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Solid modelling (or modeling) is the unambiguous representation of the solid parts of an object, that is, models of solid objects suitable for computer processing. It is also known as volume modelling. Other modelling methods include surface models (used extensively in automotive and consumer product design as well as entertainment animation) and wire frame models (which can be ambiguous about solid volume). Freeform surface, or Freeform Surfacing used in CAD and other computer graphics software are used to describe the skin of a 3D geometric element. ...
A wire frame model is a visual presentation of an electronic representation of a three dimensional or physical object used in 3D computer graphics. ...
Primary uses of solid modelling are for CAD, engineering analysis, computer graphics and animation, rapid prototyping, medical testing, product visualization and visualization of scientific research. CAD redirects here. ...
Engineering is the application of scientific and technical knowledge to solve human problems. ...
Computer graphics (CG) is the field of visual computing, where one utilizes computers both to generate visual images synthetically and to integrate or alter visual and spatial information sampled from the real world. ...
12 frames per second is the typical rate for an animated cartoon. ...
To meet Wikipedias quality standards, this article or section may require cleanup. ...
Product Visualization involves visualization software technology for the viewing and manipulation of 3D models, technical drawing and other related documentation of manufactured components and large assemblies of products. ...
Visualization can refer to: Graphic Visualization as in any technique for creating images, diagrams, or animations to communicate any message. ...
Basic theoretical concepts
- Sweeping
- An area feature is "swept out" by moving a primitive along a path to form a solid feature. These volumes either add to the object ("extrusion") or remove material ("cutter path").
- Also known as 'sketcher based modelling'.
- Analogous to various manufacturing techniques such as extrusion, milling, lathe and others.
- Parameterized primitive instancing.
- An object is specified by reference to a library of parameterized primitives.
- For example, a bolt is modelled for a library, this model is used for all bolt sizes by modifying a set of its parameters.
- Spatial occupancy (voxel)
- The whole space is subdivided into regular cells, and the object is specified by the set of cells it occupies.
- Models described this way lend themselves to Finite difference analysis.
- This is usually done after a model is made, as part of automated pre-processing for analysis software.
- Facet modeling
- Forming the outside surface form of the volume from any triangular planes
- Often used in reverse engineering of physical models.
- Decomposition
- Similar to "spatial occupancy", but the cells are neither regular, nor "prefabricated".
- Models described this way lend themselves to FEA.
- This is usually done after a model is made, as part of automated pre-processing for analysis software.
- Feature based modelling
- Complex combinations of objects and operators are considered together as a unit which can be modified or duplicated.
- Order of operations is kept in a history tree, and parametric changes can propagate through the tree.
- Parametric modelling
- Attributes of features are parameterized, giving them labels rather than only giving them fixed numeric dimensions, and relationships between parameters in the entire model are tracked, to make changing numeric values of parameters easier.
- Almost always combined with features, giving parametric feature based modelling.
Extrusion is a manufacturing process where a material, often in the form of a billet, is pushed and/or drawn through a die to create long objects of a fixed cross-section. ...
A Miller is a person who operates a mill for grinding material and usually refers to one who grinds a cereal crop to make flour. ...
Conventional metalworking lathe In woodturning, metalworking, metal spinning, and glassworking, a lathe is a machine tool which spins a block of material so that when abrasive, cutting, or deformation tools are applied to the block, it can be shaped to produce an object which has rotational symmetry about an axis...
In computer-aided design, the term boundary representation — often abbreviated as B-REP or BREP, refers to storing information about how to make a model based on its geometric and often Euler topological boundaries. ...
Injection molding can be used to make plastic artificial flowers such as these. ...
One half of a bronze mold for casting a socketed spear head dated to the period 1400-1000 BC. This article is about the manufacturing process; for other uses, see Casting (disambiguation). ...
A vacuum/pressure assist thermoforming machine with molds visible in the lower right. ...
A voxel (a portmanteau of the words volumetric and pixel) is a volume element, representing a value in three dimensional space. ...
In mathematics, a finite difference is like a differential quotient, except that it uses finite quantities instead of infinitesimal ones. ...
Facets are flat faces on geometric shapes. ...
Visualization of how a car deforms in an asymmetrical crash using finite element analysis. ...
Constructive solid geometry (CSG) is a technique used in solid modeling. ...
A parametric feature based modeler is a CAD/Constructive Solid Geometry modeler that allows a user to refer to features instead of the underlying geometry. ...
History Solid modeling has to be seen in context of the whole history of CAD, the key milestones being the development of Romulus which went on to influence the development of Parasolid and ACIS and thus the mid-range Windows based feature modelers such as SolidWorks and Solid Edge and the arrival of parametric solid models system like T-Flex and Pro/Engineer. CAD is a TLA that may stand for: Cadiz Railroad (AAR reporting mark CAD) Canadian dollar – ISO 4217-code Capital Adequacy Directive Card Acceptance Device Children of the Anachronistic Dynasty Computer-aided design Computer-aided detection (medical) Computer-aided diagnosis (medical) Computer-assisted dispatch Computer-assisted drafting Coronary artery disease...
