Photoelastic stress analysis error quantification in vasculature models for robot feedback control

Real-time and accurate stress calculation in walls of vasculature is desired to provide catheter insertion robots of feedback control without changing the catheter stiffness and lumen. This feedback source has also applications in endovascular surgery simulation for human skills and medical tools evaluation. For that purpose we consider photoelastic effect, as birefringence produced by light retardation relates with the stress inside the photoelastic materials. In this research a polariscope was designed for urethane elastomer vasculature models, the photoelastic coefficient of urethane elastomer was measured, and the camera system was calibrated to quantify and reduce error of the measurement system. An average error of 3.6% was found for the pressure range of 70-189 mmHg inside the model of urethane elastomer, this enables to calculate accurately stress in vasculature models during Human Blood Pressure Simulation (HBPS). That way we will be able to compare in a closed loop stress produced by HBPS and by the catheter motion when manipulated by a robot.