Calibration method for inclination sensor of relative gravimeter

Abstract

The invention discloses a relative gravimeter inclination sensor calibration method. The method comprises the following steps: step 1, preparation before calibration of a relative gravimeter inclination sensor; step 2, acquiring a detection data set of the calibrated inclination sensor; 3, obtaining an actually measured inclined gravity model through curve fitting by using the detection data set; step 4, carrying out reference 0-bit calibration on the calibrated inclination sensor; 5, calibrating the sensitivity of the calibrated inclination sensor relative to the gravimeter; the method comprises the following steps: by collecting gravity and inclination detection data sets, establishing an inclination gravity model of actually measured gravity readings and inclination readings; according to the inclination gravity model, solving the correct reference 0 position and the accurate position of the sensitivity of the calibrated inclination sensor, and according to the solving result, realizing the calibration of the reference 0 position and the sensitivity of the calibrated inclination sensor; according to the method, an accurate adjustment value is directly given, calibration is rapidly completed, the calibration time is saved, and the calibration efficiency of the relative gravimeter calibration inclination sensor is improved.

Description

Technical Field

[0001] The invention relates to the technical field of relative gravimeters, in particular to a relative gravimeter tilt sensor calibration method. Background Art

[0002] Gravity measurement is an important surveying and mapping technology, which is widely used in geophysics, surveying and mapping, geology and aerospace. Gravity measurement is to measure the gravity acceleration of a point on the ground using a gravimeter, and relative gravity measurement is to measure the difference of gravity acceleration between two points on the ground using a relative gravimeter.

[0003] Two mutually orthogonal uniaxial tilt sensors are installed on the relative gravimeter to monitor the tilt state of the relative gravimeter.

[0004] Due to the influence of ambient temperature, vibration during transportation, and circuit aging, the tilt reference 0 position and tilt sensitivity of the tilt sensor on the relative gravity meter may change. The change of the tilt reference 0 position will cause the gravity observation error to increase. The higher the tilt sensitivity, the more unstable the gravity reading will be; the lower the tilt sensitivity, the lower the resolution of the gravity observation will be.

[0005] Within a certain tilt range, the relationship between the observed value of the existing relative gravimeter and the tilt angle of the relative gravimeter is a bell-shaped curve opening downward; when the relative gravimeter is horizontal, the observed value of the relative gravimeter is the largest and is located at the apex of the bell-shaped curve.

[0006] In order to obtain accurate relative gravity observation values, the tilt reference 0 position and tilt sensitivity of the relative gravimeter must be inspected and calibrated before the gravity measurement operation begins. The two single-axis tilt sensors of the relative gravimeter are inspected and calibrated separately. When inspecting and calibrating the tilt sensor of one axis, the tilt reading of the tilt sensor of the other axis is required to remain at 0.

[0007] The existing method for calibrating the relative gravimeter tilt reference 0 position is as follows: adjust the foot screw of the relative gravimeter so that the tilt reading is 0, and read a gravity reading g0; adjust the foot screw of the relative gravimeter so that the tilt reading is -α and +α, and obtain the gravity reading g 0- and g 0+ If g0>g 0- And g0>g 0+ , g 0- ≈g 0+, the tilt reference 0 position is correct. If the tilt reference 0 position is incorrect, the inspector determines the direction of adjustment based on the inspection data obtained, estimates the size of the adjustment, and adjusts the tilt reference 0 position adjuster so that the tilt reference 0 position is at the correct position estimated by the inspector. The tilt reference 0 position is inspected and calibrated again, and this process needs to be repeated until the tilt reference 0 position is in the correct position.

[0008] The existing tilt sensitivity test method is provided by the relative gravimeter manufacturer. The specific method is as follows: after completing the tilt reference 0 position calibration, adjust the foot screw of the relative gravimeter so that the tilt sensor reading is 0 and obtain the gravity reading g0 (maximum value); adjust the foot screw of the relative gravimeter so that the tilt reading is the manufacturer's recommended value dα. r , get the gravity reading g αr The change in gravity reading dgr is the value recommended by the gravimeter manufacturer. If g0-g αr ≈dgr, indicating that the tilt sensitivity is appropriate and does not need to be calibrated. If the tilt sensitivity needs to be calibrated, the inspector determines the direction of adjustment based on the inspection data obtained, estimates the size of the adjustment, and adjusts the tilt sensitivity adjuster so that the tilt sensitivity is the correct tilt sensitivity estimated by the inspector. The tilt sensitivity is inspected and calibrated again, and this process needs to be repeated until the tilt sensitivity meets the manufacturer's recommended value.

