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A system for constructing boundary representation solid models from a two-dimensional sketch

P.A.C. Varley, R.R. Martin
2000 Proceedings Geometric Modeling and Processing 2000. Theory and Applications  
This paper describes a system which converts a twodimensional sketch with hidden lines removed of a single polyhedral object into a boundary representation solid model.  ...  The system improves on a previous system by Grimstead by analysing the sketch for symmetry elements and regularities.  ...  Acknowledgements The authors are grateful to Unigraphics Solutions Inc. for providing Parasolid to the authors for use in this research.  ... 
doi:10.1109/gmap.2000.838235 dblp:conf/gmp/VarleyM00 fatcat:mjuuof5aurby5d5y5rwz55tzcm

Digital clay: deriving digital models from freehand sketches

Eric Schweikardt, Mark D. Gross
2000 Automation in Construction  
We are exploring two methods for generating three-dimensional coordinates from a sketch.  ...  Before Digital Clay derives a three-dimensional coordinate system from the two-dimensional projection, the constituent lines of the latched sketch must be rectified in order to accurately represent a correct  ... 
doi:10.1016/s0926-5805(99)00052-7 fatcat:3e2kynn7izanpgplovezyoicpi

A design-through-analysis approach using the Finite Cell Method (ECCOMAS Congress 2016) [article]

Benjamin Wassermann, Tino Bog, Stefan Kollmannsberger, Ernst Rank
2018 arXiv   pre-print
Modern 3D Computer-Aided-Design (CAD) systems use mainly two types of geometric models.  ...  Alternatively, objects may be represented by Constructive Solid Geometry (CSG), which is strongly related to Procedural Modeling (PM).  ...  Many modern CAD systems use a hybrid representation combining B-Rep and constructive solid geometry (CSG) [7] .  ... 
arXiv:1809.09942v1 fatcat:ehwcejaze5hipcv47lijnwwudy

Surface patches from unorganized space curves

Fatemeh Abbasinejad, Pushkar Joshi, Nina Amenta
2012 Proceedings of the 2012 symposuim on Computational Geometry - SoCG '12  
Figure 1 : Our system takes as input a wireframe model produced from a 3D curve sketch, and outputs a set of curved surface patches representing the object.  ...  Abstract Recent 3D sketch tools produce networks of three-space curves that suggest the contours of shapes. The shapes may be non-manifold, closed three-dimensional, open two-dimensional, or mixed.  ...  We thank Dan Anthony Alcantara for help with the video, Dmitry Morozov for topological advice, and Daniel Presedo from the Photoshop group at Adobe for doing the informal evaluation.  ... 
doi:10.1145/2261250.2261314 dblp:conf/compgeom/AbbasinejadJA12 fatcat:uzqsbzktrjaevbsf2ypoty5o5y

Surface Patches from Unorganized Space Curves

Fatemeh Abbasinejad, Pushkar Joshi, Nina Amenta
2011 Computer graphics forum (Print)  
Figure 1 : Our system takes as input a wireframe model produced from a 3D curve sketch, and outputs a set of curved surface patches representing the object.  ...  Abstract Recent 3D sketch tools produce networks of three-space curves that suggest the contours of shapes. The shapes may be non-manifold, closed three-dimensional, open two-dimensional, or mixed.  ...  We thank Dan Anthony Alcantara for help with the video, Dmitry Morozov for topological advice, and Daniel Presedo from the Photoshop group at Adobe for doing the informal evaluation.  ... 
doi:10.1111/j.1467-8659.2011.02012.x fatcat:hzgidnz33rghhbqjmfz5hmbm74

From geometric design to numerical analysis: A direct approach using the Finite Cell Method on Constructive Solid Geometry

Benjamin Wassermann, Stefan Kollmannsberger, Tino Bog, Ernst Rank
2017 Computers and Mathematics with Applications  
In contrast to IGA, which deals with boundary represented models (B-Rep), our approach focuses on parametric volumetric models such as Constructive Solid Geometries (CSG).  ...  During the last ten years, increasing efforts were made to improve and simplify the process from Computer Aided Design (CAD) modeling to a numerical simulation.  ...  Nowadays, 3D CAD systems are usually based on either (i) boundary representation or (ii) procedural modeling with solid primitives.  ... 
doi:10.1016/j.camwa.2017.01.027 fatcat:yv5im47obrbjznjotlxafgkvzu

Standardized data exchange of CAD models with design intent

Junhwan Kim, Michael J. Pratt, Raj G. Iyer, Ram D. Sriram
2008 Computer-Aided Design  
Modern CAD systems generate feature-based product shape models with parameterization and constraints.  ...  These standards ignored the construction history, parameters, constraints, features and other elements of 'design intent' present in the model to be transferred.  ...  ISO 10303-111 ('Elements for the procedural representation of solid shapes') [7, 19] , provides representations of operations for the construction of feature-based solid models.  ... 
doi:10.1016/j.cad.2007.06.014 fatcat:ogq6xpdnbzco5hk5vvzvtpjewe

