Calibration of Measured FRFs Based on Mass Identification Method

It is necessary to calibrate the equipment during each test in modal testing. This paper presented a practical method for the calibration of the measured FRFs based on mass identification method. One advantage of this proposed method is that the calibration is performed directly on the test structure. Thus, it is more reliable and convenient. It is shown that if the mass identification method is applied to the uncalibrated system, a different level between the identified mass and the given exact mass reveals that the set up is not calibrated. And the measured FRFs can be calibrated using the ratio factor of the identified mass and exact mass. The simulation testing demonstrates good performance. In practical testing, however, the accuracy of mass identification results may be vulnerable to the noise and further work is necessary in order to solve this difficulty.