Research On Calibration Method And Combined Positioning Technology Of SINS/USBL Integrated System

In order to achieve the goal of a powerful marine economy,the underwater engineering equipment(AUV)is indispensable as an important equipment which can be used to detect marine resources and seabed topography.However,the key technologies to ensure the efficient patrol,high precision,high reliability and high concealment of AUV are basically monopolized by foreign countries.Therefore,China must speed up its development and implement them as soon as possible.AUV is now fully localized.Strapdown inertial navigation system(SINS)has the advantages of high autonomy,high concealment and comprehensive output of position and attitude data,but its positioning error will increase with time.Ultra Short Base Line(USBL)system has the advantages of high positioning accuracy and no error accumulation effect,but it has incomplete data output and low output frequency.Aiming at the problem that the navigation coordinate system of SINS/USBL integrated navigation system is not uniform with that of USBL,this paper designs a calibration technology for the installation error of SINS/USBL integrated navigation system,which makes the positioning accuracy after calibration 64.3% higher than that before calibration.Aiming at the disadvantage of single SINS or USBL,this paper designs two SINS/USBL integrated navigation forms to achieve high-precision navigation of AUV.The main contents of this paper are as follows:Firstly,the development status of AUV equipment at home and abroad and the research status of installation error calibration were investigated in detail.The Bellhop underwater acoustic toolkit was used to simulate the underwater channel of a lake,and the underwater real environment was successfully simulated.A repetitive generalized cross-correlation time delay estimation algorithm is proposed.The delay error of the new algorithm is 0.0112 s,which can be improved by 46.4% compared with the old algorithm by 0.0209 s.The USBL location technology based on delay gap distance location is improved.Secondly,for the calibration part of underwater transponder,a spherical intersection model solution method based on Adomian decomposition is proposed.For the installation error calibration part,a calibration algorithm based on Singular Value Decomposition(SVD)decomposition is proposed.The installation error angle of SINS/USBL can be calculated by the new installation error calibration algorithm,and the calibration accuracy can reach 0.05 degree.Thirdly,aiming at the requirement of underwater practical application object and the situation of using environment,a loosely integrated SINS/USBL integrated navigation mode is designed.On this basis,in view of the complex environment of the seabed,in order to improve the stability of the system,a combined navigation mode is designed,which can reduce the precision and maintain the continuous working ability of the system when a hydrophone is missing.Finally,the navigation modes of these two systems are simulated.The ocean simulation results show that SINS/USBL can achieve 2.2‰D positioning accuracy,and the three-hydrophone integrated navigation mode can achieve 3.1‰ positioning accuracy.Fourthly,on the Yangtze River Basin of the first section of the Nanjing Yangtze River Bridge,the actual test of the prototype has been completed.The calibration technology is used to process the actual measurement data.The positioning accuracy of 03472 m after calibration and the maximum positioning error of SINS/USBL integrated navigation are 3.5621 m,which verifies the correctness of the integrated installation error calibration and SINS/USBL integrated navigation algorithm.