GPU Ray-Traced Collision Detection Fine Pipeline Reorganization

Total Page:16

File Type:pdf, Size:1020Kb

GPU Ray-Traced Collision Detection Fine Pipeline Reorganization GPU Ray-traced Collision Detection Fine Pipeline Reorganization Franc¸ois Lehericey, Valerie´ Gouranton and Bruno Arnaldi INSA de Rennes, IRISA, Inria, Campus de Beaulieu, 35042 Rennes cedex, France Keywords: Collision Detection, Narrow-phase, GPU Computing. Abstract: Ray-tracing algorithms can be used to render a virtual scene and to detect collisions between objects. Numer- ous ray-tracing algorithms have been proposed which use data structures optimized for specific cases (rigid objects, deformable objects, etc.). Some solutions try to optimize performance by combining several algo- rithms to use the most efficient algorithm for each ray. This paper presents a ray-traced collision detection pipeline that improves the performance on a graphicd processing unit (GPU) when several ray-tracing algo- rithms are used. When combining several ray-tracing algorithms on a GPU, a well-known drawback is thread divergence among work-groups that can cause loss of performance by causing idle threads. In this paper we avoid branch divergence by dividing the ray tracing into three steps with append buffers in between. We also show that prediction can be used to avoid unnecessary synchronizations between the CPU and GPU. Applied to a narrow-phase collision detection algorithm, results show an improvement of performance up to 2.7 times. 1 INTRODUCTION In the literature four categories of narrow-phase algorithms are studied, including image-based algo- Collision detection (CD) is an important task in vir- rithms that uses rendering techniques to detect colli- tual reality (VR). From a set of objects, we need to sions. As GPUs are designed especially for render- know those which collide. Nowadays collision is one ing, image-based methods are well suited for GPGPU of the main bottlenecks in VR applications due to the implementations. In particular ray-tracing algorithms complexity of environments we want to simulate and can be used and several ones can be combined the real-time constraint required by VR. We need to to improve performance (Lehericey et al., 2013a). simulate large environments that can count millions When implementing several ray-tracing algorithms of objects. And we want to include complex objects on GPUs, high branch divergence in the execution that can be deformable, undergo topology changes or can lead to underuse of the GPU and reduced perfor- be fluids. mance. To handle such a work load, collision is generally Main Contributions: we present a new pipeline or- divided into two phases: broad-phase and narrow- ganization of the narrow-phase for ray-traced colli- phase. The broad-phase takes the whole set of objects sion detection. The goal of our pipeline is to minimize from the environment and provides a set of pairs of thread divergence on GPUs to improve performance. objects that might collide. The narrow-phase takes Our pipeline is designed to be able to integrate sev- these pairs and outputs the ones that actually col- eral ray-tracing algorithms without causing overhead. lide. This paper focuses on the narrow-phase which We then present a prediction method to avoid CPU- is nowadays the most time-consuming phase. GPU synchronization between steps of the pipeline to Recent approaches use GPGPU (general-purpose further improve performance. computing on graphics processing units) to take ad- This paper is arranged as follows. The follow- vantage of the high computational power of recent ing section provides a reviex of the relevant literature. GPUs. Parallel implementation of the broad-phase Section 3 presents our ray-traced collision pipeline. sweep and prune algorithm on GPUs improve per- Section 4 shows how prediction can be used to avoid formance by orders of magnitude (Liu et al., 2010). unnecessary synchronization between the CPU and The narrow-phase can also be implemented on a GPU GPU. Implementation and results are discussed in (Pabst et al., 2010). Section 5. Section 6 concludes this paper. Lehericey F., Gouranton V. and Arnaldi B.. 317 GPU Ray-traced Collision Detection - Fine Pipeline Reorganization. DOI: 10.5220/0005299603170324 In Proceedings of the 10th International Conference on Computer Graphics Theory and Applications (GRAPP-2015), pages 317-324 ISBN: 978-989-758-087-1 Copyright c 2015 SCITEPRESS (Science and Technology Publications, Lda.) GRAPP2015-InternationalConferenceonComputerGraphicsTheoryandApplications 2 RELATED WORK gorithm is a fast ray-tracing algorithm that exploits spatial and temporal coherency by updating the previ- This section focuses on the literature on CD which is ous time-step. These algorithms can be used on GPUs most pertinent to our work, in particular image-based for improved performance. algorithms for the narrow-phase. For an exhaustive overview on CD, readers should refer to surveys such 2.2 GPU Computing as (Teschner et al., 2005; Kockara et al., 2007). Several methods consider the GPU as a streaming 2.1 Image-based