Recently, surgical simulation is a widely used method to train surgeons on specific surgeries due to the fact that it helps reducing surgical errors. Available surgical simulations lack realism since they only incorporate one or two senses which are vision and hap tic. This paper proposes a novel multimode interactive surgical simulator that incorporates hap tic, olfactory, as well as traditional vision feedback. A scent diffuser was created and developed to interact with the simulation, in order to produce odors when errors took place. Phantom hap tic device was used to provide the sense of touch to the user. Our system has been tested and evaluated and the results show that incorporating more senses to the simulation enhances the performance of the user. This is due to the fact that using olfaction sensation increases the remembrance of the trainee.

The exact Minkowski sum of polyhedra is of particular interest in many applications, ranging from image analysis and processing to computer-aided design and robotics. Its computation and implementation is a difficult and complicated task when nonconvex polyhedra are involved. We present the NCC-CVMS algorithm, an exact and efficient contributing vertices-based Minkowski sum algorithm for the computation of the Minkowski sum of a nonconvex--convex pair of polyhedra, which handles nonmanifold situations and extracts eventual polyhedral holes inside the Minkowski sum outer boundary. Our algorithm does not output boundaries that degenerate into a polyline or a single point. First, we generate a superset of the Minkowski sum facets through the use of the contributing vertices concept and by summing only the features (facets, edges, and vertices) of the input polyhedra which have coincident orientations. Secondly, we compute the 2D arrangements induced by the superset triangles intersections. Finally, we obtain the Minkowski sum through the use of two simple properties of the input polyhedra and the Minkowski sum polyhedron itself, that is, the closeness and the two-manifoldness properties. The NCC-CVMS algorithm is efficient because of the simplifications induced by the use of the contributing vertices concept, the use of 2D arrangements instead of 3D arrangements which are difficult to maintain, and the use of simple properties to recover the Minkowski sum mesh. We implemented our NCC-CVMS algorithm on the base of CGAL and used exact number types. More examples and results of the NCC-CVMS algorithm can be found at: http://liris.cnrs.fr/hichem.barki/mksum/NCC-CVMS

We present a new algorithm, based on the concept of contributing vertices, for the exact and efficient computation of the Minkowski difference of convex polyhedra. First, we extend the concept of contributing vertices for the Minkowski difference case. Then, we generate a Minkowski difference facets superset by exploiting the information provided by the computed contributing vertices. Finally, we compute the Minkowski difference polyhedron through the trimming of the generated superset. We compared our Contributing Vertices-based Minkowski Difference (CVMD) algorithm to a Nef polyhedra-based approach using Minkowski addition, complement, transposition, and union operations. The performance benchmark shows that our CVMD algorithm outperforms the indirect Nef polyhedra-based approach. All our implementations use exact number types, produce exact results, and are based on CGAL, the Computational Geometry Algorithms Library.

We present an original approach for the computation of the Minkowski sum of a non-convex polyhedron without fold and a convex polyhedron, without decomposition and union steps-that constitute the bottleneck of convex decomposition-based algorithms. A non-convex polyhedron without fold is a polyhedron whose boundary is completely recoverable from three orthographic projections defined by three orthogonal basis vectors in Ropf3. First, we generate a superset of the Minkowski sum facets using the concept of contributing vertices we accommodate for a non-convex-convex pair of polyhedra. The generated superset guarantees that its envelope is the boundary of the Minkowski sum polyhedron. Secondly, we extract the Minkowski sum facets and handle the intersections among the superset facets by using 3D envelope computation. Our approach is limited to non-convex polyhedra without fold because of the use of 3D envelope computation to recover the Minkowski sum boundary. Models with holes are not handled by our method. The implementation of our algorithm uses exact number types, produces exact results, and is based on CGAL, the Computational Geometry Algorithms Library.