Design And Dynamic Research Of Vibration Isolation System For Strapdown IMU Based On Dither RLG

The Dynamic Analysis of the structure of The Inertial Measuring Unit(IMU) with the Mechanically Dithered Ring Laser Gyroscope(MDRLG) was studied in this paper to solve the problem when the miniaturizing design,the shock absorption design and the losing weight design was implemented.Firstly, the idea about vibration isolation and the MDRLG dither was presented, and the requirement of the shock absorption structure layout of the IMU was given. Also, the requirement of the shock absorption system and the prime structure form was given out.Secondly, the dynamic analysis methods (include Modal Analysis,Harmonic Response Analysis and Transient Dynamic Analysis) and its meaning,theory and approach was given. After suitable simplification applied to the assembly model of IMU system,the finite element model was built using the finite element analysis(FEA) software ANSYS .The method of dampers-modeling of the IMU system was described. The dynamic response analysis was applied based on the FE model built previously.Basing the study of FEA Modal Analysis, a three-degree-freedom model of SINS with one mechanical dither gyroscope is presented. By these analysis the rationality of IMU's structure design was proved, and the problem of RLG's shake was solved.Lastly,By comparing the simulation results with the corresponding experiment results,it was indicated that the biggest error between them was less. The method of finite element modeling introduced was proven to be correct and feasible.