Control Allocation Strategies for a Hybrid Controlled Missile with NDI Autopilot

Abstract

This study presents roll angle, lateral, and longitudinal acceleration autopilots for a highly agile air defense missile with both aerodynamic tail control and thrust vector control (TVC) parts. Nonlinear Dynamic Inversion (NDI) is studied to handle bank-to-turn and agile maneuvers due to the cross-coupling effects. Output redefinition is implemented using the center of percussion idea for the nonminimum phase of the tail-controlled missiles. Another arduous feature of the system is that the dual control of the system generates a need to allocate the control between aerodynamic and thrust control. Driving aerodynamic fins and jet vanes with the same actuator is found preferable for some systems that creates a mechanically coupled or, in other words, integrated design. Further, this paper shows the effect of allocating control with or without this mechanical coupling.