CN118244377B - A gravimeter calibration method traced back to the law of universal gravitation - Google Patents

Abstract

The present application belongs to the field of gravity measurement technology, and specifically discloses a gravimeter calibration method that can be traced back to the law of universal gravitation. The method uses two G measurement methods, namely the periodic method and the angular acceleration method, on a set of G measurement devices to measure the G source of the gravitational source used by the gravitational field device. The gravitational field device uses different attractive mass configurations to generate a gravitational field that is uniform in the horizontal direction and axisymmetric in the vertical direction. The gravitational acceleration change and its uncertainty are both within the set range, which can effectively improve the reliability of the gravimeter calibration and achieve high-precision calibration of the gravimeter. The present application is different from the traditional gravimeter calibration method. Through high-precision G measurement and tracing, the reliability and accuracy of various parameters of the gravitational source in the gravitational field device can be verified, and a gravimeter calibration method and technology that is decoupled from electromagnetic force and can be traced back to the law of universal gravitation is provided. The accuracy and scope of application can be greatly improved by replacing the configuration method.

Description

A gravimeter calibration method traced back to the law of universal gravitation

Technical Field

The present application belongs to the field of gravity measurement technology, and more specifically, to a gravimeter calibration method traceable to the law of universal gravitation.

Background technique

High-precision gravimeters are widely used in basic scientific research, resource exploration, the establishment of an international gravity standardization network, and the monitoring of vertical crustal movement. After long-term use, the internal sensitive components of the gravimeter are affected, causing the instrument's measurement results to deviate greatly from local gravity changes, and the gravimeter's instrument accuracy needs to be calibrated regularly. The calibration of gravity instruments generally uses gravitational effects. For example, the tidal effects of the moon and the sun can be used to test the scale factor of the gravimeter, and combined with observational data, the measurement resolution of the absolute gravimeter can be obtained. However, the tide itself has uncertainty, and its accuracy depends on the accuracy of the tidal model and cannot be controlled artificially.

Therefore, how to improve the reliability of gravimeter calibration is an urgent problem to be solved.

Summary of the invention

In view of the defects of the prior art, the purpose of the present application is to provide a gravimeter calibration method traceable to the law of universal gravitation, which can effectively improve the reliability of gravimeter calibration and achieve high-precision calibration of gravimeter.

To achieve the above purpose, the present application provides a gravimeter calibration method traceable to the law of universal gravitation, comprising the following steps:

S10, in the same set of G measuring device, two G measuring methods, namely the period method and the angular acceleration method, are used to measure the G source of the gravitational source used in the gravitational field device, and various geometric and physical parameters of the gravitational source are adjusted according to the uncertainty of the G measuring results of the two methods;

S20, in the same gravitational field device, using different attracting mass configurations to generate a gravitational field that is uniform in the horizontal direction and axisymmetric in the vertical direction, and calculating the acceleration change and its uncertainty generated by the total gravitational source; wherein the attracting mass is composed of multiple gravitational sources placed on a support in the gravitational field device;

S30, determining whether the acceleration change and its uncertainty in step S20 are within the set range, if yes, proceeding to step S40, if not, adjusting the attracting mass configuration and proceeding to step S20;

S40, moving the attracted mass in the gravitational field device to cause it to produce an acceleration change, using a gravimeter to measure the change, and calculating the acceleration change value produced by the attracted mass, and comparing it with the measurement value obtained by the gravimeter, and finally calibrating the gravimeter according to the comparison result.

The gravimeter calibration method traceable to the law of universal gravitation provided in the present application is different from the traditional gravimeter calibration method. Through high-precision G measurement and tracing, the reliability and accuracy of various parameters of the gravitational source in the gravitational field device can be verified, and a gravimeter calibration method that is decoupled from the electromagnetic force and traceable to the law of universal gravitation is provided. By replacing the attracting mass configuration method, its accuracy and reliability can be greatly improved, and the measurement performance of the gravimeter can be effectively improved.

