Recent content by Thien

No, it doesn't change the frequency but it changes altitude of the acceleration. But the measurement condition is unchanged.

The acceleration is recorded in z-axis at the same time. To be more clearly, I want to measure precisely acceleration in z-axis at low frequency with a shaker. The accuracy could be less 10%.

Hi Simon! The shaker is excited with a function generator and then the vibrating part is measured with three accelerometer. The ecart type depends on frequency and tension excitation. For example, the Analog device and the laser telemeter has 19% and 200% ecart type at 30Hz and 100Hz, respectively.

I agree with you but I don't have equipment to do that.. Note: the acceleration in Z-axis is useful for my test.

Hi nasu! I carried out two measurements with the same laser telemeter: 1/ displacement measurement then integrated to get acceleration. 2/ acceleration measurement directly. There is a difference between two measurements and this ecart type relative is 27%.

Thank you for your response! Do you mean that the value measured is depend on the position of each accelerometer? I'm not clear about radius and angular velocity which you mentioned, can they be measured?

I use an MEMS accelerometer of Analog Device, a laser telemeter and an PCB piezo accelerometer to measure at harmonic regime. Moreover, the acceleration level is so small about hundreds "mg". It's difficult to calibrate accurately. And I can't find the manufacturers specifications for calibration.

Thank you for your response! So, how can we know which intrument is reliable to calibrate the others? Sincerely

Hi everyone, Is it normal if the acceleration measured is different with different instrumentation? I have measured the acceleration of shaker with three different accelerometer and I didn't obtain the same result. Thanks for your help!