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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 ..."
Abstract

Cited by 266 (26 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
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 108 (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) ...
The HUMANOID Environment for Interactive Animation of Multiple Deformable Human Characters
 Proceedings of Eurographics '95
, 1995
"... We describe the HUMANOID environment dedicated to human modeling and animation for general multimedia, VR, and CAD applications integrating virtual humans. We present the design of the system and the integration of the various features: generic modeling of a large class of entities with the BODY dat ..."
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Cited by 59 (41 self)
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We describe the HUMANOID environment dedicated to human modeling and animation for general multimedia, VR, and CAD applications integrating virtual humans. We present the design of the system and the integration of the various features: generic modeling of a large class of entities with the BODY data structure, realistic skin deformation for body and hands, facial animation, collision detection, integrated motion control and parallelization of computation intensive tasks.
A Simple and Efficient Method for Accurate Collision Detection Among Deformable Polyhedral Objects in Arbitrary Motion
 Proc. of the IEEE Virtual Reality Annual International Symposium
, 1995
"... We propose an accurate collision detection algorithm for use in virtual reality applications. The algorithm works for threedimensional graphical environments where multiple objects, represented as polyhedra (boundary representation), are undergoing arbitrary motion (translation and rotation). The a ..."
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Cited by 30 (3 self)
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We propose an accurate collision detection algorithm for use in virtual reality applications. The algorithm works for threedimensional graphical environments where multiple objects, represented as polyhedra (boundary representation), are undergoing arbitrary motion (translation and rotation). The algorithm can be used directly for both convex and concave objects and objects can be deformed (nonrigid) during motion. The algorithm works efficiently by first reducing the number of face pairs that need to be checked accurately for interference by first localizing possible collision regions using bounding box and spatial subdivision techniques; face pairs that remain after this pruning stage are then accurately checked for interference. The algorithm is efficient, simple to implement, and does not require any memory intensive auxiliary data structures to be precomputed and updated. Since polyhedral shape representation is one of the most common shape representation schemes, this algorithm...
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 15 (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...
Efficient Contact Determination Between Geometric Models
 INTERNATIONAL JOURNAL OF COMPUTATIONAL GEOMETRY AND APPLICATIONS
"... The problem of interference detection or contact determination between two or more objects in dynamic environments is fundamental in computer graphics, robotics and computer simulated environments. Most of the earlier work is restricted to either polyhedral models or static environments. In this pap ..."
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Cited by 11 (3 self)
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The problem of interference detection or contact determination between two or more objects in dynamic environments is fundamental in computer graphics, robotics and computer simulated environments. Most of the earlier work is restricted to either polyhedral models or static environments. In this paper, we present efficient algorithms for contact determination and interference detection between geometric models undergoing rigid motion. The set of models include polyhedra and surfaces described by algebraic sets or piecewise algebraic functions. The algorithms make use of temporal and spatial coherence between successive instances and their running time is a function of the motion between successive instances. The main characteristics of these algorithms are their simplicity and efficiency. They have been implemented; their performance on many applications indicates their potential for realtime simulations.
Virtual and Real Object Collisions in a Merged Environment
 Virtual Reality Software & Technology (Proc. VRST '94
, 1994
"... Seethrough headmounted display capability is becoming an important part of Virtual Environment applications. In such applications, it may be desirable to model the physical behavior of the virtual objects and their interaction with the real objects. This paper describes a software system which ..."
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Cited by 9 (0 self)
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Seethrough headmounted display capability is becoming an important part of Virtual Environment applications. In such applications, it may be desirable to model the physical behavior of the virtual objects and their interaction with the real objects. This paper describes a software system which integrates interactive collision detection, collision response and seethrough headmounted displays. The system employs a static model of the real world environment and allows for arbitrary convex virtual objects to be placed in the environment. The user may control the positions and velocities of the virtual objects. An approximately constant time collision detection algorithm and a Newtonian Mechanics based single point contact collision response is used to model the apparent physical interaction of the virtual and real objects for moderately complex environments. Keywords: Virtual Reality, Seethrough HeadMounted Displays, Collision Detection, Dynamics, Parallel. 1. Introduction...
A RealTime Algorithm for Accurate Collision Detection for Deformable Polyhedral Objects
 Presence
, 1998
"... We propose an accurate collision detection algorithm for use in virtual reality applications. The algorithm works for threedimensional graphical environments where multiple objects, represented as polyhedra (boundary representation), are undergoing arbitrary motion (translation and rotation). The a ..."
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Cited by 8 (1 self)
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We propose an accurate collision detection algorithm for use in virtual reality applications. The algorithm works for threedimensional graphical environments where multiple objects, represented as polyhedra (boundary representation), are undergoing arbitrary motion (translation and rotation). The algorithm can be used directly for both convex and concave objects and objects can be deformed (nonrigid) during motion. The algorithm works efficiently by first reducing the number of face pairs that need to be checked accurately for interference, by first localizing possible collision regions using bounding box and spatial subdivision techniques. Face pairs that remain after this pruning stage are then accurately checked for interference. The algorithm is efficient, simple to implement, and does not require any memoryintensive auxiliary data structures to be precomputed and updated. The performance of the proposed algorithm is compared directly against other existing algorithms, e.g., the separating plane algorithm, octree update method, and distancebased method. Results are given to show the efficiency of the proposed method in a general environment. 1
Interactive and Exact Collision Detection for LargeScaled Environments
 ACM SIGGRAPH
, 1994
"... : We present algorithms for exact collision detection in interactive environments. Such environments are characterized by the number of objects undergoing motion and the complexity of the models. We do not assume that the motions of the objects are expressible as closedform functions of time, nor d ..."
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Cited by 7 (1 self)
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: We present algorithms for exact collision detection in interactive environments. Such environments are characterized by the number of objects undergoing motion and the complexity of the models. We do not assume that the motions of the objects are expressible as closedform functions of time, nor do we assume any limitations on their velocities. The algorithms use a twolevel hierarchical representation for each model to selectively compute the precise contact between objects, achieving realtime performance without compromising accuracy. In large environments with n moving objects, they use the temporal and geometric coherence that exists between successive frames to overcome the bottleneck of O(n 2 ) pairwise comparisons. The algorithms have been successfully demonstrated in architectural walkthrough and simulated environments. In particular, the algorithm takes less than 1=20 of a second to determine all the collisions and contacts in environment consisting of more than 1000 movi...
From Virtual World to Reality: Designing an Autonomous Underwater Robot
 Proceedings of the IEEE Oceanic Engineering Society Conference OCEANS 92, Newport Rhode Island
, 1992
"... Design of autonomous underwater robots is particularly difficult due to the physical and sensor challenges of the underwater environment. Inaccessibility during operation and low probability of failure recovery makes robot stability and reliability paramount. Building an accurate and complete virtua ..."
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Cited by 4 (4 self)
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Design of autonomous underwater robots is particularly difficult due to the physical and sensor challenges of the underwater environment. Inaccessibility during operation and low probability of failure recovery makes robot stability and reliability paramount. Building an accurate and complete virtual world simulation is proposed as a necessary prerequisite for design of an autonomous underwater robot. A virtual world can include actual robot components and models for all other aspects of the world. Robot design can be fully tested using a virtual world and then verified using the real world. Additional testing can be performed in the virtual world that is not feasible in the real world. Visualization of robot interactions within a virtual world permits sophisticated analysis of robot performance that is otherwise unavailable. All aspects of world modeling and robot design must be mastered and coordinated in order to build an authentic virtual world and capable autonomous robot. 1 Prob...