As a further preferred embodiment, before step S20, the method further includes:

In the same gravitational field device, the influence of the background gravitational field is differentially subtracted through different configurations with and without a gravitational source.

As further preferred, the gravitational source is a regular sphere, and the geometric and physical parameters of the gravitational source include sphere mass, sphere diameter, sphere roundness, sphere eccentricity and sphere magnetism.

As a further preferred embodiment, step S10 is specifically as follows:

S11, dividing the gravitational sources used in the gravitational field device into multiple groups, each group of gravitational sources includes 4 gravitational sources; wherein the 4 gravitational sources are placed in two layers on the support in the G- measuring device, and are fixed on the attracting mass turntable by a three-point support method, and the attracting mass turntable is driven to rotate by a stepping motor driven by a controller;

S12, measuring the geometric and physical parameters of each group of gravitational sources;

S13, in the same set of G measurement equipment, use the period method and the angular acceleration method to measure the G of each group of gravitational sources, and synthesize and evaluate the error of the G values measured by the two methods for each group of gravitational sources to obtain the G measurement results and their uncertainties of the two methods;

S14, determine whether the uncertainty of the G measurement results of the two methods meets the threshold requirements. If so, proceed to step S20. If not, adjust the geometric and physical parameters of the gravity source and then proceed to step S12.

As a further preferred method, the periodic method for measuring G is to change the magnitude of the gravitational force between the attracting mass and the torsion balance in the G measuring device by switching the relative position between them, and measure the periodic change caused thereby to give the G value;

The angular acceleration method for measuring G is to use the inertial moment generated by the rotating suspension turntable of the torsion balance to balance the gravitational moment of the attracting mass on the torsion balance, so that the torsion balance remains stationary relative to the suspension turntable, and the G value is obtained by measuring the angular acceleration of the suspension turntable.

Among them, when using the periodic method to measure G , the attraction mass turntable is controlled to achieve the switching between the near and far configurations of the attraction mass; when using the angular acceleration method to measure G , the collected angle signal of the attraction mass turntable is used as the control input of the attraction mass turntable, and the controller determines the speed difference between the suspension point turntable and the attraction mass turntable and then adjusts the frequency to drive the stepper motor to rotate the attraction mass turntable, and then determines the rotation speed of the suspension point turntable through the angle signal of the suspension point turntable and makes the attraction mass turntable follow the suspension point turntable to rotate, so as to keep the speed difference between the two turntables constant.

As a further preferred embodiment, in step S13, the G value measured by the periodic method of the i- th group of gravitational sources is and its uncertainty The calculation formula is:

G value measured by the angular acceleration method for the i- th group of gravitational sources and its uncertainty The calculation formula is:

Wherein, Δ C _g represents the gravitational coupling term determined by the length, distance and mass parameters of the torsion balance and the attracting mass in the G- measuring device; Δ ω ² represents the square difference under the near-remote configuration; Δ K represents the difference in elastic coefficient of the torsion wire suspending the torsion balance under the near-remote configuration; I represents the moment of inertia of the torsion balance; α _t ( ω ) represents the angular acceleration amplitude at the frequency of the torsion balance motion signal; P _g represents the parameters related to the mass, size and relative position of the torsion balance and the gravitational source; represents the correction term of magnetic damping effect; represents the correction term for air buoyancy effect; Indicates The error of geometric and physical parameters in contributing to the G value measured by the periodic method; Indicates The error contributed by the geometric and physical parameters to the G value measured by the angular acceleration method.

As a further preferred method, in step S13, the G measurement result of the periodic method is used. and its uncertainty The calculation formula is:

G measurement results using the angular acceleration method and its uncertainty The calculation formula is:

In the formula, , They represent the relative weights of the G values measured by the periodic method and the angular acceleration method for the i- th group of gravitational sources respectively.

