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ICOLLIDE: An interactive and exact collision detection system for largescale environments
 In Proc. of ACM Interactive 3D Graphics Conference
, 1995
"... We present an exact and interactive collision detection system, ICOLLIDE, for largescale environments. Such environments are characterized by the number of objects undergoing rigid motion and the complexity of the models. The algorithm does not assume the objects ’ motions can be expressed as a c ..."
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Cited by 296 (25 self)
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We present an exact and interactive collision detection system, ICOLLIDE, for largescale environments. Such environments are characterized by the number of objects undergoing rigid motion and the complexity of the models. The algorithm does not assume the objects ’ motions can be expressed as a closed form function of time. The collision detection system is general and can be easily interfaced with a variety of applications. The algorithm uses a twolevel approach based on pruning multipleobject pairs using bounding boxes and performing exact collision detection between selected pairs of polyhedral models. We demonstrate the performance of the system in walkthrough and simulation environments consisting of a large number of moving objects. In particular, the system takes less than l/20 of a second to determine all the collisions and contacts in an environment consisting of more than a 1000 moving polytopes, each consisting of more than 50 faces on an HP9000/750. 1
Collision detection and response for computer animation
 In Proc. of Intl. Conf. on Computer Graphics and Interactive Techniques
, 1988
"... When several objects are moved about by computer animarion, there is the chance that they will interpenetrate. This is often an undesired state, particularly if the animation is seeking to model a realistic world. Two issues are involved: detecting that a collision has occurred, and responding to it ..."
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Cited by 245 (2 self)
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When several objects are moved about by computer animarion, there is the chance that they will interpenetrate. This is often an undesired state, particularly if the animation is seeking to model a realistic world. Two issues are involved: detecting that a collision has occurred, and responding to it. The former is fundamentally a kinematic problem, involving the positional relationship of objects in the world. The latter is a dynamic problem, in that it involves predicting behavior according to physical laws. This paper discusses collision detection and response in general, presents two collision detection algorithms, describes modeling collisions of arbitrary bodies using springs, and presents an analytical collision response algorithm for articulated rigid bodies that conserves linear and angular momentum.
Efficient Collision Detection for Animation and Robotics
, 1993
"... We present efficient algorithms for collision detection and contact determination between geometric models, described by linear or curved boundaries, undergoing rigid motion. The heart of our collision detection algorithm is a simple and fast incremental method to compute the distance between two ..."
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Cited by 115 (19 self)
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We present efficient algorithms for collision detection and contact determination between geometric models, described by linear or curved boundaries, undergoing rigid motion. The heart of our collision detection algorithm is a simple and fast incremental method to compute the distance between two convex polyhedra. It utilizes convexity to establish some local applicability criteria for verifying the closest features. A preprocessing procedure is used to subdivide each feature's neighboring features to a constant size and thus guarantee expected constant running time for each test. The expected constant time performance is an attribute from exploiting the geometric coherence and locality. Let n be the total number of features, the expected run time is between O( p n) and O(n) ...
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 47 (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
Interactive collision detection for molecular graphics
, 1989
"... Collision detection between hardsphere representations of molecules can be performed in interactive times on existing graphics hardware. This thesis presents a system that allows a user to interactively move a small drug molecule near a larger receptor molecule and have the system immediately infor ..."
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Cited by 42 (0 self)
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Collision detection between hardsphere representations of molecules can be performed in interactive times on existing graphics hardware. This thesis presents a system that allows a user to interactively move a small drug molecule near a larger receptor molecule and have the system immediately inform the user when a collision between the two molecules has occurred. The system uses a 3D grid data structure to speed up the search for collisions. The collision detection and the generation of images of the molecules are performed by the PixelPlanes 4 graphics engine. Preliminary trials of the system had users perform a simple geometric task, and the results indicate that stopping an object’s motion completely as the response to collisions is a hindrance to such tasks. This suggests that a better behavior for collision response must be found before collision response can aid in performing similar geometric tasks. Acknowledgements I would like to thank my thesis chair Professor Henry Fuchs, who has supplied ideas and encouragement throughout this project. I also thank Professor Frederick Brooks and Professor J. Nievergelt, the other members of my thesis committee, for the insightful suggestions and the encouragement
Collision detection for deforming necklaces
 IN SYMP. ON COMPUTATIONAL GEOMETRY
, 2002
"... In this paper, we propose to study deformable necklaces — flexible chains of balls, called beads, in which only adjacent balls may intersect. Such objects can be used to model macromolecules, muscles, rope, and other ‘linear ’ objects in the physical world. In this paper, we exploit this linearity ..."
