Classical Control Design Feasibility Study with BFF Models

Abstract

This working paper documents an initial control feasibility study to determine if classical control techniques could be utilized to favorably augment the stability of the BFF vehicle. This study focused on the lower speed models which have stable, or slightly unstable aeroelastic dynamics. Future studies will explore the higher speed models with highly unstable aeroelastic modes. The final control solution will incorporate stability augmentation with aeroelastic suppression, including flutter suppression to stabilize the vehicle beyond the flutter boundary. The principal goal is a defined strategy, process and supporting software tools to develop a full envelope controller for flexible aeroelastic vehicles with significant rigid body and flexible coupling. Focus will be on blended wing-body vehicle designs like the BFF and X-56A. The purpose of this study is a background feasibility investigation.