气压变化对光纤陀螺仪零偏稳定性的影响及抑制方法研究

Research on Restrain Method of Effect on FOG Zero Bias from Variety of Atmospheric Pressure

光纤陀螺仪可用于测量载体相对惯性空间的角运动,是光纤惯导系统的核心部件。因此,要求光纤陀螺仪具有较高的精度和良好的环境适应性。光纤环是光纤陀螺仪的角速度敏感部件,光纤环受到环境因素影响,将导致光纤陀螺仪精度下降,因此需要对光纤环采取适当的保护措施。分析了气压变化导致光纤陀螺仪零偏稳定性变差的机理:环境气压的急剧变化,会使光纤环上产生附加应力,造成光纤的折射率分布不均,导致光路产生非互易性相位差,使光纤陀螺仪零偏产生漂移,零偏稳定性变差;并提出了对光纤陀螺仪进行密封的措施来抑制该效应。经试验验证,采用此密封设计后,光纤陀螺仪在变气压环境中的零偏稳定性改善了近10倍。

Fiber optic gyroscope(FOG) can be used for measuring the vehicle of carrier relative to the inertial space,and is the core component of fiber inertial navigation system.Therefore,a high precision and good environmental adaptability of fiber optic gyroscope is required.Fiber-optic ring is the angular speed sensitive component of FOG,fiberoptic ring influenced by environmental factors,will lead to decline in the accuracy of the FOG.Therefore,taking some steps to protect the fiber-optic ring is needed.The paper analyzes the atmospheric pressure change lead to partial stability mechanism of variation of FOG zero:dramatic changes in the pressure of environment,can cause additional stress on fiber-optic ring,caused by the refractive index distribution of the fiber,led the fiber road to the reciprocal of phase difference,make produce FOG zero bias drift,zero bias stability variation;and put forward the sealing measures to restrain the effect.After verification by experiment,this paper adopts the design of seal after the FOG in the variable air pressure environment of the zero bias stability is improved almost ten times.