Pub Date : 1900-01-01DOI: 10.2312/vriphys.20151338
N. Chentanez, Matthias Müller, M. Macklin, Tae-Yong Kim
We present the first mesh-based surface tracker that runs entirely on the GPU. The surface tracker is both completely grid-free and fast which makes it suitable for the use in a large, unbounded domain. The key idea for handling topological changes is to detect and delete overlapping triangles as well as triangles that lie inside the volume. The holes are then joined or closed in a robust and efficient manner. Good mesh quality is maintained by a mesh improvement algorithm. In this paper we describe how all these steps can be parallelized to run efficiently on a GPU. The surface tracker is guaranteed to produce a manifold mesh without boundary. Our results show the quality and efficiency of the method in both Eulerian and Lagrangian liquid simulations. Our parallel implementation runs more than an order of magnitude faster than the CPU version.
{"title":"Grid-Free Surface Tracking on the GPU","authors":"N. Chentanez, Matthias Müller, M. Macklin, Tae-Yong Kim","doi":"10.2312/vriphys.20151338","DOIUrl":"https://doi.org/10.2312/vriphys.20151338","url":null,"abstract":"We present the first mesh-based surface tracker that runs entirely on the GPU. The surface tracker is both completely grid-free and fast which makes it suitable for the use in a large, unbounded domain. The key idea for handling topological changes is to detect and delete overlapping triangles as well as triangles that lie inside the volume. The holes are then joined or closed in a robust and efficient manner. Good mesh quality is maintained by a mesh improvement algorithm. In this paper we describe how all these steps can be parallelized to run efficiently on a GPU. The surface tracker is guaranteed to produce a manifold mesh without boundary. Our results show the quality and efficiency of the method in both Eulerian and Lagrangian liquid simulations. Our parallel implementation runs more than an order of magnitude faster than the CPU version.","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"352 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131562663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/vriphys.20151336
T. Knott, T. Kuhlen
Common approaches for the haptic rendering of complex scenarios employ multi-rate simulation schemes. Here, the collision queries or the simulation of a complex deformable object are often performed asynchronously on a lower frequency, while some kind of intermediate contact representation is used to simulate interactions on the haptic rate. However, this can produce artifacts in the haptic rendering when the contact situation quickly changes and the intermediate representation is not able to reflect the changes due to the lower update rate. We address this problem utilizing a novel contact model. It facilitates the creation of contact representations that are accurate for a large range of motions and multiple simulation time-steps. We handle problematic convex contact regions using a local convex decomposition and special constraints for convex areas. We combine our accurate contact model with an implicit temporal integration scheme to create an intermediate mechanical contact representation, which reflects the dynamic behavior of the simulated objects. Moreover, we propose a new iterative solving scheme for the involved constrained dynamics problems. We increase the robustness of our method using techniques from trust region-based optimization. Our approach can be combined with standard methods for the modeling of deformable objects or constraint-based approaches for the modeling of, for instance, friction or joints. We demonstrate its benefits with respect to the simulation accuracy and the quality of the rendered haptic forces in multiple scenarios.
{"title":"Accurate Contact Modeling for Multi-rate Single-point Haptic Rendering of Static and Deformable Environments","authors":"T. Knott, T. Kuhlen","doi":"10.2312/vriphys.20151336","DOIUrl":"https://doi.org/10.2312/vriphys.20151336","url":null,"abstract":"Common approaches for the haptic rendering of complex scenarios employ multi-rate simulation schemes. Here, the collision queries or the simulation of a complex deformable object are often performed asynchronously on a lower frequency, while some kind of intermediate contact representation is used to simulate interactions on the haptic rate. However, this can produce artifacts in the haptic rendering when the contact situation quickly changes and the intermediate representation is not able to reflect the changes due to the lower update rate. We address this problem utilizing a novel contact model. It facilitates the creation of contact representations that are accurate for a large range of motions and multiple simulation time-steps. We handle problematic convex contact regions using a local convex decomposition and special constraints for convex areas. We combine our accurate contact model with an implicit temporal integration scheme to create an intermediate mechanical contact representation, which reflects the dynamic behavior of the simulated objects. Moreover, we propose a new iterative solving scheme for the involved constrained dynamics problems. We increase the robustness of our method using techniques from trust region-based optimization. Our approach can be combined with standard methods for the modeling of deformable objects or constraint-based approaches for the modeling of, for instance, friction or joints. We demonstrate its benefits with respect to the simulation accuracy and the quality of the rendered haptic forces in multiple scenarios.","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132779701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/PE/vriphys/vriphys10/049-058
K. Larsson, G. Wallgren, M. Larson
This paper introduces a continuum mechanics based thread model for use in real-time simulation. The model includes both rotary inertia, shear deformation and torsion. It is based on a three-dimensi ...
