Strange vibration shaker acceleration frequency response test result
Strange vibration shaker acceleration frequency response test result
(OP)
Hi There,
I have a VTS(vibration test system)-100 shaker. To make sure it works correctly, I have done a acceleration frequency response test for the bare shaker. In which, I place an accelerometer on the top of the shaker platform, use a function generator and amplifier to drive the shaker at sweeping frequency from 2 Hz to 6000 Hz. I also use a polytech laser vibrometer to detect the displacement of the point on the shaker platform close to the location of the accelerometer. Attached are my result. From the acceleration frequency response graph, I see several peaks indicating the "resonance" frequency, according to the vibration theory, the acceleration should be a continuous function of the frequency, it should be a smooth line without any resonance peaks. What is wrong with my measurement? or the shaker is bad? I have make sure the accelerometer is good.
Thanks.
Mike
I have a VTS(vibration test system)-100 shaker. To make sure it works correctly, I have done a acceleration frequency response test for the bare shaker. In which, I place an accelerometer on the top of the shaker platform, use a function generator and amplifier to drive the shaker at sweeping frequency from 2 Hz to 6000 Hz. I also use a polytech laser vibrometer to detect the displacement of the point on the shaker platform close to the location of the accelerometer. Attached are my result. From the acceleration frequency response graph, I see several peaks indicating the "resonance" frequency, according to the vibration theory, the acceleration should be a continuous function of the frequency, it should be a smooth line without any resonance peaks. What is wrong with my measurement? or the shaker is bad? I have make sure the accelerometer is good.
Thanks.
Mike





RE: Strange vibration shaker acceleration frequency response test result
I'm not sure what you mean by that. There will be resonance peaks. Is it the sharpness (looks to be discontinuous) of the peaks that bothers you?
RE: Strange vibration shaker acceleration frequency response test result
RE: Strange vibration shaker acceleration frequency response test result
Also it is impossible for the displacement to be flat between 1 and 3 kHz and ththe accelerationa laso to be flat between the same frequency limits.
Cheers
Greg Locock
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RE: Strange vibration shaker acceleration frequency response test result