Reduced Order Aeroservoelastic Models with Rigid Body Modes

Complex aeroelastic and aeroservoelastic phenomena can be modeled on complete aircraft configurations generating models with millions of degrees of freedom. Starting from a freely supported version of the model, a two-step model reduction process is proposed to create aeroelastic models that include rigid body dynamics. In the first step, proper orthogonal decomposition at a set of flight conditions reduces the model order from millions to hundreds of degrees of freedom. In the second step, a linear matrix inequality further reduces the order and creates a linear parameter varying reduced order model. The model includes a trimmed and parameterized description of aeroelastic forces valid over a region of the flight envelop. The same model can be used for rapid simulation and for linear parameter varying flight control design. Feasibility of this two-step process has been demonstrated in the Phase I work and a plan has been developed for a prototype implementation. Specific improvements to the rigid body model, technical risks in the development effort, and a risk reduction plan have been identified. An X-56A vehicle model will be developed and then used to demonstrate the model reduction process and to demonstrate applications including a linear parameter varying flight control system.