Development of a real-time visual and force environment for a haptic medical training simulator

In this article, a real-time, visual and force environment for a 5-dof haptic urological training simulator is presented that deals with a low-force, high-deformation environment. A real-time graphical representation of the male urethra during the insertion of an endoscope is developed. Smooth urethra deformations are produced by a mesh of piece-wise Bézier interpolations, while its inner wall is simulated by realistic tissue textures. Efficient real-time techniques are developed that introduce endoscope camera depth-of-field effects. A novel particle-based model computes in real-time the forces fed to the haptic device. A 13 fps refresh rate is achieved on a 2-GHz computer with the depth-of-field effect activated, while the rate is doubled to 26 fps with this feature disabled. It is expected that the simulator will contribute to ethical, efficient, and modern surgical training.