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A Three-Grid High-Order Immersed Finite Element Method for the Analysis of CAD Models 用于分析 CAD 模型的三网格高阶沉浸式有限元方法
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-05-23 DOI: 10.1016/j.cad.2024.103730
Eky Febrianto , Jakub Šístek , Pavel Kůs , Matija Kecman , Fehmi Cirak
{"title":"A Three-Grid High-Order Immersed Finite Element Method for the Analysis of CAD Models","authors":"Eky Febrianto ,&nbsp;Jakub Šístek ,&nbsp;Pavel Kůs ,&nbsp;Matija Kecman ,&nbsp;Fehmi Cirak","doi":"10.1016/j.cad.2024.103730","DOIUrl":"10.1016/j.cad.2024.103730","url":null,"abstract":"<div><p>The automated finite element analysis of complex CAD models using boundary-fitted meshes is rife with difficulties. Immersed finite element methods are intrinsically more robust but usually less accurate. In this work, we introduce an efficient, robust, high-order immersed finite element method for complex CAD models. Our approach relies on three adaptive structured grids: a geometry grid for representing the implicit geometry, a finite element grid for discretising physical fields and a quadrature grid for evaluating the finite element integrals. The geometry grid is a sparse VDB (Volumetric Dynamic B+ tree) grid that is highly refined close to physical domain boundaries. The finite element grid consists of a forest of octree grids distributed over several processors, and the quadrature grid in each finite element cell is an octree grid constructed in a bottom-up fashion. The resolution of the quadrature grid ensures that finite element integrals are evaluated with sufficient accuracy and that any sub-grid geometric features, like small holes or corners, are resolved up to a desired resolution. The conceptual simplicity and modularity of our approach make it possible to reuse open-source libraries, i.e. openVDB and p4est for implementing the geometry and finite element grids, respectively, and BDDCML for iteratively solving the discrete systems of equations in parallel using domain decomposition. We demonstrate the efficiency and robustness of the proposed approach by solving the Poisson equation on domains described by complex CAD models and discretised with tens of millions of degrees of freedom. The solution field is discretised using linear and quadratic Lagrange basis functions.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0010448524000575/pdfft?md5=4a08556c1ca14857794f138fb192f80d&pid=1-s2.0-S0010448524000575-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141191563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
TPMS2STEP: Error-Controlled and C2 Continuity-Preserving Translation of TPMS Models to STEP Files Based on Constrained-PIA TPMS2STEP：将 TPMS 模型翻译为 TPMS2STEP：误差控制和 C2 连续性保护
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-05-22 DOI: 10.1016/j.cad.2024.103726
Yaonaiming Zhao , Qiang Zou , Guoyue Luo , Jiayu Wu , Sifan Chen , Depeng Gao , Minghao Xuan , Fuyu Wang
{"title":"TPMS2STEP: Error-Controlled and C2 Continuity-Preserving Translation of TPMS Models to STEP Files Based on Constrained-PIA","authors":"Yaonaiming Zhao ,&nbsp;Qiang Zou ,&nbsp;Guoyue Luo ,&nbsp;Jiayu Wu ,&nbsp;Sifan Chen ,&nbsp;Depeng Gao ,&nbsp;Minghao Xuan ,&nbsp;Fuyu Wang","doi":"10.1016/j.cad.2024.103726","DOIUrl":"10.1016/j.cad.2024.103726","url":null,"abstract":"<div><p>Triply periodic minimal surface (TPMS) is emerging as an important way of designing microstructures. However, there has been limited use of commercial CAD/CAM/CAE software packages for TPMS design and manufacturing. This is mainly because TPMS is consistently described in the functional representation (F-rep) format, while modern CAD/CAM/CAE tools are built upon the boundary representation (B-rep) format. One possible solution to this gap is translating TPMS to STEP, which is the standard data exchange format of CAD/CAM/CAE. Following this direction, this paper proposes a new translation method with error-controlling and <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> continuity-preserving features. It is based on an approximation error-driven TPMS sampling algorithm and a constrained-PIA algorithm. The sampling algorithm controls the deviation between the original and translated models. With it, an error bound of <span><math><mrow><mn>2</mn><mi>ϵ</mi></mrow></math></span> on the deviation can be ensured if two conditions called <span><math><mi>ϵ</mi></math></span>-density and <span><math><mi>ϵ</mi></math></span>-approximation are satisfied. The constrained-PIA algorithm enforces <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> continuity constraints during TPMS approximation, and meanwhile attaining high efficiency. A theoretical convergence proof of this algorithm is also given. The effectiveness of the translation method has been demonstrated by a series of examples and comparisons. The code will be open-sourced upon publication.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141144015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
