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1 – 10 of 179Hanxiang Xu, Shihui Guo, Junfeng Yao and Nadia Magnenat Thalmann
In the process of robot shell design, it is necessary to match the shape of the input 3D original character mesh model and robot endoskeleton, in order to make the input model fit…
Abstract
Purpose
In the process of robot shell design, it is necessary to match the shape of the input 3D original character mesh model and robot endoskeleton, in order to make the input model fit for robot and avoid collision. So, the purpose of this paper is to find an object of reference, which can be used for the process of shape matching.
Design/methodology/approach
In this work, the authors propose an interior bounded box (IBB) approach that derives from oriented bounding box (OBB). This kind of box is inside the closed mesh model. At the same time, it has maximum volume which is aligned with the object axis but is enclosed by all the mesh vertices. Based on the IBB of input mesh model and the OBB of robot endoskeleton, the authors can complete the process of shape matching. In this paper, the authors use an evolutionary algorithm, covariance matrix adaptation evolution strategy (CMA-ES), to approximate the IBB based on skeleton and symmetry of input character mesh model.
Findings
Based on the evolutionary algorithm CMA-ES, the optimal position and scale information of IBB can be found. The authors can obtain satisfactory IBB result after this optimization process. The output IBB has maximum volume and is enveloped by the input character mesh model as well.
Originality/value
To the best knowledge of the authors, the IBB is first proposed and used in the field of robot shell design. Taking advantage of the IBB, people can quickly obtain a shell model that fit for robot. At the same time, it can avoid collision between shell model and the robot endoskeleton.
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Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community…
Abstract
Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.
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Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines;…
Abstract
Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.
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David G. Alciatore and Terry T. Wohlers
Focuses on the development and testing of software for reading and formatting digitized data and exporting it to rapid prototyping (RP). Research and development over two years…
Abstract
Focuses on the development and testing of software for reading and formatting digitized data and exporting it to rapid prototyping (RP). Research and development over two years has involved the implementation of special computer‐aided sculpting software that runs on UNIX workstations and which imports 3D polygonal mesh data in STL, OBJ and DXF formats, then re‐shapes it, much like the pushing and pulling on the surface of a rubber membrane. Specifying a wall thickness gives the model volume, prior to exporting an STL file. Describes how data has been imported form laser digitizing systems, had its shape changed and then how RP parts have been created from the model data.
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Zhijia Dong, Gaoming Jiang, Guoming Huang and Honglian Cong
The virtual display of 3D garment is one of the most important features in a computer-aided garment design system. The purpose of this paper is to present a novel web-based 3D…
Abstract
Purpose
The virtual display of 3D garment is one of the most important features in a computer-aided garment design system. The purpose of this paper is to present a novel web-based 3D virtual display framework for the online design of warp-knitted seamless garment using the latest WebGL and HTML5 technologies.
Design/methodology/approach
Based on the feature-based parametric 3D human body model, the 3D model of skin-tight warp-knitted seamless garment is established using the geometric modeling method. By applying plane parameterization technology, the 3D garment model is then projected into corresponding 2D prototype pattern and a texture-mapping relationship is obtained. Finally, an online 3D virtual display application framework for warp-knitted seamless garment is implemented on modern WebGL-enabled web browsers using the latest WebGL and HTML5 technologies, which allow garment designers to globally access without installing any additional software or plugin.
Findings
Based on the 2D/3D model of warp-knitted seamless garment, an online 3D virtual display application running on modern WebGL-enabled web browser is implemented using the latest Javascript, WebGL and HTML5 technologies, which is proven to be an effective way for building the web-based 3D garment CAD systems.
Originality/value
This paper provides a parametric design method for warp-knitted seamless garment 2D/3D model, and web-based online virtual display of 3D warp-knitted seamless garment is implemented for the first time, which establishes the foundation for the web-based online computer-aided warp-knitted seamless garment design system.
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Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…
Abstract
Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.
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Jun‐Bao Li, Meng Li and Huijun Gao
Computer‐aided fragmented cultural relics repair is an effective method instead of manual repair. The purpose of this paper is to provide a 3D digital patching system for…
Abstract
Purpose
Computer‐aided fragmented cultural relics repair is an effective method instead of manual repair. The purpose of this paper is to provide a 3D digital patching system for computer‐aided cultural relics repair through using the scanned 3D data of fragmented cultural relics. It includes processes and tools that can be effectively used for fragmented cultural relics repair.
Design/methodology/approach
An automatic 3D digital patching for fragmented culture relics repair is designed. The framework includes a surface segmentation based on region dilation, feature extraction based on height‐map, pair matching and multi‐block matching.
Findings
The paper finds that the proposed 3D data patching is an efficient method for fragmented cultural relics repair.
Practical implications
Early and effective planning and implementation of computer‐aided fragmented cultural relics repair can significantly improve the reliability and availability of fragmented cultural relics repair.
Originality/value
The paper presents a uniform framework of 3D digital patching for fragmented cultural relics repair.