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Cited by 37 (11 self)
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In this paper, we propose to study deformable necklaces — flexible chains of balls, called beads, in which only adjacent balls may intersect. Such objects can be used to model macromolecules, muscles, rope, and other ‘linear ’ objects in the physical world. In this paper, we exploit this linearity to develop geometric structures associated with necklaces that are useful in physical simulations. We show how these structures can be implemented efficiently and maintained under necklace deformation. In particular, we study a bounding volume hierarchy based on spheres built on a necklace. Such a hierarchy is easy to compute and is suitable for maintenance when the necklace deforms, as our theoretical and experimental results show. This hierarchy can be used for collision and selfcollision detection. In particular, we achieve an upper bound of O(nlog n) in two dimensions and O(n 2−2/d) in ddimensions, d ≥ 3, for collision checking. To our knowledge, this is the first subquadratic bound proved for a collision detection algorithm using predefined hierarchies. In addition, we show that the power diagram, with the help of some additional mechanisms, can be also used to detect selfcollisions of a necklace in certain ways complementary to the sphere hierarchy.
Rapid and Accurate Contact Determination between Spline Models using ShellTrees
, 1998
"... In this paper, we present an efficient algorithm for contact determination between spline models. We make use of a new hierarchy, called ShellTree, that comprises of spherical shells and oriented bounding boxes. Each spherical shell corresponds to a portion of the volume between two concentric spher ..."
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Cited by 25 (4 self)
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In this paper, we present an efficient algorithm for contact determination between spline models. We make use of a new hierarchy, called ShellTree, that comprises of spherical shells and oriented bounding boxes. Each spherical shell corresponds to a portion of the volume between two concentric spheres. Given large spline models, our algorithm decomposes each surface into Bezier patches as part of preprocessing. At runtime it dynamically computes a tight fitting axisaligned bounding box across each Bezier patch and efficiently checks all such boxes for overlap. Using offline and online techniques for tree construction, our algorithm computes ShellTrees for Bezier patches and performs fast overlap tests between them to detect collisions. The overall approach can trade off runtime performance for reduced memory requirements. We have implemented the algorithm and tested itonlarge models, each composed of hundred ofpatches. Its performance varies with the configurations of the objects. For many complex models composed of hundreds of patches, it can accurately compute the contacts in a few milliseconds.
A New Model for Efficient Dynamic Simulation
, 1993
"... This paper introduces a new model for rapid physical simulation called sparse dynamics. The method employs a quick first pass to identify likely object interactions. These are then flagged for more detailed analysis. As actual collisions are rare in a sparsely populated environment, efficiency is gr ..."
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Cited by 16 (0 self)
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This paper introduces a new model for rapid physical simulation called sparse dynamics. The method employs a quick first pass to identify likely object interactions. These are then flagged for more detailed analysis. As actual collisions are rare in a sparsely populated environment, efficiency is greatly increased. The first pass uses deterministic Newtonian mechanics to predict future collisions analytically, obviating the need to simulate small uniform time steps. Timings indicate this provides a large speed improvement over more traditional methods. In particular we were able to simulate full collision detections for 1000 polyhedra at real time speeds. We also discuss how to extend the sparse dynamics model to handle complex effects such as gravity, friction, and user interaction. 1 Motivation The graphics community has a tradition of viewing realtime dynamic simulation as intractable. While large strides have been made in realtime rendering and user interfaces, simulations invol...