Identify the frequency and Grms response of a crystal oscillator mounted in a 6U rack mount electronics module

1. Solidworks Simulation
6U -RF module
vibration analysis
G level response at the location of the
crystal oscillator
D. Blanchet
3B Associates
02-03-13 RA

2. Purpose and Assumptions
• Evaluate the vibration response of a 6U electronics assembly in the
location of the crystal oscillator package using Solidworks FEA
• The input level is random vibration in all 3 axes – 0.04 gsq/hz , 20-
2000 hz
• Geometric input derived from Solidworks 3D model and simplified
• Total weight of the assembly – 4.9 lbs
• Assembly Damping assumption – 10%
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3. Solidworks model view
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4. Solidworks model view
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5. Solidworks model view – crystal package location
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6. Solidworks model for FEA 2 of 4 possible connector
locations used
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P1
P2

7. Solidworks FEA model – mesh
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8. Solidworks FEA model – mesh detail
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9. Solidworks FEA model – restraints > fixed boundary conditions
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10. Solidworks FEA model – Z axis response G’s rms
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Corner point virtual
Accelerometer location

11. Solidworks FEA model – psd response plot in the frequency domain
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34.9 Grms = 104.7 G – 3 sigma

12. Conclusions
• The maximum response at the crystal location is approximately 105
G’s when the unit is under vibration in the z-axis
• Significant enhancements (lowering of the peak G level) can be
accomplished by:
• Relocating the crystal toward the front panel
• Supporting the module in the P2 connector locations
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