Attitude/Orbit Engine Compound Control for Hypersonic Target Interceptor With Discrete-Time Inputs and State Constraints

This article proposes a strongly coupled integrated guidance and control (SCIGC) law for accurately intercepting the near-space hypersonic target under attitude/orbit engine compound control subjected to discrete-time inputs and multiple constraints. Based on the characteristics of attitude/orbit pulsed engine and full strapdown seeker, the discrete-time SCIGC model is constructed including control inputs coupling, guidance/control system coupling, field-of-view (FOV) constraint and impact angle constraint. The proposed control law adapted to the discrete-time inputs is presented by combining the high-order multi-dimensional sliding mode control (SMC) for utilizing the couplings, the prescribe performance function (PPF) for satisfying FOV constraint without ignoring the couplings and the extended disturbance observer (EDO) for estimating the mismatched unknown uncertainties. The stability of proposed control law-based closed-loop system is guaranteed. The effectiveness and robustness of proposed control law are illustrated by numerical simulations and Monte Carlo tests.