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35
OBBTree: A hierarchical structure for rapid interference detection
 Proc. ACM SIGGRAPH, 171–180
, 1996
"... {gottscha,lin,manocha}©cs. unc.edu We present a data structure and an algorithm for efficient and exact interference detection amongst complex models undergoing rigid motion. The algorithm is applicable to all general polygonal and curved models. It precomputes a hierarchical representation of mode ..."
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Cited by 660 (42 self)
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{gottscha,lin,manocha}©cs. unc.edu We present a data structure and an algorithm for efficient and exact interference detection amongst complex models undergoing rigid motion. The algorithm is applicable to all general polygonal and curved models. It precomputes a hierarchical representation of models using tightfitting oriented bounding box trees. At runtime, the algorithm traverses the tree and tests for overlaps between oriented bounding boxes based on a new separating axis theorem, which takes less than 200 operations in practice. It has been implemented and we compare its performance with other hierarchical data structures. In particular, it can accurately detect all the contacts between large complex geometries composed of hundreds of thousands of polygons at interactive rates, almost one order of magnitude faster than earlier methods.
Efficiently Approximating the MinimumVolume Bounding Box of a Point Set in Three Dimensions
 In Proc. 10th ACMSIAM Sympos. Discrete Algorithms
, 2001
"... We present an efficient O(n + 1/ε^4.5)time algorithm for computing a (1 + 1/ε)approximation of the minimumvolume bounding box of n points in R³. We also present a simpler algorithm (for the same purpose) whose running time is O(n log n+n/ε³). ..."
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Cited by 77 (12 self)
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We present an efficient O(n + 1/&epsilon;^4.5)time algorithm for computing a (1 + 1/&epsilon;)approximation of the minimumvolume bounding box of n points in R&sup3;. We also present a simpler algorithm (for the same purpose) whose running time is O(n log n+n/&epsilon;&sup3;). We give some experimental results with implementations of various variants of the second algorithm. The implementation of the algorithm described in this paper is available online [Har00].
Spherical shell: A higher order bounding volume for fast proximity queries
 In Proc. of Third International Workshop on Algorithmic Foundations of Robotics
"... Hierarchical data structures have been widely used to design e cient algorithms for interference detection for robot motion planning and physicallybased modeling applications. Most of the hierarchies involve use of bounding volumes which enclose the underlying geometry. These bounding volumes are u ..."
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Cited by 45 (8 self)
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Hierarchical data structures have been widely used to design e cient algorithms for interference detection for robot motion planning and physicallybased modeling applications. Most of the hierarchies involve use of bounding volumes which enclose the underlying geometry. These bounding volumes are used to test for interference orcompute distance bounds between the underlying geometry. The e ciency of a hierarchy is directly proportional to the choice ofabounding volume. In this paper, we introduce spherical shells, a higher order bounding volume for fast proximity queries. Each shell corresponds to a portion of the volume between two concentric spheres. We present algorithms to compute tight tting shells and fast overlap between two shells. Moreover, we show that spherical shells provide local cubic convergence to the underlying geometry. As aresult, in many cases they provide faster algorithms for interference detection and distance computation as compared toearlier methods. We also describe an implementation and compare it with other hierarchies. 1
BOXTREE: A Hierarchical Representation for Surfaces in 3D
, 1996
"... We introduce the boxtree, a versatile data structure for representing triangulated or meshed surfaces in 3D. A boxtree is a hierarchical structure of nested boxes that supports efficient ray tracing and collision detection. It is simple and robust, and requires minimal space. In situations where sto ..."
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Cited by 42 (7 self)
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We introduce the boxtree, a versatile data structure for representing triangulated or meshed surfaces in 3D. A boxtree is a hierarchical structure of nested boxes that supports efficient ray tracing and collision detection. It is simple and robust, and requires minimal space. In situations where storage is at a premium, boxtrees are effective alternatives to octrees and BSP trees. They are also more flexible and efficient than Rtrees, and nearly as simple to implement. Keywords: collision detection, hierarchical data structures, ray shooting. 1. Introduction In 1981 Ballard 1 presented a simple data structure for representing digitized curves by means of nested strips. This work is an attempt to generalize his strip tree structure to the case of surfaces in 3D. As is well known, curves can seem quite tame when compared to surfaces. For example, collision detection in 3D is orders of magnitude more difficult than in 2D. Expectedly, generalizing a strip tree into a boxtree raises a ...
