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毕业论文-超低频垂直隔振系统在绝对重力测量中的应用，共89页，37860字
中文摘要
重力加速度（g，常用值 9.81 m/s2）是一项随时间与地点而变化的物理量。影
响重力加速度的因素包括：地球的自转、地球表面的椭球不规则程度、地球内部
物质的密度分布、海洋及固体潮汐等。绝对重力测量在大地测量、地球物理、精
密计量、石油与矿藏勘探、军用导航等诸多领域都有十分重要的应用。
在高精度的绝对重力测量中，通常采用激光干涉测量的方法来跟踪自由落体
物体的运动轨迹，该方法需要一个理想的惯性测量参考点，典型做法是将激光干
涉仪的参考棱镜悬挂在一个垂直隔振平台上，即可减小地面振动噪声对测量参考
点的影响。为了获得较好的隔振效果，隔振系统应该具有很低的本征振荡频率，
亦即比较大的固有周期。
本文主要研究一种基于零长弹簧的超低频垂直隔振系统。利用特殊的零长弹
簧属性及几何悬挂方法，通过精密机械设计和微小角度光电探测技术，以及模拟
**电路反馈控制系统，可以实现固有周期长达 20 秒左右的超低频垂直隔振系统，
并且自动补偿温度变化与弹簧蠕变导致的系统漂移效应。将该系统用于实际的绝
对重力测量（普通实验室地面），单次重力测量结果的标准偏差约为 300 微伽（1
微伽=10-9g），具有显著的隔振效果，基本满足高精度绝对重力测量的需要。
关键词：垂直隔振；零长弹簧；绝对重力测量
ABSTRACT
g - the acceleration of gravity is a physical quantity changing with time and place.
Factors that affect the acceleration of gravity include the Earth’s spin, departures of its
surface from an equipotential spheroid and density variations that occur within the
Earth, ocean and solid tide and so on. Absolute gravity measurement has very
important applications in many fields, such as geodesy, geophysics, metrology, oil and
mineral exploration, assisted navigation, etc.
In order to achieve high-precision absolute gravity measurements, a laser
interferometer is usually used to track the motion of a freely falling body. Therefore, an
ideal inertial measurement reference point is required. The typical method is to
suspend the reference corner cube of the interferometer on a vertical vibration isolation
platform, then the ground vibration noise is isolated from the measurement reference
point. In order to obtain reasonable vibration isolation, the system should have a
natural oscillation with very low frequency, which means a long natural oscillation
period.
This paper studies an ultra-low frequency vertical vibration isolation system based
on a zero-length spring technology. With the use of special zero-length spring
properties and geometric suspension methods, this vertical vibration isolation system
can achieve a natural oscillation period around 20 s, in which precision mechanics
technology, small angle photoelectric detection, and analog circuit feedback control are
applied. In addition, the system drift due to temperature changes and spring drift can
be automatically compensated.
This vibration isolation system has been used in practical absolute gravity
measurement on common laboratory floor. The standard deviation for a single
measurement is about 300 μGal , which means a significant effect of vibration
isolation of the floor noise. This vibration isolation system has very important
potentials to be applied in future high-precision absolute gravity measurement.
Keywords: vertical vibration isolation; zero-length spring; absolute gravity
measurement

目录
*第 1 章 背景与意义 ........1
*1.1 重力测量的意义 .........1
*1.2 重力测量的发展 .........2
*1.3 超低频垂直隔振系统的意义 .........7
*第 2 章 超低频垂直隔振系统 VI-2 .....10
*2.1 系统工作原理 .10
*2.1.1 长周期地震仪 ..10
*2.1.2 VI-2 隔振系统..11
*2.2 系统机械结构 .12
*2.2.1 系统总体结构 ..12
*2.2.2 柔性铰链 13
*2.2.3 摆杆限位 13
*2.2.4 零长弹簧 14
*2.2.5 弹簧悬点调节杠杆 ....16
*2.3 光电探测模块 .17
*2.3.1 位移探测模块的光路设计 ..17
*2.3.2 位移探测模块的电路设计 ..19
*2.3.3 位移探测模块的标定 20
*2.4 电路控制模块 .21
*2.4.1 电路控制的作用及原理 ......21
*2.4.2 电路控制模块的电路设计 ..22
*2.4.3 反馈线圈 29
*2.5 系统的调试 .....29
*2.5.1 典型周期的振荡系统及反馈调节 29
*2.5.2 超长周期振荡系统及其特性 ........33
*第 3 章 重力测量结果及分析 .........36
*3.1 绝对重力仪 MPG2 的组成.36
*3.2 无隔振系统的重力测量结果 .......37
*3.3 应用超级弹簧的重力测量结果 ...38
*3.4 应用 VI-2 隔振系统的重力测量结果....40
*第 4 章 结论与展望 .......43
参考文献 .......45
插图索引 .......47
表格索引 .......50
致谢.......51
声明.......52
附录 A 外文资料书面翻译 ...53