History

Consistency and reliability are always major concerns in Computer Aided Design, and integration of CAD files in the manufacturing process.

Companies that furnish electronic product data to Tier-1 & Tier-2 manufacturing suppliers continue to wrestle with this problem. It is a huge head-ache for the tool/mold makers, programmers, engineers and quality control inspectors who must produce products cost effectively, while relying on a variety of different makes and versions of software tools that read these files.

The important question to answer when integrating electronic manufacturing data is, “is the electronic 3D Model that your customer is giving you to produce products from, being imported, opened and read correctly?”

IGES & Step file formats have progressed a long way in offering generic, or neutral file transfer between initial CAD Design platforms and ancillary applications. Sharing data from CAD to CAD, CAD to CAM and CAD to CMM (CAI), or other software tools is usually a hit-or-miss process. The outcome normally needs operator intervention to fix, heal, or tweak a model to make it work right. The problem remains never knowing if ‘the fix” exactly meets the same geometric integrity of the initial file.

Requirements for Exchanging 3D CAD Models

Many large manufacturers are now auditing suppliers and mandating that they provide a means to verify, or validate, that the 3D CAD model they supply, or the “Authority” model, is not corrupted when being read by a 2nd or 3rd party applications. One of these companies is Boeing. Just for this reason established the Boeing D6-51991 “Quality Assurance Standard for Digital Product Definition”. Other large companies are following suit. Even without a mandated requirement, many companies are implementing validation tools to reduce and/or eliminate scrap products that were manufactured using CAD files that were not read correctly and the Authority file data corrupted.

Validation

The specifications of the validation tool, allows the Authority file to compare its geometric form, to post-processed data that has been imported into an application (CAM, CMM software, etc). This data then is exported out and read into a comparative solution program for validation. Another process, within the same program, allows measured data from a CMM to be referenced against the Authority file. Comparevidia is a solution designed to solve the tasks of validating 3D CAD models.

Validation Scenarios

CompareVidia gives a complete, accurate comparison of 3D CAD models with visualization and reporting capabilities.   It uses the most comprehensive comparison techniques to detect all differences between two models.    The validation can be done based on the following criteria:

• Global Validation –   Compare Volume, Surface Area, Center of Mass
• Local Validation –   Finds all entity matches between the two models and finds any deviations between them.
• Topology Validation – Finds topology differences between two models
• Attributes – Provides additional checks for colors, labels, and layers.

Shape differences are analyzed and models are classified as either PASSED or FAILED.  The results are available in the Validation Tree where the user gets complete information about validation of the models.

The differences between models are easily visible in the graphics window.

Face Matching Technology

A unique feature called face matching technology allows CompareVidia to find corresponding surfaces between two models even if one of them is exploded or split into smaller surfaces.  This feature is also used to find corresponding parts in assembly even if the assembly structure does not exist.

Face (1) to Skin (6) classification
Authority Data (CATIA 33 surface) Derivate Data (Translation into SolidWorks 127 surfaces)

CompareVidia detecting 1 surface in CATIA is split into 36 smaller surfaces

Report
A report is automatically generated to digitally certify compliance with a set criteria including Boeing D6-51991 “Quality Assurance Standard for Digital Product Definition”.  It can be stored as pdf, html or text format.

Additional Features

CMM Point Validation

Inspection point data collected from the final real part can be easily compared to the master 3D CAD model in CompareVidia to ensure the product meets the OEM specifications for the automotive and aerospace industry.  CompareVidia provides the following functionality for comparing CMM points:

• Import CMM points using IGES or ASCII files
• Matches CMM points with master model in a well organized project tree
• Records all deviations
• CMM points are colored to show in-tolerance/out-tolerance
• Results saved to report in PDF, HTML, or XML format.

Typical example of a complete validation process used by an aerospace supplier.

Product Manufacturing Information Validation

Most 3D models also contain PMI.   This information is also transferred along with the 3D model. CompareVidia has the capability to validate the PMI information and tell the user if this information has changed as well.

3D Model with PMI
Part Revision Control
CompareVidia is also be used to compare design revisions.   It will identify undocumented changes between design revisions of a CAD model.  The changes are easy to understand and can be stored in the report to communicate with others.

A design change identified, different faces found (purple)

Assembly Revision Control
CompareVidia has the ability to compare complex assembly files to find all differences.    It will detect if there are missing or new parts.  It will also do complete comparison to validate the entire assembly.  All information is stored in the Validation Tree to give you a complete description of all differences.   The results can be saved to a report to communicate with others.

CompareVidia can detect if there are missing or new parts in assembly

Summary
No CAD System Required
CompareVidia is developed using proprietary technology based on Capvidia’s 3DTransVidia Geometry Kernel.  The 3DTransVidia Kernel has been designed over the last 15 years specifically to work with all different CAD systems and all data formats.  This technology provides an extremely accurate, detailed, and truly independent source for comparing models.  CompareVidia is the only product on the market that is not using a CAD system for validation.

For More Information
Measurement Supply Company is a master distributor of Capvidia CAD translation and validation software tools, including Comparevidia. The company principals possess a deep tenure involving the pre and post manufacturing process, including a long history offering Coordinate Measuring Machine, 3D Solid Modeling & Reverse Engineering, Model-Based Inspection tools and CMM Upgrade, Retrofit and Probing solutions. Comparevidia can easily be demonstrated via a web-meeting connected to multiple attendees real-time. To schedule a presentation of Comparevidia or to learn more about us, visit www.measurementsupply.com or call us at 888-502-0220.