{"title":"Interactive Simulation of a Continuum Mechanics based Torsional Thread","authors":"K. Larsson, G. Wallgren, M. Larson","doi":"10.2312/PE/vriphys/vriphys10/049-058","DOIUrl":"https://doi.org/10.2312/PE/vriphys/vriphys10/049-058","url":null,"abstract":"This paper introduces a continuum mechanics based thread model for use in real-time simulation. The model includes both rotary inertia, shear deformation and torsion. It is based on a three-dimensi ...","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129621087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/PE/vriphys/vriphys12/127-136
J. Bender, Arjan Kuijper, D. W. Fellner, É. Guérin, Eugen Dyck, E. Zell, Agnes Kohsik, P. Grewe, York Winter, M. Piefke, Mario Botsch
We present the OCTAVIS system, a novel virtual reality platform developed for rehabilitation and training of patients with brain function disorders. To meet the special requirements of clinical studies, our system has been designed with ease of use, patient safety, ease of maintenance, space and cost efficiency in mind. Patients are sitting on a rotating office chair in the center of eight touch screen displays arranged in octagon around them, thereby providing a 360◦ horizontal panorama view. Navigation is intuitively controlled through chair rotation and a joystick in the armrest. A touch interface enables easy object selection. The OCTAVIS system has been successfully deployed to four hospitals. We report first results of clinical studies conducted with patients and control groups, demonstrating that our system is immersive, easy to use, and supportive for rehabilitation purposes.
{"title":"OCTAVIS: An Easy-to-Use VR-System for Clinical Studies","authors":"J. Bender, Arjan Kuijper, D. W. Fellner, É. Guérin, Eugen Dyck, E. Zell, Agnes Kohsik, P. Grewe, York Winter, M. Piefke, Mario Botsch","doi":"10.2312/PE/vriphys/vriphys12/127-136","DOIUrl":"https://doi.org/10.2312/PE/vriphys/vriphys12/127-136","url":null,"abstract":"We present the OCTAVIS system, a novel virtual reality platform developed for rehabilitation and training of patients with brain function disorders. To meet the special requirements of clinical studies, our system has been designed with ease of use, patient safety, ease of maintenance, space and cost efficiency in mind. Patients are sitting on a rotating office chair in the center of eight touch screen displays arranged in octagon around them, thereby providing a 360◦ horizontal panorama view. Navigation is intuitively controlled through chair rotation and a joystick in the armrest. A touch interface enables easy object selection. The OCTAVIS system has been successfully deployed to four hospitals. We report first results of clinical studies conducted with patients and control groups, demonstrating that our system is immersive, easy to use, and supportive for rehabilitation purposes.","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124899146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/vriphys.20181067
F. Dagenais, Julián Guzman, Valentin Vervondel, A. Hay, S. Delorme, D. Mould, Eric Paquette
We propose an approach for real-time shallow water simulation, building upon the virtual pipes model with multi-layered heightmaps. Our approach introduces the use of extended pipes which resolve flow through fully-flooded passages, which is not possible using current multi-layered techniques. We extend the virtual pipe method with a physically-based viscosity model that is both fast and stable. Our viscosity model is integrated implicitly without the expense of solving a large linear system. The liquid is rendered as a triangular mesh surface built from a heightmap. We propose a novel surface optimization approach that prevents interpenetrations of the liquid surface with the underlying terrain geometry. To improve the realism of small-scale scenarios, we present a meniscus shading approach that adjusts the liquid surface normals based on a distance field. Our approach runs in real time on various scenarios of roughly 10 x 10 cm at a resolution of 0.5 mm, with up to five layers. CCS Concepts •Computing methodologies → Physical simulation;
我们提出了一种基于多层高度图的虚拟管道模型的实时浅水模拟方法。我们的方法引入了扩展管道的使用，通过完全淹没的通道解决流动，这是不可能使用当前的多层技术。我们将虚拟管道方法扩展为基于物理的粘度模型，该模型既快速又稳定。我们的黏度模型是隐式集成的，无需求解大型线性系统。液体被渲染成一个由高度图构建的三角形网格表面。我们提出了一种新的表面优化方法，可以防止液体表面与下垫地形几何形状的相互渗透。为了提高小尺度场景的真实感，我们提出了一种基于距离场调整液体表面法线的半月板遮阳方法。我们的方法可以实时运行在大约10 x 10厘米的各种场景中，分辨率为0.5毫米，最多有五层。•计算方法→物理模拟;
{"title":"Real-Time Virtual Pipes Simulation and Modeling for Small-Scale Shallow Water","authors":"F. Dagenais, Julián Guzman, Valentin Vervondel, A. Hay, S. Delorme, D. Mould, Eric Paquette","doi":"10.2312/vriphys.20181067","DOIUrl":"https://doi.org/10.2312/vriphys.20181067","url":null,"abstract":"We propose an approach for real-time shallow water simulation, building upon the virtual pipes model with multi-layered heightmaps. Our approach introduces the use of extended pipes which resolve flow through fully-flooded passages, which is not possible using current multi-layered techniques. We extend the virtual pipe method with a physically-based viscosity model that is both fast and stable. Our viscosity model is integrated implicitly without the expense of solving a large linear system. The liquid is rendered as a triangular mesh surface built from a heightmap. We propose a novel surface optimization approach that prevents interpenetrations of the liquid surface with the underlying terrain geometry. To improve the realism of small-scale scenarios, we present a meniscus shading approach that adjusts the liquid surface normals based on a distance field. Our approach runs in real time on various scenarios of roughly 10 x 10 cm at a resolution of 0.5 mm, with up to five layers. CCS Concepts •Computing methodologies → Physical simulation;","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"2018 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129240942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/vriphys.20181068