Accelerated Proximity Queries Between Convex Polyhedra By MultiLevel Voronoi Marching
 Proc. of IEEE/RSJ International Conference on Intelligent Robots and Systems
, 2000
"... We present an accelerated proximity query algorithm between moving convex polyhedra. The algorithm combines Voronoibased feature tracking with a multilevelofdetail representation, in order to adapt to the variation in levels of coherence and speed up the computation. It provides a progressive re ..."
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Cited by 41 (13 self)
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We present an accelerated proximity query algorithm between moving convex polyhedra. The algorithm combines Voronoibased feature tracking with a multilevelofdetail representation, in order to adapt to the variation in levels of coherence and speed up the computation. It provides a progressive refinement framework for collision detection and distance queries. We have implemented our algorithm and have observed significant performance improvements in our experiments, especially on scenarios where the coherence is low. 1 Introduction Proximity queries, i.e. distance 1 computations and the closely related collision detection problems, are ubiquitous in robotics, design automation, manufacturing, assembly and virtual prototyping. The set of tasks include motion planning, sensorbased manipulation, assembly and disassembly, dynamic simulation, maintainability study, simulationbased design, tolerance verification, and ergonomics analysis. Proximity queries have been extensively stud...
Fast and Accurate Collision Detection for Haptic Interaction Using a Three DegreeofFreedom ForceFeedback Device
 In Proceedings of Virtual Reality Conference
"... We present a fast and accurate collision detection algorithm for haptic interaction with polygonal models. Given a model, we precompute a hybrid hierarchical representation, consisting of uniform grids (represented using a hash table) and trees of tightfitting oriented bounding box trees (OBBTrees ..."
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Cited by 39 (0 self)
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We present a fast and accurate collision detection algorithm for haptic interaction with polygonal models. Given a model, we precompute a hybrid hierarchical representation, consisting of uniform grids (represented using a hash table) and trees of tightfitting oriented bounding box trees (OBBTrees). At run time, we use hybrid hierarchical representations and exploit frametoframe coherence for fast proximity queries. We describe a new overlap test, which is specialized for intersection of a line segment with an oriented bounding box for haptic simulation and takes 4272 operations including transformation costs. The algorithms have been implemented as part of HCOLLIDE and interfaced with a PHANToM arm and its haptic toolkit, GHOST, and applied to a number of models. As compared to the commercial implementation, we are able to achieve up to 20 times speedup in our experiments and sustain update rates over 1000Hz on a 400MHz Pentium II. In practice, our prototype implementation can a...
A HardwareAssisted VisibilityOrdering Algorithm with Applications to Volume Rendering
 In Data Visualization (2001
, 2000
"... . We propose a hardwareassisted visibility ordering algorithm. From a given viewpoint, a (backtofront) visibility ordering of a set of objects is a partial order on the objects such that if object obstructs object , then precedes in the ordering. Such orderings are useful because the ..."
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Cited by 14 (3 self)
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. We propose a hardwareassisted visibility ordering algorithm. From a given viewpoint, a (backtofront) visibility ordering of a set of objects is a partial order on the objects such that if object obstructs object , then precedes in the ordering. Such orderings are useful because they are the building blocks of other rendering algorithms such as direct volume rendering of unstructured grids. The traditional way to compute the visibility order is to build a set of visibility relations (e.g., ), and then run a topological sort on the set of relations to actually get the partial ordering. Our technique instead works by assigning a layer number to each primitive, which directly determines the visibility ordering. Objects that have the same layer number are independent, and can be placed anywhere with respect to each other. We use a simple technique which exploits a combination of the z and stencil buffers to compute the layer number of each primitive...
SelfCustomized BSP Trees for Collision Detection
, 2000
"... The ability to perform efficient collision detection is essential in virtual reality environments and their applications, such as walkthroughs. In this paper we reexplore a classical structure used for collision detection  the binary space partitioning tree. Unlike the common approach, which a ..."
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Cited by 14 (1 self)
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The ability to perform efficient collision detection is essential in virtual reality environments and their applications, such as walkthroughs. In this paper we reexplore a classical structure used for collision detection  the binary space partitioning tree. Unlike the common approach, which attributes equal likelihood to each possible query, we assume events that happened in the past are more likely to happen again in the future. This leads us to the definition of selfcustomized data structures. We report encouraging results obtained while experimenting with this concept in the context of selfcustomized bsp trees. Keywords: Collision detection, binary space partitioning, selfcustomization. 1 Introduction Virtual reality refers to the use of computer graphics to simulate physical worlds or to generate synthetic ones, where a user is to feel immersed in the environment to the extent that the user feels as if "objects" seen are really there. For example, "objects" should m...