TriClsNet: Surface Reconstruction via Graph-based Triangle Classification TriClsNet：通过基于图形的三角形分类进行曲面重构
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-05-21 DOI: 10.1016/j.cad.2024.103729
Fei Liu, Ying Pan, Qingguang Li
{"title":"TriClsNet: Surface Reconstruction via Graph-based Triangle Classification","authors":"Fei Liu,&nbsp;Ying Pan,&nbsp;Qingguang Li","doi":"10.1016/j.cad.2024.103729","DOIUrl":"10.1016/j.cad.2024.103729","url":null,"abstract":"<div><p>In this paper, we introduce TriClsNet, a novel learning-based network that reconstructs surfaces by reframing the triangle classification problem as a graph node classification problem. An improved graph-based triangle classification module is employed to aggregate information from neighboring triangles, effectively leveraging local neighborhood information and enhancing triangle classification accuracy. Additionally, a self-supervised learning branch is incorporated to predict point cloud normals, aiding our network in better learning local point cloud features. Furthermore, a new loss function is designed to guide our network in effective multi-task learning, encompassing both graph node classification and normal prediction. Comparative experimental results on ShapeNet demonstrate that our method can efficiently perform surface reconstruction, outperforming existing methods in the aspects of preserving surface details, reducing holes, and generalization.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141139115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
MS-GIFT: Multi-Sided Geometry-Independent Field ApproximaTion Approach for Isogeometric Analysis MS-GIFT：等时几何分析的多面几何独立场逼近法
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-05-21 DOI: 10.1016/j.cad.2024.103731
Meng-Yun Wang , Ye Ji , Lin Lan , Chun-Gang Zhu
{"title":"MS-GIFT: Multi-Sided Geometry-Independent Field ApproximaTion Approach for Isogeometric Analysis","authors":"Meng-Yun Wang ,&nbsp;Ye Ji ,&nbsp;Lin Lan ,&nbsp;Chun-Gang Zhu","doi":"10.1016/j.cad.2024.103731","DOIUrl":"10.1016/j.cad.2024.103731","url":null,"abstract":"<div><p>The Geometry-Independent Field approximaTion (GIFT) technique, an extension of isogeometric analysis (IGA), allows for separate spaces to parameterize the computational domain and approximate solution field. Based on the GIFT approach, this paper proposes a novel IGA methodology that incorporates toric surface patches for multi-sided geometry representation, while utilizing B-spline or truncated hierarchical B-spline (THB-spline) basis for analysis. By creating an appropriate bijection between the parametric domains of distinct bases for modeling and approximation, our method ensures smoothness within the computational domain and combines the compact support of B-splines or the local refinement potential of THB-splines, resulting in more efficient and precise solutions. To enhance the quality of parameterization and consequently boost the accuracy of downstream analysis, we suggest optimizing the composite toric parameterization. Numerical examples validate the effectiveness and superiority of our suggested approach.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141139235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Isogeometric Shape Optimization of Reissner–Mindlin Shell with Analytical Sensitivity and Application to Cellular Sandwich Structures 具有分析灵敏度的 Reissner-Mindlin Shell 等几何形状优化及其在蜂窝夹层结构中的应用
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-05-18 DOI: 10.1016/j.cad.2024.103728
Xiaoxiao Du , Jiayi Li , Wei Wang , Gang Zhao , Yazui Liu , Pengfei Zhang
