Flight Control Algorithms for a Vertical Launch Air Defense Missile
The necessity of high maneuverability and vertical launching require thrust vector control additional to aerodynamic control. That hybrid usage of aerodynamic and thrust vectoring controls effectively increases the agility of the missile against air defense threats. This requirement and the rapidly changing dynamics of this type of missiles renders the guidance and control design critical. However, the findings suggest that classical guidance and control design approaches are still valuable to apply and can have successful performance within the effective flight envelope. It is very rare that a study concerns from detailed dynamics and analysis of the dynamics covering flight mission and algorithms. In this study, together with the modeling of the agile dynamics of a vertical launch surface to air missile and the corresponding thrust forces and moments depending on linear supersonic theory, the application of the flight control algorithms are presented. Two classic linear autopilot structures are studied. During autopilot design process, an additional term related to short period dynamics of boost phase is proposed and the drastic effect of this term is shown. In addition to control algorithms, guidance algorithms are also defined to fulfill the mission of the missile. Body pursuit algorithm is applied for rapid turnover maneuver and midcourse guidance. Proportional navigation guidance is chosen for terminal phase. In addition, an alternative maneuvering technique is proposed to reduce further side slip angle during vertical flight.