Multi-Degree-of-Freedom Wind-Tunnel Maneuver Rig for Dynamic Simulation and Aerodynamic Model Identification

John Pattinson, Mark Lowenberg, Mikhail Goman

Journal of Aircraft · 2012 · 49 citations · 28 references

Concepts

TL;DR

The rig permits controlled wind‑tunnel execution of a wide range of aircraft maneuvers, using remotely controlled stabilator and aerodynamic compensator deflections to excite longitudinal modes, with two configurations (pitch only and pitch with heave) and separate modeling of tail and wing to identify pitch‑rate stability derivatives. The developed five‑degree‑of‑freedom rig, along with its mathematical model, enabled identification of a quasi‑steady longitudinal aerodynamic model for a subscale aircraft, accurate parameter estimation, and demonstration of its capabilities through physical simulation time histories from experiments with up to four degrees of freedom.

Abstract

A new five-degree-of-freedom rig for the dynamic wind-tunnel testing of aircraft models has been developed. The maneuver rig enables a large set of conventional and more-extreme aircraft maneuvers to be performed in the controlled environment of a wind tunnel, allowing direct physical simulation of in-flight maneuvers and the identification of aerodynamic models from aircraft-model time histories. A mathematical model of the rig has been developed for numerical simulation and identification purposes. The development of a quasi-steady aerodynamic model of the longitudinal motion for a subscale test aircraft is presented to illustrate rig capabilities. The longitudinal modes of motion are excited by a remotely controlled aircraft-model stabilator and dynamic-rig aerodynamic compensator deflections. Two rig configurations are considered: aircraft-model pitch only and aircraft-model pitch with heave, which is implemented via rig-pitch motion. The aircraft-model tail and wing in the mathematical model are considered separately to assist in identifying and pitch-rate stability derivatives. The results of parameter estimation are presented with analysis of their accuracy. Last, to further explore the rig's potential, physical simulation time histories from three experiments using two, three, and four of the available degrees of freedom are presented and discussed.

References

28