Results 1  10
of
189
Path Planning Using Lazy PRM
 In IEEE Int. Conf. Robot. & Autom
, 2000
"... This paper describes a new approach to probabilistic roadmap planners (PRMs). The overall theme of the algorithm, called Lazy PRM, is to minimize the number of collision checks performed during planning and hence minimize the running time of the planner. Our algorithm builds a roadmap in the configu ..."
Abstract

Cited by 243 (20 self)
 Add to MetaCart
(Show Context)
This paper describes a new approach to probabilistic roadmap planners (PRMs). The overall theme of the algorithm, called Lazy PRM, is to minimize the number of collision checks performed during planning and hence minimize the running time of the planner. Our algorithm builds a roadmap in the configuration space, whose nodes are the userdefined initial and goal configurations and a number of randomly generated nodes. Neighboring nodes are connected by edges representing paths between the nodes. In contrast with PRMs, our planner initially assumes that all nodes and edges in the roadmap are collisionfree, and searches the roadmap at hand for a shortest path between the initial and the goal node. The nodes and edges along the path are then checked for collision. If a collision with the obstacles occurs, the corresponding nodes and edges are removed from the roadmap. Our planner either finds a new shortest path, or first updates the roadmap with new nodes and edges, and then searches for a shortest path. The above process is repeated until a collisionfree path is returned.
Approximating Polyhedra with Spheres for TimeCritical Collision Detection
 ACM Transactions on Graphics
, 1996
"... This paper presents a method for approximating polyhedral objects to support a timecritical collisiondetection algorithm. The approximations are hierarchies of spheres, and they allow the timecritical algorithm to progressively refine the accuracy of its detection, stopping as needed to maintain ..."
Abstract

Cited by 212 (1 self)
 Add to MetaCart
(Show Context)
This paper presents a method for approximating polyhedral objects to support a timecritical collisiondetection algorithm. The approximations are hierarchies of spheres, and they allow the timecritical algorithm to progressively refine the accuracy of its detection, stopping as needed to maintain the realtime performance essential for interactive applications. The key to this approach is a preprocess that automatically builds tightly fitting hierarchies for rigid and articulated objects. The preprocess uses medialaxis surfaces, which are skeletal representations of objects. These skeletons guide an optimization technique that gives the hierarchies accuracy properties appropriate for collision detection. In a sample application, hierarchies built this way allow the timecritical collisiondetection algorithm to have acceptable accuracy, improving significantly on that possible with hierarchies built by previous techniques. The performance of the timecritical algorithm in this appli...
Collision detection for interactive graphics applications
 IEEE Trans. on Visualization and Computer Graphics
, 1995
"... ..."
(Show Context)
The Haptic Display of Complex Graphical Environments
 PROC. OF ACM SIGGRAPH
, 1997
"... Force feedback coupled with visual display allows people to interact intuitively with complex virtual environments. For this synergy of haptics and graphics to flourish, however, haptic systems must be capable of modeling environments with the same richness, complexity and interactivity that can be ..."
Abstract

Cited by 206 (10 self)
 Add to MetaCart
(Show Context)
Force feedback coupled with visual display allows people to interact intuitively with complex virtual environments. For this synergy of haptics and graphics to flourish, however, haptic systems must be capable of modeling environments with the same richness, complexity and interactivity that can be found in existing graphic systems. To help meet this challenge, we have developed a haptic rendering system that allows for the efficient tactile display of graphical information. The system uses a common highlevel framework to model contact constraints, surface shading, friction and texture. The multilevel control system also helps ensure that the haptic device will remain stable even as the limits of the renderer's capabilities are reached.
On Finding Narrow Passages with Probabilistic Roadmap Planners
, 1998
"... ... This paper provides foundations for understanding the effect of passages on the connectedness of probabilistic roadmaps. It also proposes a new random sampling scheme for finding such passages. An initial roadmap is built in a "dilated" free space allowing some penetration distance of ..."
Abstract

