Real-Time Methods for Adaptive Suppression of Adverse Aeroservoelastic Dynamics

Adverse aeroservoelastic (ASE) interaction is a problem on new and existing aircraft of all types causing repeated loading, enhanced fatigue and undesirable oscillations for pilots. Traditionally, to suppress adverse ASE interaction, notch and/or roll off filters have been utilized in the flight control system architecture to effectively "cancel out" problematic frequencies that will potentially excite the ASE dynamics. This solution has pitfalls; rigid body performance is degraded due to the resulting phase penalty and the filter is not robust to unexpected or un-modeled off nominal behavior. STI proposes an adaptive approach, which is leveraged by the adaptive Higher Harmonic Control (HHC) algorithm for high frequency disturbance rejection. This adaptive approach is robust to system variations, minimizes lower frequency phase penalty, and has been utilized for similar dynamic systems with supporting experimental validation. Development of the adaptive HHC algorithm for ASE suppression will be accomplished utilizing a high fidelity model of a representative high-speed fighter aircraft that is capable of parameter variation consisting of flight condition changes, configuration changes (stores configurations) as well as damage and failures. Validation of the proposed approach will be accomplished via simulation with representative parameter variations. Validation via real-time piloted simulations is proposed for future studies.