CN-121978628-A - Seabed datum point positioning method based on systematic error influence mechanism

CN121978628ACN 121978628 ACN121978628 ACN 121978628ACN-121978628-A

Abstract

The invention discloses a submarine reference point positioning method based on a systematic error influence mechanism, which belongs to the underwater positioning technology and is used for submarine reference point positioning, and comprises the steps of constructing an observation equation for submarine reference point acoustic positioning, obtaining an observation value residual vector by adopting least square adjustment, and extracting a residual vector direction systematic error; the method comprises the steps of establishing a regression relation between a residual vector direction system error and angles of corresponding opposite sides based on a local weighted regression method, calculating a solution vector direction system error by adopting the regression relation, substituting the obtained system error into an observation equation, and carrying out system error compensation and high-precision seabed datum point positioning. The invention obtains the system error through the influence mechanism of the system error on the least square parameter solution, obviously improves the positioning precision of the seabed datum point, and can provide technical support for the construction and maintenance of the seabed datum network, the monitoring of ocean disasters, the ocean positioning service and the like.

Inventors

WANG ZHENJIE
ZHANG SHIMEI
ZHAO SHUANG

Assignees

中国石油大学(华东)

Dates

Publication Date: 20260505
Application Date: 20260407

Claims (10)

1. A method for locating a subsea reference point based on a systematic error affecting mechanism, comprising: S1, determining a reference point, obtaining the bidirectional propagation time of an acoustic signal from a sea surface acoustic transducer to the reference point, constructing an observation equation from the sea surface acoustic transducer to the reference point by utilizing sound velocity profile data, and obtaining the observation equation of all observation epochs after linearization by utilizing Taylor series expansion; S2, solving a coordinate correction of the reference point by using a least square method, calculating an observation value residual vector based on the coordinate correction, and extracting a residual vector direction system error by using a wavelet transformation method; S3, restraining the systematic errors and the coordinates of the seabed datum points by using the continuity and priori coordinates of the adjacent epoch systematic errors, calculating to obtain a systematic error estimated value by adopting a weight selection fitting method, calculating a solution vector direction systematic error by combining the residual vector direction systematic error, calculating an angle of opposite sides of the residual vector according to the solution vector direction systematic error and the residual vector direction systematic error, and establishing a regression relation between the residual vector direction systematic error and the angles of the corresponding opposite sides by adopting a local weighted regression method; S4, calculating residual vector direction systematic errors of all the seabed datum points except the reference datum points based on a local weighted regression equation to predict corresponding angle vectors, and calculating systematic errors of solution vector directions; S5, calculating a systematic error vector of the seabed datum point by using the systematic error of the residual vector direction and the systematic error of the vector direction of the seabed datum point, correcting an observation equation, calculating a coordinate correction of the seabed datum point by using the corrected observation equation, and calculating a corrected seabed datum point position by combining the initial coordinates of the seabed datum point.
2. The method for locating a seabed datum point based on a systematic error influence mechanism according to claim 1, wherein the method is characterized in that the method comprises the following steps that S1.1, one seabed datum point is selected as a reference datum point in seabed datum points with the same observation condition, an acoustic signal is transmitted to the seabed by using a sea surface acoustic transducer, a response acoustic signal of the reference datum point is received, two-way propagation time of the acoustic signal is obtained, and an observation equation from the sea surface acoustic transducer to the reference datum point is constructed by using sound velocity profile data: ; In the formula, , For the number of total observation epochs, Is the first The acoustic distance between the individual observation epoch sea-surface acoustic transducer and the reference datum, , For the sound velocity value, Is the first The bi-directional propagation time of the individual observation epoch acoustic signals, For the theoretical distance of the sea surface transducer from the reference datum, Is the first The coordinates of the sea-surface acoustic transducer for each observation epoch, As the coordinates of the reference point of reference, Is a random error; Is the first Systematic error of individual observation epochs: ; In the formula, Is the first The systematic errors of the individual observation epochs caused by the delay of the subsea transponder, Is the first The relative systematic error of the sound velocity of each observation epoch, Is the first Dividing each observation epoch And External systematic errors.
3. The method for locating a seabed datum point based on a systematic error influence mechanism as claimed in claim 2, wherein the step S1 comprises the steps of S1.2, performing Taylor series expansion on an observation equation of a propagation distance from a sea surface acoustic transducer to a reference datum point to obtain an observation equation of all observation epochs after linearization: ; In the formula, For the difference between the observed value of acoustic ranging and the theoretical distance, Is a design matrix of the coordinate parameters, Coordinate correction for the reference point that is not solved; To observe errors: ; In the formula, To transpose the symbols.
4. The method for locating a seabed datum point based on a systematic error affecting mechanism as recited in claim 3, wherein S2 comprises S2.1 solving based on least square method adjustment : ; In the formula, As the correction of the coordinates of the reference point, The weight matrix is an observation value weight matrix; S2 comprises, S2.2, based on Calculating an observation residual vector : ; S2 comprises S2.3, extracting by adopting a wavelet transformation method Is the systematic error of (2) 。
5. The method for locating a seabed reference point based on a systematic error influence mechanism as claimed in claim 4, wherein S3 comprises S3.1, constraining the systematic error and the seabed reference point based on the continuity and priori coordinates of the systematic error of adjacent epochs, and obtaining a systematic error estimated value by adopting a weight selection fitting method Will be And Difference is made to obtain a solution vector direction system error : ; ; ; In the formula, In order to estimate the vector of values, In order to design the matrix, , Is a matrix of units which is a matrix of units, In order to regularize the matrix, In order for the parameters to be regularized, To take advantage of the continuance of systematic errors in adjacent epochs The obtained system error weight matrix is used for obtaining the system error weight matrix, , , Is a weight array of the coordinate components, = ; S3 comprises, S3.2, according to And Calculation of At an angle to the opposite side : 。
6. The method for locating a reference point on a sea floor based on a systematic error affecting mechanism according to claim 5, wherein S3 comprises S3.3, establishing by a local weighted regression method And The regression relationship of (1) includes, constructing a dataset , Is the first From observation epochs , Is that Corresponding angles, for each of Constructing a regression model at the target point The local weighted regression model at: ; In the formula, The vector of the variables that are the arguments, 1 Is the intercept term, 1 is the term, Is the order of the polynomial, Is that A kind of electronic device To the power of the two, As the coefficient of regression of the coefficient of the data, Is a noise term.
7. The method for locating a reference point on a sea floor based on a systematic error affecting mechanism according to claim 6, wherein S3 comprises S3.4 solving an estimated value of a regression coefficient by a weighted least square method : ; ; In the formula, As a vector of the dependent variables, , In order to be a diagonal weight matrix, In order to design the matrix, Is that A kind of electronic device To the power.
8. The method for locating a seafloor reference point based on a systematic error affecting mechanism according to claim 7, wherein S4 comprises, for the seafloor reference points other than the reference points, calculating a residual vector direction systematic error for each of the seafloor reference points based on a locally weighted regression equation And predicts the corresponding angle vector And calculates the systematic error of the direction of the solution vector : 。
9. The method for locating a reference point on a sea floor based on a systematic error affecting mechanism as recited in claim 8, wherein S5 includes S5.1, based on And Calculating a systematic error vector : ; By using Observation vector for a subsea reference point other than a reference point And (3) correcting: ; In the formula, Is an observation vector corrected for a seabed reference point other than the reference point.
10. The method for locating a reference point on a sea floor based on a systematic error affecting mechanism according to claim 9, wherein S5 comprises S5.2, calculating a corrected coordinate correction vector : ; In the formula, For a design matrix of subsea fiducial points other than the reference fiducial point, An observation weight matrix for the seabed datum points except the reference datum point; s5 comprises S5.3, calculating corrected seabed datum point positions except the datum point : ; In the formula, Is the initial coordinates of the seabed datum other than the reference datum.

