Technically, Vis VSA needs two software modules. TeamCenter's Vis Mockup and TeamCenter's Vis VSA. TeamCenter's Vis Mockup handles the base 3D CAD functions, then Vis VSA does the specific Tolerance Analysis "on top of" the Vis Mockup 3D CAD "engine".
All modern 3D tolerance analysis tools are "tied" to some form of 3D CAD engine. But to not be "loyal" to a specific CAD system (i.e., Catia V5, OR UG NX, OR Pro/e), Vis VSA uses TeamCenter's Vis Mockup. Vis Mockup is the
[highlight]"CAD Neutral"[/highlight] solution used in TeamCenter PDM systems to view CAD files from multiple CAD systems.
Using Vis Mockup is advantageous for a few reasons:
1 -
You do not need a dedicated CAD seat to perform tolerance analysis (Vis VSA runs on Windows based PC)
2 -
You do not have to change the master CAD files, when performing
[highlight]"what if"[/highlight] studies, to improve results.
3 -
For companies that run multiple CAD systems, you only need
[highlight]one tool[/highlight] to buy / train staff / schedule work flow through.
4 - Other seemingly "stand alone" 3D tolerance analysis tools have a basic 3D CAD system "built" in. Since many of these products are primary tolerances analysis tools, the 3D CAD portion is limited. TeamCenter's Vis Mockup is improved annually, and get more functions added every year.
5 - if you already have TeamCenter, you have access to all the CAD files from all CAD systems.
6 - If you do not have TeamCenter, then Vis Mockup definitely less expensive to buy than a seat of a major CAD system (see below).
To be "CAD Neutral", this does require some form of translation from the native CAD system into a format that Vis VSA and TeamCenter's Vis Mockup can understand. For the UGS products (i.e., UG NX, IDEAS, SDRC), no special translator is required (see below). For other CAD systems, there are IGES, STEP and ones developed for each specific platform.
Now the JT file format is a "tessellated" file, with NURB data. A "tessellated" file basically is the graphical representation of the CAD file you see on your CAD screen (this is why a hole sometimes looks like an Octagon, instead of a circle). The real "CAD" circle is within the Math on the hard drive, but the octagon is displayed graphically on your screen. Thus when you look at it, it looks incorrect -- but when you query the CAD file, it looks at he hard drive and states this is a circle of XXXXXXXX precision. All modern CAD systems use tessellation, to show graphics quickly on screen.
Most modern CAD files consists of many things - Parametric parameters, NURB data, PMI information, "tessellated" data, and all other types of important stuff. The "tessellated" data is the bulk of the JT file, with the NURB data added for accuracy. For UGS products, the same "tessellation" is used throughout. Thus UG NX a JT files have the same tessellated data. Thus a UG NX file opens directly in Teamcenter products. For all other CAD systems, they use different form of tessellated data, and need to be translated.
Typically, the JT file is 10-20% the size of the original CAD file.
Thus the bottom line -- if you are planning to do 3D tolerance analysis,
do you want to "tie" it to a single CAD system, or one that is can use
multiple CAD systems. Both require a CAD "engine" to run (i.e., Vis Mock, Catia V5, etc.)
Also beware, some "3D" tolerance analysis tools use the 3D CAD system to generate "input" into an analysis tool that generates results outside the 3D environment
in essence, creates a spreadsheet like analysis). This does not allow for true 3D geometry "effects", and may / will give misleading results.
These tools seem "3D", but are more 1D / 2D -ish
[!]Curtis DeSaele[/!]
[blue]Geometric Solutions[/blue] VP Engineering
Dimensional Management Specialists