[0009] In general, the existing tilt reference 0 position and tilt sensitivity calibration requires inspectors to estimate the adjustment direction and amount, and adopt a step-by-step approximation method to repeatedly perform inspections and calibrations, which is labor-intensive, time-consuming, and inefficient. Summary of the invention

[0010] The technical problem solved by the present invention is: to improve the deficiencies of the prior art, the present invention directly gives accurate adjustment values, quickly completes calibration, saves calibration time, and improves the efficiency of relative gravimeter tilt sensor calibration.

[0011] A relative gravimeter tilt sensor calibration method comprises the following steps:

[0012] Step 1: Preparation before calibration of relative gravity meter tilt sensor;

[0013] Step 2: Obtain a detection data set of the calibrated tilt sensor;

[0014] Step 3: Obtain the measured tilt gravity model by curve fitting using the detection data set;

[0015] Step 4: Calibrate the reference 0 position of the tilt sensor to be calibrated relative to the gravimeter;

[0016] Step 5: Perform sensitivity calibration of the tilt sensor to be calibrated relative to the gravimeter tilt.

[0017] Furthermore, the preparation before the relative gravimeter tilt calibration in step 1 refers to first setting up the relative gravimeter on stable ground or observation pier, adjusting the three foot screws of the relative gravimeter so that the readings of the two orthogonal tilt sensors are 0, and the relative gravimeter enters the measurement state, completing the preparation before calibration.

[0018] Further, the method for obtaining the detection data set of the calibrated tilt sensor in step 2 is: adjusting the foot screw of the relative gravimeter on the side corresponding to the calibrated tilt sensor so that the relative gravimeter is in different tilt states; obtaining a plurality of detected tilt readings α at a plurality of different tilt reading positions of the calibrated tilt sensor, including a position where the tilt reading is 0; t and gravity reading g t data pairs to form the detection data set.

[0019] Furthermore, the specific method of step 3 includes the following steps:

[0020] Step 31: curve fitting to obtain the measured tilt gravity model;

[0021] The commonly used method of mathematical modeling, curve fitting, is used to fit the acquired detection data set to a one-dimensional quadratic curve and establish the measured tilt gravity model:

[0022] gr=p 11 *α 2 +p 12 *α+p 13 (1)

[0023] Where:

[0024] gr is the gravity reading, the function value of the measured tilt gravity model;

[0025] α is the tilt reading, the independent variable of the measured tilt gravity model;

[0026] p11, p 12 and p 13 is the measured tilt gravity model parameter, obtained by fitting a one-dimensional quadratic curve;

[0027] Derivative the measured tilt gravity model;

[0028] Taking the derivative of equation (1), we get

[0029] gr′=2*p 11 *α+p 12 (2)

[0030] Where:

[0031] gr′ is the derivative of the measured tilt gravity model gr;

[0032] Step 32: Calculate the horizontal coordinate α0 of the vertex of the fitting curve;

[0033] The vertex of the fitting curve of the measured inclined gravity model is located at gr′=0.

[0034] gr′=2*p 11 *α+p 12 =0 (3)

[0035] Find the horizontal coordinate α0 of the vertex of the fitting curve of the measured inclined gravity model gr

[0036] α0=-p 12 / (2*p 11 ) (4)

[0037] The abscissa α0 of the vertex of the curve is the correct position of the tilt reference 0 position of the axial tilt sensor being detected.

[0038] Furthermore, the reference 0 position calibration of the calibrated tilt sensor tilted relative to the gravimeter in step 4 refers to adjusting the foot screw of the relative gravimeter on the side corresponding to the calibrated tilt sensor; making the tilt reading of the calibrated tilt sensor the horizontal coordinate α0 value of the curve vertex obtained in step 32, and then adjusting the tilt reference 0 position adjuster of the calibrated tilt sensor so that the tilt reading of the calibrated tilt sensor is 0; that is, the calibration of the tilt reference 0 position of the calibrated tilt sensor is completed.

