Identification of complex moduli for rubber compounds by minimisation of the error between measured and FE-modelled velocity profiles
Paper in proceedings, 2006
For all research that involves understanding of the contact between tyre and road surface, knowledge
of the tyres dynamical material properties is of importance. A method for identification of
the complex moduli, i.e. dynamic stiffness and damping, of rubber tread materials is presented.
The method is based on a velocity profile match between FE-models and measurements. The
measurements are conducted on beam-like samples with a laser Doppler vibrometer, giving only
insignificant errors due to measurement interference. The specified material parameters are updated
in the FE-model in order to minimise the sum of the squared errors between measured and
modelled velocity data. This optimisation problem is solved with a gradient descent algorithm,
where a one-dimensional wave model provides initial values. This identification method may
be used at higher frequencies for highly damped materials, and do not show the limitations of
methods only evaluating the material at resonance frequencies. The method gives a consistent
identification in a wide frequency range.