Guidance And Control System Design Of Over-The-Shoulder Air-To-Air Missile

Over-The-Shoulder (OTS) launch technology as a new fire control means is getting more and more attention from various countries. This paper studies the guidance and control system design of OTS Bank-To-Turn (BTT) Air-to-Air missile (AAM). The study mainly includes turn laws optimization analysis and design, attitude control system design, and proportional navigation law analysis of BTT missile。Firstly, the mathematical model of BTT AAM is established, based on which the attitude control model is derived, then the missile aerodynamic characteristics is analyzed according to the real data,Secondly, based on the Gauss Pseudospectral Method (GPM), the OTS turn phase is analyzed and the turn command is designed. In the establishment of mathematical optimization models, the attitude control system dynamics are ignored, and the maxim turn angle is selected as the performance index. The booster engine thrust, total impulse, and turn altitude factors are the emphasis of optimization analysis. Combined with the analysis results, the turn command is designed.Thirdly, based on State Dependent Riccati Equation (SDRE) theory, the OTS attitude control system is designed. The State Dependent Coefficient (SDC) models of pitch channel and lateral channel are derived according to the nonlinear attitude control model. Then the aerodynamic control subsystem and the reaction jet control subsystem are designed.Finally, the BTT Proportional Navigation Law (PNL) is deeply studied. Considering the characteristic of BTT control,the relative motion equation is established in the polar coordinate, based on which the mathematical model of BTT guidance system is obtained. Then BTT PNL is deeply analyzed. Theoretical and simulation analysis results show that the roll channel of the guidance loop is unstable when BTT missile approaches to terminal moment of the guidance phase.