Unit 1B

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Unit 1B

• Shaker Table Testing

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Shaker Table Test
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Shaker Table Test Diagram
Upcoming units synthesize time history to meet
base input specifications.
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Shaker Table

• The shaker table is electromagnetic.
• Has an armature and a field coil.
• Similar to loudspeaker.

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Shaker Table Testing

• Shaker table testing applies a base excitation to
  the test item.
• Reasons for testing
• 1. Verify the integrity of the design with
  respect to the maximum expected levels.
• 2. Verify parts and workmanship, such as solder
  joints.
• 3. Evaluate circuit board natural frequencies
  and transmissibility ratios.
• 4. Evaluate effectiveness of isolator mounts.

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Design and Verification Tests

• Electronic components should be powered and
  monitored before, during, and after the vibration
  test.
• Some failure modes may be presents only during
  the application of vibration.
• Example, two parallel circuit boards vibrate
  out-of-phase with respect to one another, thereby
  creating an electrical short during vibration.
• Other possible failure modes include misalignment
  or loss of clearance.