Guided Bombs Tilt Turn The Flight Control System Design And Simulation Study

Bank-to-Turn (BTT) control technology has aroused wide concern among researchers in the design of the long-range guided weapons, powered by ramjet, with symmetrical structure. It makes the largest lifting surface of the missile turn quickly to the ideal motor direction through the roll control in the process of the BTT missile's flying to the target, while making the pitch channel control the missile to produce the required maneuvering acceleration with the largest missile lifting surface. This obviously improves the maneuverability of the missile, and has a great impact on increasing the range of the missile. The characteristic of the BTT control method determines that the mathematical model contains many coupling elements, including kinematical coupling, inertial coupling etc. To eliminate the channel coupling, to enhance the robustness and stability of the control system are the key points of the design.This thesis, based on view of engineering practice, studies the flight control system of the gliding range guided bomb, establishes the BTT mathematical model of the guided bomb based on the characteristics of kinematics and dynamics, analyzes the coupling between each channel and designs the BTT autopilot as well. The main contents include:Firstly, based on classical control theory, a traditional method of designing 3-channel independently is adopted in the process of designing the controllers of each channel. Then, coupling among the 3-channel is constrained by introducing a coordinated loop, and BTT control is thereby achieved.Secondly, since the guidance commands in gliding flight change slowly, this thesis treats the coupling effects between the 3-channel as bounded disturbances in designing the 3-channel controllers. Based on the idea of satisfactory control, H-infinity state feedback control that has regional pole constraints based on LMI methods used to design the autopilot, and assigned the closed loop poles within an appropriate expected region. It meets the dynamic performance requirements and achieves BTT control.Finally, analyzes the BTT guidance law, and gives the guidance commands formula for the BTT proportional guidance law, which takes into account gravity compensation.As is demonstrated by theoretical analysis and digital simulation, both two methods of the autopilot design have achieved good control effects. The works in this thesis will serve as helpful references for future engineering practices.