空间用光纤陀螺辐射诱导磁场误差变化机理研究

Study on the variation mechanism of radiation-induced magnetic field error in space fiber optic gyroscope

摘要:

干涉式光纤陀螺在空间环境下受粒子辐射、电磁场等多种物理场共同影响,使角速度输出误差劣化。本文通过分析光纤陀螺磁场误差主要来源,推导了光纤陀螺磁场误差模型。基于磁场误差模型探究辐射对磁场误差相关参数的影响,建立辐射诱导磁场误差变化理论模型。在此基础上,通过影响机理分析和实验验证,确定辐射主要通过影响维尔德常数和光纤应力双折射进而影响光纤陀螺输出零偏。进一步地,通过搭建小型化光纤陀螺样机,对保偏光纤环进行辐射处理并进行了相应磁场误差测试。测试结果表明,光纤陀螺磁场误差随辐射总剂量发生变化,其变化规律符合辐射诱导磁场误差变化模型。

Abstract:

Interferometric fiber optic gyroscope (IFOG) is affected by various physical fields such as space radiation and electromagnetic field in space environment, which will deteriorate the gyro output performance. In this paper, the magnetic field error model of fiber optic gyroscope is derived by analyzing the main sources of the magnetic field error of fiber optic gyroscope. Based on the magnetic field error model, the influence of radiation on the parameters of magnetic field error was investigated and the theoretical model of radiation-induced magnetic field error was established. Based on the model, by the mechanism analysis and experimental verification, it is determined that the radiation mainly affects the output zero bias of IFOG by changing the Verdet constant and stress-induced birefringence. Furthermore, by establishing a miniaturized IFOG prototype, the polarization maintaining fiber coil was radiated and the corresponding magnetic field error was measured. The experimental results show that the magnetic field error of IFOG varies with the total radiation dose, and its variation law conforms to the radiation induced magnetic field error variation model.