Research Of Algorithms On Gravity Matching Aided Inertial Navigation System

As a country which has so many islands and a large area of ocean,China puts more emphasis on the development of ocean technology because the role of ocean development strategy is more and more important.As an indispensable step of developing ocean technology,the development of underwater vehicles has a strategic significance.Inertial navigation system(INS)is the most widely used navigation system for underwater navigation and positioning of submarines and has the characteristics of autonomy and concealment.However,INS calculates the position of the underwater vehicle through integral operation,and the navigation error It will gradually accumulate as the navigation time of the underwater vehicle increases.For underwater vehicles that need to perform long-endurance missions,this accumulated drift error is a fatal flaw.Therefore,other passive navigation methods need to be used to correct the accumulated drift error of inertial navigation.The gravity field is the information field that exists on the earth itself.The gravity matching assisted inertial navigation system can perfectly fit with underwater navigation.It can satisfy the requirements of concealment,high precision and passivity of underwater vehicles,in the meantime,it can correct the drift of INS.This paper aims at the difficulty of long-endurance underwater autonomous navigation for submarine vehicles,and considering that the traditional gravity line matching algorithm technology has the problem of low accuracy of matching results,the research on underwater intelligent navigation technology is carried out,and a new concept of "gravity lighthouse navigation" is proposed.The new idea solves the problem that the underwater long-term navigation accuracy does not satisfy the combat requirements.Construct a theoretical system of "gravity lighthouse navigation",breaking through key technologies such as the scientific expression of gravity lighthouses,measuring and making of gravity lighthouses,and matching navigation of gravity lighthouses,and verifying the completeness and technical feasibility of gravity lighthouse navigation theory by simulation.Provide a new solution to effectively solve the problem of underwater long-endurance navigation.This paper takes the gravity matching inertial navigation system as the object,and conducts in-depth research on the construction of gravity database in key sea areas and the surface matching algorithm of "gravity lighthouse navigation".The main work and innovations done in the paper are summarized as follows:(1)Briefly describe the basic principles and error models of the inertial navigation system;summarize the basic principles of gravity matching assisted navigation and introduce the composition of the system;compare and analyze the current three main ocean gravity field models,and summarize based on satellite measurements.High data to establish the theory of ocean gravity anomaly reference map;simulate the traditional gravity line matching algorithm and summarize its characteristics and defects.(2)A new concept of "gravity lighthouse navigation" was proposed,and key technologies such as the scientific expression of gravity lighthouse,measurement and system of gravity lighthouse,and surface matching navigation of gravity lighthouse in the algorithm of "gravity lighthouse navigation" were simulated and verified;Solve the shortcomings of the low matching success rate of traditional gravity line matching algorithms with new and intelligent ideas,and solve the problem of long-endurance underwater navigation accuracy that does not satisfy combat requirements.