As a further preference, in step S14, the threshold value of the uncertainty of the G measurement result is required to be less than 1×10 ^-4 .

As further preferred, in step S20, the attracting mass configuration includes single-layer, multi-layer, single-loop and multi-loop.

As a further preferred embodiment, in step S30, the acceleration variation caused by the total gravitational source is set in a range of tens of microgallons, and the uncertainty of the acceleration variation caused by the total gravitational source is set in a range of less than 0.05 microgallons.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a flow chart of a gravimeter calibration method traceable to the law of universal gravitation provided in an embodiment of the present application;

FIG. 2 is a schematic diagram of a traceability chain provided in an embodiment of the present application.

Detailed ways

In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

It should be understood that, in the description of the present application, the term "several" means at least one, such as one, two, etc., unless otherwise clearly and specifically defined; the term "plurality" means two or more, unless otherwise clearly and specifically defined; the terms "first" and "second" etc. are used to distinguish different objects rather than to describe a specific order of objects; the term "and/or" includes any and all combinations of one or more related listed items.

In addition, references throughout this specification to "one embodiment," "one embodiment," "an example," or similar language indicate that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present application. Thus, appearances of the phrase "in one embodiment," "in one embodiment," and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

In order to solve the problem of unreliable calibration of traditional gravimeter calibration methods, the present application provides a gravimeter calibration method traceable to the law of universal gravitation, using a G measuring device and a gravitational field device, and the measurement principle is: first trace the gravitational source in the gravitational field device used for calibration to the law of universal gravitation through the G measuring device, and then use the gravitational field generated by the gravitational source in the gravitational field device to calibrate the gravimeter. The calibration method provided by the present application can provide a standard gravitational field traceable to the law of universal gravitation for the gravimeter, improve the reliability of gravimeter calibration, and achieve high-precision calibration of the gravimeter.

It should be noted that the G- measuring device provided in the present application adopts the G- measuring device structure known in the art, that is, it includes a vacuum container, a torsion balance suspended in the vacuum container by a torsion wire, a suspension point turntable for rotating the torsion balance, a support member and other auxiliary equipment. The gravitational field device provided in this embodiment adopts the gravitational field device structure known in the art, that is, it includes multiple gravitational sources, a support member, a moving member and other auxiliary equipment. Multiple gravitational sources are placed on the support member to form an attracting mass. The attracting masses of different configurations generate a gravitational field that is uniform in the horizontal direction and axisymmetric in the vertical direction. By moving the attracting mass up and down, the moving member can generate acceleration changes to calibrate the gravimeter.

As shown in FIG. 1 and FIG. 2 , the gravimeter calibration method traceable to the law of universal gravitation provided in the present application includes steps S10 to S40, which are described in detail as follows:

S10, in the same set of G measurement equipment, two G measurement methods, namely the periodic method and the angular acceleration method, are used to measure the G source of the gravitational source used in the gravitational field device, and the various geometric and physical parameters of the gravitational source are adjusted according to the uncertainty of the G measurement results of the two methods.

Step S10 provided in this embodiment may specifically be:

(1) To measure the geometric and physical parameters of each gravitational source used in the gravitational field device;

(2) Using the same set of G measurement equipment, two G measurement methods, the period method and the angular acceleration method, are used to measure the G of the gravitational source and trace it back to its source. The G measurement results and their uncertainties of the two methods are obtained.

(3) Determine whether the uncertainty of the G measurement results of the two methods meets the threshold requirements. If so, proceed to step S20. If not, adjust the geometric and physical parameters of the gravitational source and then proceed to step (1).

In step (1), the gravitational source used in the gravitational field device can be a regular sphere, and its geometric and physical parameters need to be measured before step S20, including the mass, diameter, roundness, eccentricity and magnetism of the sphere. Specifically, the gravitational source provided in this embodiment can be a 28 stainless steel ball with a weight of about 8.5 kg and a diameter of about 127 mm, and a 12 tungsten ball with a weight of about 20.78 kg and a diameter of about 127 mm.

