Genetic Algorithm Optimisation of Mathematical Models — An Aircraft Structural Dynamics Case Study
Summary
In this paper, a technique for tackling inverse problems in structural dynamics will be reviewed. The processes applied here involve using the artificial intelligence optimisation tool known as genetic algorithms (GAs) where the optimisation problem to be tackled involves creating a structural dynamic aircraft model that best matches the available experimental frequency response function (FRF) data. It will be demonstrated how the inverse structural problem is difficult for more traditional optimisation approaches and how the stochastic processes inherent in a GA allow the problem to be tractable. Unsteady aerodynamic modelling is then used in conjunction with the structural models for aeroelastic analyses to determine the airspeed at which instabilities (commonly known as flutter) will arise. The implications of such model optimisation on aeroelastic analyses, and the estimates of uncertainty that may then be made, will also be briefly discussed.
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References
- [1]J.A. Nelder and R. Mead: “A Simplex Method for Function Minimization.”, Comput. J. 7, 1965, 308–313.MATHGoogle Scholar
- [2]S.A. Dunn: “Modified Genetic Algorithm for the Identification of Aircraft Structures.” J. Aircraft, 34, 2, (1997), 251–253CrossRefGoogle Scholar
- [3]S. Dunn and S. Peucker: “Genetic Algorithm Optimisation of Mathematical Models Using Distributed Computing.”, Proceedings of The Fifteenth International Conference on Industrial & Engineering Applications of Artificial Intelligence & Expert Systems, Cairns, Australia, June 17 20, 2002.Google Scholar
- [4]J.H. Holland: “Genetic Algorithms.”, Scientific American, July (1992) pp4450.Google Scholar
- [5]S. Forrest: “Genetic Algorithms: Principles of Natural Selection Applied to Computation.”, Science, 261, (1993) pp872–878.CrossRefGoogle Scholar
- [6]D.E. Goldberg: “Genetic Alorithms in Search Optimization & Machine Learning.”, Addison—Wesley Publishing Company, inc. Reading MA, USA (1989)Google Scholar
- [7]M. Mitchell: “An Introduction to Genetic Algorithms.”, The MIT Press, Cambridge, MA, USA (1996) .Google Scholar
- [8]M. Dickinson: “CF-18/GBU24 Ground Vibration Test Report.” Bombardier Inc. Canadair, Montreal, Canada, (1995) .Google Scholar
- [9]S.A. Dunn: “Optimised Structural Dynamic Aircraft Finite Element Models Involving Mass, Stiffness and Damping Elements.” International Forum on Aeroelasticity and Structural Dynamics, Madrid, Spain, 5–7 June, (2001), 387 396Google Scholar
- [10]S.A. Dunn: “Technique for Unique Optimization of Dynamic Finite Element Models.” J. Aircraft, 36, 6, (1999), 919–925CrossRefGoogle Scholar
- [11]E. Albano and W.P. Rodden: “A Doublet—Lattice Method for Calculating Lift Distributions on Oscillating Surfaces in Subsonic Flows.”, AIAA Journal, 7, 1969, p.2192CrossRefGoogle Scholar