Collision Detection processor. As GPUs are massively parallel proces- sors, computations should be arranged to be made parallel (Nickolls and Dally, 2010). Image-based algorithms use rendering techniques to When code runs on a GPU, the same function detect collisions. These methods are often adapted for (called kernel) is called by multiple threads (called GPUs, which are processors designed for rendering. work-item) on different data. Work-items do not run Image-based methods can be used to perform colli- independently but in a group (called work-group); in sion detection on rigid and deformable bodies. These a work-group, work-items run in a single instruction, techniques usually do not require any pre-processing multiple data way. On a conditional branch, if the steps which makes them suitable for dynamically de- work-items diverge among a work-group, each branch forming objects. Image-based algorithms can either runs serially. This phenomena is called thread diver- use rasterization or ray-tracing techniques. gence and reduces performance (Zhang et al., 2010). Rasterization can be used to compute a layered One case of thread divergence is having a sparse depth image (LDI) which can be post-processed to input, in which case some work-items have nothing to detect collisions (Allard et al., 2010). The CInDeR do and are idle in a work-group while the other work- algorithm (Knott, 2003) uses rasterization to implic- items finish. Collision-streams (Tang et al., 2011) itly cast rays from the edges of an object and counts use stream compaction to avoid kernel execution on how many object faces the ray passes through. If the sparse inputs. Collision detection is divided into sev- result is odd then there is collision; otherwise there is eral steps and streaming compaction is used between no collision. (Heidelberger et al., 2003; Heidelberger steps to ensure dense input for each kernel. et al., 2004) take three-dimensional closed objects and output the intersection volume without the needs of 2.3 Synthesis any data structures making it suitable for deformable objects. The main drawback of these techniques is the Ray-traced collision detection can be used on GPUs discretization of the space through rendering that in- to achieve high performance on complex scenes. In duces approximations and may lead to the omission a simple scenario only one ray-tracing algorithm can of small objects. be used to resolve collisions. But in complex scenes Ray-tracing algorithms can be used to overcome with objects of different nature we can employ sev- these approximations. (Wang et al., 2012) show that eral ray-tracing algorithms to optimize each nature of ray tracing can be used to compute a LDI with a object. With rigid objects we can use algorithms with higher resolution around small objects by increasing complex data structures. With deformable objects we the density or rays locally to increase the precision. need data structures that can be updated at each time- (Hermann et al., 2008) detect collisions by casting step. In the case of topology changes we need to re- rays from each vertex of the objects. Rays are cast construct the ray-tracing data structures occasionally. in the inward direction; the ones that hit another ob- Iterative ray-tracing can be used to accelerate all of ject before leaving the source object detect a collision. these algorithms. Before casting a ray, the ones that are outside the in- In complex scenes where all these properties tersection of the bonding volumes are dropped since are represented, combining several ray-tracing algo- they cannot collide. rithms improves performance. In such situations, the Based on Hermann et al.’s algorithm, (Lehericey need of a narrow-phase that can easily manage di- et al., 2013a; Lehericey et al., 2013b) introduced verse ray-tracing algorithms without losing perfor- an iterative ray-traced collision detection algorithm mance emerges. (IRTCD). This method combines two different ray- tracing algorithms; a full and an iterative algorithm that are respectively used for high and small displace- ments between objects. The full algorithm can be any existing ray-tracing algorithm. The iterative al- 318 GPURay-tracedCollisionDetection-FinePipelineReorganization 3 RAY-TRACED CD PIPELINE quentially. Second, in a context where we can safely cull some vertices to reduce the amount of compu- To perform our ray-traced CD method there are sev- tation, this naive implementation will initiate work- eral ray-tracing algorithms available in the literature. items that finish immediately. These work-items will We selected three algorithms. We qualify the two first then be idle while the other work-items of the work- ones as ‘full’ ray-tracing algorithms; these algorithms group finish. can be used at any time. The third algorithm, called This section presents our pipeline distribution of iterative, requires specific conditions. tasks to improve the performance of ray-traced col- The first full algorithm is a stackless bounding lision detection on GPUs. Subsection 3.1 gives an volume hierarchy (BVH) traversal.