Stefan Band, Christoph Gissler, A. Peer, M. Teschner
We propose a novel method to predict pressure values at boundary particles in incompressible divergence-free SPH simulations (DFSPH). Our approach employs Moving Least Squares (MLS) to predict the pressure at boundary particles. Therefore, MLS computes hyperplanes that approximate the pressure field at the interface between fluid and boundary particles. We compare this approach with two previous techniques. One previous technique mirrors the pressure from fluid to boundary particles. The other one extrapolates the pressure from fluid to boundary particles, but uses a gradient that is computed with Smoothed Particle Hydrodynamics (SPH). We motivate that gradient-based extrapolation is more accurate than mirroring. We further motivate that our proposed MLS gradient is less error prone than the SPH gradient at the boundary. In our experiments, we indicate artifacts in previous approaches. We show that these artifacts are significantly reduced with our approach resulting in simulation steps that can be twice as large compared to previous methods. We further present challenging and complex scenarios to illustrate the capabilities of the proposed boundary handling. CCS Concepts •Computing methodologies → Physical simulation; Massively parallel and high-performance simulations;
{"title":"MLS Pressure Extrapolation for the Boundary Handling in Divergence-Free SPH","authors":"Stefan Band, Christoph Gissler, A. Peer, M. Teschner","doi":"10.2312/vriphys.20181068","DOIUrl":"https://doi.org/10.2312/vriphys.20181068","url":null,"abstract":"We propose a novel method to predict pressure values at boundary particles in incompressible divergence-free SPH simulations (DFSPH). Our approach employs Moving Least Squares (MLS) to predict the pressure at boundary particles. Therefore, MLS computes hyperplanes that approximate the pressure field at the interface between fluid and boundary particles. We compare this approach with two previous techniques. One previous technique mirrors the pressure from fluid to boundary particles. The other one extrapolates the pressure from fluid to boundary particles, but uses a gradient that is computed with Smoothed Particle Hydrodynamics (SPH). We motivate that gradient-based extrapolation is more accurate than mirroring. We further motivate that our proposed MLS gradient is less error prone than the SPH gradient at the boundary. In our experiments, we indicate artifacts in previous approaches. We show that these artifacts are significantly reduced with our approach resulting in simulation steps that can be twice as large compared to previous methods. We further present challenging and complex scenarios to illustrate the capabilities of the proposed boundary handling. CCS Concepts •Computing methodologies → Physical simulation; Massively parallel and high-performance simulations;","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129443705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/vriphys.20171087
Alejandro Granados, J. Perháč, L. Rosby, Yee Mun Lee, G. Tan, T. C. Tan, J. Higham, N. Magnenat-Thalmann, N. Low-Beer, F. Bello
Objective: Motivated by the limitations of being unable to provide feedback and adequately assess technical skills whilst training unsighted physical examinations, such as Digital Rectal Examinations (DRE), we present a see-through visualisation system that can be used with benchtop models widely available in medical schools. Methods: We use position and pressure sensors located on the examining finger and have implemented a Virtual Reality (VR) simulation learning tool consisting of registered 3D models of the benchtop, augmented with relevant surrounding pelvic anatomy. The proposed system was evaluated with six medical students and eleven consultants. Results: The system is stable, runs in real time, uses unobtrusive sensor coils and pads, is able to capture data from sensors at 40Hz and adequately translates and rotates the position of the examining finger aligned to the 3D models of the benchtop and surrounding anatomy. Both medical students and consultants recognised the educational value of being able to see-through and visualise surrounding relevant anatomy. Although novices are reported to be the group that could benefit the most from our system, it is crucial not to be over reliant on visual cues for too long and to develop a strategy for the adequate use of the see-through system. Conclusions: The proposed VR simulation system is intended to improve the experience of novices learning unsighted examinations by providing real-time feedback and visualisation, allowing trainees to reflect on their performance and permitting more adequate assessment of technical skills.