A set of standard modeling commands for the history-based parametric approach

Duhwan Mun, Soonhung Han, Junhwan Kim, Youchon Oh
2003 Computer-Aided Design  
The second is a procedural approach based on the sequence of operations issued to construct the models.  ...  There are two approaches for the exchange of design intents such as parameters, features, and constraints.  ...  -Structures from STEP Part 42 ed.2 for exchange of CSG (constructive solid geometry), manifold B-Reps and other solids.  ... 
doi:10.1016/s0010-4485(03)00022-8 fatcat:cqp22gnzr5cq5l6cij3q5tiy6q

Maintenance of Geometric Representations Through Space Decompositions

Vadim Shapiro
1997 International journal of computational geometry and applications  
The ability to transform between distinct geometric representations is the key to success of multiple-representation modeling systems.  ...  But the existing theory of geometric modeling does not directly address or support construction, conversion, and comparison of geometric representations.  ...  But not every set constructed from polynomial equalities and set operations is a boundary of a solid.  ... 
doi:10.1142/s0218195997000041 fatcat:loaqa7giafbsbemgdbxue5ysay

Integration of Explicit Geometric Constraints in the Comparison of 3D CAD Models for Part Design Reuse [chapter]

Antoine Brière-Côté, Louis Rivest, Roland Maranzana
2012 IFIP Advances in Information and Communication Technology  
We have developed a 3D CAD model comparison method focused on the representation of shape differences between similar models with respect to the reference's geometric constraints.  ...  While shape-based retrieval techniques contribute to the part design reuse process by retrieving similar part models, selecting the optimal candidate for reuse remains a challenge.  ...  the information from the calculation phase to construct a difference model (∆) designed for subsequent analysis and manipulation.  ... 
doi:10.1007/978-3-642-35758-9_40 fatcat:ni7oumsem5evvn6jvl5nkohclm

Fundamental Techniques for Geometric and Solid Modeling [chapter]

CHRISTOPH M. HOFFMANN, GEORGE VANĚČEK
1991 Control and Dynamic Systems  
We review traditional and novel paradigms for representing solids and interrogating them. The traditional paradigms reviewed are the boundary, constructive, and spatial subdivision representations.  ...  Finally, we review some algorithms for two-dimensional mesh generation based on the skeleton.  ...  Pottmann for bringing the work on cyclographic maps to our attention, and to R. Lynch, who noted the connection between offsets and the Hamilton-Jacobi equations.  ... 
doi:10.1016/b978-0-12-012748-1.50009-4 fatcat:z2lkxsca2rfavoymg6rbwesmpa

Information Structures and Database Support for Solid Modeling [chapter]

Th. Härder, Ch. Hübel, B. Mitschang
1989 Theory and Practice of Geometric Modeling  
Starting from analytical representations based on analytical methods we discuss the use of constructive solid geometry and boundary representation models with various refinements.  ...  Our DBMS architecture consists of a neutral kernel part running on a server machine and an application layer tailored to solid modeling tasks which together with the application, i.e. the solid modeler  ...  Boundary Representation Scheme An other example of a commonly used solid representation scheme is called boundary representation (BREP).  ... 
doi:10.1007/978-3-642-61542-9_27 fatcat:2qnwivtyvfbkzee5ptnkf5pv6a

Multi-Scale Geometric-Semantic Modeling of Shield Tunnels for GIS and BIM Applications

A. Borrmann, T.H. Kolbe, A. Donaubauer, H. Steuer, J.R. Jubierre, M. Flurl
2014 Computer-Aided Civil and Infrastructure Engineering  
To meet this demand, this paper presents a comprehensive concept for incorporating multi-scale representations with building information models, with a particular focus on the geometric-semantic modeling  ...  On the one hand this implies the utilization of both, Geographic Information Systems (GIS) as well as Building Information Modeling (BIM) tools, for performing the required analysis, modeling, and visualization  ...  A tunnel model in LoD1 consists of a boundary representation of the tunnel volume without any further semantic classification. Its geometry must be a solid resulting from a vertical extrusion.  ... 
doi:10.1111/mice.12090 fatcat:dg3pmf2vdnggzn3oqrpgbcepmq

Two-Dimensional Selections for Feature-Based Data Exchange [chapter]

Ari Rappoport, Steven Spitz, Michal Etzion
2006 Lecture Notes in Computer Science  
The general algorithm operates at a geometric level and does not require solving the persistent naming problem, which is required for selection support inside a single CAD system.  ...  In this paper we address two-dimensional selections (faces and surfaces) in feature-based data exchange (FBDE).  ...  The Proficiency UPR implementation is a collective effort of the Proficiency development team, headed by Alex Tsechansky.  ... 
doi:10.1007/11802914_23 fatcat:hy7ru54vhjgttma6hv5pl35vxi

Generation of Computational 3D Models of Human Bones Based on STL Data and CAD Software Packages

Dan Leordean, Cristian Vilău, Mircea Cristian Dudescu
2021 Applied Sciences  
For converting the STL models, specific approximation functions from CATIA and Creo Parametric software were used as well as 3D solid modeling methods that used sketches drawn for sections of the specific  ...  This conversion is required to get a solid 3D model that can be used for finite element analysis and to be processed using Boolean functions in specific CAD programs.  ...  After that, a sketch in the section plane was created (see Figure 10b ). The sketch is required for the reunion of the two components after the conversion into parametric solids.  ... 
doi:10.3390/app11177964 fatcat:vmlovgi5vra55kxkpihoiqyxiy
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