A new hyper-Prony calibration process is proposed. It is performed by an integrated calibration of the hyperelastic part plus Prony series viscoelastic part simultaneously.  It provides a better way to calibrate elastomeric/polymeric materials. The derivation of the new calibration equations is going to be presented in the future 3D Experience. I post two demonstration videos of the calibration of a Yeoh hyperelastic plus Prony series viscoelastic material model to a series of pseudo experimental results, the first one of them is the calibration of hyperelastic material only and the second one is for the hyper-viscoelastic material.

The motivation for this new process is that, currently, in order to calibrate this kind of material model in the Abaqus environment (A/CAE ; batch Pre), the constitutive relation has to be divided into two steps. This also means that the user must separate the test data into two parts.  In the first step, a purely hyperelastic model regardless of dissipation is considered with the existing models like Neo-Hookean model, Ogden model, Yeoh model, etc.. The hyperelastic constants in these models can be calibrated from the experimental data. The second step is viscoelastic calibration, where stress is rate dependent. The problem of this method is that, in most cases, viscous relaxation may occur in the hyperelastic step, elimination of viscoelastic behavior may affect the calibration; and separation of the experimental data into two parts is inappropriate.  A new hyper-Prony calibration process is proposed to derive the hyperelastic parameters and the Prony series parameters simultaneously. The new approach is more reasonable since viscous behavior in the hyperelastic region is considered and experimental data can be directly used for the calibration. 

Please let me know if you have any questions about the calibration, I would be very pleased to reply. My email address is lizhang2013@u.northwestern.edu.