光纤陀螺磁热耦合效应研究

New output phenomenon appears,when fiber optic gyroscope(FOG) is in the magnetic field and temperature varying at the same time. The drift is not the accumulating of the drift from magnetic field and the one from the temperature varying. The amplitude of the magnetic- temperature drift is much more than the sum that the magnetic field drift and the temperature field drift add together. The new mechanism that the magnetic field and the temperature field interact each other to FOG exists. So the research on the mechanism that the magnetic field and the temperature interact each other is very important to manufacturing FOG and improving the environment suitability of FOG..To establish the mathematics model that the two physical field, magnetic and temperature, affect FOG, to analyze the temperature, magnetic and magnetic- temperature performance of the fiber loop which is the sensitive core of FOG, to show the relationship between the magnetic-temperature coupling effect with magnetic field, temperature field and the fiber loop's parameters of FOG, and to calculate the magnitude of the magnetic-temperature coupling noise from putting the emulating result into the theory model are the main contents. To design the magnetic-temperature experiment circumstance tests and verifies the emulating result, making use of interference depolarizing FOG which has been existed. From the research, the result that the magnetic field sensitivity of FOG can be restrained less than 0.01 /h/mT ,in the circumstance that the temperature range is 10℃～60℃ and the temperature varying is 1℃/min.

光纤陀螺在磁、热两种物理场同时作用下，产生新的输出现象。其漂移并非单纯磁场和单纯热场下分别产生漂移的简单叠加，漂移的幅度比两单独物理场分别产生漂移的代数和大数倍，存在陀螺受磁-热两种物理场相互耦合作用的新机制。搞清磁-热耦合效应产生的机理，对于研制光纤陀螺、提高光纤陀螺的环境适应性具有指导意义。.建立光纤陀螺磁-热两种物理场产生耦合效应的数学模型，使用有限元方法对陀螺核心敏感环进行磁、热及磁-热耦合性能仿真分析，揭示磁-热耦合漂移与磁场、温度、光纤陀螺敏感环各参数之间的关系，将仿真结果带入理论模型计算磁-热耦合漂移的大小。设计磁-热实验环境，利用已有的干涉式消偏光纤陀螺系统，对仿真结果进行实验验证。试图在温度范围为10℃～60℃、温升为1℃/分钟的热环境下，将消偏光纤陀螺的磁场灵敏度抑制到小于0.01 /h/mT。

光纤陀螺在磁、热两种物理场同时作用下，产生严重的漂移，漂移幅度比两单独物理场分别产生漂移的代数和大数倍，存在磁-热两种物理场的相互耦合，严重影响了光纤陀螺的使用精度、制约了光纤陀螺的使用领域，搞清磁-热耦合效应产生的机理，对于光纤陀螺的工程化、提高光纤陀螺的环境适应性具有重要的指导意义。.本项目研究了光纤陀螺在磁-热两种物理场同时作用下产生交联耦合效应的机理，建立了相应的数学模型，并进行了实验验证。具体包括如下几项内容：有限元仿真了磁场在光纤环上的分布；有限元仿真了温度场及引起的双折射在光纤环上的分布；将磁场引起的圆双折射和温度引起的应力双折射代入光纤陀螺干涉场光路模型，计算产生的非互易相位差；还首次发现了与光的传播方向正交的磁场对光产生影响的新机理；基于该机理，研究了单模光纤环、单消偏光纤陀螺、双消偏光纤陀螺、保偏光纤陀螺在与光的传播方向正交的磁场作用下产生的非互易相位差的大小与各参数之间的关系；首次提出了使用软件补偿方法补偿轴向磁场对光纤陀螺产生的非互易相位差；首次提出采用特种光纤进行光纤陀螺轴向磁场灵敏度的补偿；分别搭建了消偏光纤陀螺系统和保偏光纤陀螺系统，对以上理论进行了验证，实验结果证明了上述理论的正确性。.上述机理的提出和数学模型的建立，为光纤陀螺的研制、光纤陀螺的实际应用及工程化，提供了理论指导，为新型全光纤高灵敏度磁场的测量提供了一种新的测量方法。