ACTIVE CONTROL OF AEROTHERMOELASTIC EFFECTS FOR A CONCEPTUAL HYPERSONIC AIRCRAFT

This article describes the procedures and results of aeroservothermoelastic studies. The objectives of these studies are to develop the necessary procedures for performing an aeroelastic analysis of an aerodynamically heated vehicle and to analyze a configuration in the classical ''cold'' state and in a ''hot'' state. Major tasks include the development of the structural and aerodynamic models, open loop analyses, design of active control laws for improving dynamic responses, and analyses of the closed loop vehicles. The analyses performed focused on flutter speed calculations, short period eigenvalue trends, and statistical analyses of the vehicle response to controls and turbulence. Improving the ride quality of the vehicle, and raising the flutter boundary of the aerodynamically heated vehicle up to that of the cold vehicle, were the objectives of the control law design investigations.