Sine Sweep Vibration Testing Primer. Eric Sauther OPT521 Optomechanics Fall 2013. Why do we do a Sine Sweep Vibration Test?. Part Responses to a Sine Wave Input are important to characterize a part/assembly for several reasons: Characterize Model Response Endurance Limits of Part(s)
OPT521 Optomechanics Fall 2013
Types of Sine Sweeps
Typical Sine Sweep is a linear input
The Sinusoidal Signal input can be customized:
Non-Linear Sine frequency Change inputs are used if you want to spend less time testing at a certain frequency or range of frequencies for pragmatic reasons
Displacement, Velocity, Help define your input signal normally shown as Acceleration
Calculated Response (Transmissibility) Relative to Q factor
Sine Sweep Signal Response
Digging further we know that Part under test will have a response through a range of frequencies through the Transmissibility relationship
Ramping of Acceleration
MAX G Allowed
Test Response of Two metal bars at different Lengths
Knowing this we can set a pre-determined Sine Sweep signal Input to the part under test.
We “Plateau” the area of interest in order to better further investigate the response area, and to have a Factor of Safety for the Acceleration input.
Response at Resonance
LET US NOT BREAK OUR PART
One Example of Vibration table offering a Single DOF vibration Axis
Example of a Slip Table
Things to note in Table setup
Control accel should be on the farthest edge of the table and as close as possible to the product.
Multiple Control Accels can be used and Averaged.
Accel should be Tri-axial in configuration
Table should already be characterized with support fixture
Software by Unholtz-Dickie Corporation VWIN IIVibration Control & Analysis System
Simply an Octave is a doubling of the Frequency limits (think musical instruments).