multi-constraints, input saturation, and complex uncertainties (such as model uncertainty and external disturbance). The first challenging problem is the severe saturation of angle of attack (AOA), which is caused by the terminal impact angle constraints in the guidance loop and may lead to the failure of the mission. Focus on this, this paper presents a novel perspective to predesign the practical AOA saturation-alleviation convergence characteristic of the line-of-signt (LOS) angle errors by leading the LOS angle errors converging along the range-based prescribed performance functions, which is called error shaping strategy. Then, considering the precise attitude control problem under state constraints, input saturation, and lumped uncertainties in the control loop, a composite adaptive attitude control scheme is constructed. In this scheme, the asymmetric time-varying barrier Lyapunov function is introduced to ensure state constraints with relaxed tracking error restrictions. On this basis, the recurrent cerebellar model articulation controller neural network and anti-saturation auxiliary system are designed to deal with the lumped uncertainties and saturation error, respectively. The stability of the closed-loop IGC system is proved by the Lyapunov stability theory. Finally, numerical simulations are carried out to show the effectiveness and robustness of the proposed IGC method.