1. Math Data Validation and Auto-Correction at GM using NX Check-Mate
Ubaid U Rehman
General Motors

2. Abstract This presentation will discuss:
The usage of Check-Mate profiles for checking CAD data for conformance to GM Math Data Quality (GM MDQ) and Drafting Standards, and
If non-conformances occur, then auto-correct the non-conformances using GM Standards 2 2

3. General Motors Validation Facts
Check-Mate as globally agreed upon CAD validation tool
Successfully implemented Check-Mate at all GM Global Sites
Enforced 53 Check-Mate Checkers as part of GM workflow
Check-Mate used as CAD Data Assessment Tool
More than 200,000 NX parts assessed weekly using check-mate batch mode
Significant improvement in Math data quality

4. Problem Statement
GM wastes time and money every year due to rework of improper data quality of it’s math files
A large percentage of these problems are caused by non-conformances to GM Math Data Quality (GM MDQ) and Drafting Standards 4 4

5. Math Data Quality Validation
GM is using NX Check-Mate checkers and profiles to check CAD data quality for their adherence to GM standards
Checkers compare the math model to standards and report details that are out of standards 5 5

6. Math Data Quality Validation
After error detection, issues are fixed manually
Manual corrections still cost time and, hence, money 6 6

7. GM Inquire Tool Custom Inquire Tool is used
For searching different object types
To get object information
To highlight/un-highlight
To move objects to different layers 7 7

8. GM Preparation Tool Preparation tool is used
To switch views to wireframe mode
Un-blank objects
Fit and Orient Views
To position WCS to ACS
Sets a flag so that preparation becomes part of workflow
Execute part clean-up

9. Need of Global Math Data Preparation/Auto-Correction Tool
Currently considering combining validation and error corrections in one tool
Check-Mate or separate auto-correction tool?
Eliminate running multiple tools (Inquire and Preparation Tool)
Maintain and enhance one tool only
Cost savings
But with auto-corrections, there is always a big question:
What is safe to auto correct?  9 9

10. Auto Correction Categories
Low Risks
Non Topological
Mostly related to object properties (File Structure)
Layer
Color
Display
Drawing Standards
Part and Object Attributes
View Orientation
High Risks
Modifies Topology
Updates Physical Properties (Mass,Material)
Product and Manufacturing Information

11. Auto-Correcting in Modeling
Low Risk
Auto Correcting in Modeling mode
Organizing modeling object types
Layer / Category
Layer / Entity
Entity / Color
Model View Display
Attributes
Object Display Properties
Blank/Un-Blank
Faces U-V Grids
Non Persistent Customer Defaults

12. Auto-Correcting Drawing Files
Low Risk
Auto Correcting Drawing Entities as per Drawing Standards
Dimension Style
Text Preferences
Centerline Style
Section Line Style
Standard Drawing Notes
Standard Symbols
Drawing 12 12

13. Auto-Corrections Math Data
High Risk
Design-critical geometry that can affect the design intent of the original model
Auto-correcting draft on ribs
Hole position
Part Clean-up
Solid Body Physical Properties
Auto midsurface generation
Product and Manufacturing related
information 13 13

14. GM’s Auto-Corrections Strategy
GM’s strategy for auto-corrections:
For low risk errors
Check-Mate checkers will be allowed to fix problems automatically, with intervention from a designer
For high risk errors
Manual corrections to make sure changes won't affect design intent 14 14

15. Auto-Corrections Strategy
DEMO 15 15

16. Thank You