It measures the velocity and frequency of vibration at multiple
points simultaneously of a vibrating target. The output signal
is the velocity vs. time of all the measured points of the target.
How would
I know if the specs of the MB-LDV VibroMet meet my measurement
requirements?
There are
three parameters that define the measurement requirements: 1)
distance to target, 2) frequency of vibration, and 3) velocity
of vibration.
1) Distance to target. The typical range of standoff distances
of the MB-LDV is about 0.5m to 1.5 m or 2m to 6 m. The optical configuration should
be optimized for each standoff distance.
2) Frequency of vibration. The MB-LDV VibroMet can measure frequencies
from 5 Hz to greater than 20 kHz.
3) Velocity of vibration. This parameter has a maximum value of
500 mm/s and may be calculated as follows: V = 2 PI * displacement * frequency.
Can the MB-LDV
VibroMet tolerate changes in signal amplitude, which may occur
when particles or other obscurants block the laser beam?
Yes. The MB-LDV VibroMet measures optical phase changes due to
target vibration. This optical phase change is manifested as a
frequency modulated signal upon mixing the target signal with
the reference beam local oscillator. Thus signal amplitude fluctuations
would have very little effect on the signal frequency provided
that the amplitude of the signal stays above a reasonable threshold.
If the signal amplitude falls below the threshold then the instrument
would experience a "dropout." Our software would look
at regions between dropouts and report the valid data.
How
does the user view the MB-LDV VibroMet output signals?
Due to the large number of simultaneous output signals we provide,
as part of the system, a multi-channel data acquisition system and
custom software to display and analyze all of the signals. Individual
channels can also be viewed on an oscilloscope or spectrum analyzer.