Description

Seabed datum point positioning method based on systematic error influence mechanism Technical Field The invention discloses a submarine reference point positioning method based on a systematic error influence mechanism, and belongs to the underwater positioning technology. Background Due to the influence of the complex marine environment, the accurate positioning of the seabed datum point faces a plurality of technical problems. Among these, systematic errors are the most important factors affecting the accuracy of positioning of the seabed fiducial. Systematic errors in acoustic positioning of the seafloor fiducial point mainly include errors such as acoustic velocity measurement errors, representative errors, hardware delay errors, GNSS positioning errors, equipment installation bias, transducer travel differences, and the like. The fine processing of the systematic errors is a difficult problem to be solved in the high-precision positioning of the seabed datum points. At present, the systematic error processing method in the positioning of the seabed datum point mainly comprises a differential method and a model compensation method. In order to weaken the systematic error between observed values, a method for positioning the seabed datum point by utilizing a differential technology is provided, the observed values of adjacent epochs are subjected to difference in the single transponder, the long-period term systematic error can be eliminated, and if different transponders exist, the positioning is performed by a double-difference method, and the short-period term systematic error can be further eliminated. The underwater non-difference positioning method based on the double-pass sound path is provided by considering the position difference of the transducer at the receiving and transmitting time. The subsequent double-pass difference method is provided on the basis of the double-pass sound paths. Although the differential algorithm can eliminate the influence of systematic errors and improve the positioning precision of the seabed datum point, the differential algorithm has the problems of reduced equation number, easy pathological observation equation and the like. In terms of model compensation research of system error processing, most researches are carried out based on sound velocity. In order to solve the influence of the time variation of the sound velocity structure, a polynomial or B-spline function is adopted to fit a sound velocity error in a sliding time window, and the coordinates of the seabed datum point and the sound velocity correction parameters are solved at the same time. Further a GNSS-acoustic positioning model taking the sound velocity horizontal gradient into consideration is provided subsequently to eliminate the influence of the sound velocity error on the horizontal positioning accuracy. And establishing an elastic observation model with time deviation and distance deviation parameters and an elastic observation model with periodic error parameters, and effectively compensating the influence of system errors. And a state space equation is constructed, and Kalman filtering is adopted to perform sequential estimation on the sound velocity error, so that the sound velocity error estimation level is improved. The model compensation method for processing the systematic errors weakens the influence of the systematic errors to a certain extent, but still has the problems that part of the systematic errors are not estimated, the precision of the parameter solution is still to be improved, and the like. Thus, while model and algorithm studies of systematic error handling in subsea reference point positioning have made great progress, subsea reference point positioning observations exhibit complex varying characteristics due to the influence of complex marine environments. Systematic errors are both systematic and random, and it is difficult to find systematic reasons completely from the environment to exclude. Under the condition that the influence mechanism of the system error on the least square solution is not clear in the least square adjustment, the influence mechanism of the system error on the least square solution is deeply analyzed, and a new method for processing the submarine reference point positioning system error is developed, so that the method is a key for improving the submarine reference point positioning accuracy. Disclosure of Invention The invention aims to provide a seabed datum point positioning method based on a systematic error influence mechanism, which aims to solve the problems that in the prior art, the seabed datum point positioning observation presents complex change characteristics due to the influence of a complex ocean environment, systematic errors are systematic and random, and systematic reasons are difficult to completely find from the environment to eliminate. A seabed datum point positioning method based on a systematic error influence mechanism co