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Boxiang Xiao, Zhengdong Liu, Jia Shi and Yuanxia Wang
Accurate and automatic clothing pattern making is very important in personalized clothing customization and virtual fitting room applications. Clothing pattern generating as well…
Abstract
Purpose
Accurate and automatic clothing pattern making is very important in personalized clothing customization and virtual fitting room applications. Clothing pattern generating as well as virtual clothing simulation is an attractive research issue both in clothing industry and computer graphics.
Design/methodology/approach
Physics-based method is an effective way to model dynamic process and generate realistic clothing animation. Due to conceptual simplicity and computational speed, mass-spring model is frequently used to simulate deformable and soft objects follow the natural physical rules. We present a physics-based clothing pattern generating framework by using scanned human body model. After giving a scanned human body model, first, we extract feature points, planes and curves on the 3D model by geometric analysis, and then, we construct a remeshed surface which has been formatted to connected quad meshes. Second, for each clothing piece in 3D, we construct a mass-spring model with same topological structures, and conduct a typical time integration algorithm to the mass-spring model. Finally, we get the convergent clothing pieces in 2D of all clothing parts, and we reconnected parts which are adjacent on 3D model to generate the basic clothing pattern.
Findings
The results show that the presented method is a feasible way for clothing pattern generating by use of scanned human body model.
Originality/value
The main contribution of this work is twofold: one is the geometric algorithm to scanned human body model, which is specially conducted for clothing pattern design to extract feature points, planes and curves. This is the crucial base for suit clothing pattern generating. Another is the physics-based pattern generating algorithm which flattens the 3D shape to 2D shape of cloth pattern pieces.
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Xiaotong Jiang, Xiaosheng Cheng, Qingjin Peng, Luming Liang, Ning Dai, Mingqiang Wei and Cheng Cheng
It is a challenge to print a model with the size that is larger than the working volume of a three-dimensional (3D) printer. The purpose of this paper is to present a feasible…
Abstract
Purpose
It is a challenge to print a model with the size that is larger than the working volume of a three-dimensional (3D) printer. The purpose of this paper is to present a feasible approach to divide a large model into small printing parts to fit the volume of a printer and then assemble these parts into the final model.
Design/methodology/approach
The proposed approach is based on the skeletonization and the minima rule. The skeleton of a printing model is first extracted using the mesh contraction and the principal component analysis. The 3D model is then partitioned preliminarily into many smaller parts using the space sweep method and the minima rule. The preliminary partition is finally optimized using the greedy algorithm.
Findings
The skeleton of a 3D model can effectively represent a simplified version of the geometry of the 3D model. Using a model’s skeleton to partition the model is an efficient way. As it is generally desirable to have segmentations at concave creases and seams, the cutting position should be located in the concave region. The proposed approach can partition large models effectively to well retain the integrity of meaningful parts.
Originality/value
The proposed approach is new in the rapid prototyping field using the model skeletonization and the minima rule. Based on the authors’ knowledge, there is no method that concerns the integrity of meaningful parts for partitioning. The proposed method can achieve satisfactory results by the integrity of meaningful parts and assemblability for most 3D models.
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Ruding Lou, Jean-Philippe Pernot, Franca Giannini, Philippe Veron and Bianca Falcidieno
The purpose of this paper is to set up a new framework to enable direct modifications of volume meshes enriched with semantic information associated to multiple partitions. An…
Abstract
Purpose
The purpose of this paper is to set up a new framework to enable direct modifications of volume meshes enriched with semantic information associated to multiple partitions. An instance of filleting operator is prototyped under this framework and presented in the paper.
Design/methodology/approach
In this paper, a generic mesh modification operator has been designed and a new instance of this operator for filleting finite element (FE) sharp edges of tetrahedral multi-partitioned meshes is also pro-posed. The filleting operator works in two main steps. The outer skin of the tetrahedral mesh is first deformed to round user-specified sharp edges while satisfying constraints relative to the shape of the so-called Virtual Group Boundaries. Then, in the filleting area, the positions of the inner nodes are relaxed to improve the aspect ratio of the mesh elements.
Findings
The classical mainstream methodology for product behaviour optimization involves the repetition of four steps: CAD modelling, meshing of CAD models, enrichment of models with FE simulation semantics and FEA. This paper highlights how this methodology could be simplified by two steps: simulation model modification and FEA. The authors set up a new framework to enable direct modifications of volume meshes enriched with semantic information associated to multiple partitions and the corresponding fillet operator is devised.
Research limitations/implications
The proposed framework shows only a paradigm of direct modifications of semantic enriched meshes. It could be further more improved by adding or changing the modules inside. The fillet operator does not take into account the exact radius imposed by user. With this proposed fillet operator the mesh element density may not be enough high to obtain wished smoothness.
Originality/value
This paper fulfils an identified industry need to speed up the product behaviour analysis process by directly modifying the simulation semantic enriched meshes.
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