Broad Phase Collision Detection Research Articles

Efficient collision detection using hybrid medial axis transform and BVH for rigid body simulation

Medial Axis Transform (MAT) has been recently adopted as the acceleration structure of broad-phase collision detection. Compared to traditional BVH-based methods, MAT can provide a high-fidelity volumetric approximation of 3D complex objects, resulting in higher collision culling efficiency. However, due to MAT’s non-hierarchical structure, it may be outperformed in collision-light scenarios because several cullings at the top level of a BVH may take a large number of cullings with MAT. We propose a collision detection method that combines MAT and BVH to address the above problem. Our technique efficiently culls collisions between dynamic and static objects. Experimental results show that our method has higher culling efficiency than pure BVH or MAT methods.

A Fast and Generalized Broad-Phase Collision Detection Method Based on KD-Tree Spatial Subdivision and Sweep-and-Prune

Various graphics applications use multibody collision detection, a critical technology in computer graphics, system simulations, and virtual reality. In these simulation environments, broad-phase collision detection, as part of collision detection, plays a critical role in ensuring that rejecting disjoint objects and collision detection is accelerated. Few existing methods implement collision detection of millions of objects in a general-purpose environment on the CPU. This paper proposes a broad-phase collision detection algorithm based on KD-Tree spatial subdivision and sweep-and-prune, which optimizes and accelerates broad-phase collision detection using a pre-sorting and temporal inference solution. Our method enables broad-phase collision detection for coherent and non-coherent settings for uniformly and non-uniformly sized objects respectively. Based on our proposed solution is tested in the context of complex scenarios and compared with other solutions available in the literature and in the industry. The experimental results show that our approach has a 1X to 2X performance improvement in virtual environments with up to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1024 \times 10^{3}$ </tex-math></inline-formula> objects, reaching the fastest collision detection speed of 119.45 milliseconds per frame in the test environment.

Analysis of parallel spatial partitioning algorithms for GPU based DEM

Abstract The capability of solving a geotechnical discrete element method (DEM) applications is determined by the complexity of the simulation and its computational requirements. Collision detection algorithms are fundamental to resolve the mechanical collisions between millions of particles efficiently. These algorithms are a bottleneck for many DEM applications resulting in excessive memory usage or poor computational performance. In particular, for GPU based DEM, there are many factors for a user to consider when deciding on an algorithm. This study discusses a set of diverse classes of geotechnical problems and the impact of algorithm choice. Four factors were considered: i) the world domain size, number of particles and particle density, ii) polydispersity in size, iii) the time evolution and iv) the particle shape. This study shows that for spherical particles, the choice of broad-phase collision detection algorithm has the most impact on computational performance. The computational cost for convex polyhedral particles is dominated by the selection of the particles’ bounding volumes and their intersection tests over the selection of the broad-phase collision detection algorithm. On average for convex polyhedral particles, the broad-phase occupies at most 1.3% of the total runtime, while the narrow-phase collision detection and collision response require more than 87% of the runtime. A combination of bounding spheres and axis-aligned bounding boxes for use as bounding volumes of particles showed the best performance reducing the computational cost by 20%. This study serves as a guide for further research in the field of GPU based DEM collision detection and the application in geotechnics.

Adaptive Collision Culling for Massive Simulations by a Parallel and Context-Aware Sweep and Prune Algorithm.

We present an improved parallel Sweep and Prune algorithm that solves the dynamic box intersection problem in three dimensions. It scales up to very large datasets, which makes it suitable for broad phase collision detection in complex moving body simulations. Our algorithm gracefully handles high-density scenarios, including challenging clustering behavior, by using a double-axis sweeping approach and a cache-friendly succinct data structure. The algorithm is realized by three parallel stages for sorting, candidate generation, and object pairing. By the use of temporal coherence, our sorting stage runs with close to optimal load balancing. Furthermore, our approach is characterized by a work-division strategy that relies on adaptive partitioning, which leads to almost ideal scalability. In addition, for scenarios that involves intense clustering along several axes simultaneously, we propose an enhancement that increases the context-awareness of the algorithm. By exploiting information gathered along three orthogonal axes, an efficient choice of what range query to perform can be made per object during run-time. Experimental results show high performance for up to millions of objects on modern multi-core CPUs.