Furthermore, step (1) may also include the following steps: performing error allocation for each experiment, calculating the error contributed by each parameter of the gravitational source to the experimental result, and finally selecting the tool used to measure the parameter. Specifically, the tool used in this embodiment may include: a mass comparator, with a minimum relative standard uncertainty of ^10-7 for mass measurement; a roundness meter, with a minimum roundness measurement accuracy of ^10-6 m; and a length ratio meter, with a relative standard uncertainty of ^10-7 for length measurement.

Preferably, step S10 provided in this embodiment may adopt steps S11 to S14, which are described in detail as follows:

S11, dividing the gravitational sources used in the gravitational field device into multiple groups, each group of gravitational sources includes 4 gravitational sources.

S12, measure the geometric and physical parameters of each group of gravitational sources.

S13, in the same set of G measurement equipment, use the periodic method and angular acceleration method to measure the G of each group of gravitational sources and obtain the G value and its uncertainty of each group of gravitational sources using the periodic method and angular acceleration method. Then, synthesize and error evaluate the G values of each group of gravitational sources measured by the two methods to obtain the G measurement results and their uncertainties of the two methods.

In step S13, the basic idea of the periodic method for measuring G is to change the magnitude of the gravitational force between the attracting mass and the torsion balance in the G measuring device by switching the relative position between them, and to measure the periodic change caused thereby to give the G value. Therefore, the G value measured by the periodic method for the i- th group of gravitational sources is The calculation formula is:

In the formula, Δ C _g represents the gravitational coupling term determined by the torsion balance in the G- measuring device and the length, distance, mass and other parameters of the attracted mass; Δω ² represents the square difference under the near-remote configuration; Δ K represents the difference in elastic coefficients of the torsion wire that suspends the torsion balance under the near-remote configuration; I represents the moment of inertia of the torsion balance.

The basic idea of the angular acceleration method for measuring G is to use the inertial torque generated by the rotating torsion balance's suspension turntable to balance the gravitational torque of the attracting mass on the torsion balance, so that the torsion balance remains stationary relative to the suspension turntable, and the G value is obtained by measuring the angular acceleration of the suspension turntable. Therefore, for the i -th group of gravitational sources, the G value measured using the angular acceleration method is The calculation formula is:

Wherein, α _t ( ω ) represents the angular acceleration amplitude at the frequency of the torsion balance motion signal; P _g represents the parameters related to the mass, size and relative position of the torsion balance and the gravitational source; represents the correction term of magnetic damping effect; Represents the correction term for air buoyancy effect.

In this embodiment, when a G- measuring device is used to measure and trace the G of each group of gravitational sources, the attracting mass adopts four spherical gravitational sources, and the four spherical gravitational sources are placed in two layers in the upper and lower layers on the support in the G- measuring device. The four spherical gravitational sources are fixed on the attracting mass turntable in a three-point support manner, and the attracting mass turntable is driven to rotate by a stepper motor driven by a controller.

In the periodic method G measurement experiment, the switching of the attracting mass between the near and far configurations can be achieved by controlling the attracting mass turntable.

In the angular acceleration method for measuring G , the collected rotation angle signal of the attraction mass turntable is used as the control input of the attraction mass turntable. The controller determines the speed difference between the suspension point turntable and the attraction mass turntable and then adjusts the frequency to drive the stepper motor to rotate the attraction mass turntable. Then, the rotation speed of the suspension point turntable is determined by the rotation angle signal of the suspension point turntable and the attraction mass turntable is made to rotate with the suspension point turntable to keep the speed difference between the two turntables constant. In this embodiment, the frequency of the experimental signal to be measured is twice the speed difference between the two turntables.

