Gain-scheduling techniques for missile autopilot synthesis

This paper presents a comparison between the Controller Blending (CB) and the Gain Blending (GB) gain scheduling techniques, applied on a pitch-axis missile autopilot design problem. ℋ_∞ output feedback dynamic controllers with additional LMI pole placement constraints are designed for distinct operating points throughout the missile´s operating domain for use with the (CB) technique. The same controllers are converted to state feedback/observer based controllers for use with the (GB) technique via Youla parameterization. In both cases, a global nonlinear control law giving satisfactory results is designed by interpolation according to Mach number and only output reference information. The results are motivated by the need of maintaining strict performance and disturbance rejection constraints for the missile model using linear controller synthesis tools.