Recommended publications
  • Tree Code for Collision Detection of Large Numbers of Particles
    Tree Code for Collision Detection of Large Numbers of Particles Application for the Breit-Wheeler Process [preprint] O. Jansen, E. d’Humi`eres, X. Ribeyre, S. Jequier, V.T. Tikhonchuk Univ. Bordeaux/CNRS/CEA, Centre Lasers Intenses et Applications [email protected] August 4, 2016 Abstract Collision detection of a large number N of particles can be challenging. Directly testing N particles for 2 collision among each other leads to N queries. Especially in scenarios, where fast, densely packed particles interact, challenges arise for classical methods like Particle-in-Cell or Monte-Carlo. Modern collision detec- tion methods utilising bounding volume hierarchies are suitable to overcome these challenges and allow a detailed analysis of the interaction of large number of particles. This approach is applied to the analysis of the collision of two photon beams leading to the creation of electron-positron pairs. Keywords tree code; collision detection; QED; Breit-Wheeler process; pair creation; astronomy 1 Introduction Modelling a large number of particles often is a challenge in physics. Many-body problems are well known in astronomy, plasma physics, solid state physics and other disciplines. In astronomy a common way to overcome the challenge of simulating a many-body problem, like the movement of stars of one galaxy under each others gravitational force, is to use the Barnes-Hut (BH) method [1]. In a BH simulation space is partitioned in an hierarchic octree structure. The tree branches grow towards successive smaller volumes of space in such way as to include at maximum one particle (star) in each leaf node, while still covering the entirety of the simulation domain.
    [Show full text]
  • Efficient Algorithms for Two-Phase Collision Detection
    MERL { A MITSUBISHI ELECTRIC RESEARCH LABORATORY http://www.merl.com Ecient Algorithms for Two-Phase Collision Detection Brian Mirtich TR-97-23 Decemb er 1997 Abstract This article describ es practical collision detection algorithms for rob ot motion planning. Attention is restricted to algorithms that handle rigid, p olyhedral ge- ometries. Both broad phase and narrow phase detection strategies are discussed. For the broad phase, an algorithm using axes-aligned b ounding b oxes and a hi- erarchical spatial hash table is describ ed. For the narrow-phase, the Lin-Canny algorithm is presented. Alternatives to these algorithms are also discussed. Fi- nally, the article describ es a scheduling paradigm for managing collision checks that can further reduce computation time. Pointers to downloadable software are included. To appear in Practical Motion Planning in Rob otics: Current Approaches and Future Directions, K. Gupta and A.P. del Pobil, editors. This work may not b e copied or repro duced in whole or in part for any commercial purp ose. Permission to copy in whole or in part without payment of fee is granted for nonpro t educational and research purp oses provided that all such whole or partial copies include the following: a notice that such copying is by p er- mission of Mitsubishi Electric Information Technology Center America; an acknowledgment of the authors and individual contributions to the work; and all applicable p ortions of the copyright notice. Copying, repro duction, or republishing for any other purp ose shall require a license with payment of fee to Mitsubishi Electric Information Technology Center America.