[0039] Furthermore, the specific method of step 5 includes the following steps:

[0040] S1: calculation of horizontal coordinate translation;

[0041] After the calibration of the tilt reference 0 position of the tilt sensor being calibrated is completed, the 0 position of the horizontal coordinate is translated to the horizontal coordinate α0 of the curve vertex, indicating that the tilt reading (horizontal coordinate) collected in step 2 is also translated by α0;

[0042] Get the formula

[0043] α ts =α t -α0 (5)

[0044] Where:

[0045] α ts is the horizontal coordinate after translation;

[0046] α t is the horizontal coordinate before translation;

[0047] α0 is the horizontal coordinate translation.

[0048] S2: data for calculating tilt sensitivity;

[0049] The tilt sensitivity detection reference value provided by the relative gravimeter manufacturer includes the tilt reading change dα r and the change in gravity reading dg r .

[0050] For the measured tilt gravity model gr, the coordinates of the vertex of the fitting curve (α0, g α0 ), the tilt sensitivity detection point on the fitting curve (α r1 , g αr1 ).

[0051] g αr1 =g α0 -dg r (6)

[0052] Where:

[0053] g αr1 The gravity reading of the tilt sensitivity detection point on the fitting curve;

[0054] g α0 is the gravity reading of the coordinates of the vertices of the fitted curve;

[0055] dg r The tilt sensitivity provided by the relative gravimeter manufacturer detects the change in gravity reading from the reference value.

[0056] Tilt reading change:

[0057] dα r =|α r1 |-α0 (7)

[0058] Where:

[0059] dα r The tilt sensitivity provided by the relative gravimeter manufacturer detects the amount of change in the tilt reading from the reference value;

[0060] α r1 The gravity reading to be solved is equal to g αr1 The horizontal axis of time;

[0061] α0 is the calibrated horizontal coordinate translation of the tilt reference 0 position;

[0062] Gravity reading change:

[0063] dg r =g α0 -g αr1 (8)

[0064] Where:

[0065] dg r The tilt sensitivity provided by the relative gravimeter manufacturer detects the change in gravity reading from the reference value.

[0066] g α0 is the gravity reading of the coordinates of the vertices of the fitted curve;

[0067] g αr1 The gravity reading of the tilt sensitivity detection point on the fitting curve;

[0068] S3: Calculate the vertex function value of the fitting curve;

[0069] The measured vertical coordinate of the fitting curve vertex of the inclined gravity model gr is α0, and the formula for the function value of the fitting curve vertex is obtained:

[0070]

[0071] Where:

[0072] g α0 is the vertex function value of the fitting curve;

[0073] α0 is the horizontal coordinate of the vertex of the fitting curve;

[0074] p 11 、p 12 and p 13 are the measured tilt gravity model parameters.

[0075] S4: Calculate the horizontal coordinate α of the tilt sensitivity detection point r1 ;

[0076] The tilt sensitivity detection point function value g calculated by formula (6) is αr1 and the horizontal coordinate α of the tilt sensitivity detection point r1 Substituting into formula (1), we get the formula

[0077]

[0078] It is necessary to solve the horizontal coordinate α of the tilt sensitivity detection point in equation (10): r1 .

[0079]

[0080] set up

[0081] f=p 13 -g α0 +dg r (12)

[0082] Arranged

[0083]

[0084] The solution of formula (13) is

[0085]

[0086] S5: horizontal coordinate of the tilt sensitivity detection point solved by translation;

[0087] The horizontal coordinate solved by equation (14) needs to be translated by α0 to be consistent with the calibrated tilt reading of the tilt reference 0 position;

[0088]

[0089] Where α r11s and α r12s is the value after the horizontal coordinate is translated by α0;

[0090] Both of the horizontal coordinates of the tilt sensitivity detection points can be used to calibrate the tilt sensitivity of the tilt sensor to be calibrated. To calibrate the tilt sensitivity, only one of the horizontal coordinates of the tilt sensitivity detection points needs to be used.

