Integrated guidance and control for missile with narrow field-of-view strapdown seeker

Due to the removal of the mechanically stable platform in the conventional gimbaled seeker, the strapdown seeker's measurement is coupled with the missile body attitude motion, such that the inertial line-of-sight (LOS) angular rate required to implement traditional guidance laws cannot be measured, and the field-of-view (FOV) limit must be considered when designing guidance and control systems for a strapdown homing missile. To address these practical problems, an integrated guidance and control (IGC) scheme with considering the FOV limit is proposed in this paper. A novel IGC model is first derived based on the body-LOS (BLOS) angle that a strapdown seeker can directly measure, and then an IGC controller is designed using the dynamic surface control technique. A great merit of this design is that the inertial LOS angle and its angular rate are not needed, and thus the filters/estimators required to extract this guidance information in previous studies can be canceled. Next, by using the output to input saturation transformation (OIST) technique, the FOV limit, which is always considered as a state/output constraint, is transformed to a time-varying boundary limitation on the control input, and then is handled simultaneously with the actuator saturation constraint. Finally, extensive numerical simulations against both stationary and moving targets are performed to fully demonstrate the efficiency of the proposed IGC law.