Soft Object Modelling with Generalised ChainMail — Extending the Boundaries of Web-based Graphics

Soft object modelling is crucial in providing realistic simulation of many surgical procedures. High accuracy is achievable using the Finite Element Method (FEM), but significant computational power is required. We are interested in providing Web-based surgical training simulation where such computational power is not available, but in return lower accuracy is often sufficient. A useful alternative to FEM is the 3D ChainMail algorithm that models elements linked in a regular, rectangular mesh, mimicking the behaviour of chain-mail armour. An important aspect is the ability to make topology changes for example by cutting – an aspect that FEM finds difficult. Our contribution is to extend the 3D ChainMail technique to arbitrary grids in 2D and 3D. This extends the range of applications that can be addressed by the ChainMail approach, to include surfaces and volumes defined on triangular and tetrahedral meshes. We have successfully deployed the algorithm in a Web-based environment, using VRML and Java linked through the External Authoring Interface