CN112415634B - Dynamic gravimeter zero drift compensation method based on satellite gravity anomaly information - Google Patents

Dynamic gravimeter zero drift compensation method based on satellite gravity anomaly information Download PDF

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CN112415634B
CN112415634B CN202011161400.2A CN202011161400A CN112415634B CN 112415634 B CN112415634 B CN 112415634B CN 202011161400 A CN202011161400 A CN 202011161400A CN 112415634 B CN112415634 B CN 112415634B
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gravity
satellite
information
dynamic
gravimeter
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CN112415634A (en
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陆凯
杨源
梁杰
单瑞
李攀峰
孙建伟
杜润林
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Qingdao Institute of Marine Geology
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Abstract

The invention discloses a dynamic relative gravimeter zero drift compensation method based on satellite gravity anomaly information, which comprises the following steps: (1) measuring operation is carried out based on the dynamic relative gravimeter according to operation rules and data are processed to obtain gravity anomaly information on a measuring line
Figure DDA0002744432550000011
(2) Analyzing to obtain the average value of the dynamic gravity anomaly output by the gravimeter on a single measuring line
Figure DDA0002744432550000012
(3) Obtaining gravity anomaly information output by satellite gravity at different positions of survey line by interpolation method using satellite gravity information
Figure DDA0002744432550000013
And averaging the values
Figure DDA0002744432550000014
(4) Gravity anomaly information output by satellite gravity
Figure DDA0002744432550000015
Calibrating gravity anomaly information output by the near-surface relative gravimeter to obtain
Figure DDA0002744432550000016
Aiming at the problem that the zero position of the dynamic relative gravity sensor has nonlinear drift, the zero position of the dynamic relative gravity meter is calibrated by using the satellite gravity abnormal information on the survey line, so that the system difference is reduced, and the dynamic gravity measurement precision is effectively improved.