{"title":"See-through Visualisation for Training and Assessing Unsighted Physical Examinations","authors":"Alejandro Granados, J. Perháč, L. Rosby, Yee Mun Lee, G. Tan, T. C. Tan, J. Higham, N. Magnenat-Thalmann, N. Low-Beer, F. Bello","doi":"10.2312/vriphys.20171087","DOIUrl":"https://doi.org/10.2312/vriphys.20171087","url":null,"abstract":"Objective: Motivated by the limitations of being unable to provide feedback and adequately assess technical skills whilst training unsighted physical examinations, such as Digital Rectal Examinations (DRE), we present a see-through visualisation system that can be used with benchtop models widely available in medical schools. Methods: We use position and pressure sensors located on the examining finger and have implemented a Virtual Reality (VR) simulation learning tool consisting of registered 3D models of the benchtop, augmented with relevant surrounding pelvic anatomy. The proposed system was evaluated with six medical students and eleven consultants. Results: The system is stable, runs in real time, uses unobtrusive sensor coils and pads, is able to capture data from sensors at 40Hz and adequately translates and rotates the position of the examining finger aligned to the 3D models of the benchtop and surrounding anatomy. Both medical students and consultants recognised the educational value of being able to see-through and visualise surrounding relevant anatomy. Although novices are reported to be the group that could benefit the most from our system, it is crucial not to be over reliant on visual cues for too long and to develop a strategy for the adequate use of the see-through system. Conclusions: The proposed VR simulation system is intended to improve the experience of novices learning unsighted examinations by providing real-time feedback and visualisation, allowing trainees to reflect on their performance and permitting more adequate assessment of technical skills.","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124297874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/vriphys.20141226
Eusebio Ricardez, J. Noguez, L. Neri, Lourdes Muñoz-Gómez, David Escobar-Castillejos
Surgical procedures require a high degree of complexity and difficulty. Consequently, extensive preparation in the learning process of medical students is necessary in order to perform suturing tasks successfully. Some authors suggest that a minimum of 750 operations are needed to acquire the experience to perform correctly surgical procedures. Moreover, current laws establish standards if corpses and animals are used as medical learning environments; as a result, the development of skills and processes is hindered. This paper introduces the development of a virtual environment for training suture skills: SutureHap, which uses two Sensable Phantom Omni haptic devices. To create a proper simulation of the human skin which must fulfill graphic and physical characteristics, NVIDIA PhysX libraries were usea. Some of these libraries were originally defined to represent cloths; however, in this work some parameters were adjusted to obtain the desired simulation. An architecture that facilitates the integration of haptic devices was designed. A simplified method of collision detection and haptic feedback generation was created. This enabled the reduction of complexity generated during collision detection, and it diminished the time to develop the virtual environment. Tweezers, thread and needle models were added in the virtual environment. Due to fact that PhysX exploits GPU processing, response time was improved during modeling of the skin. Additionally, suturing tasks were designed by taking into consideration real procedures made by medical experts. The acquisition of skills and competencies in suture process are increased through haptic devices due to the fact that they can send tactile sensations. These environments decrease costs and risks, and provide real sensations as the ones that can be perceived in current learning environments. Finally, an evaluation focused on the perception of this environment was made by students. Preliminary results are promising, and it is expected that this environment facilitates the acquisition of suture skills.
