Research On FOG's Temperature Characteristic Based On The Finite Element Method

Fiber optic gyro(FOG)is a new kind of angular rate sensor based on Sagnac effect.Compared with traditional gyroscope,it has a lot of advantage such as performance,technology,cost and life and so on and has become the core of the third generation of inertial measurement system components.But the environmental temperature make the FOG produce noise and drift,which greatly limits the application of it.Therefore,we need to do some research work about the temperature characteristic of FOG.In this article,research on FOG's temperature characteristic focuses on optical fiber ring,which is the core component of FOG.The research on FOG's temperature performance was produced through the analyzing the temperature field of optical fiber ring.In first chapter,the purpose and significance of the FOG's temperature characteristic was explained,and the current research status of the subject at home and abroad was introduced.In the second chapter,the basic work principle of FOG and the reciprocity principle was introduced in the first place of the road.Then,the issue that the temperature drift is one of the biggest problems of FOG was determined through analyzing the temperature's effect disturbance on the gyro performance.In the third chapter,the improved three-dimensional model of Shupe error was put forward,on the basis of predecessors' work.The 3-d discretization method was put forward for the concrete winding method.In the forth chapter,the optical fiber ring temperature control equations were derived,through the analysis of the three-dimensional heat transfer process in optical fiber ring.The finite element model to solve fiber optic ring's temperature field was established.In the fifth chapter,the validity of the model was validated,through in the process of alternating high and low temperature test of gyroscope zero output and Shupe error comparison between the calculated value.And error sources of the model were analyzed.In the last chapter,the temperature of the FOG drift was analyzed,through the Shupe error model.First of all the characteristics of the temperature disturbance for optical fiber ring in different directions are analyzed.Then,in view of the optical fiber length must be part of different layers in the design process,the choice of the number of turns on the properties ofoptical fiber ring temperature effect are analyzed in comparison.After the outside in the process of the optical fiber ring around the two layer around and asymmetric ring around the two full round ring not ideal conditions to study the effect of gyro temperature characteristics.Finally combined with optical fiber ring temperature field analysis and structure design problem for structural optimization scheme of fiber optic gyroscope is discussed.