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119
Fast continuous collision detection between rigid bodies
 Proc. of Eurographics (Computer Graphics Forum
, 2002
"... This paper introduces a fast continuous collision detection technique for polyhedral rigid bodies. As opposed to most collision detection techniques, the computation of the first contact time between two objects is inherently part of the algorithm. The method can thus robustly prevent objects interp ..."
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Cited by 49 (10 self)
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This paper introduces a fast continuous collision detection technique for polyhedral rigid bodies. As opposed to most collision detection techniques, the computation of the first contact time between two objects is inherently part of the algorithm. The method can thus robustly prevent objects interpenetrations or collisions misses, even when objects are thin or have large velocities. The method is valid for general objects (polygon soups), handles multiple moving objects and acyclic articulated bodies, and is efficient in low and high coherency situations. Moreover, the method can be used to speed up existent continuous collision detection methods for parametric or implicit rigid surfaces. The collision detection algorithms have been successfully coupled to a realtime dynamics simulator. Various experiments are conducted that show the method’s ability to produce highquality interaction (precise objects positioning for example) between models up to tens of thousands of triangles, which couldn’t have been performed with previous continuous methods. Categories and Subject Descriptors (according to ACM CCS): I.3.7 [Computer Graphics]: Animation Virtual Reality 1.
Collisions and Perception
 ACM Transactions on Graphics
, 2001
"... Level of Detail (LoD) techniques for realtime... In this paper, we are particularly interested in the problem of realistic collision simulation in scenes where large numbers of objects are colliding and processing must occur in realtime. An interruptible and therefore degradable collision handling ..."
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Cited by 46 (4 self)
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Level of Detail (LoD) techniques for realtime... In this paper, we are particularly interested in the problem of realistic collision simulation in scenes where large numbers of objects are colliding and processing must occur in realtime. An interruptible and therefore degradable collision handling mechanism is used and the perceptual impact of this degradation is explored. We look for ways in which we can optimise the realism of such simulations and describe a series of psychophysical experiments that investigated different factors affecting collision perception, including eccentricity, separation, distractors, causality and accuracy of physical response. Finally, strategies for incorporating these factors into a perceptually adaptive realtime simulation of large numbers of visually similar objects are presented.
Raising Roofs, Crashing Cycles, and Playing Pool: Applications of a Data Structure for Finding Pairwise Interactions
 In Proc. 14th Annu. ACM Sympos. Comput. Geom
, 1998
"... The straight skeleton of a polygon is a variant of the medial axis, introduced by Aichholzer et al., defined by a shrinking process in which each edge of the polygon moves inward at a fixed rate. We construct the straight skeleton of an ngon with r reflex vertices in time O(n 1+" +n 8=11+" r ..."
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Cited by 46 (0 self)
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The straight skeleton of a polygon is a variant of the medial axis, introduced by Aichholzer et al., defined by a shrinking process in which each edge of the polygon moves inward at a fixed rate. We construct the straight skeleton of an ngon with r reflex vertices in time O(n 1+" +n 8=11+" r 9=11+" ), for any fixed " ? 0, improving the previous best upper bound of O(nr log n). Our algorithm simulates the sequence of collisions between edges and vertices during the shrinking process, using a technique of Eppstein for maintaining extrema of binary functions to reduce the problem of finding successive interactions to two dynamic range query problems: (1) maintain a changing set of triangles in IR 3 and answer queries asking which triangle would be first hit by a query ray, and (2) maintain a changing set of rays in IR 3 and answer queries asking for the lowest intersection of any ray with a query triangle. We also exploit a novel characterization of the straight skeleton as a ...
Efficient PointBased Rendering Techniques for Haptic Display of Virtual Objects
 Presence
, 1999
"... Computer haptics, an emerging field of research that is analogous to computer graphics, is concerned with the generation and rendering of haptic virtual objects. In this paper, we propose an efficient haptic rendering method for displaying the feel of 3D polyhedral objects in virtual environments ( ..."
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Cited by 45 (5 self)
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Computer haptics, an emerging field of research that is analogous to computer graphics, is concerned with the generation and rendering of haptic virtual objects. In this paper, we propose an efficient haptic rendering method for displaying the feel of 3D polyhedral objects in virtual environments (VEs). Using this method and a haptic interface device, the users can manually explore and feel the shape and surface details of virtual objects. The main component of our rendering method is the "neighborhood watch" algorithm that takes advantage of precomputed connectivity information for detecting collisions between the end effector of a forcereflecting robot and polyhedral objects in VEs. We use a hierarchical database, multithreading techniques, and efficient search procedures to reduce the computational time such that the haptic servo rate after the first contact is essentially independent of the number of polygons that represent the object. We also propose efficient methods for displaying surface properties of objects such as haptic texture and friction. Our haptictexturing techniques and friction model can add surface details onto convex or concave 3D polygonal surfaces. These hapticrendering techniques can be extended to display dynamics of rigid and deformable objects. 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 44 (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 ...