In this embodiment, when the uncertainty of the G tracing results of a group of gravitational sources is evaluated, it is necessary not only to use the various parameters measured by the gravitational source in step S12, but also to accurately measure the relevant parameters, including the distance between the sphere centers, the relative position between the geometric center of the scale bar and the center of the sphere, etc. In addition, it is necessary to analyze the system effects in the tracing process, including one or more of the magnetic damping effect, air buoyancy effect, background gravitational gradient effect, electromagnetic field effect, torsion wire thermoelastic effect, torsion wire anelastic effect and gravitational nonlinear effect.

Assuming that the uncertainty components contributed by each parameter are independent and uncorrelated, according to the uncertainty synthesis formula, the uncertainty of the G value measured by the periodic method for the i-th group of gravitational sources is finally obtained: for:

The uncertainty of the G value measured by the angular acceleration method for this group of gravitational sources is for:

In the formula, Indicates The error contributed by the geometric and physical parameters to the G value measured by the periodic method can be obtained through the error transfer formula of the function; Indicates The error contributed by the geometric and physical parameters to the G value measured by the angular acceleration method can be obtained through the error transfer formula of the function.

The G value measured by the periodic method is synthesized and the error is evaluated, and the calculation formula is:

The G value measured by the angular acceleration method is synthesized and the error is evaluated. The calculation formula is:

In the formula, , They represent the relative weights of the G values of the i- th group of gravitational sources measured by the periodic method and the angular acceleration method. Finally, the G measurement result G _ToS and its uncertainty u _ToS of the periodic method, and the G measurement result G _AAF and its uncertainty u _AAF of the angular acceleration are obtained.

S14, judging whether the uncertainty of the G measurement results of the two methods both meet the threshold requirement, which can be set to be less than 1×10 ^-4 . If so, proceed to step S20 . If not, adjust the geometric and physical parameters of the gravitational source and then proceed to step S12 .

In the above steps, this embodiment uses the period method and the angular acceleration method to perform G measurement experiments on the same set of G measurement equipment. The two methods are completely independent and mutually verified, which can effectively improve the reliability and accuracy of G measurement traceability.

Preferably, before performing the subsequent step S20, in the same set of gravitational field device, the influence of the background gravitational field of the support in the gravitational field device can be differentially deducted through different configurations with and without a gravitational source.

Step S20, using different attracting mass configurations to generate a gravitational field that is uniform in the horizontal direction and axisymmetric in the vertical direction, and calculating the acceleration change and its uncertainty generated by the total gravitational source.

In step S20, different attracting mass configurations of the gravitational field device include four configurations: single-layer, multi-layer, single-circle and multi-circle, specifically: a single-layer ring configuration of 12 tungsten balls; an upper and lower ring configuration of 16 stainless steel balls; a single-layer ring configuration of 9 tungsten balls; a single-layer ring configuration, an inner circle of 12 tungsten balls, an outer circle of 12 stainless steel balls, which are used to generate a horizontally uniform and vertically axisymmetric gravitational field to calibrate the gravimeter.

In step S20, the acceleration change calculation formula generated by the kth gravitational source is:

In _the formula, Vk _and ρk represent the volume and density of the kth gravitational source respectively; ( X0 _, Y0 , Z0 ₎ represent _the coordinates of the test mass in the gravimeter; ( Xk _, Yk _, Zk ) represent the coordinates of the center point _of the kth gravitational source; G represents the gravitational constant.

The calculation formula _for the uncertainty of acceleration change uA generated by the total gravitational source is:

In the formula, is the acceleration uncertainty provided by the kth gravitational source, and its calculation formula is:

In the formula, δV _k , δρ _k , ( δX ₀ , δY ₀ , δZ ₀ ), ( δX _k , δY _k , δZ _k ) and δG represent the measurement errors corresponding to parameters V _k , ρ _k , ( X ₀ , Y ₀ , Z ₀ ), ( X _k , Y _k , Z _k ) and G , respectively.

