AIAA Atmospheric Flight Mechanics Conference and Exhibit, 2008 (Scopus)
Wind tunnel testing methods often infer aerodynamic performance via quasi-steady predictions, driving a wind tunnel model through predetermined trajectories, or quasi- steady integration of the applied aerodynamic forces and moments. This paper focuses on a new testing approach that allows the simulation and study of the true longitudinal dynamics of a wind tunnel model. The system design allows an experimentalist to carry heavy models with all of the needed sensors for evaluating true unsteady aerodynamic flight qualities. Controlling the forces and moments applied to the model allows the experimentalist to remove effects such as gravity and traverse friction. Using feedback on the applied force and moments, the dynamic characteristics of the model can be actively modified to alter dynamic characteristics such as the system's natural frequency, damping, c.g. location, and/or effective model inertia. All dynamic effects can be set arbitrarily but must be within traverse limits. The model does not have to be balanced because the control system actively restricts motion to be within the longitudinal plane. An example experimental simulation flight is shown using a NACA 4415 wing section with a servo motor in torque mode to simulate the effect of a conventional tail surface. Copyright © 2008 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.