    [Show full text]
  • An Optimal Solution for Implementing a Specific 3D Web Application
    IT 16 060 Examensarbete 30 hp Augusti 2016 An optimal solution for implementing a specific 3D web application Mathias Nordin Institutionen för informationsteknologi Department of Information Technology Abstract An optimal solution for implementing a specific 3D web application Mathias Nordin Teknisk- naturvetenskaplig fakultet UTH-enheten WebGL equips web browsers with the ability to access graphic cards for extra processing Besöksadress: power. WebGL uses GLSL ES to communicate with graphics cards, which uses Ångströmlaboratoriet Lägerhyddsvägen 1 different Hus 4, Plan 0 instructions compared with common web development languages. In order to simplify the development process there are JavaScript libraries handles the Postadress: Box 536 751 21 Uppsala communication with WebGL. On the Khronos website there is a listing of 35 different Telefon: JavaScript libraries that access WebGL. 018 – 471 30 03 It is time consuming for developers to compare the benefits and disadvantages of all Telefax: these 018 – 471 30 00 libraries to find the best WebGL library for their need. This thesis sets up requirements of a Hemsida: specific WebGL application and investigates which libraries that are best for http://www.teknat.uu.se/student implmeneting its requirements. The procedure is done in different steps. Firstly is the requirements for the 3D web application defined. Then are all the libraries analyzed and mapped against these requirements. The two libraries that best fulfilled the requirments is Three.js with Physi.js and Babylon.js. The libraries is used in two seperate implementations of the intitial game. Three.js with Physi.js is the best libraries for implementig the requirements of the game.
    [Show full text]
  • Mathematical Approaches for Collision Detection in Fundamental Game Objects
    Mathematical Approaches for Collision Detection in Fundamental Game Objects Weihu Hong1 , Junfeng Qu2, Mingshen Wu3 1 Department of Mathematics, Clayton State University, Morrow, GA, 30260 2 Department of Information Technology, Clayton State University, Morrow, GA, 30260 3Department of Mathematics, Statistics, and Computer Science, University of Wisconsin-Stout, Menomonie, WI 54751 Otherwise, a lot of false alarm will be introduced in collision Abstract – This paper presents mathematical solutions for detection as show in Figure 1, where two objects, one circle computing whether or not fundamental objects in game and one pentagon, are not collided at all even the represented development collide with each other. In game development, sprites collide each other. detection of collision of two or more objects is often brought up. By categorizing most fundamental boundaries in game object, this paper will provide some mathematical fundamental methods for detection of collisions between objects identified. The approached methods provide more precise and efficient solutions to detect collisions between most game objects with mathematical formula proposed. Keywords: Collision detection, algorithm, sprite, game object, game development. 1 Introduction Figure 1. Collision detection based on Boundary The goal of collision detection is to automatically report a geometric contact when it is about to occur or has actually occurred. It is very common in game development that objects in the game science controlled by game player might collide each other. Collision detection is an essential component in video game implementation because it delivers events in the game world and drives game moving though game paths designed. In most game developing environment, game developers relies on written APIs to detect collisions in the game, for example, XNA Game Studio from Microsoft, Cocoa from (a) (b) Apple, and some other software packages developed by other parties.