Step S30, determining whether the acceleration change and its uncertainty in step S20 are both within the set range, if so, proceeding to step S40, if not, adjusting the suction mass configuration and proceeding to step S20.

In step S30, the acceleration variation range generated by the total gravitational source is set to be tens of microgallons, and the uncertainty range of the acceleration variation generated by the total gravitational source is set to be less than 0.05 microgallons.

This embodiment uses different attracting mass configurations on the same set of gravitational field devices to generate a gravitational field that is uniform in the horizontal direction and axisymmetric in the vertical direction. The gravitational acceleration variation reaches tens of microgals, and the accuracy is better than 0.05 microgals. It can provide a standard gravitational field traceable to the law of universal gravitation for gravimeter calibration, effectively improving the reliability and accuracy of the calibration.

Step S40, moving the attracting mass in the gravitational field device to cause it to produce an acceleration change, using a gravimeter to measure the change, then calculating the acceleration change value produced by the attracting mass, and comparing it with the measurement value obtained by the gravimeter, and finally calibrating the gravimeter according to the comparison result.

Preferably, in this embodiment, the calculated acceleration change generated by the gravitational field device and the measurement value obtained by the gravimeter can be used to fit the gravimeter calibration coefficient using the least squares method to obtain the calibration coefficient and complete the gravimeter calibration.

The gravimeter calibration method traceable to the law of universal gravitation provided in this embodiment is different from the traditional gravimeter calibration method. Through high-precision G measurement and tracing, the reliability and accuracy of various parameters of the gravitational source in the gravitational field device can be verified, and a gravimeter calibration method that is decoupled from the electromagnetic force and traceable to the law of universal gravitation is provided. By changing the attracting mass configuration method, its accuracy and reliability can be greatly improved, and the measurement performance of the gravimeter is effectively improved.

It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims (10)

1. The gravity meter calibration method tracing to the law of universal gravitation is characterized by comprising the following steps:

S10, in the same set of G measuring device, G measuring and tracing are carried out on the gravitation source used in the gravitational field device by using two G measuring methods of a periodic method and an angular acceleration method, and each geometrical and physical parameter of the gravitation source is adjusted according to uncertainty of G measuring results of the two methods;

s20, in the same gravitational field device, gravitational fields with uniform horizontal direction and axisymmetric vertical direction are generated by adopting different attraction mass configurations, and the acceleration change and uncertainty of the total gravitational source are calculated; wherein the attraction mass is formed by placing a plurality of attraction sources on a support in the attraction field device;

s30, judging whether the acceleration change and the uncertainty thereof in the step S20 are within the set range, if so, performing the step S40, and if not, performing the step S20 after adjusting the suction quality configuration;

And S40, moving the attraction mass in the gravitational field device to generate acceleration change, measuring the change by using a gravity meter, calculating an acceleration change value generated by the attraction mass, comparing the acceleration change value with a measured value obtained by the gravity meter, and finally calibrating the gravity meter according to a comparison result.

2. The gravity calibration method according to claim 1, further comprising, before step S20:

In the same gravitational field device, the influence of the background gravitational field is subtracted differentially through different configurations of the gravitational source and the gravitational source.

3. The gravity calibration method according to claim 1, wherein the gravitational source is a regular sphere, and the geometric and physical parameters of the gravitational source include sphere mass, sphere diameter, sphere roundness, sphere eccentricity and sphere magnetism.

