Analysis of vibration characteristics for cam absolute gravimeter via improved MEEMD-HHT method

An accurate determination of gravitational acceleration has been playing an important role in the areas of metrology, geophysics, and geodetics. Vibration interference is the main factor affecting the accuracy of absolute gravity measurement based on optical interferometry. A novel research on vibration characteristics for cam absolute gravimeter was proposed with the improved MEEMD-HHT method. After the adaptive decomposition of the measured signal, the vibration data was analyzed and studied with the time-frequency spectrum and energy spectrum. Experimental results show that this method can restrain mode mixing effectively, and accurately obtain the energy distribution of each frequency band of vibration. This research can improve the accuracy of absolute gravity measurement and lay the foundation for the design of high-precision vibration absorber.