F-16 Longitudinal Stabilization using Hinf Output Feedback
The linearized longitudinal dynamics of the F-16 aircraft are considered in this example. The nonlinear 6DOF model is linearized using straight-and-level flight conditions of:
The state-space representation for the linearized longitudinal dynamics can be written as follows:
where , , , and are the state variable, control input, disturbance, and regulated output vectors, respectively. In this case, is velocity (ft/s), is angle of attack (rad), is pitch (rad), is pitch rate (rad/s), is elevator deflection with respect to trimmed deflection (rad), is commanded elevator deflection with respect to trimmed deflection (rad), and is normal acceleration at the pilot location (ft/s^2).
Using this problem formulation, an output controller can be found that attenuates normal acceleration and tracks reference elevator deflection command.