Truth Cube: Establishing Physical Standards for Real Time Soft Tissue Simulation

Abstract

Accurate and real-time models of soft tissue behavior are key elements in the development of medical simulation systems. However, precise validation of these models remains a challenge. Currently, real-time modeling is at best validated against FEM models that have their own intrinsic limitations. This study is the first in a series that will develop physical standards resulting in a database of relevant information used to validate real-time soft tissue deformation. In this first study, a simple 8cm cube of silicone rubber with an exact pattern of embedded Teflon beads was tested in uniaxial compression while CT images were taken. The known material properties, geometry, and carefully controlled boundary conditions resulted in a complete set of volumetric displacement data. The results were also compared to an FEM analysis of an identical situation. This work has served as a proof of concept for a robust physical standard for use in validating real time models. A web site has been created to provide access to our database at: http://biorobotics.harvard.edu/truthcube /.