Description

Dynamic gravimeter zero drift compensation method based on satellite gravity anomaly information
Technical Field
The invention relates to the field of dynamic relative gravimeter compensation, in particular to a zero drift compensation method for a dynamic relative gravimeter based on satellite gravity anomaly information.
Background
The gravity anomaly is an important component of geophysical field information, is a core element of the gravity field environment information, and has important significance in the fields of resource exploration, geophysical research, battlefield environment construction, underwater autonomous navigation, weapon precision striking and the like. The gravity field measurement has various means, but in contrast, the main way to obtain high-precision, high-spatial resolution and large-range gravity field information is still near-surface dynamic relative gravity measurement.
In the prior art, the dynamic relative gravimeter, the free space gravity anomaly δ g can be obtained by deformation of the inertial navigation ratio equation:
Figure BDA0002744432530000011
in the formula (I), the compound is shown in the specification,
Figure BDA0002744432530000016
representing the original gravity in units of 10-5m/s2(ii) a Gamma denotes normal gravity in units of 10-5m/s2；
Figure BDA0002744432530000012
Indicating the vertical acceleration of the carrier, and also being expressed as
Figure BDA0002744432530000013
Unit 10-5m/s2；
Figure BDA0002744432530000014
Indicating an Hertefss correction, calculated from external navigation information, unit 10-5m/s2. In the data processing process, vertical acceleration correction, Hertefis correction and normal gravity field correction are carried out by means of GNSS satellite navigation information; in addition, it is generally considered that the vertical acceleration can be eliminated by low-pass filtering in the shipborne gravity measurement
Figure BDA0002744432530000015
The influence of (c).
In the measuring process, the zero drift of the gravity sensor can cause the overall deviation of the measured data to form a system difference. In order to inhibit the zero drift of the gravity sensor, the traditional method is to improve the stability of the output signal of the sensor, the temperature control precision, the shock absorption efficiency of the shock absorber and other measures, but the method can make the system more complicated and reduce the reliability, increase the volume and the cost of the system, and the inhibition effect cannot completely meet the application requirement.
Considering that the current dynamic relative gravimeter is limited by the technology level and the electronic circuit technology, the zero drift problem can not be solved in principle, and the zero drift can only be inhibited by measures of improving the temperature control precision, the shock absorption efficiency of the shock absorber and the like as far as possible. Therefore, a new method is urgently needed to be designed, so that the zero drift relative to the gravity meter is restrained, and the system difference is reduced, so that the aim of improving the dynamic gravity measurement precision is fulfilled.
Disclosure of Invention
The invention provides a zero drift compensation method of a dynamic relative gravity meter based on satellite gravity abnormal information, which aims at the problem that the zero of a dynamic relative gravity sensor has nonlinear drift and utilizes the satellite gravity abnormal information on a survey line to calibrate the zero of the dynamic relative gravity meter, and can effectively reduce system difference and improve the dynamic gravity measurement precision.
The invention is realized by adopting the following technical scheme: a dynamic relative gravimeter zero drift compensation method based on satellite gravity anomaly information comprises the following steps:
step A, according to the operationThe rule carries out measurement operation based on the dynamic relative gravimeter and processes data to obtain gravity anomaly information delta g on a measuring lineiI ═ 1,2,3, … …, N denotes the number of measurement points;
b, analyzing to obtain the average value delta g of the dynamic gravity anomaly output by the relative gravimeter on a single measuring line0；
Step C, obtaining gravity anomaly information output by the gravity of the satellite at different positions of the survey line by utilizing the gravity information of the satellite through an interpolation method
Figure BDA0002744432530000021
And averaging the values
Figure BDA0002744432530000022
Step D, gravity anomaly information output by satellite gravity
Figure BDA0002744432530000023
And (3) calibrating the gravity anomaly information output by the near-surface relative gravimeter to obtain:
Figure BDA0002744432530000024
Figure BDA0002744432530000025
the relative gravity measured value is corrected by the satellite gravity.
Further, the step a is specifically realized by the following steps:
step A1, carrying dynamic relative gravimeter by using the mobile platform to carry out conventional measurement operation, and obtaining carrier position information vectors P of each time point in the measurement processiI-1, 2,3, … …, N, and synchronized gravity sensor output information
Figure BDA0002744432530000026
Wherein the position information vector is:
Figure BDA0002744432530000027
in the formula:
Figure BDA0002744432530000028
the latitude of the ith measurement point; lambda [ alpha ]iLongitude of the ith measurement point; h isiIs the height of the ith measurement point;
step A2, outputting information to gravity sensor
Figure BDA0002744432530000029
Performing vertical acceleration correction, normal gravity field correction and Hertefsh correction to obtain gravity anomaly information delta g corresponding to each measurement point position on the measurement linei。
Further, in the step C, when interpolating the satellite gravity by using the position information of each measurement point on the survey line, the following method is specifically adopted:
(1) obtaining satellite gravity information through public data to obtain a position point to be interpolated
Figure BDA00027444325300000210
Defining vectors formed by longitude and latitude of the four position points and satellite gravity abnormal values in the interior of the four position points with known satellite gravity values as
Figure BDA00027444325300000211
And
Figure BDA00027444325300000212
namely, the method comprises the following steps:
Figure BDA00027444325300000213
wherein the content of the first and second substances,
Figure BDA00027444325300000214
the latitude of the ith measurement point; lambda [ alpha ]iLongitude of the ith measurement point; h isiIs the height of the ith measurement point;
Figure BDA00027444325300000215
and
Figure BDA00027444325300000216
denotes latitude, λaAnd λbWhich represents the longitude of the vehicle,
Figure BDA00027444325300000217
and
Figure BDA00027444325300000218
satellite gravity outliers of the four location points respectively;
(2) defining intermediate variables α and β:
Figure BDA0002744432530000031
this results in a linear interpolation formula:
Figure BDA0002744432530000032
in the formula
Figure BDA0002744432530000033
And
Figure BDA0002744432530000034
is an intermediate variable;
(3) further obtaining:
Figure BDA0002744432530000035
the gravity values of the satellite at each position point on the measuring line are obtained and averaged
Figure BDA0002744432530000036
The calculation formula is as follows:
Figure BDA0002744432530000037
compared with the prior art, the invention has the advantages and positive effects that:
the method develops a new method, creatively provides a method for calibrating the dynamic relative gravimeter by utilizing the satellite gravity anomaly information with extremely small zero drift but low spatial resolution and high precision, obtains the gravity anomaly information on the measuring line, outputs the average value of the gravity anomaly by the dynamic relative gravimeter on a single measuring line and combines the average value of the gravity anomaly information output by the satellite gravity on the measuring line, combines the advantage of high resolution of the relative dynamic gravimeter and the advantage of high stability of the satellite gravity to obtain a relative gravity measurement value after the satellite gravity correction, realizes the reduction of the zero drift error of the gravity sensor in the scheme, and improves the measurement precision.
Drawings
FIG. 1 is a schematic flow chart illustrating a zero drift compensation method according to an embodiment of the present invention;
fig. 2 is a schematic diagram of interpolation of satellite gravity information according to an embodiment of the present invention.
Detailed Description
In order to make the above objects, features and advantages of the present invention more clearly understood, the present invention will be further described with reference to the accompanying drawings and examples. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those described herein, and thus, the present invention is not limited to the specific embodiments disclosed below.
A dynamic relative gravimeter zero drift compensation method based on satellite gravity anomaly information, as shown in FIG. 1, includes the following steps:
(1) according to the operation rule, measurement operation is carried out based on the dynamic relative gravimeter, data are processed, and gravity anomaly information on a measuring line is obtained, specifically:
the conventional measurement operation is carried out by utilizing mobile platforms such as airplanes, ships and warships and the like to carry dynamic relative gravimeters, and the measurement process is recorded through GNSSVector P of position information of carrier at each point in timei(i ═ 1,2,3, … …, N) and synchronized gravity sensor output information
Figure BDA0002744432530000041
Wherein the position information vector is:
Figure BDA0002744432530000042
in the formula:
Figure BDA0002744432530000043
-latitude of the ith measurement point;
λi-longitude of the ith measurement point;
hi-height of the ith measurement point.
The data processing is carried out on the output information of the gravity sensor, and the data processing method specifically comprises the following steps: utilizing GNSS navigation information to mainly be vertical acceleration correction, normal gravity field correction and Hertefsh correction, wherein:
the vertical acceleration correction formula is as follows:
Figure BDA0002744432530000044
the normal gravitational field correction formula is:
Figure BDA0002744432530000045
in the formula ge＝9.78049m/s2Representing the gravitational acceleration on the equatorial sea level.
The ertfsh correction formula is:
Figure BDA0002744432530000046
in the formula:
Ω -east velocity of the vector;
ve-rotational angular velocity of the earth;
v-horizontal velocity of the vector;
r-the radius of the earth.
After the three correction items, the gravity anomaly information delta g corresponding to each measuring point position on the measuring line can be obtainedi(i＝1,2,3,……,N)。
(2) Calculating the average value delta g of the dynamic gravity anomaly output by the relative gravimeter on a single measuring line0；
Figure BDA0002744432530000047
In the formula, δ g0The average value of the dynamic relative gravity anomaly on the measuring line is shown to be relative to the output gravity anomaly of the gravimeter.
(3) Obtaining gravity anomaly information of the gravity output of the survey line satellite by utilizing satellite gravity information through an interpolation method
Figure BDA0002744432530000048
And averaging the values
Figure BDA0002744432530000049
Specifically, the satellite gravity is interpolated by using the position information of each point on the survey line to obtain the satellite gravity abnormal information of each position point
Figure BDA0002744432530000051
In view of the fact that the latitude information in the currently disclosed satellite gravity information is in an equally-spaced form, the embodiment adopts a bilinear interpolation method on the premise of ignoring elevation influence, which specifically comprises the following steps:
as shown in FIG. 2, by reading the public satellite gravity information, the position point to be interpolated can be always found
Figure BDA0002744432530000052
Gravity in four known satellitesInside the position points of the value, defining the longitude and latitude of the four position points and the vector formed by the satellite gravity abnormal value as
Figure BDA0002744432530000053
And
Figure BDA0002744432530000054
namely, the method comprises the following steps:
Figure BDA0002744432530000055
wherein the content of the first and second substances,
Figure BDA0002744432530000056
the latitude of the ith measurement point; lambda [ alpha ]iLongitude of the ith measurement point; h isiIs the height of the ith measurement point;
Figure BDA0002744432530000057
and
Figure BDA0002744432530000058
denotes latitude, λaAnd λbWhich represents the longitude of the vehicle,
Figure BDA0002744432530000059
and
Figure BDA00027444325300000510
satellite gravity outliers of the four location points respectively;
defining intermediate variables alpha and beta, and calculating the formula as follows:
Figure BDA00027444325300000511
the linear interpolation formula is thus obtained as:
Figure BDA00027444325300000512
in the formula
Figure BDA00027444325300000513
And
Figure BDA00027444325300000514
is an intermediate variable;
further obtaining:
Figure BDA00027444325300000515
the gravity values of the satellite at each position point on the measuring line are obtained and averaged
Figure BDA00027444325300000516
Figure BDA00027444325300000517
(4) The gravity anomaly information output by the satellite gravity is utilized to calibrate the gravity anomaly information output by the near-surface relative gravimeter, and the advantage of high resolution of the relative dynamic gravimeter and the advantage of high stability of the satellite gravity are fused to obtain:
Figure BDA00027444325300000518
in the formula
Figure BDA00027444325300000519
Is a relative gravity measurement value after satellite gravity correction.
The current dynamic relative gravimeter is limited by the technology level and the electronic circuit technology, the zero drift problem can not be solved in principle, and the zero drift can only be inhibited by measures of improving the temperature control precision, the shock absorption efficiency of the shock absorber and the like as far as possible. The invention develops a new method, calibrates the dynamic relative gravimeter by using the satellite gravity abnormal information with extremely low zero drift, low spatial resolution and high precision, reduces the zero drift error of the gravity sensor in the scheme, improves the measurement precision, and has better practical application and reference value.
The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention in other forms, and any person skilled in the art may apply the above modifications or changes to the equivalent embodiments with equivalent changes, without departing from the technical spirit of the present invention, and any simple modification, equivalent change and change made to the above embodiments according to the technical spirit of the present invention still belong to the protection scope of the technical spirit of the present invention.

