Identification of systems containing nonlinear stiffnesses using backbone curves
Mechanical Systems and Signal Processing
Open Access funded by Engineering and Physical Sciences Research Council. Under a Creative Commons license: http://creativecommons.org/licenses/by/4.0/
This paper presents a method for the dynamic identification of structures containing discrete nonlinear stiffnesses. The approach requires the structure to be excited at a single resonant frequency, enabling measurements to be made in regimes of large displacements where nonlinearities are more likely to be significant. Measured resonant decay data is used to estimate the system backbone curves. Linear natural frequencies and nonlinear parameters are identified using these backbone curves assuming a form for the nonlinear behaviour. Numerical and experimental examples, inspired by an aerospace industry test case study, are considered to illustrate how the method can be applied. Results from these models demonstrate that the method can successfully deliver nonlinear models able to predict the response of the test structure nonlinear dynamics.
This work was funded by the Engineering and Physical Sciences Research Council (EPSRC) in the UK as part of the Engineering Nonlinearity Programme Grant EP/K003836/1. Prof. S. A. Neild is supported by the EPSRC FellowshipEP/K005375/1 and Prof. J.E. Cooper is supported by the Royal Academy of Engineering in the UK through the RAEng Airbus Sir George White Chair in Aerospace Engineering. This financial support is gratefully acknowledged.
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.
Available online 4 March 2016