Research And Realization Of Laser Strapdown Inertial Navigation System Algorithm Under Highly Dynamic Enviromment

Because of the unique advantage of being free from any outside interference,inertial navigation has become the most important guidance way of many carriers,such as missiles, aircrafts and ships. Strapdown inertial navigation system(SINS),taking laser gyroscopes as sensing devices, has developed fastly in recentyears, therefore precision problem has become the bottleneck of its furtherdevelopment, which is also the main reason why it can not take place of platformINS. There are several ways to improve the precision of SINS, among which hignprecision navigation algorithm is a good method. This paper is just designed tostudy and solve such a problem.The main research work of this paper includes the following three parts:(1) the detailed error analysis of strapdown inertial navigation system isconducted. After talking about the basic working principle of SINS, the papermainly studied its error sources, including inertial components errors, navigationalgorithms errors, coning error and so on, and their influence of navigationprecison.(2) Takign typical coning motion and typical sculling motion for inspectionenvironment, the paper made in-depth study of the attitude algorithm, speedalgorithm and location algorithm of SINS under highly dynamic environment.The equivalent rotation vector algorithm and its optimal form under typicalconing motion are discussed. Then, under other dynamic environments，the paperanalysized the adaptability of coning optimal algorithm. After that, the scullingeffect error in velocity resolution and the scrolling effect error in positionresolution are studied, the paper conducted related compensation algorithms andtheir optimized form.(3) Choosing PC/104as the navigation processor, A laser gyro strapdowninertial navigation system (LSINS) entity is designed. A PC control software,which is used for serial interface communication, is developed in VC++6.0environment. The work also includes calibration of IMU and initial alignment of LSINS. After that, relying on the3-axis precision turntable in our laboratory,several practical navigation experiments are delivered. Through the analysis ofexperimental results, we get some practical conclusions in engineering.The theory research and experiment results show that, if other conditionskeep unchanged, high precision navigation algorithm are able to effectivelyinhibit and compensate the error resources of SINS, and its navigation precitioncan be significantly improved.