A hybrid fixed-function and microprocessor solution for high-throughput broad-phase collision detection

We present a hybrid system spanning a fixed-function microarchitecture and a general-purpose microprocessor, designed to amplify the throughput and decrease the power dissipation of collision detection relative to what can be achieved using CPUs or GPUs alone. The primary component is one of the two novel microarchitectures designed to perform the principal elements of broad-phase collision detection. Both microarchitectures consist of pipelines comprising a plurality of memories, which rearrange the input into a format that maximises parallelism and bandwidth. The two microarchitectures are combined with the remainder of the system through an original method for sharing data between a ray tracer and the collision-detection microarchitectures to minimise data structure construction costs. We effectively demonstrate our system using several benchmarks of varying object counts. These benchmarks reveal that, for over one million objects, our design achieves an acceleration of 812 × relative to a CPU and an acceleration of 161 × relative to a GPU. We also achieve energy efficiencies that enable the mitigation of silicon power-density challenges, while making the design amenable to both mobile and wearable computing devices.

SPHERE ENCAPSULATED ORIENTED-DISCRETE ORIENTATION POLYTOPES (S-DOP) COLLISION CULLING FOR MULTI-, RIGID BODY DYNAMIC

This paper discusses on sphere encapsulated oriented-discrete orientation polytopes (therefore will be referred to as S-Dop) collision culling for multiple rigid body simulation. In order to improve performance of the whole simulation system, there are available options in sacrificing the accuracy over speed by using certain approximation techniques. The aim of this research is to achieve excellent performance through implementation of suitable culling technique, without jeopardizing the resulting behavior so that the simulation will still be physically plausible. The basic idea is to identify the highly probable pairs to collide and test the pair with a more accurate collision test in broad-phase collision detection, before the pair is passed to a more costly stage. Results from the experiments showed that there are a number of ways to implement the sphere encapsulated or-Dops (S-Dop) collision culling on a multiple rigid body simulation depending on the level of performance needed.

Performance of a Method for Formulating Geometrically Exact Complementarity Constraints in Multibody Dynamic Simulation

Contemporary problem formulation methods used in the dynamic simulation of rigid bodies suffer from problems in accuracy, performance, and robustness. Significant allowances for parameter tuning, coupled with careful implementation of a broad-phase collision detection scheme are required to make dynamic simulation useful for practical applications. A constraint formulation method is presented herein that is more robust, and not dependent on broad-phase collision detection or system tuning for its behavior. Several uncomplicated benchmark examples are presented to give an analysis and make a comparison of the new polyhedral exact geometry (PEG) method with the well-known Stewart–Trinkle method. The behavior and performance for the two methods are discussed. This includes specific cases where contemporary methods fail to match theorized and observed system states in simulation, and how they are ameliorated by the new method presented here. The goal of this work is to complete the groundwork for further research into high performance simulation.

705 GPUを利用した高速な立体間の干渉検出技術(OS7 オーガナイズドセッション《精密/微細加工と評価》)

In this paper, a new GPU based algorithm is proposed for detecting collisions between solid objects. The proposed algorithm is fast, precise, and applicable to large and complex objects with huge number of polygons. In our broad phase collision detection, a culling program based on the lattice structure is executed on GPU to efficiently exclude apparently non-colliding polygons. In the following narrow phase collision detection, parallel processing capability of GPU is used for detecting mutually penetrating polygons. A sample program is implemented and tested with complex examples.

Accelerating physics in large, continuous virtual environments

SUMMARYLarge virtual environments with many interactive objects pose high processing overhead for physics simulation and require real‐time results. Most of these objects are not being interacted with at the same time, leaving many in physical equilibrium. Modern physics simulation software eliminates some work for the case of objects at rest, but these objects still pose overhead because of potential activation during processing, which can constitute the majority of running time for some environments. We present a physics software design that eliminates overhead associated with bodies at rest, reducing the remaining running time to be proportional to the number of objects being interacted with. Our design consists of specific broad phase collision detection, contact group generation, and object storage methods, as well as intermediate structures and interfacing methods within the physics pipeline. It can be combined with various narrow phase collision detection, constraint solving, and integration techniques, as well as methods of parallelism. We show that our system produces a running time independent of the number of objects at rest, and that our methods compare favorably with published methods and available physics software when simulating environments with many objects at rest. CR Categories: I.3.6 [Computer graphics]: Methodology and techniques—Graphics data structures and data types; I.3.7 [Computer graphics]: Three‐dimensional graphics and realism—virtual reality. Copyright © 2011 John Wiley &amp; Sons, Ltd.

A Hierarchical Hashing Scheme for Nearest Neighbor Search and Broad-Phase Collision Detection

Increasing computational power allows computer graphics researchers to model spectacular phenomena such as fluids and their interactions with deformable objects and structures. Particle-based (or Lagrangian) fluid and solid simulations are commonly managed separately and mixed together for the collision detection phase. We present a unified dynamic acceleration model to be used for particle neighborhood queries and broad-phase collision detection, based on a hierarchical hash table data structure. Our method is able to significantly reduce computations in large, empty areas, and thus gives better results than existing acceleration techniques, such as multilevel hashing schemes or KD-trees, in most situations.