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In [Part 3 of this series], we set up the kinematic joints for our machine. However, the drivers are currently set to "Constant Velocity," which does not reflect reality.
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Now, we execute the most powerful part of the Digital Twin workflow: injecting our precise timing diagram data from Excel directly into the 3D simulation.
Step 1: Exporting Joint Data to Excel
1. Select the "Graphing" command. This tool is typically used to view results, but we will use it to open the data channel.
2. Select "Spreadsheet". This tells NX to bridge the data into Microsoft Excel.
3. Click OK.
NX will automatically launch Excel. You will see columns for "drv J_Mill" and "drv J_Die" with linear values. These are the default placeholders we created earlier. We must replace these with our optimized curves.
Step 2: Preparing the Data
Pro Tip: Do not edit the raw NX file directly if you are using complex formulas.
4. Save As a new file (e.g., "Calculation_Sheet.xls"). Use this sheet to perform your math, then paste only values back to NX.
Calculating the Indexing Mill (Cycloid):
Since the mill has 16 positions, the displacement per cycle is 360 / 16 = 22.5 degrees. We enter the Cycloid formula here.
Copying the Punch Die Data (Polynomial):
7. Open your previous calculation sheet from [Part 4 - Polynomial Example]. Copy the displacement column.
Step 3: Injecting Data Back to NX
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8. Paste the values into your new calculation sheet.
9. Copy ALL cells (Drivers + Time steps).
10. Switch back to the original "Worksheet in motion" file that NX opened. Select cell A1 and Paste.
11. Click the "Update NX" button (in the Add-Ins menu of Excel).
Step 4: Running the Spreadsheet Simulation
11. Switch back to the UG NX4 Motion Environment.
12. Select the "Spreadsheet Run" command.
13. In the popup, check "Attached". This links the simulation to the active worksheet data.
14. Click Loop and then Play.
You now have a fully functional 3D timing diagram! You can visually inspect for clashes, refine your Excel logic, and re-run the simulation in seconds. This is the essence of Computer-Aided Engineering (CAE) efficiency.
Further Reading on Digital Prototyping:
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