Integrated design of guidance and control system considering body line-of-sight angle and input constraints

Compared with the traditional gimbal seeker, the coupling of guidance loop and control loop is more easily caused by the strapdown seeker, so the field-of-view (FOV) limit of the strapdown seeker is more easily violated. To solve this problem, an integrated guidance and control method considering the seeker's FOV constraints and input constraints is proposed. Firstly, the line-of-sight (LOS) decoupling principle of strapdown seeker was performed on the traditional integrated guidance and control (IGC) model to deal with the problem of FOV constraint, and then the actuator saturation was employed to build a nonlinear strict feedback state equation with unmatched uncertainties. Secondly, the dynamic surface control (DSC) based IGC law considering body line-of-sight angle (BOLS) and input constraints was designed with the extended state observer (ESO) to estimate and compensate the uncertainties. To deal with the FOV and input constraints, the barrier Lyapunov function and Nussbaum function were employed, respectively. Finally, The stability of the closed loop system was proved by using Lyapunov stability theory and numerical simulation verified the effectiveness of the proposed method.