    [Show full text]
  • Opencl Accelerated Rigid Body and Collision Detection
    OpenCL accelerated rigid body and collision detection Erwin Coumans Advanced Micro Devices Robotics: Science and Systems Conference 2011 Overview • Intro • GPU broadphase acceleration structures • GPU convex contact generation and reduction • GPU BVH acceleration for concave shapes • GPU constraint solver Robotics: Science and Systems Conference 2011 Industry view PS3, Xbox 360, x86, PowerPC, PC, iPhone, Android Havok, PhysX Cell, ARM Bullet, ODE, Newton, PhysBAM, Box2D OpenCL, CUDA Hardware Platform C++ APIs and Implementations Custom in-house Rockstar, Epic physics engines EA, Disney Games Industry Content Creation Maya, 3ds Max, Houdini, LW, Game and Film Tools Cinema 4D Sony Imageworks physics Simulation Movie Industry Blender Data PDI Dreamworks representation Academia, Universities Conferences, binary .hkx, ILM, Disney Presentations .bullet format Stanford, UNC FBX, COLLADA GDC, SIGGRAPH etc. Robotics: Science and Systems Conference 2011 Our open source work • Bullet Physics SDK, http://bulletphysics.org • Sony Computer Entertainment Physics Effects • OpenCL/DirectX11 GPU physics research Robotics: Science and Systems Conference 2011 OpenCL™ • Open development platform for multi-vendor heterogeneous architectures • The power of AMD Fusion: Leverages CPUs and GPUs for balanced system approach • Broad industry support: Created by architects from AMD, Apple, IBM, Intel, NVIDIA, Sony, etc. AMD is the first company to provide a complete OpenCL solution • Kernels written in subset of C99 Robotics: Science and Systems Conference 2011 Particle
    [Show full text]
  • Bounding Volume Hierarchies
    Simulation in Computer Graphics Bounding Volume Hierarchies Matthias Teschner Outline Introduction Bounding volumes BV Hierarchies of bounding volumes BVH Generation and update of BVs Design issues of BVHs Performance University of Freiburg – Computer Science Department – 2 Motivation Detection of interpenetrating objects Object representations in simulation environments do not consider impenetrability Aspects Polygonal, non-polygonal surface Convex, non-convex Rigid, deformable Collision information University of Freiburg – Computer Science Department – 3 Example Collision detection is an essential part of physically realistic dynamic simulations In each time step Detect collisions Resolve collisions [UNC, Univ of Iowa] Compute dynamics University of Freiburg – Computer Science Department – 4 Outline Introduction Bounding volumes BV Hierarchies of bounding volumes BVH Generation and update of BVs Design issues of BVHs Performance University of Freiburg – Computer Science Department – 5 Motivation Collision detection for polygonal models is in Simple bounding volumes – encapsulating geometrically complex objects – can accelerate the detection of collisions No overlapping bounding volumes Overlapping bounding volumes → No collision → Objects could interfere University of Freiburg – Computer Science Department – 6 Examples and Characteristics Discrete- Axis-aligned Oriented Sphere orientation bounding box bounding box polytope Desired characteristics Efficient intersection test, memory efficient Efficient generation
    [Show full text]
  • Efficient Collision Detection Using Bounding Volume Hierarchies of K
    Efficient Collision Detection Using Bounding Volume £ Hierarchies of k -DOPs Þ Ü ß James T. Klosowski Ý Martin Held Joseph S.B. Mitchell Henry Sowizral Karel Zikan k Abstract – Collision detection is of paramount importance for many applications in computer graphics and visual- ization. Typically, the input to a collision detection algorithm is a large number of geometric objects comprising an environment, together with a set of objects moving within the environment. In addition to determining accurately the contacts that occur between pairs of objects, one needs also to do so at real-time rates. Applications such as haptic force-feedback can require over 1000 collision queries per second. In this paper, we develop and analyze a method, based on bounding-volume hierarchies, for efficient collision detection for objects moving within highly complex environments. Our choice of bounding volume is to use a “discrete orientation polytope” (“k -dop”), a convex polytope whose facets are determined by halfspaces whose outward normals come from a small fixed set of k orientations. We compare a variety of methods for constructing hierarchies (“BV- k trees”) of bounding k -dops. Further, we propose algorithms for maintaining an effective BV-tree of -dops for moving objects, as they rotate, and for performing fast collision detection using BV-trees of the moving objects and of the environment. Our algorithms have been implemented and tested. We provide experimental evidence showing that our approach yields substantially faster collision detection than previous methods. Index Terms – Collision detection, intersection searching, bounding volume hierarchies, discrete orientation poly- topes, bounding boxes, virtual reality, virtual environments.
