Surface collision detection for virtual prototyping

This paper presents an efficient collision detection algorithm designed to support assembly and maintenance simulation of complex assemblies. This approach exploits the surface knowledge, available from CAD models, to determine intersecting surfaces. It proposes a novel combination of Overlapping Axis-Aligned Bounding Box (OAABB) and R-tree structures to gain considerable performance improvements. This paper also shows an efficient traversal algorithm based on the R-tree structure of Axis-Aligned Bounding Boxes to determine intersecting objects and intersecting surfaces between three-dimensional components, for supporting the recognition of constraints in assembly and disassembly operations in virtual prototyping environments. The implementation of the proposed collision detection algorithm performs well against moderately complex industrial case studies. Current experimental results show that this implementation is effective in determining intersecting surfaces at interactive rates with moderately complex real case studies.info:eu-repo/semantics/publishedVersio

Improved Collision Detection and Response Techniques for Cloth Animation

In the animation of deformable objects, collision detection and response are crucial for the performance. Contrary to volumetric bodies, the accuracy requirements for the collision treatment of textiles are particularly strict because any overlapping is visible. Therefore, we apply methods specifically designed for deformable surfaces that speed up the collision detection. In this paper the efficiency of bounding volume hierarchies is improved by adapted techniques for building and traversing these hierarchies. An extended set of heuristics is described that allows to prune the hierarchy. Oriented inflation of bounding volumes enables us to detect proximities with a minimum of extra cost. Eventually, the distance of the mesh faces is computed accurately, and constraints respond to the collisions

Revisión de literatura de jerarquía volúmenes acotantes enfocados en detección de colisiones

(Eng) A bounding volume is a common method to simplify object representation by using the composition of geometrical shapes that enclose the object; it encapsulates complex objects by means of simple volumes and it is widely useful in collision detection applications and ray tracing for rendering algorithms. They are popular in computer graphics and computational geometry. Most popular bounding volumes are spheres, Oriented-Bounding Boxe s (OBB’ s), Axis-Align ed Bound ing Boxes (AABB’ s); moreover , the literature review includes ellipsoids, cylinders, sphere packing, sphere shells , k-DOP’ s, convex hulls, cloud of points, and minimal bounding boxe s, among others. A Bounding Volume Hierarchy is ussualy a tree in which the complete object is represented thigter fitting every level of the hierarchy. Additionally, each bounding volume has a cost associated to construction, update, and interference te ts. For instance, spheres are invariant to rotation and translations, then they do not require being updated ; their constructions and interference tests are more straightforward then OBB’ s; however, their tightness is lower than other bounding volumes. Finally , three comparisons between two polyhedra; seven different algorithms were used, of which five are public libraries for collision detection.(Spa) Un volumen acotante es un método común para simplificar la representación de los objetos por medio de composición de formas geométricas que encierran el objeto; estos encapsulan objetos complejos por medio de volúmenes simples y son ampliamente usados en aplicaciones de detección de colisiones y trazador de rayos para algoritmos de renderización. Los volúmenes acotantes son populares en computación gráfica y en geometría computacional; los más populares son las esferas, las cajas acotantes orientadas (OBB’s) y las cajas acotantes alineadas a los ejes (AABB’s); no obstante, la literatura incluye elipses, cilindros empaquetamiento de esferas, conchas de esferas, k-DOP’s, convex hulls, nubes de puntos y cajas acotantes mínimas, entre otras. Una jerarquía de volúmenes acotantes es usualmente un árbol, en el cual la representación de los objetos es más ajustada en cada uno de los niveles de la jerarquía. Adicionalmente, cada volumen acotante tiene asociado costos de construcción, actualización, pruebas de interferencia. Por ejemplo, las esferas so invariantes a rotación y translación, por lo tanto no requieren ser actualizadas en comparación con los AABB no son invariantes a la rotación. Por otro lado la construcción y las pruebas de solapamiento de las esferas son más simples que los OBB’s; sin embargo, el ajuste de las esferas es menor que otros volúmenes acotantes. Finalmente, se comparan dos poliedros con siete algoritmos diferentes de los cuales cinco son librerías públicas para detección de colisiones

Tighter bounding volumes for better occlusion culling performance

Bounding volumes are used in computer graphics to approximate the actual geometric shape of an object in a scene. The main intention is to reduce the costs associated with visibility or interference tests. The bounding volumes most commonly used have been axis-aligned bounding boxes and bounding spheres. In this paper, we propose the use of discrete orientation polytopes (\kdops) as bounding volumes for the specific use of visibility culling. Occlusion tests are computed more accurately using \kdops, but most importantly, they are also computed more efficiently. We illustrate this point through a series of experiments using a wide range of data models under varying viewing conditions. Although no bounding volume works the best in every situation, {\kdops} are often the best, and also work very well in those cases where they are not the best, therefore they provide good results without having to analyze applications and different bounding volumes

The Construction of Balanced Bounding-Volume Hierarchies using Spatial Object Median Splitting Method for Collision Detection

Finding two or more contact points between rigid bodies simulation is always a fundamental task in virtual environment. Furthermore, the contact point needs to be accurately reported as soon as possible within 30-60 frames per second (fps) between moving polyhedral. This article introduced an efficient splitting method that is able to divide the bounding-volume of Axis Aligned Bounding-Box (AABB) hierarchies into a balanced tree. The construction of well-balanced tree will helps to improve the speed of the intersection between rigid bodies’ objects

Unbounding discrete oriented polytopes

We propose an efficient algorithm to compute k-sided unbounding discrete oriented polytopes (k-UDOPs) in arbitrary dimensions. These convex polytopes are constructed for a fixed set of directions and a given center point. The interior of k-UDOPs does not intersect the scene geometry. We discuss several types of general geometric queries on these constructs, such as intersection with rays, and provide an empirical investigation on the limit of these shapes as the number of sides increases. In the 2D case, we extend our construction to planar shapes enclosed by arbitrary parametric boundaries with known derivative bounds

Unbounding discrete oriented polytopes

We propose an efficient algorithm to compute k-sided unbounding discrete oriented polytopes (k-UDOPs) in arbitrary dimensions. These convex polytopes are constructed for a fixed set of directions and a given center point. The interior of k-UDOPs does not intersect the scene geometry. We discuss several types of general geometric queries on these constructs, such as intersection with rays, and provide an empirical investigation on the limit of these shapes as the number of sides increases. In the 2D case, we extend our construction to planar shapes enclosed by arbitrary parametric boundaries with known derivative bounds