Phase calibration and correction method for mechanical impedance measurement

[0066] The specific embodiment of the method of the present invention is as follows:

[0067] Take the mechanical impedance test of the BM300 vibration isolator as an example, and use two sets of measurement systems for measurement. Such as image 3 As shown, the first mechanical impedance measurement system uses a 9341B force sensor, a 5015A charge amplifier, a 352C68 acceleration sensor, and a 2694 signal conditioning instrument and data acquisition instrument for measurement, such as Figure 4 As shown, the second mechanical impedance measurement system uses ICP type 288D01 impedance head and 2694 signal conditioning instrument, and 2694 type signal conditioning instrument and data acquisition instrument for measurement.

[0068] Such as Figure 5 to Figure 8 As shown, the test results of the axial input mechanical impedance of the vibration isolator under no-load measured by two different measurement systems, where Figure 8 There is a significant difference in the phase characteristics of the mechanical impedance of Figure 5 and Image 6 In, there are also differences in the real and imaginary parts reflecting the phase, such as Picture 9 As shown, the figure shows the amplitude-phase calibration result of the first mechanical impedance measurement system, Picture 9 9-1 represents the frequency-varying transfer function amplitude between the force sensor 3 and the acceleration sensor 1 test channel when the first mechanical impedance measurement system is used for calibration, and 9-2 represents the force vs. The amplitude deviation between accelerations, 9-3 represents the phase deviation between force and acceleration when the first mechanical impedance measurement system is used for calibration. Such as Picture 10 As shown, the figure shows the amplitude-phase calibration result of the second mechanical impedance measurement system, where Picture 10 10-1 represents the frequency-dependent transfer function amplitude between the force sensor 3 and the acceleration sensor 1 when calibrated by the second mechanical impedance measurement system, and 10-2 represents the force and The amplitude deviation between accelerations, 10-3 represents the phase deviation between force and acceleration when the second mechanical impedance measurement system is used for calibration. Combine the above Figure 5 to Figure 8 ,as well as Picture 9 , Picture 10 , It can be judged that there is an error between the mechanical impedance measured by the two measurement systems. The error is caused by the amplitude and phase deviation between the measurement channels, and the amplitude and phase need to be corrected.

[0069] use Picture 9 and Picture 10 Amplitude and phase calibration results, the mechanical impedance test results of the BM300 vibration isolator are corrected, using the method of the present invention, the corrected mechanical impedance characteristic results obtained by the first mechanical impedance measurement system and the second mechanical impedance measurement system are shown in Figure 11 to Figure 14 Through comparison, it can be seen that after the mechanical impedance tested by the method of the present invention is corrected, the mechanical impedance obtained by the first mechanical impedance measurement system and the second mechanical impedance measurement system are relatively close, and the amplitude, phase, real and imaginary impedance The parts tend to be consistent, and the impedance phase deviation is greatly reduced.