[0091] S6: sensitivity calibration of the calibrated tilt sensor;

[0092] By adjusting the foot screw of the relative gravimeter on the side corresponding to the calibrated tilt sensor, the tilt reading of the calibrated tilt sensor of the relative gravimeter is α r11s or α r12s ; Then adjust the tilt sensitivity adjuster so that the tilt reading of the calibrated tilt sensor relative to the gravimeter is -dα r or dα r ; The sensitivity calibration of the calibrated tilt sensor is completed.

[0093] The advantages and beneficial effects of the present invention are:

[0094] A relative gravimeter tilt sensor calibration method of the present invention establishes a tilt gravity model of measured gravity readings and tilt readings by collecting gravity and tilt detection data sets. According to the tilt gravity model, the correct reference 0 position and the accurate position of the sensitivity of the tilt sensor are solved, and according to the solution results, the reference 0 position adjuster and the sensitivity adjuster of the tilt sensor are adjusted to achieve the calibration of the reference 0 position and the sensitivity of the tilt sensor. The present invention directly gives an accurate adjustment value, quickly completes the calibration, saves calibration time, and improves the efficiency of relative gravimeter tilt calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0095] Figure 1 is a flow chart of the present invention;

[0096] Figure 2The scatter plot and fitting curve of the data collected by the embodiment of the present invention. DETAILED DESCRIPTION

[0097] Embodiment 1, as Figure 1-2 As shown, a relative gravimeter tilt sensor calibration method comprises the following steps:

[0098] In this embodiment, step 1, preparation before calibration of the relative gravimeter tilt sensor;

[0099] Set up the relative gravimeter on stable ground or observation pier, adjust the three foot screws of the relative gravimeter so that the readings of the two orthogonal tilt sensors are 0, the relative gravimeter enters the measurement state, and the preparations before calibration are completed.

[0100] In this embodiment, step 2, obtaining a detection data set of the calibrated tilt sensor;

[0101] Adjust the foot screw of the relative gravimeter on the side corresponding to the tilt sensor to be calibrated so that the relative gravimeter is in different tilt states, including a position where the tilt reading is 0;

[0102] For example, in a relative gravity meter tilt calibration, five gravity readings are obtained at five positions where the readings of the tilt sensor being tested are -10, -5, 0, +5, and +10. The test data set is shown in Table 1;

[0103] Table 1: Collected detection datasets

[0104] <![CDATA[Inclination reading α t > <![CDATA[Gravitational reading g t > -10 2888.3276 -5 2888.3395 0 2888.3451 5 2888.3347 10 2888.3126

[0105] In this embodiment, step 3, using the detection data set to obtain the measured tilt gravity model through curve fitting;

[0106] The specific method includes the following steps:

[0107] Step 31: curve fitting to obtain the measured tilt gravity model;

[0108] The data set in Table 1 is fitted with a one-dimensional quadratic curve using the least squares curve fitting method to obtain the measured tilt gravity model applicable to the data set in Table 1:

[0109] gr=-0.0002*α 2 -0.0007*α+2888.3439

[0110] Where:

[0111] gr is the gravity reading, the function value of the measured tilt gravity model;

[0112] α is the tilt reading, the independent variable of the measured tilt gravity model;

[0113] Model parameters p11 = -0.0002, p12 = -0.0007, p13 = 2888.3439.

[0114] The measured tilt gravity model parameter values ​​obtained for different detection data sets are different;

[0115] Derivative the measured tilt gravity model;

[0116] Step 32, calculating the horizontal coordinate α0 of the vertex of the fitting curve;

[0117] Since the vertex of the fitting curve of the measured tilt gravity model is located at gr′=0, the measured tilt gravity model obtained in step 31 is derived to obtain

[0118] gr′=-0.0002*2*α-0.0007

[0119] Find the horizontal coordinate α0 of the vertex of the fitting curve of the measured inclined gravity model gr.

[0120] The position where gr′=0 is the vertex of the quadratic fitting curve.

[0121] -0.0002*2*α0-0.0007=0

[0122]

[0123] In this embodiment, step 4, calibrating the tilt sensor of the relative gravimeter to be calibrated with reference to the zero position;

[0124] By adjusting the foot screw of the relative gravity meter on the side corresponding to the calibrated tilt sensor, the tilt reading of the calibrated tilt sensor is -1.7500; then adjusting the tilt reference 0 position adjuster of the calibrated tilt sensor, the tilt reading of the calibrated tilt sensor is 0;

[0125] The calibration of the tilt reference 0 position of the tilt sensor being calibrated is completed.