Cited by 181 (31 self)
 Add to MetaCart
... This paper provides foundations for understanding the effect of passages on the connectedness of probabilistic roadmaps. It also proposes a new random sampling scheme for finding such passages. An initial roadmap is built in a "dilated" free space allowing some penetration distance of the robot into the obstacles. This roadmap is then modified by resampling around the links that do not lie in the true free space. Experiments show that this strategy allows relatively small roadmaps to reliably capture the free space connectivity
Impulsebased Simulation of Rigid Bodies
, 1995
"... We introduce a promising new approach to rigid body dynamic simulation called impulsebased simulation. The method is well suited to modeling physical systems with large numbers of collisions, or with contact modes that change frequently. All types of contact (colliding, rolling, sliding, and restin ..."
Abstract

Cited by 178 (10 self)
 Add to MetaCart
We introduce a promising new approach to rigid body dynamic simulation called impulsebased simulation. The method is well suited to modeling physical systems with large numbers of collisions, or with contact modes that change frequently. All types of contact (colliding, rolling, sliding, and resting) are modeled through a series of collision impulses between the objects in contact, hence the method is simpler and faster than constraintbased simulation. We have implemented an impulsebased simulator that can currently achieve interactive simulation times, and real time simulation seems within reach. In addition, the simulator has produced physically accurate results in several qualitative and quantitative experiments. After giving an overview of impulsebased dynamic simulation, we discuss collision detection and collision response in this context, and present
Enhancing GJK: Computing Minimum and Penetration Distances between Convex Polyhedra
 Proceedings of International Conference on Robotics and Automation
, 1997
"... The problem of tracking the distance between two convex polyhedra is finding applications in many areas of robotics, including intersection detection, collision detection, and path planning. We present new results that confirm an almostconstant time complexity for an enhanced version of Gilbert, Jo ..."
Abstract

Cited by 138 (5 self)
 Add to MetaCart
(Show Context)
The problem of tracking the distance between two convex polyhedra is finding applications in many areas of robotics, including intersection detection, collision detection, and path planning. We present new results that confirm an almostconstant time complexity for an enhanced version of Gilbert, Johnson and Keerthi's algorithm, and also describe modifications to the algorithm to compute measures of penetration distance.
3D Collision Detection: A Survey
 Computers and Graphics
, 2000
"... Many applications in Computer Graphics require fast and robust 3D collision detection algorithms. These algorithms can be grouped into four approaches: spacetime volume intersection, swept volume interference, multiple interference detection and trajectory parameterization. While some approaches ar ..."
Abstract

Cited by 127 (4 self)
 Add to MetaCart
Many applications in Computer Graphics require fast and robust 3D collision detection algorithms. These algorithms can be grouped into four approaches: spacetime volume intersection, swept volume interference, multiple interference detection and trajectory parameterization. While some approaches are linked to a particular object representation scheme (e.g., spacetime volume intersection is particularly suited to a CSG representation), others do not. The multiple interference detection approach has been the most widely used under a variety of sampling strategies, reducing the collision detection problem to multiple calls to static interference tests. In most cases, these tests boil down to detecting intersections between simple geometric entities, such as spheres, boxes aligned with the coordinate axes, or polygons and segments. The computational cost of a collision detection algorithm depends not only on the complexity of the basic interference test used, but also on the ...
On Delaying Collision Checking in PRM Planning  Application To MultiRobot Coordination
 INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH
, 2002
"... This paper describes the foundations and algorithms of a new probabilistic roadmap (PRM) planner that is: singlequery  instead of precomputing a roadmap covering the entire free space, it uses the two input query configurations to explore as little space as possible; bidirectional  it explo ..."
Abstract

Cited by 81 (15 self)
 Add to MetaCart
This paper describes the foundations and algorithms of a new probabilistic roadmap (PRM) planner that is: singlequery  instead of precomputing a roadmap covering the entire free space, it uses the two input query configurations to explore as little space as possible; bidirectional  it explores the robot's free space by building a roadmap made of two trees rooted at the query configurations; and lazy in checking collisions  it delays collision tests along the edges of the roadmap until they are absolutely needed. Several observations motivated this strategy: (1) PRM planners spend a large fraction of their time testing connections for collision; (2) most connections in a roadmap are not on the final path; (3) the collision test for a connection is most expensive when there is no collision; and (4) any short connection between two collisionfree configurations has high prior probability of being collisionfree. The strengths of singlequery and bidirectional sampling techniques, and those of delayed collision checking reinforce each other. Experimental results