This page is a candidate for speedy deletion, because: External Link Only If you disagree with its speedy deletion, please explain why on its talk page or at Wikipedia:Speedy deletions. ...
Acis was, in Greek mythology, a Sicilian youth who was often considered the son of Dionysus. ...
Practical applications
Parametric Solid modelling CAD Solid modellers have become commonplace in engineering departments in the last ten years due to faster PCs and competitive software pricing. They are the workhorse of machine designers.
Solid modelling software creates a virtual 3D representation of components for machine design and analysis. Interface with the human operator is highly optimized and includes programmable macros, keyboard shortcuts and dynamic model manipulation. The ability to dynamically re-orient the model, in real-time shaded 3-D, is emphasized and helps the designer maintain a mental 3-D image.
Design work on components is usually done within context of the whole product using assembly modelling methods. Assembly Modelling is technology and methods used by Computer-aided design and Product visualization computer software systems to handle multiple files that represent components within a product. ...
A solid model generally consists of a group of features, added one at a time, until the model is complete. Engineering solid models are built mostly with sketcher-based features; 2-D sketches that are swept along a path to become 3-D. These may be cuts, or extrusions for example. Image File history File links Cad-fm01s. ...
Another type of modelling technique is 'surfacing' (Freeform surface modelling). Here, surfaces are defined, trimmed and merged, and filled to make solid. The surfaces are usually defined with datum curves in space and a variety of complex commands. Surfacing is more difficult, but better applicable to some manufacturing techniques, like injection molding. Solid models for injection molded parts usually have both surfacing and sketcher based features. Freeform surface modelling is the art of engineering Freeform Surfaces with a CAD or CAID system. ...
Engineering drawings are created semi-automatically and reference the solid models. An engineering drawing is a type of drawing that is technical in nature, used to fully and clearly define requirements for engineered items, and is usually created in accordance with standardized conventions for layout, nomenclature, interpretation, appearance (such as typefaces and line styles), size, etc. ...
The learning curve for these software packages is steep, but a fluent machine designer who can master these software packages is highly productive.
The modelling of solids is only the minimum requirement of a CAD system’s capabilities. CAD redirects here. ...
Parametric modelling uses parameters to define a model (dimensions, for example). The parameter may be modified later, and the model will update to reflect the modification. Typically, there is a relationship between parts, assemblies, and drawings. A part consists of multiple features, and an assembly consists of multiple parts. Drawings can be made from either parts or assemblies.
Example: A shaft is created by extruding a circle 100 mm. A hub is assembled to the end of the shaft. Later, the shaft is modified to be 200 mm long (click on the shaft, select the length dimension, modify to 200). When the model is updated the shaft will be 200 mm long, the hub will relocate to the end of the shaft to which it was assembled, and the engineering drawings and mass properties will reflect all changes automatically.
Examples of parameters are: dimensions used to create model features, material density, formulas to describe swept features, imported data (that describe a reference surface, for example).
Related to parameters, but slightly different are Constraints. Constraints are relationships between entities that make up a particular shape. For a window, the sides might be defined as being parallel, and of the same length.
Parametric modelling is obvious and intuitive. But for the first three decades of CAD this was not the case. Modification meant re-draw, or add a new cut or protrusion on top of old ones. Dimensions on engineering drawings were created, instead of shown.
Parametric modelling is very powerful, but requires more skill in model creation. A complicated model for an injection molded part may have a thousand features, and modifying an early feature may cause later features to fail. Skillfully created parametric models are easier to maintain and modify. Injection molding is a manufacturing technique for making parts from plastic material. ...
Parametric modelling also lends itself to data re-use. A whole family of capscrews can be contained in one model, for example.
Entertainment Animation of a computer generated character is an example of parametric modelling. Jar Jar Binks is described by parameters which locate key body positions. The model is then built off these locations. The parameters are modified, and the model rebuilt, for each frame to create animation. Jar Jar Binks (born c. ...
12 frames per second is the typical rate for an animated cartoon. ...
Medical solid modelling Modern computed axial tomography and magnetic resonance imaging scanners can construct solid models of interior body features. CT apparatus in a hospital Computed axial tomography (CAT), computer-assisted tomography, computed tomography, CT, or body section roentgenography is the process of using digital processing to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around...
Magnetic Resonance Image showing a vertical (sagittal) cross section through a human head. ...
Uses of medical solid modelling;
- Visualization
- Visualization of specific body tissues (just blood vessels and tumor, for example)
- Creating solid model data for rapid prototyping (to aid surgeons preparing for difficult surgeries, for example)
- Combining medical solid models with CAD solid modelling (design of hip replacement parts, for example)
To meet Wikipedias quality standards, this article or section may require cleanup. ...
CAD is a TLA that may stand for: Cadiz Railroad (AAR reporting mark CAD) Canadian dollar – ISO 4217-code Capital Adequacy Directive Card Acceptance Device Children of the Anachronistic Dynasty Computer-aided design Computer-aided detection (medical) Computer-aided diagnosis (medical) Computer-assisted dispatch Computer-assisted drafting Coronary artery disease...
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