Model Updating of a Nonlinear System: Gun Barrel of a Battle Tank

Canbaloglu, Guvenc
Özgüven, Hasan Nevzat
Nonlinearities in a structural system make the use of model updating methods developed for linear systems difficult to apply nonlinear systems. If the FRFs of the underlying linear systems in a nonlinear system could be experimentally extracted, then the linear model updating methods could easily be applied to nonlinear systems as well. When there are complex nonlinearities in a structure together with frictional type of nonlinearity, linear FRFs cannot be accurately obtained by using low level forcing. In this present work, the model updating method-Pseudo Receptance Difference (PRD) method-recently developed by the authors for nonlinear systems, is applied to the gun barrel of a battle tank. The linear FRFs of the nonlinear gun barrel of the battle tank are obtained from measured nonlinear FRFs, and simultaneously the nonlinearities in the system are identified. Then the inverse eigensensitivity method is employed to update the linear finite element (FE) model of the gun barrel. Finally, in order to demonstrate the accuracy of the updated nonlinear model, the calculated and measured FRFs of the gun barrel at several different forcing levels are compared.


Experimental validation of pseudo receptance difference (PRD) method for nonlinear model updating
Canbaloglu, Guvenc; Özgüven, Hasan Nevzat (Springer, 2015-02-05)
In real life applications most of the structures have nonlinearities, which restrict us applying model updating techniques available for linear structures. Well-established FRF based model updating methods would easily be extended to a nonlinear system if the FRFs of the underlying linear system (linear FRFs) could be experimentally measured. When frictional type of nonlinearity co-exists with other types of nonlinearities, it is not possible to obtain linear FRFs experimentally by using low level forcing. ...
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Citation Formats
G. Canbaloglu and H. N. Özgüven, “Model Updating of a Nonlinear System: Gun Barrel of a Battle Tank,” 2016, Accessed: 00, 2020. [Online]. Available: