The Digital Upgraded Reconstruction of Ultra-low Frequency Vibration Calibration Standard Apparatus

摘要

The technical indexes of the ultra-low frequency vibration calibration standard apparatus of IEM (Institute of Engineering Mechanics, China Earthquake Administration) are advanced internationally. The apparatus has run for over twenty years and is undergoing the digital upgraded reconstruction now. The paper introduces the working principle and control type of the apparatus, also discusses laser interference technique, multiple feedback technique and digital control technology involved by digital upgraded reconstruction. Furthermore, the paper analyses the parameters calibration method of amplitude-frequency characteristic and phase-frequency characteristic etc on the low frequency vibration sensors, achieves to the object of transferring the vibration value of quantity accurately.