    [Show full text]
  • A New Fast and Robust Collision Detection and Force Computation Algorithm Applied to the Physics Engine Bullet: Method, Integration, and Evaluation
    Conference and Exhibition of the European Association of Virtual and Augmented Reality (2014) G. Zachmann, J. Perret, and A. Amditis (Editors) A New Fast and Robust Collision Detection and Force Computation Algorithm Applied to the Physics Engine Bullet: Method, Integration, and Evaluation Mikel Sagardia †, Theodoros Stouraitis‡, and João Lopes e Silva§ German Aerospace Center (DLR), Institute of Robotics and Mechatronics, Germany Abstract We present a collision detection and force computation algorithm based on the Voxelmap-Pointshell Algorithm which was integrated and evaluated in the physics engine Bullet. Our algorithm uses signed distance fields and point-sphere trees and it is able to compute collision forces between arbitrary complex shapes at simulation frequencies smaller than 1 msec. Utilizing sphere hierarchies, we are able to rapidly detect likely colliding areas, while the point trees can be used for processing colliding regions in a level-of-detail manner. The integration into the physics engine Bullet was performed inheriting interface classes provided in that framework. We compared our algorithm with Bullet’s native GJK, GJK with convex decomposition, and GImpact, varying the resolution and the scenarios. Our experiments show that our integrated algorithm performs with similar computation times as the standard collision detection algorithms in Bullet if low resolutions are chosen. With high resolutions, our algorithm outperforms Bullet’s native implementations and objects behave realistically. Categories and Subject Descriptors (according to ACM CCS): Computing Methodologies [I.3.5]: Computational Geometry and Object Modeling—Geometric algorithms, Object hierarchies; Computing Methodologies [I.3.7]: Three-Dimensional Graphics and Realism—Animation, Virtual reality. 1. Introduction The physics library Bullet [Cou14] provides with several collision detection implementations able to handle simple Methods that perform collision detection and force compu- geometries and a powerful rigid body dynamics framework.
    [Show full text]
  • Continuous Collision Principle Software Engineer, Blizzard
    Erin Catto, @erin_catto Continuous Collision Principle Software Engineer, Blizzard Expert Lego Set Number 952, 315 pieces, 1978 Games are fancy flipbooks Games are just fancy flip books. We draw discrete frames that are snapshots of a moving world. Of course the difference is that in a game, the player can influence what is drawn in each frame. Physics engines usually operate in the same way. The engine executes discrete time steps, usually of a fixed size, that march the simulation forward in time. When we do this, the physics engine can miss events that happen in between frames. Discrete steps lead to missed events Consider a bouncing ball. Discrete time steps are good enough for most of the simulation. However, suppose the discrete time steps skip over the time where the ball hits the floor. How can the ball bounce if it never touches the floor? Well it won't and this is a big problem for physics engines. Solution #1: Ignore the bug Bye! If you ignore the missed collision you can get tunneling. In this case the ball falls out of the world. Many physics engines don’t address this problem and leave it up to the game to fix (or ignore the problem). In some cases this is a reasonable choice. For example, if two pieces of debris pass through each other quickly in a game, you may never notice and it doesn’t effect the outcome of the game. Solution #2: Make the floor thicker You can prevent missed collisions by using more forgiving geometry. In this case I made the floor thicker to catch the ball.
    [Show full text]
  • Collision Detection for Deformable Objects
    Collision Detection for Deformable Objects Matthias Teschner, Stefan Kimmerle, Bruno Heidelberger, Gabriel Zachmann, Laks Raghupathi, Arnulph Fuhrmann, Marie-Paule Cani, François Faure, Nadia Magnenat-Thalmann, Wolfgang Strasser, et al. To cite this version: Matthias Teschner, Stefan Kimmerle, Bruno Heidelberger, Gabriel Zachmann, Laks Raghupathi, et al.. Collision Detection for Deformable Objects. Eurographics State-of-the-Art Report (EG-STAR), Aug 2004, Grenoble, France. inria-00539916 HAL Id: inria-00539916 https://hal.inria.fr/inria-00539916 Submitted on 25 Nov 2010 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Volume xx , Number x Collision Detection for Deformable Objects M. Teschner1, S. Kimmerle3, B. Heidelberger2, G. Zachmann6, L. Raghupathi5, A. Fuhrmann7, M.-P. Cani5, F. Faure5, N. Magnenat-Thalmann4, W. Strasser3, P. Volino4 1 Computer Graphics Laboratory, University of Freiburg, Germany 2 Computer Graphics Laboratory, ETH Zurich, Switzerland 3 WSI/GRIS, Tübingen University, Germany 4 Miralab, University of Geneva, Switzerland 5 GRAVIR/IMAG, INRIA Grenoble, France 6 Bonn University, Germany 7 Fraunhofer Institute for Computer Graphics, Darmstadt, Germany Abstract Interactive environments for dynamically deforming objects play an important role in surgery simulation and entertainment technology. These environments require fast deformable models and very efficient collision han- dling techniques.
