The European Commission has granted the WebSET consortium, co-ordinated by the MVC under the contract reference IST-1999-10632, to fund further research and development of a standardised suite of interactive three-dimensional educational tools for surgical training over the World Wide Web. The simulations all involve the introduction and insertion of a needle or catheter into the body, in order to puncture or pierce internal tissue. To date, the work has focused on the development of techniques to improve the feedback given to the user.
The Lumbar Puncture simulator has been created in order to simulate the procedure of the same name, where a needle is used to pierce the membrane surrounding the spinal chord. When performing this procedure for real, the doctor or surgeon will experience a popping sensation the moment when the needle reaches and punctures its target. This effect is difficult to re-create on a computer display, and so originally a sound was played to represent this event. A better approach would be to provide some tactile feedback to the user, by means of a force feedback device, such as a force feedback mouse. It is in the development of such a technique that ParallelGraphics' Cortona SDK was used.
A technique was developed to allow VRML to communicate with Logitech's WingMan Force Feedback Mouse. Data needs to be both sent to, and read from the mouse, in order to synchronise and control haptic effects. The most obvious way of performing this task was to utilise VRML's EAI and Java, in order to communicate with the C++ SDK controlling force feedback effects. Due to applet security restrictions though and the general complexity of communicating between so many technologies, a different approach was required.
According to the simulator's developers, Cortona SDK provided the perfect solution to their problems. The embedding of Cortona VRML Client into an MFC application and using Cortona SDK as a programming interface into the VRML scene, made it possible to communicate between VRML and the force feedback SDK, with the minimum of effort. The mouse movement can now be monitored and used to control the needle motion in the simulator. Collision detection results can be detected, allowing for the facilitation of the appropriate haptic effects. The documentation and examples included within the Cortona SDK, proved extremely helpful to the developers of this unique medical simulation and greatly aided the development process.
ParallelGraphics is headquartered in Dublin, Ireland, with a major Research & Development centre in Moscow. The company is a world leader in the field of the 3D Internet technologies with over ten years of experience in the creation of unique 3D multi-user Internet services and software products. ParallelGraphics offers complete turnkey 3D services and a comprehensive range of interactive 3D products. ParallelGraphics' technologies have strong applications in the areas of education, entertainment and e-commerce. To know all about the WebSET project, you can read the VMW July 2000 article Virtual multi-user environment to provide surgical training and physiological education via the Web.