Sensation Preserving Simplification for Haptic Rendering
, 2003
"... We introduce a novel "sensation preserving" simplification algorithm for faster collision queries between two polyhedral objects in haptic rendering. Given a polyhedral model, we construct a multiresolution hierarchy using "filtered edge collapse", subject to constraints imposed by collision detecti ..."
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Cited by 40 (13 self)
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We introduce a novel "sensation preserving" simplification algorithm for faster collision queries between two polyhedral objects in haptic rendering. Given a polyhedral model, we construct a multiresolution hierarchy using "filtered edge collapse", subject to constraints imposed by collision detection. The resulting hierarchy is then used to compute fast contact response for haptic display. The computation model is inspired by human tactual perception of contact information. We have successfully applied and demonstrated the algorithm on a timecritical collision query framework for haptically displaying complex objectobject interaction. Compared to existing exact contact query algorithms, we observe noticeable performance improvement in update rates with little degradation in the haptic perception of contacts.
Collision Detection for Continuously Deforming Bodies
, 2001
"... Fast and accurate collision detection between geometric bodies is essential in application areas like virtual reality, animation, simulation, games and robotics. In this work, we address the collision detection problem in applications where deformable bodies are used, which change their overall sh ..."
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Cited by 38 (0 self)
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Fast and accurate collision detection between geometric bodies is essential in application areas like virtual reality, animation, simulation, games and robotics. In this work, we address the collision detection problem in applications where deformable bodies are used, which change their overall shape every time step of the simulation. We propose and evaluate suitable bounding volume trees for deforming bodies that can be prebuilt and then updated very efficiently during simulation. Several heuristics for updating the trees due to deformations are compared to each other. By combining a topdown and a bottomup update strategy into a hybrid tree update method, promising results were achieved. Experiments show that our approach is four to five times faster than a previously leading method.
Virtual Environments for Medical Training: Graphical and Haptic Simulation of Laparoscopic Common Bile Duct Exploration
 IEEE/ASME Transactions on Mechatronics
, 2001
"... We have developed a computerbased training system to simulate laparoscopic procedures in virtual environments (VEs) for medical training. The major hardware components of our system include a computer monitor to display visual interactions between threedimensional (3D) virtual models of organs a ..."
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Cited by 36 (7 self)
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We have developed a computerbased training system to simulate laparoscopic procedures in virtual environments (VEs) for medical training. The major hardware components of our system include a computer monitor to display visual interactions between threedimensional (3D) virtual models of organs and instruments together with a pair of force feedback devices interfaced with laparoscopic instruments to simulate haptic interactions. In order to demonstrate the practical utility of the training system, we have chosen to simulate a surgical procedure that involves inserting a catheter into the cystic duct using a pair of laparoscopic forceps. This procedure is performed during laparoscopic cholecystectomy (gallbladder removal) to search for gallstones in the common bile duct. Using the proposed system, the user can be trained to grasp and insert a flexible and freely moving catheter into the deformable cystic duct in virtual environments. As the catheter and the duct are manipulated via s...
RECODE: An ImageBased Collision Detection Algorithm
 Proceedings of Pacific Graphics ’98
, 1998
"... Object interactions are ubiquitous in interactive computer graphics, 3D object motion simulations, virtual reality and robotics applications. Most collision detection algorithms are based on geometrical object–space interference tests. Some algorithms have employed an image– space approach to the co ..."
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Cited by 36 (0 self)
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Object interactions are ubiquitous in interactive computer graphics, 3D object motion simulations, virtual reality and robotics applications. Most collision detection algorithms are based on geometrical object–space interference tests. Some algorithms have employed an image– space approach to the collision detection problem. In this article, we demonstrate an image–space collision detection process that allows substatial computational savings during the image–space interference test. This approach makes efficient use of the graphics rendering hardware for real–time complex object interactions.
Fast Penetration Depth Computation for Physicallybased Animation
 of ETRI, FUB and UH on core experiment N2 on automatic segmentation of moving objects”. Doc. ISO/IEC JTC1/SC29/WG11 MPEG97/m2383
, 2002
"... We present a novel and fast algorithm to compute penetration depth (PD) between two polyhedral models for physicallybased animation. Given two overlapping polyhedra, it computes the minimal translation distance to separate them using a combination of objectspace and imagespace techniques. The alg ..."
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Cited by 35 (10 self)
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We present a novel and fast algorithm to compute penetration depth (PD) between two polyhedral models for physicallybased animation. Given two overlapping polyhedra, it computes the minimal translation distance to separate them using a combination of objectspace and imagespace techniques. The algorithm computes pairwise Minkowski sums of decomposed convex pieces and performs a closest point query using rasterization hardware. It uses bounding volume hierarchies, objectspace and imagespace culling algorithms to further accelerate the computation and refines the estimated PD in a hierarchical manner. We demonstrate its application to contact response computation and a timestepping method for dynamic simulation.