    [Show full text]
  • Systematic Literature Review of Realistic Simulators Applied in Educational Robotics Context
    sensors Systematic Review Systematic Literature Review of Realistic Simulators Applied in Educational Robotics Context Caio Camargo 1, José Gonçalves 1,2,3 , Miguel Á. Conde 4,* , Francisco J. Rodríguez-Sedano 4, Paulo Costa 3,5 and Francisco J. García-Peñalvo 6 1 Instituto Politécnico de Bragança, 5300-253 Bragança, Portugal; [email protected] (C.C.); [email protected] (J.G.) 2 CeDRI—Research Centre in Digitalization and Intelligent Robotics, 5300-253 Bragança, Portugal 3 INESC TEC—Institute for Systems and Computer Engineering, 4200-465 Porto, Portugal; [email protected] 4 Robotics Group, Engineering School, University of León, Campus de Vegazana s/n, 24071 León, Spain; [email protected] 5 Universidade do Porto, 4200-465 Porto, Portugal 6 GRIAL Research Group, Computer Science Department, University of Salamanca, 37008 Salamanca, Spain; [email protected] * Correspondence: [email protected] Abstract: This paper presents a systematic literature review (SLR) about realistic simulators that can be applied in an educational robotics context. These simulators must include the simulation of actuators and sensors, the ability to simulate robots and their environment. During this systematic review of the literature, 559 articles were extracted from six different databases using the Population, Intervention, Comparison, Outcomes, Context (PICOC) method. After the selection process, 50 selected articles were included in this review. Several simulators were found and their features were also Citation: Camargo, C.; Gonçalves, J.; analyzed. As a result of this process, four realistic simulators were applied in the review’s referred Conde, M.Á.; Rodríguez-Sedano, F.J.; context for two main reasons. The first reason is that these simulators have high fidelity in the robots’ Costa, P.; García-Peñalvo, F.J.
    [Show full text]
  • Initial Steps for the Coupling of Javascript Physics Engines with X3DOM
    Workshop on Virtual Reality Interaction and Physical Simulation VRIPHYS (2013) J. Bender, J. Dequidt, C. Duriez, and G. Zachmann (Editors) Initial Steps for the Coupling of JavaScript Physics Engines with X3DOM L. Huber1 1Fraunhofer IGD, Germany Abstract During the past years, first physics engines based on JavaScript have been developed for web applications. These are capable of displaying virtual scenes much more realistically. Thus, new application areas can be opened up, particularly with regard to the coupling of X3DOM-based 3D models. The advantage is that web-based applica- tions are easily accessible to all users. Furthermore, such engines allow popularizing and presenting simulation results without having to compile large simulation software. This paper provides an overview and a comparison of existing JavaScript physics engines. It also introduces a guideline for the derivation of a physical model based on a 3D model in X3DOM. The aim of using JavaScript physics engines is not only to virtually visualize designed products but to simulate them as well. The user is able to check and test an individual product virtually and interactively in a browser according to physically correct behavior regarding gravity, friction or collision. It can be used for verification in the design phase or web-based training purposes. Categories and Subject Descriptors (according to ACM CCS): I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling—Physically based modeling I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism—Virtual reality I.6.4 [Computer Graphics]: Model Validation and Analysis— 1. Introduction of water or particle systems, e.g. the visualization of gas dis- persion, are to be described.
    [Show full text]