Comparing Linear Parameter-Varying Gain-Scheduled Control Techniques for Active Flutter Suppression

Abstract

Two linear parameter-varying gain-scheduled controllers for active flutter suppression of the NASA Langley Research Center’s Benchmark Active Control Technology (BACT) wing section are presented and compared to a previously presented gain-scheduled controller. The BACT wing section changes significantly as a function of Mach and dynamic pressure. The two linear parameter-varying (LPV) gain-scheduled controllers incorporate these changes as well as bounds on the rate of change of Mach and dynamic pressure. The inclusion of rate bounds in the design process allows for improved performance over a larger range of operating conditions than previously achieved by a linear fractional transformation gain-scheduled controller. The LPV controllers differ in that one primarily reduces coupling between the trailing-edge flap and the pitch and plunge modes, whereas the second optimizes wind gust attenuation. Closed-loop stability and improved performance are demonstrated via time simulations in which both Mach and dynamic pressure are allowed to vary in the presence of a Dryden wind-gust disturbance.