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Modeling aircraft wing loads from flight data using neural networks
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Dibley, Ryan P. Allen, Michael J. |
| Copyright Year | 2003 |
| Description | Neural networks were used to model wing bending-moment loads, torsion loads, and control surface hinge-moments of the Active Aeroelastic Wing (AAW) aircraft. Accurate loads models are required for the development of control laws designed to increase roll performance through wing twist while not exceeding load limits. Inputs to the model include aircraft rates, accelerations, and control surface positions. Neural networks were chosen to model aircraft loads because they can account for uncharacterized nonlinear effects while retaining the capability to generalize. The accuracy of the neural network models was improved by first developing linear loads models to use as starting points for network training. Neural networks were then trained with flight data for rolls, loaded reversals, wind-up-turns, and individual control surface doublets for load excitation. Generalization was improved by using gain weighting and early stopping. Results are presented for neural network loads models of four wing loads and four control surface hinge moments at Mach 0.90 and an altitude of 15,000 ft. An average model prediction error reduction of 18.6 percent was calculated for the neural network models when compared to the linear models. This paper documents the input data conditioning, input parameter selection, structure, training, and validation of the neural network models. |
| File Size | 862876 |
| Page Count | 20 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20030075758 |
| Archival Resource Key | ark:/13960/t4hn0642b |
| Language | English |
| Publisher Date | 2003-09-01 |
| Access Restriction | Open |
| Subject Keyword | Aircraft Design, Testing And Performance Flight Tests Root-mean-square Errors Neural Nets Data Processing F-18 Aircraft Optimization Bending Moments Nonlinearity Mathematical Models Aeroelasticity Wing Loading Aeroelastic Research Wings Loads Forces Flight Simulation Mach Number Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
