Estimation of parameters for dynamic volume spline models

Abstract

Soft tissue models are of many types, but each type has its own problems in terms of realistic appearance and computational efficiency. In this study, we propose a hybrid model based on dynamic volume splines which combine the advantages of these models. To simulate a realistic appearance, biomechanical properties of the real tissue are obtained by force–displacement experiments and used to tune the parameters of the model. Unlike the usual types described in the literature, a new experiment is proposed where displacement is measured not only for the point of force application but also for the region around the applied force. In our study, multiple camera views were used to enable 3D reconstruction of the surface. The differences arising between the surfaces obtained before and after the application of force were then used in optimization-based inverse solution methods, and the estimated parameters were found to be consistent with the biomechanical tissue properties described in the literature.

Keywords:

• dynamic soft tissue model
• 3D reconstruction
• surface fitting
• parameter estimation
• inverse solution
• optimization

Acknowledgements

This study is partially supported by TUBITAK 105E128 and BAP-2008-03-01-04.