{"title":"SutureHap: A Suture Simulator with Haptic Feedback","authors":"Eusebio Ricardez, J. Noguez, L. Neri, Lourdes Muñoz-Gómez, David Escobar-Castillejos","doi":"10.2312/vriphys.20141226","DOIUrl":"https://doi.org/10.2312/vriphys.20141226","url":null,"abstract":"Surgical procedures require a high degree of complexity and difficulty. Consequently, extensive preparation in the learning process of medical students is necessary in order to perform suturing tasks successfully. Some authors suggest that a minimum of 750 operations are needed to acquire the experience to perform correctly surgical procedures. Moreover, current laws establish standards if corpses and animals are used as medical learning environments; as a result, the development of skills and processes is hindered. This paper introduces the development of a virtual environment for training suture skills: SutureHap, which uses two Sensable Phantom Omni haptic devices. To create a proper simulation of the human skin which must fulfill graphic and physical characteristics, NVIDIA PhysX libraries were usea. Some of these libraries were originally defined to represent cloths; however, in this work some parameters were adjusted to obtain the desired simulation. An architecture that facilitates the integration of haptic devices was designed. A simplified method of collision detection and haptic feedback generation was created. This enabled the reduction of complexity generated during collision detection, and it diminished the time to develop the virtual environment. Tweezers, thread and needle models were added in the virtual environment. Due to fact that PhysX exploits GPU processing, response time was improved during modeling of the skin. Additionally, suturing tasks were designed by taking into consideration real procedures made by medical experts. The acquisition of skills and competencies in suture process are increased through haptic devices due to the fact that they can send tactile sensations. These environments decrease costs and risks, and provide real sensations as the ones that can be perceived in current learning environments. Finally, an evaluation focused on the perception of this environment was made by students. Preliminary results are promising, and it is expected that this environment facilitates the acquisition of suture skills.","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"139 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124374665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/PE/vriphys/vriphys11/093-100
Gabriel Notman, P. Carlisle, S. Manning
Proportional plus Derivative (PD) control has been used widely to calculate the required forces to drive physically-based character animation. This approach requires the measurement of the state error or the difference between the measured and desired motion of the animated model. In this paper, three methods for measuring this state error are presented and compared. This includes a new method which focuses on minimising any accumulated linear transform error from rotational joints. All three methods were compared by measuring how precisely they were able to track a series of animation trajectories using a common setup. The new method presented here demonstrates improved tracking precision, particularly in cases where the kinematic dimensions of the animated model vary from those specified in the source animation.
{"title":"Methods for Measuring State Error for Control of Animated Human Figures","authors":"Gabriel Notman, P. Carlisle, S. Manning","doi":"10.2312/PE/vriphys/vriphys11/093-100","DOIUrl":"https://doi.org/10.2312/PE/vriphys/vriphys11/093-100","url":null,"abstract":"Proportional plus Derivative (PD) control has been used widely to calculate the required forces to drive physically-based character animation. This approach requires the measurement of the state error or the difference between the measured and desired motion of the animated model. In this paper, three methods for measuring this state error are presented and compared. This includes a new method which focuses on minimising any accumulated linear transform error from rotational joints. All three methods were compared by measuring how precisely they were able to track a series of animation trajectories using a common setup. The new method presented here demonstrates improved tracking precision, particularly in cases where the kinematic dimensions of the animated model vary from those specified in the source animation.","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"272 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122770372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.2312/PE/vriphys/vriphys10/115-124
Dominik Rausch, I. Assenmacher, T. Kuhlen
We present a comprehensive 3D sketch recognition framework for interaction within Virtual Environments that allows to trigger commands by drawing symbols, which are recognized by a multi-level analysis. It proceeds in three steps: The segmentation partitions each input line into meaningful segments, which are then recognized as a primitive shape, and finally analyzed as a whole sketch by a symbol matching step. The whole framework is configurable over well-defined interfaces, utilizing a fuzzy logic algorithm for primitive shape learning and a textual description language to define compound symbols. It allows an individualized interaction approach that can be used without much training and provides a good balance between abstraction and intuition. We show the real-time applicability of our approach by performance measurements.
{"title":"3D Sketch Recognition for Interaction in Virtual Environments","authors":"Dominik Rausch, I. Assenmacher, T. Kuhlen","doi":"10.2312/PE/vriphys/vriphys10/115-124","DOIUrl":"https://doi.org/10.2312/PE/vriphys/vriphys10/115-124","url":null,"abstract":"We present a comprehensive 3D sketch recognition framework for interaction within Virtual Environments that allows to trigger commands by drawing symbols, which are recognized by a multi-level analysis. It proceeds in three steps: The segmentation partitions each input line into meaningful segments, which are then recognized as a primitive shape, and finally analyzed as a whole sketch by a symbol matching step. The whole framework is configurable over well-defined interfaces, utilizing a fuzzy logic algorithm for primitive shape learning and a textual description language to define compound symbols. It allows an individualized interaction approach that can be used without much training and provides a good balance between abstraction and intuition. We show the real-time applicability of our approach by performance measurements.","PeriodicalId":446363,"journal":{"name":"Workshop on Virtual Reality Interactions and Physical Simulations","volume":"238 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123038884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：