4. The gravity calibration method according to claim 1, wherein step S10 specifically comprises:

S11, dividing gravitational force sources used in the gravitational field device into a plurality of groups, wherein each group of gravitational force sources comprises 4 gravitational force sources; the four-gravity source is divided into an upper layer and a lower layer, and is placed on a support piece in the G measuring device, and is fixed on an attraction quality rotary table in a three-point support mode, and the attraction quality rotary table is driven by a stepping motor to rotate through a controller;

S12, measuring geometric and physical parameters of each group of gravitation sources;

S13, in the same set of G measuring device, G measuring and tracing are carried out on each group of gravitation sources by using two methods of a periodic method and an angular acceleration method, and G values measured by using two methods of each group of gravitation sources are synthesized and evaluated in error to obtain G measuring results and uncertainty of the G measuring results of the two methods;

S14, judging whether the uncertainty of the G measurement results of the two methods meets the threshold requirement, if so, performing step S20, and if not, performing step S12 after adjusting the geometric and physical parameters of the gravitation source.

5. The gravity meter calibrating method according to claim 4, wherein the periodic method G is to change the gravitational force between the attraction mass and the torsion balance in the G measuring device by switching the relative positions between them, and to measure the periodic variation caused thereby to give the G value;

the angular acceleration method G is to balance the attractive force moment of the attractive mass acting on the torsion balance by utilizing the inertia moment generated by the torsion balance by the suspension turntable rotating the torsion balance, so that the torsion balance is kept static relative to the suspension turntable, and the G value is obtained by measuring the angular acceleration of the suspension turntable;

when G is measured by using a periodic method, the attraction quality is switched between near and remote configuration by controlling the attraction quality turntable; when the angular acceleration method is used for measuring G, the collected rotation angle signal of the attraction mass turntable is used as the control input quantity of the attraction mass turntable, the controller judges the rotation speed difference between the suspension point turntable and the attraction mass turntable so as to adjust the frequency driving stepping motor to enable the attraction mass turntable to rotate, then the rotation speed of the suspension point turntable is judged through the rotation angle signal of the suspension point turntable, the attraction mass turntable rotates along with the suspension point turntable, and the rotation speed difference of the two turntables is kept constant.

6. The gravity calibration method according to claim 4, wherein in step S13, the G value measured by the periodic method is used by the ith group of gravitational sourcesAnd its uncertaintyThe calculation formula of (2) is as follows:

G value measured by angular acceleration method for ith group of gravity sources And its uncertaintyThe calculation formula of (2) is as follows:

Wherein Δc _g represents an attractive force coupling term determined by a torsion balance in the G-measuring apparatus and the length, distance, and mass parameters of the attractive mass; Δω ² represents the squared error in the near-remote configuration; Δk represents the difference in the spring rate of the torsion wire suspending the torsion balance in the near-remote configuration; i represents the moment of inertia of the torsion balance; alpha _t (omega) represents the angular acceleration amplitude at the torsion balance motion signal frequency; p _g represents parameters related to the mass, size and relative position of the torsion balance and the gravitational source; representing a magnetic damping effect correction term; Representing an air buoyancy effect correction term; Represent the first Errors of contribution of term geometry and physical parameters to the G value measured by a periodic method; Represent the first The term geometry and physical parameters measure the error contributed by the G value to the angular acceleration method.

7. The method for calibrating a gravity meter according to claim 6, wherein in step S13, G is measured according to a periodic methodAnd its uncertaintyThe calculation formula of (2) is as follows:

g measurement result by angular acceleration method And its uncertaintyThe calculation formula of (2) is as follows:

In the method, in the process of the invention, 、The relative weights of G values measured by the periodic method and the angular acceleration method are respectively represented by the i-th group of gravitational sources.

8. The gravity calibration method according to claim 4, wherein in step S14, the threshold requirement for uncertainty of the measurement G is less than 1×10 ^-4.

9. The method of calibrating a gravitational meter tracing to the law of universal gravitation as recited in claim 1, wherein in step S20, said attractive mass configuration comprises a single layer, multiple layers, a single turn, and multiple turns.

10. The method for calibrating a gravitational meter according to claim 1, wherein in step S30, the set range of acceleration variation generated by the total gravitational source is tens of micro-gamma, and the set range of uncertainty of acceleration variation generated by the total gravitational source is less than 0.05 micro-gamma.