Performance Optimizing Gust Load Alleviation Control of Flexible Wing Aircraft

This paper details a control design for flexible wing aircraft that attempts to minimize the load induced by gust disturbance. Wing root bending moment is taken as an available measure of gust load and is used in a performance optimizing cost function to determine the load-alleviating control signal. However, both the disturbance signal and system matrices associated with wing root bending moment are unknown quantities. Estimates are instead generated online and used to complete the control formulation. Use of the time-varying matrix estimates in the performance index necessitates solving a Riccati equation at each time step and results in time-varying control gains. The control system is simulated on a reduced stiffness transport aircraft equipped with a wing shaping flap design and is seen to significantly reduce the load metric.