{"title":"Isogeometric Shape Optimization of Reissner–Mindlin Shell with Analytical Sensitivity and Application to Cellular Sandwich Structures","authors":"Xiaoxiao Du ,&nbsp;Jiayi Li ,&nbsp;Wei Wang ,&nbsp;Gang Zhao ,&nbsp;Yazui Liu ,&nbsp;Pengfei Zhang","doi":"10.1016/j.cad.2024.103728","DOIUrl":"10.1016/j.cad.2024.103728","url":null,"abstract":"<div><p>Structural shape optimization plays a significant role in structural design, as it can find an appropriate layout and shape to improve structural performance. Isogeometric analysis provides a promising framework for structural shape optimization, unifying the design model and analysis model in the optimization process. This paper presents an adjoint-based analytical sensitivity for isogeometric shape optimization of Reissner–Mindlin shell structures. The shell structures are modeled by multiple NURBS surfaces and design variables are associated with the position of control points. A multilevel approach is performed with a coarse mesh for the design model and a dense mesh for the analysis model. The sensitivity propagation is achieved through a transformation matrix between the design and analysis models. Structural compliance minimization problems with and without constraints are studied and the optimization history shows that the optimization can converge quickly within fewer iterations. The developed formulations are validated through several numerical examples and applied to the optimization of cellular sandwich structures, which are widely used in engineering applications. Numerical results show that optimized sandwich panels can achieve better performance in bending resistance.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141135663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Splines for Fast-Contracting Polyhedral Control Nets 用于快速收缩多面体控制网的样条线
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-05-11 DOI: 10.1016/j.cad.2024.103727
Erkan Gunpinar , Kȩstutis Karčiauskas , Jörg Peters
{"title":"Splines for Fast-Contracting Polyhedral Control Nets","authors":"Erkan Gunpinar ,&nbsp;Kȩstutis Karčiauskas ,&nbsp;Jörg Peters","doi":"10.1016/j.cad.2024.103727","DOIUrl":"10.1016/j.cad.2024.103727","url":null,"abstract":"<div><p>Rapid reduction in the number of quad-strips, to accommodate narrower surface passages or reduced shape fluctuation, leads to configurations that challenge existing spline surface constructions. A new spline surface construction for fast contracting polyhedral control-nets delivers good shape. A nestedly refinable construction of piecewise degree (2,4) is compared with a uniform degree (3,3) spline construction.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141024875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Collision-free Tool Motion Planning for 5-Axis CNC Machining with Toroidal Cutters 使用环形铣刀进行 5 轴数控加工的无碰撞刀具运动规划
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-05-11 DOI: 10.1016/j.cad.2024.103725
Juan Zaragoza Chichell , Alena Rečková , Michal Bizzarri , Michael Bartoň
{"title":"Collision-free Tool Motion Planning for 5-Axis CNC Machining with Toroidal Cutters","authors":"Juan Zaragoza Chichell ,&nbsp;Alena Rečková ,&nbsp;Michal Bizzarri ,&nbsp;Michael Bartoň","doi":"10.1016/j.cad.2024.103725","DOIUrl":"10.1016/j.cad.2024.103725","url":null,"abstract":"<div><p>Collision detection is a crucial part of CNC machining, however, many state-of-the-art algorithms test collisions as a post-process, after the path-planning stage, or use conservative approaches that result in low machining accuracy in the neighborhood of the cutter’s contact paths. We propose a fast collision detection test that does not require a costly construction of the configuration space nor high-resolution sampling of the cutter’s axis and uses the information of the neighboring points to efficiently prune away points of the axis that cannot cause collisions. The proposed collision detection test is incorporated directly as a part of the tool motion-planning stage, enabling design of highly-accurate motions of a toroidal cutting tool along free-form geometries. We validate our algorithm on a variety of benchmark surfaces, showing that our results provide high-quality approximations with provably non-colliding motions.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141035845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Virtual design of woven fabrics based on parametric modeling and physically based rendering 基于参数建模和物理渲染的编织物虚拟设计
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-04-28 DOI: 10.1016/j.cad.2024.103717
Wentao Deng , Wei Ke , Zhongmin Deng , Xungai Wang