Claims (2)

1. The dynamic relative gravimeter zero drift compensation method based on satellite gravity anomaly information is characterized by comprising the following steps of:
step A, measuring operation is carried out based on a dynamic relative gravimeter according to operation rules and data are processed to obtain gravity anomaly information delta g on a measuring lineiI ═ 1,2,3, … …, N denotes the number of measurement points;
b, analyzing to obtain the average value delta g of the dynamic gravity anomaly output by the relative gravimeter on a single measuring line0；
Step C, obtaining gravity anomaly information output by the gravity of the satellite at different positions of the survey line by utilizing the gravity information of the satellite through an interpolation method
Figure FDA0003132235770000011
And averaging the values
Figure FDA0003132235770000012
(1) Obtaining satellite gravity information through public data to obtain a position point to be interpolated
Figure FDA0003132235770000013
Defining the longitude and latitude of four position points and the satellite in the interior of the four position points with known gravity values of the satelliteThe vectors formed by the gravity abnormal values are respectively
Figure FDA0003132235770000014
And
Figure FDA0003132235770000015
namely, the method comprises the following steps:
Figure FDA0003132235770000016
wherein the content of the first and second substances,
Figure FDA0003132235770000017
the latitude of the ith measurement point; lambda [ alpha ]iLongitude of the ith measurement point; h isiIs the height of the ith measurement point;
Figure FDA0003132235770000018
and
Figure FDA0003132235770000019
denotes latitude, λaAnd λbWhich represents the longitude of the vehicle,
Figure FDA00031322357700000110
and
Figure FDA00031322357700000111
satellite gravity outliers of the four location points respectively;
(2) defining intermediate variables α and β:
Figure FDA00031322357700000112
this results in a linear interpolation formula:
Figure FDA00031322357700000113
in the formula
Figure FDA00031322357700000114
And
Figure FDA00031322357700000115
is an intermediate variable;
(3) further obtaining:
Figure FDA00031322357700000116
the gravity values of the satellite at each position point on the measuring line are obtained and averaged
Figure FDA00031322357700000117
The calculation formula is as follows:
Figure FDA00031322357700000118
step D, gravity anomaly information output by satellite gravity
Figure FDA00031322357700000119
And (3) calibrating the gravity anomaly information output by the near-surface relative gravimeter to obtain:
Figure FDA00031322357700000120
Figure FDA00031322357700000121
the relative gravity measured value is corrected by the satellite gravity.
2. The method for compensating the zero drift of the relative gravimeter based on the abnormal information of the gravity of the satellite according to claim 1, wherein: the step A is specifically realized by the following steps:
step A1, carrying dynamic relative gravimeter by using the mobile platform to carry out conventional measurement operation, and obtaining carrier position information vectors P of each time point in the measurement processiI-1, 2,3, … …, N, and synchronized gravity sensor output information
Figure FDA0003132235770000021
Wherein the position information vector is:
Figure FDA0003132235770000022
in the formula:
Figure FDA0003132235770000023
the latitude of the ith measurement point; lambda [ alpha ]iLongitude of the ith measurement point; h isiIs the height of the ith measurement point;
step A2, outputting information to gravity sensor
Figure FDA0003132235770000024
Performing vertical acceleration correction, normal gravity field correction and Hertefsh correction to obtain gravity anomaly information delta g corresponding to each measurement point position on the measurement linei。
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