Vibration Simulation
Laboratory evaluation of electronic and mechanical assemblies relies on controlled mechanical excitation to simulate operational environments. Conducting electrodynamic shaker testing exposes components to defined frequency profiles, including random, sinusoidal, or shock accelerations. This method utilizes an electromagnetic coil to drive an armature and transfer mechanical energy to the test fixture.
Testing Procedure
The test specimen is securely bolted to a rigid expansion table or slip plate connected to the shaker armature. During electrodynamic shaker testing, control accelerometers placed on the fixture feed signal data back to the controller to adjust the drive signal in real-time. This closed-loop control ensures that the specimen experiences the exact acceleration profile specified by the testing standard.
The system software continuously calculates the transfer function to compensate for the mechanical impedance of the load.
Calibration Benchmark
Laser vibrometers or reference accelerometers calibrate the shaker table surface before securing the test load. This procedure verifies that the electrodynamic shaker testing setup maintains a uniform acceleration distribution across the mounting surface. The calibration process checks for cross-axis motion to ensure the excitation remains uniaxial.
Resonant Response
Structural weakness or mounting flaws become apparent when the excitation frequency matches the natural frequency of the specimen. Performing electrodynamic shaker testing allows engineers to identify these resonance points and modify the structural design to shift them outside the operating range. This step prevents premature fatigue failure during field operation.
