Article
Computer Science, Software Engineering
Nico Pietroni, Stefano Nuvoli, Thomas Alderighi, Paolo Cignoni, Marco Tarini
Summary: The algorithm presented can generate semi-regular quadrangulation based on line features of an input surface, ensuring accurate representation of feature lines while producing high-quality pure-quad meshes suitable for CAD models. The method is fully automatic and reliable, with minimal assumptions on the input mesh.
ACM TRANSACTIONS ON GRAPHICS
(2021)
Article
Computer Science, Software Engineering
Chi Zhang, Shuangming Chai, Ligang Liu, Xiao-Ming Fu
Summary: The method introduces a novel field-guided segmentation approach and a template-based quad meshing method to generate high-quality quad meshes with a small number of quad patches while bounding geometric errors.
COMPUTER-AIDED DESIGN
(2021)
Article
Computer Science, Software Engineering
Roberto Grosso, Daniel Zint
Summary: The method reconstructs surfaces from volume data using a dual marching cubes approach without lookup tables, generating quad-only meshes that are consistent and watertight. It positions vertices exactly on the surface, uses a halfedge data structure for storage, and processes elements efficiently on GPU. By simplifying patterns to eliminate vertices with valence three, it reduces elements and enhances quality. It describes a CUDA implementation for processing large data sets on GPU at interactive rates, showcasing results on medical and synthetic data.
Article
Automation & Control Systems
Weijia Yao, Bohuan Lin, Brian D. O. Anderson, Ming Cao
Summary: This article introduces a method of moving along an expected path and avoiding collisions in a two-dimensional space using a composite guiding vector field, avoiding the complexity of path planning and map construction, and solving the deadlock problem.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Computer Science, Software Engineering
Heng Liu, David Bommes
Summary: This article investigates the topology of frame fields and derives conditions on their meshability, proposing a novel algorithm to automatically convert non-meshable frame fields into locally meshable ones. Compared to state-of-the-art methods, our algorithm increases the success rate of generating valid integer-grid maps from 2% to 58% on the challenging HexMe dataset.
ACM TRANSACTIONS ON GRAPHICS
(2023)
Article
Computer Science, Software Engineering
Alexander Dielen, Isaak Lim, Max Lyon, Leif Kobbelt
Summary: State of the art quadrangulation methods rely on direction fields to align for parametrization extraction of quad meshes. Lack of user-provided direction information often results in failure to capture structures found in meshes created by experienced designers.
COMPUTER GRAPHICS FORUM
(2021)
Article
Computer Science, Software Engineering
Kacper Pluta, Michal Edelstein, Amir Vaxman, Mirela Ben-Chen
Summary: A new method for computing planar hexagonal meshes is proposed, based on Coordinate Power Fields and an optimization framework, as well as a constraint combination for planar hexagonal meshing addressing challenging meshing problems.
ACM TRANSACTIONS ON GRAPHICS
(2021)
Article
Robotics
Weijia Yao, Hector Garcia de Marina, Zhiyong Sun, Ming Cao
Summary: In this article, the authors propose coordinating guiding vector fields to achieve the simultaneous guidance, navigation, and motion coordination of a team of robots. The desired motion coordination is achieved by controlling virtual coordinates between guiding vector fields. The authors provide rigorous mathematical guarantees for the distributed motion coordination and navigation of robots on paths or surfaces, backed by dynamical systems theory and Lyapunov theory. The proposed algorithm is scalable and validated through simulations and experiments.
IEEE TRANSACTIONS ON ROBOTICS
(2023)
Article
Robotics
Bin-Bin Hu, Hai-Tao Zhang, Weijia Yao, Jianing Ding, Ming Cao
Summary: In this article, a distributed guiding vector-field (DGVF) algorithm is proposed for a team of robots to form a spontaneous-ordering platoon moving along a predefined desired path in the n-dimensional Euclidean space. The algorithm eliminates singular points where vector fields vanish and governs robots to approach a closed and self-intersecting desired path. The interactions among neighboring robots and a virtual target robot enable the realization of the desired platoon with relative parametric displacements achieved in arbitrary ordering sequences. Rigorous analysis guarantees the global convergence of the platoon from any initial positions. Experimental validation and numerical simulations demonstrate the algorithm's effectiveness and robustness.
IEEE TRANSACTIONS ON ROBOTICS
(2023)
Article
Automation & Control Systems
Bin-Bin Hu, Hai-Tao Zhang, Bin Liu, Jianing Ding, Yifan Xu, Chuanshang Luo, Haosen Cao
Summary: This article proposes a distributed guiding-vector-field (DGVF) controller for cross-domain unmanned systems (CDUSs) consisting of heterogeneous unmanned aerial vehicles (UAVs) and unmanned surface vehicles (USVs), to achieve coordinated navigation. The controller decreases communication and computational costs and has been validated through real-lake experiments.
IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Lichi An, Jiabao Li, Yabing Cheng, Yongkang Yu, Xingchen Gu
Summary: In this study, the difference between the meshing of the chain-sprocket and the meshing of the rack-gear in a hybrid vehicle's transmission system was analyzed. By rigidifying the external meshing Hy-Vo chain as a rack, the fluctuation range of the pitch line of the external meshing Hy-Vo chain was analyzed. A design method for the internal-external composite meshing Hy-Vo chain was deduced, and its effectiveness and feasibility were proven through experiments. The study also showed that the description of the internal-external composite meshing in the classical meshing theory is not completely correct.
APPLIED SCIENCES-BASEL
(2023)
Article
Computer Science, Interdisciplinary Applications
Christos Georgiadis, Maxence Reberol, Jean-Francois Remacle
Summary: The pipeline presented in the article focuses on generating quadrilateral meshes on complex geometries, with advantages including reduced element count and alignment with a given direction field. The approach efficiently handles non-manifold feature edges and small features, ultimately producing globally aligned quadrilateral meshes.
ENGINEERING WITH COMPUTERS
(2022)
Article
Physics, Fluids & Plasmas
Alain J. J. Brizard
Summary: This paper investigates the problem of charged-particle motion in crossed electric and magnetic fields and assesses the validity of the guiding-center representation by comparing it with exact particle dynamics. The magnetic field is assumed to be straight and uniform, while the radial electric field is nonuniform. The Hamiltonian guiding-center theory is presented for arbitrary radial electric fields, and explicit examples are given for a linear radial electric field.
PHYSICS OF PLASMAS
(2023)
Article
Computer Science, Software Engineering
Benjamin Jones, Yuxuan Mei, Haisen Zhao, Taylor Gotfrid, Jennifer Mankoff, Adriana Schulz
Summary: We propose an interactive design system for knitting that enables users to create patterns using an industrial knitting machine. Our system allows direct control of key design parameters and ensures consistency and knittability. We demonstrate the effectiveness of our approach through a series of examples.
ACM TRANSACTIONS ON GRAPHICS
(2022)
Article
Environmental Sciences
Tianwen Zhang, Xiaoling Zhang, Xiao Ke
Summary: A novel quad feature pyramid network (Quad-FPN) is proposed for ship detection from synthetic aperture radar (SAR) imagery, with extensive ablation studies conducted to confirm its effectiveness. Experiments on five datasets show Quad-FPN's optimal performance compared to other 12 competitive CNN-based SAR ship detectors. Additionally, satisfactory detection results in actual ship detection further demonstrate Quad-FPN's practical application value in marine surveillance.
Article
Computer Science, Software Engineering
Manish Mandad, Marcel Campen
Summary: The algorithm introduces a high-quality mesh generation method for curvilinear triangulation of planar domains, ensuring the resulting triangular elements meet strict quality measures and bounds, with implications for finite element analysis applications. The boundary of the domain is replicated exactly without geometric approximation errors, achieving reliable results through careful geometric transformations and observations of convergence properties.
ACM TRANSACTIONS ON GRAPHICS
(2021)
Article
Computer Science, Software Engineering
M. Lyon, M. Campen, L. Kobbelt
Summary: The algorithm utilizes a two-stage method for generating quad layouts, involving positioning vertices and connecting them to form layout edges before partitioning the surface into quadrilateral patches. It allows adjustments to the initial layout vertices in the second stage to improve layout quality.
COMPUTER GRAPHICS FORUM
(2021)
Article
Computer Science, Software Engineering
J. Born, P. Schmidt, M. Campen, L. Kobbelt
Summary: The study presents a method for inferring topological information from imperfect input maps, computing homology maps to reliably handle imperfect input, and ensuring compatibility with true homeomorphisms.
COMPUTER GRAPHICS FORUM
(2021)
Article
Computer Science, Software Engineering
Manish Mandad, Ruizhi Chen, David Bommes, Marcel Campen
Summary: Polycube mapping is an approach for generating all-hexahedral meshes with a regular interior. Finding an appropriate polycube domain is challenging, but our novel method solves this problem by solving a series of convex problems, avoiding undesired corners and surface irregularities common to previous methods.
COMPUTER AIDED GEOMETRIC DESIGN
(2022)
Article
Computer Science, Software Engineering
Hendrik Brueckler, Ojaswi Gupta, Manish Mandad, Marcel Campen
Summary: The motorcycle graph, widely used in 2D shape and surface decomposition, has been extended to the three-dimensional volumetric setting, ensuring important decomposition properties. Algorithms are proposed for constructing the 3D motorcycle complex, applied in examples of hexahedral mesh generation and volumetric T-spline construction.
