超导重力梯度仪交叉耦合效应的实验研究

项目名称： 超导重力梯度仪交叉耦合效应的实验研究

项目编号： No.41474060

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 刘向东

作者单位： 华中科技大学

项目金额： 80万元

中文摘要： 超导重力梯度仪具有固有噪声低稳定性高的优点，在航空资源勘探等领域有广阔的应用前景，其研制是国际前沿研究课题。超导重力仪器的固有噪声只代表其分辨率的物理极限，在动态应用环境下，外部耦合噪声远高于固有噪声。因此，压制外部噪声是超导重力梯度仪实用化的核心任务。在外部噪声中，非敏感自由度的交叉耦合噪声是一个关键项。本项目通过实验手段，分别独立测量超导加速度计中相对运动与磁场串扰两种基本交叉耦合关系，并在实验测试基础上，最终完成超导加速度计结构与电磁参数设计优化。在此基础上，利用全自由度超导磁悬浮检验质量，开展超导重力梯度仪中敏感方向重力测量与非敏感自由度控制的交叉耦合效应研究，系统评估超导重力梯度仪中的交叉耦合效应，提出抑制动态环境下超导重力梯度仪交叉耦合噪声的有效技术方案。本项目的顺利实施将为超导重力仪器的工程化与实用化提供必不可少的基础实验数据，从基础层面支撑我国超导重力仪器的研制。

中文关键词： 超导重力梯度仪；航空重力测量；超导加速度计；交叉耦合效应

英文摘要： With the intrinsically low noise and high stability, superconducting gravity instrument (SGI) is considered as the most promise instruments in precision gravity measurements, and thus expected to become a more powerful air-borne tool in exploration survey. However，the low SGI intrinsic noise indicates nothing else but the physical limit to the sensitivity. In the practical dynamic environment, the extrinsic noise, which is resulted from the coupling of environmental noise into measurements, will be much larger than the intrinsic one. Thus, depression of extrinsic noise is essentially important for applicable SGI. Among them, the cross-coupling noise (CCN) from vibration in non-sensitive degrees of freedom is a key item. In this project, we will precisely and independently measure the cross-coupling functions for two basic cross-coupling mechanics in superconducting accelerometer, i.e., the coupling through the relative motion of the test mass with respect to the reference frame and that through magnetic interference. Based on the measurement results, we will be able to carry out the design of superconducting accelerometer with optimized CCN and test it experimentally. Furthermore, concerning the superconducting gravity gradiometer, we will investigate the cross-couplings between signal detection in sensitive degree of freedom and feedback controlling in non-sensitive degrees of freedom, and search for effective method to depress the CCN. The project aims at providing fundamental experimental data which is indispensable for the design of applicable superconducting gravity instruments.

英文关键词： superconducting gravity gradiometer;airborne gravity measurement;superconducting accelerometer;cross-talking effect