High End CAD/CAM Packages: Parametric Modelling packages dominate the high end market, such as Pro/Engineer, Unigraphics and CATIA. Parametric modelling i

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High End CAD/CAM Packages:

Parametric Modelling packages dominate the high end market, such as Pro/Engineer, Unigraphics and CATIA. Parametric modelling is basically explained as; rather than models being constructed like a blob of plasticine, with bits being added or removed to make changes, the user constructs a list of features or parts, which are stored by the program and can be used to change the model by rebuilding it with modified parameters. Parts drawn and saved are imported into an assembly where they are mated or constrained to build complex assemblies.

One feature that seperates the high end packages to the mid range is how the programs have evolved, programs such as SolidWorks, Inventor, and Solid Edge have always run on Windows and as a result haven't had major changes to their user interfaces. But high-end programs such as the ones mentioned above have undergone major interface overhaul, a result of migrating from UNIX-based systems.

Unigraphics or as it’s known now NX (due to the company acquiring and merging with a package called I-deas, which is a styling product capabable of  suitable automotive surfacing applications), is a parametric modelling package with CAM capabilities. 

NX is widely used throughout the engineering industry, especially in the automotive and aerospace sectors. This is due its ability do generate a model parametrically then transferring this into a CNC simulation program called Vericut, this is extremely important in the rapid prototyping stage of manufacture.

NX’s latest release NX 3 has had many interface updates with new icons and a new arrangement, but more importantly, individual tools work differently. NX 3 users can now dynamically drag when performing operations such as extruding and filleting, which speeds up conceptual design. Also, it's now easier to access other techniques for determining values, such as measuring an existing distance, picking a previously used dimension. This is extremely important in reverse engineering in particular.

NX 3 could still be improved to help the modelling workflow. For instance, users can't extrude or revolve without first having a pre-drawn sketch.

Pro/Engineer is also a parametric feature-based 3D Solid modelling CAD package, it is a mechanical design tool and is used for creating very complex 3D models, Pro/Engineer was the pioneer of parametric modelling and its user interface was not Windows based but has been converted in recent years to comply, this initially caused some issues but most have been eradicated now.

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Pro/Engineer functions consist of solid model data for tooling and rapid prototyping, CNC manufacturing, finite element analysis, engineering drawings, and revision control information. It is available for various Unix-variants, Windows and Linux. All data is exchangeable between these platforms with no need for conversion.

Pro/Engineer offers its Advanced Rendering system where you can quickly create realistic product images, enabling richer marketing material and more compelling design reviews.

Pro/Engineer also uses Pro/Concept where you can directly export designs to rapid prototype machines, or to CAD solutions for refinement.

CATIA is the high end Parametric CAD/CAM package marketed by IBM. ...

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