An atomic interference gravimeter (AIG) is of great value in underwater aided navigation, but one of the constraints on its accuracy is vibration noise. For this reason, technology must be developed for its vibration isolation. Up to now, three methods have mainly been employed to suppress the vibration noise of an AIG, including passive vibration isolation, active vibration isolation and vibration compensation. This paper presents a study on how vibration noise affects the measurement of an AIG, a review of the research findings regarding the reduction of its vibration, and the prospective development of vibration isolation technology for an AIG. Along with the development of small and movable AIGs, vibration isolation technology will be better adapted to the challenging environment and be strongly resistant to disturbance in the future.

The atom gravimeter is a novel type of gravimeter that offers notable advantages, including high sensitivity and long-term stability. However, the accuracy and reliability of measurements obtained from atom gravity measurement systems are significantly influenced by vibrations. To address this issue, this paper presents the design and development of an active and passive vibration isolation system aimed at reducing vibrations affecting the Raman mirror during dynamic measurements in atom gravimeters. The system is based on the passive vibration isolation platform. To meet the vertical vibration isolation requirements of the atom gravimeter and to be applicable in dynamic measurement applications, linear bearings are utilized to restrict the horizontal movement of the vibration isolation platform while allowing linear movement in the z-axis direction. This effectively enhances the vibration isolation performance in the vertical direction. Additionally, three voice coil motors are evenly distributed on the vibration isolation platform at 120° intervals to prevent system instability and inclination caused by uneven force. Furthermore, a control strategy that combines adaptive feedforward control and PID feedback control is implemented to further improve the vibration isolation performance of the system. Experimental results demonstrate that the maximum vibration in the vertical direction can be suppressed by 98.34% in the frequency band below 10Hz, which is particularly sensitive to the atom interferometer. The impact of vibration on the sensitivity of the cold atom gravimeter is two orders of magnitude lower than that experienced on the ground, significantly enhancing the accuracy of the atom gravimeter. These findings have substantial practical value and can be applied in scientific research and industrial applications within the field of atomic gravity measurement. They provide positive implications for the development of advanced dynamic measurement techniques for atom gravimeters.

The atomic interference gravimeter, characterized by its high sensitivity and precision in gravity measurement, is significantly influenced by vibration noise in field environments. The vibration correction is a feasible approach to mitigate the constraints imposed by vibration noise in measurements, thereby enhancing accuracy. The vibration noise of the shipborne environment is intensified, leading to the complete disruption of the traditional chirp fringes. We analyzed the correlation between the vibration phase and atom population and developed an acceleration phase fringe that is suitable for the shipborne environment. Subsequently, to enhance the precision of calibrating the transfer function resulting from the inconsistency between the centers of the accelerometer mass and the Raman reflecting mirror, we proposed a second-order coupling acceleration transfer model as a substitute for the tradition model. An intelligent optimization algorithm was employed to optimize the model parameters. Finally, an atomic gravimeter system was constructed to assess the proposed model and method in the context of shipborne. The results indicate that the proposed second-order coupling model demonstrates superior calibration efficacy compared to the traditional model. Compared with the uncalibrated, the standard deviation of drift phase residuals shows an average decrease of 87.8%, and the root mean square error of fitting decreases by 53.7%. The improvement in both short-term accuracy and long-term stability of mooring gravity measurement is substantial. The ocean navigation gravimetry shows better repeatability and external consistency. Compared with the uncalibrated, the internal and external coincidence accuracy improved by 93.6% and 92.0%, respectively.

Atom gravimeter (AG) is a kind of high-precision absolute gravimeter based on atom interference, which can measure absolute gravitational acceleration. Vibration is one of the important factors which limits the measurement accuracy. Vibration compensation is an effective method to reduce the impact of vibration on measurement accuracy and it is especially suitable for complex vibration environments. In this paper, an improved vibration compensation method is proposed. Based on the simplified model of vibration transfer function, the method searches for the optimal parameters through an improved chaotic sparrow search algorithm (CSSA) to effectively restore the real vibration of the Raman mirror and achieve the best compensation effect. The experimental results show that the improved method proposed in this paper can achieve better compensation effectiveness in less calculation time than the previous methods. The modified atom interference fringe fitting uncertainty can attenuate by 70.21%, and the search time is reduced by nearly 6 times, effectively improves the accuracy and stability of the AG measurement. This method can correct the interference fringes in time when the environment changes, which provides a new idea for the design of vibration compensation method considering dynamic gravimetry with AG.

Atomic gravimeter has been more frequently applied under complex and dynamic environments, but its measurement accuracy is seriously hampered by vibration-induced noise. In this case, vibration compensation provides a way to enhance the accuracy of gravity measurements by correcting the phase noise that resulted from the vibration of a Raman reflector, and improving the fitting of an interference fringe. An accurate estimation of the transfer function of vibration between the Raman reflector and the sensor plays a significant role in optimizing the effect of vibration compensation. For this reason, a vibration compensation approach was explored based on EO (equilibrium optimizer) for estimating the transfer function simplified model of a Raman reflector, and it was used to correct the interference fringe of an atomic gravimeter. The test results revealed that this approach greatly restored the actual vibration of the Raman reflector in a complex vibration environment. With a vibration compensation algorithm, it achieved the correction and fitting of the original interference fringe. In general, it dramatically reduced the RMSE (root mean square error) at the time of fitting and significantly improved the residual error in the gravity measurement. Compared with other conventional algorithms, such as GA (genetic algorithm) and PSO (particle swarm optimization), this approach realized a faster convergence and better optimization, so as to ensure more accurate gravity measurements. The study of this vibration compensation approach could provide a reference for the application of an atomic gravimeter in a wider and more complex environment.