COMPUTER GRAPHICS FORUM
(2022)
Article
Computer Science, Software Engineering
Nico Pietroni, Marcel Campen, Alla Sheffer, Gianmarco Cherchi, David Bommes, Xifeng Gao, Riccardo Scateni, Franck Ledoux, Jean Remacle, Marco Livesu
Summary: In this article, a comprehensive survey of hexahedral mesh generation techniques is provided, covering various approaches, post-processing algorithms, and associated challenges. The discussion also includes recent relaxed approaches for hex-dominant mesh generation. The required background knowledge in geometry and combinatorial aspects is introduced.
ACM TRANSACTIONS ON GRAPHICS
(2023)
Article
Computer Science, Software Engineering
P. Khanteimouri, M. Mandad, M. Campen
Summary: This article presents a reliable method for generating planar meshes of nonlinear rational triangular elements, ensuring their validity and accuracy. The method generalizes existing techniques to handle more complex cases. Experimental results demonstrate the feasibility of this method.
COMPUTER GRAPHICS FORUM
(2022)
Article
Computer Science, Software Engineering
P. Schmidt, J. Born, D. Bommes, M. Campen, L. Kobbelt
Summary: Non-linear optimization is crucial in geometry processing research, but deriving derivatives manually is time-consuming and error-prone. TinyAD, a lightweight C++ library, provides automatic differentiation for geometric problems, making it easier to explore non-linear optimization techniques.
COMPUTER GRAPHICS FORUM
(2022)
Article
Computer Science, Software Engineering
P-A Beaufort, M. Reberol, D. Kalmykov, H. Liu, F. Ledoux, D. Bommes
Summary: HexMe is a dataset consisting of 189 tetrahedral meshes with tagged features and a workflow for their generation. It aims to enable consistent and meaningful evaluation of hexahedral meshing algorithms and techniques, specifically regarding the correct meshing of specified feature points, curves, and surfaces. The meshes are generated with Gmsh from 63 CAD models classified into simple, nasty, and industrial categories. Three types of tetrahedral meshes (uniform, curvature-adapted, and box-embedded) are provided for each CAD model. The mesh generation pipeline is defined using Snakemake, allowing for a fully automated and extensible workflow. The dataset can be downloaded or individual meshes can be selected from the online catalog. HexMe is designed for future developments and hosted on a public GitHub repository for potential contributions and future releases. The value of HexMe is demonstrated by exploring the limitations of a state-of-the-art hexahedral meshing algorithm based on frame fields, achieving varying success rates for meshing feature points, curves, and surfaces.
COMPUTER GRAPHICS FORUM
(2022)
Article
Computer Science, Software Engineering
Maxence Reberol, Kilian Verhetsel, Francois Henrotte, David Bommes, Jean-Francois Remacle
Summary: We propose a robust technique for constructing a topologically optimal all-hexahedral layer on complex model boundaries. The generated boundary layer mesh accurately respects the input surface mesh geometry and optimizes the hexahedral valences of boundary edges. Our approach formulates an integer programming problem based on the duality between boundary hexahedral configurations and disk triangulations. Global optimization is achieved by solving a series of sub-problems using combinatorial branch-and-bound searches. The resulting mesh topology and geometry are automatically generated and fast.
ACM TRANSACTIONS ON MATHEMATICAL SOFTWARE
(2023)
Article
Computer Science, Software Engineering
Martin Heistermann, Jethro Warnett, David Bommes
Summary: Subdividing non-conforming T-mesh layouts into conforming quadrangular meshes is a key task in meshing methods. This paper introduces the Bi-MDF problem and presents an exact solver and an approximate solver for efficiently solving various T-Mesh quantization problems. The exact solver shows significant improvements in runtime and energy compared to the state-of-the-art QuadWild implementation.
ACM TRANSACTIONS ON GRAPHICS
(2023)
Article
Computer Science, Software Engineering
Valentin Z. Nigolian, Marcel Campen, David Bommes
Summary: This paper provides a new framework for volumetric mapping by introducing the concept of progressive expansion. A prototype algorithm is presented for mapping from ball-topology tetrahedral meshes to convex or star-shaped domains, showing improvement in terms of map bijectivity. The framework has the potential to inspire more efficient methods in the future.
ACM TRANSACTIONS ON GRAPHICS
(2023)
Article
Computer Science, Software Engineering
Heng Liu, David Bommes
Summary: This article investigates the topology of frame fields and derives conditions on their meshability, proposing a novel algorithm to automatically convert non-meshable frame fields into locally meshable ones. Compared to state-of-the-art methods, our algorithm increases the success rate of generating valid integer-grid maps from 2% to 58% on the challenging HexMe dataset.
ACM TRANSACTIONS ON GRAPHICS
(2023)
