Optimal predictive guidance law based on guidance law identification using variable structure interactive multiple guidance law model

For a defender protecting a target from an incoming high-maneuvering homing missile, an Optimal Predictive Guidance Law (OPGL) is proposed based on a guidance law identification algorithm. First, a guidance law identification algorithm based on the Interactive Multiple Guidance law Model (IMGM) is designed. IMGM uses multiple sub-filters for parallel processing, and there is interaction between the inputs and outputs of the sub-filters. Second, the VSIMGM algorithm is further designed based on the IMGM algorithm. In this algorithm, a new guidance law model subset is constructed based on the original guidance law model set. By reducing the number of models, the model error is reduced, and the identification probability of the guidance law model is improved. Then, based on the identification result of the identification algorithm, the OPGL is given by using the variational method through the steps of linearizing the kinematic model and reducing the order of state equation. The OPGL reduces the overload requirement of the defender and improves interception accuracy without assuming the maneuver mode of a homing missile. Finally, the effectiveness of the proposed OPGL and guidance law identification algorithm based on VSIMGM is demonstrated using numerical simulation. Compared with the guidance law identification algorithm based on MMAE and IMGM, the guidance law identification algorithm based on VSIMGM can quickly, stably, and accurately identify the guidance law. In addition, based on the guidance law identification results of the homing missile, compared with proportional navigation, augmented proportional navigation, differential game guidance (DGG), and sliding mode guidance (SMG), OPGL can reduce the required overload of the missile and achieve accurate interception.