{"title":"Virtual design of woven fabrics based on parametric modeling and physically based rendering","authors":"Wentao Deng ,&nbsp;Wei Ke ,&nbsp;Zhongmin Deng ,&nbsp;Xungai Wang","doi":"10.1016/j.cad.2024.103717","DOIUrl":"https://doi.org/10.1016/j.cad.2024.103717","url":null,"abstract":"<div><p>Textures of woven fabrics are usually designed and produced according to geometric laws in the 2D plane. Physically Based Rendering (PBR) can further optimize and enrich the texture effect, but its application to the more complex 3D structures has been limited. This work reports a method that uses PBR and parametric modeling to construct woven textured materials with centimeter and millimeter level 3D structures. The method can design the structures of various woven fabrics without the need for analyzing the fabric structure details and transfer the inherently iterative work of fabric design to the digital space. The design can be directly applied to mainstream 3D modeling software for virtual presentations in different applications, hence improving the efficiency of woven fabric design and the fidelity of virtual presentation of fabric materials.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140880419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Generation of continuous and sparse space filling toolpath with tailored density for additive manufacturing of biomimetics 生成具有定制密度的连续稀疏空间填充工具路径，用于生物仿生增材制造
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-04-26 DOI: 10.1016/j.cad.2024.103718
Sadaival Singh , Ambrish Singh , Sajan Kapil, Manas Das
{"title":"Generation of continuous and sparse space filling toolpath with tailored density for additive manufacturing of biomimetics","authors":"Sadaival Singh ,&nbsp;Ambrish Singh ,&nbsp;Sajan Kapil,&nbsp;Manas Das","doi":"10.1016/j.cad.2024.103718","DOIUrl":"https://doi.org/10.1016/j.cad.2024.103718","url":null,"abstract":"<div><p>A method of generating a continuous toolpath that can be biased in a user-specified direction of travel is proposed for the fabrication of density-based functionally graded parts through <em>Additive Manufacturing (AM)</em>. The methodology utilizes <em>Lin Kernighan's (LK) Travelling Salesman Problem (TSP)</em> solver over a digitized grid within the contour domain to generate a toolpath with minimal lifts and a common start and end point. Three force-based methods of digitization, namely rectangular, circular, and contour adaptive, are proposed in this work. Each of these methods initialize from a structured or an unstructured grid, where the grid points are assumed to be connected with either linear (rectangular digitization) or a combination of linear and torsional springs (circular and contour adaptive digitization). Enforcing an equilibrium amongst the spring forces and appropriately selecting the ideal spring length, the necessary configuration of grid points can be generated for a desired toolpath.</p><p>The density of grid points (consequently, part density) can be varied through the user-defined input function or an image-based density map imposed on the ideal spring length over the contour domain. The proposed toolpath, as a case study, was implemented for printing a bone with density prescribed through a CT scan image stack. The CT scan of the printed part qualitatively establishes the conformity of the toolpath to the user-specified density gradient.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140894582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Newton Geometric Iterative Method for B-Spline Curve and Surface Approximation 用于 B 样条曲线和曲面逼近的牛顿几何迭代法
IF 4.3 3区 计算机科学
Computer-Aided Design Pub Date : 2024-04-21 DOI: 10.1016/j.cad.2024.103716
Qiuyang Song, Pengbo Bo
{"title":"Newton Geometric Iterative Method for B-Spline Curve and Surface Approximation","authors":"Qiuyang Song,&nbsp;Pengbo Bo","doi":"10.1016/j.cad.2024.103716","DOIUrl":"10.1016/j.cad.2024.103716","url":null,"abstract":"<div><p>We introduce a progressive and iterative method for B-spline curve and surface approximation, incorporating parameter correction based on the Newton iterative method. While parameter corrections have been used in existing Geometric Approximation (GA) methods to enhance approximation quality, they suffer from low computational efficiency. Our approach unifies control point updates and parameter corrections in a progressive and iterative procedure, employing a one-step strategy for parameter correction. We provide a theoretical proof of convergence for the algorithm, demonstrating its superior computational efficiency compared to current GA methods. Furthermore, the provided convergence proof offers a methodology for proving the convergence of existing GA methods with location parameter correction.</p></div>","PeriodicalId":50632,"journal":{"name":"Computer-Aided Design","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140795557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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