Abstract:

Aiming at the coupling problem of the line-of-sight (LOS) measurement and missile attitude caused by the connection of the strap-down seeker and the missile body, a novel integrated guidance and control (IGC) method considering the field-of-view (FOV) angle constraint of the strap-down seeker is proposed based on the disturbance observer and the dynamic surface control theory. Firstly, the strict feedback state equation for the IGC design with FOV angle constraint is built. Secondly, a nonlinear disturbance observer is designed to estimate the model uncertainties which include the target maneuvering and the aerodynamic parameter disturbance, and the square of the estimation results are employed to the IGC design. Thirdly, the FOV constraint issue is handled based on the integral barrier Lyapunov function and the dynamic surface control, and the proof of the stability of the closed system and the uniform ultimately boundedness of the signals is also carried out using the Lyapunov theorem. The simulation results imply that the proposed IGC law can not only ensure the interception accuracy, but also satisfy the FOV angle constraint in the presence of different target maneuvering and the aerodynamic parameter disturbance.

Key words:  State constraint, Disturbance observer, Integrated guidance and control, Strap-down