CyberOptics AMS-150C, Руководство пользователя

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An AVS unit and another AVS unit will also have identical traces if they are not on resonance. As shown in figure 1
above, the z axis correspondence of an AMS and AVS unit are good but not perfect. The correspondence in the x
and y directions is also very good. So, the z direction correspondence shown above is close to the worst-case
condition.
But, AVS units will not show the same waveform as AMS units if, in one of the cases, a resonance is excited by the
movement.
One potential way to lessen the resonance problem is with acoustic damping. Adding a plate that consists of a
resilient and low density material (foam or rubber) sandwiched between the AVS or AMS housing and another stiff,
high density material will attenuate resonances. The alternating layers of high and low density materials damp the
resonances.
Therefore, when AMS and AVS units are compared against each other there will be some unavoidable differences
caused by the resonances and different housing construction. Resonances cause the largest differences. But even
off resonance there will be some differences between AMS and AVS units.
Both the AMS and AVS units cover the same frequency bandwidth with the same sensitivity. Both are calibrated at
0 Hz and in both units any cross-axis sensitivities are corrected out. Because of the simpler internal structure, the
AVS may have slightly less noise and a cleaner response to a single excitation frequency.