[0126] In this embodiment, step 5, performing sensitivity calibration of the tilt sensor to be calibrated relative to the gravimeter;

[0127] The specific method includes the following steps:

[0128] S1: calculation of horizontal coordinate translation;

[0129] The horizontal coordinate translation amount obtained in step 32 is α0=-1.7500.

[0130] S2: data for calculating tilt sensitivity;

[0131] The coordinates of the vertex of the fitting curve (α0, gα0 ).

[0132] Tilt sensitivity detection point (α r1 , g αr1 ).

[0133] Substituting α0 = -1.7500 into equation (9), we can obtain g α0 .

[0134] g αr1 Calculated by formula (6);

[0135] In formula (6), dg r =0.0400, which is the value recommended by the gravimeter manufacturer.

[0136] α r1 is the quantity to be solved;

[0137] S3: Calculate the vertex function value of the fitting curve;

[0138] Substituting α0=-1.7500 into formula (9), we get the vertex function value g of the fitting curve α0 =2888.3445.

[0139] S4: Calculate the horizontal coordinate α of the tilt sensitivity detection point r1 ;

[0140] According to formula (12), f = p 13 -g α0 +dg r =0.0394.

[0141] According to formula (14), α r11 =-15.8921, α r12 =12.3921.

[0142] S5: horizontal coordinate of the tilt sensitivity detection point solved by translation;

[0143] According to formula (15), the horizontal coordinates of the tilt sensitivity detection points after two translations are obtained:

[0144] α r11s =-14.1421, α r12s =14.1421.

[0145] Both of the horizontal coordinates of the tilt sensitivity detection points can be used to calibrate the tilt sensitivity of the tilt sensor to be calibrated. When calibrating the tilt sensitivity, only one of the horizontal coordinates of the tilt sensitivity detection points needs to be used, and the calibration effect is the same.

[0146] S6: Sensitivity calibration of the calibrated tilt sensor:

[0147] In this embodiment, the relative gravimeter manufacturer's recommended value dαr=10 is used;

[0148] If you choose α r11s =-14.1421 for sensitivity calibration, then by adjusting the foot screw of the relative gravimeter on the side corresponding to the calibrated tilt sensor, the tilt reading of the calibrated tilt sensor relative to the gravimeter is made to be -14.1421, and adjusting the tilt sensitivity adjuster of the calibrated tilt sensor, the tilt reading of the calibrated tilt sensor relative to the gravimeter is made to be -10; the sensitivity calibration of the calibrated tilt sensor is completed.

[0149] If you choose α r12s =14.1421 for sensitivity calibration, then by adjusting the foot screw of the relative gravimeter on the side corresponding to the calibrated tilt sensor, the tilt reading of the calibrated tilt sensor relative to the gravimeter is made to be 14.1421, and adjusting the tilt sensitivity adjuster of the calibrated tilt sensor, the tilt reading of the calibrated tilt sensor relative to the gravimeter is made to be 10; the sensitivity calibration of the calibrated tilt sensor is completed.

[0150] In the above embodiment, it should be understood that only the calibration of a single axial tilt sensor on the relative gravimeter is completed. However, two uniaxial tilt sensors orthogonal to each other are installed on the relative gravimeter. Therefore, when calibrating another tilt sensor on the relative gravimeter, it is only necessary to repeat the method of steps 1-5 to complete the calibration of the other tilt sensor. The formula calculation in steps 3 and 5 in the above embodiment can be completed by writing a calculation program. It should be understood that the data collected in step 2 is input into the calculation program to obtain the abscissa α0 value of the curve vertex and the abscissa value α of the tilt sensitivity detection point. r11s and α r12s .

[0151] It should be emphasized that the embodiments of the present invention are illustrative rather than restrictive. Therefore, the present invention includes but is not limited to the embodiments described in the specific implementation modes. Any other implementation modes derived by those skilled in the art based on the technical solutions of the present invention also fall within the scope of protection of the present invention.

Claims

1. A relative gravimeter tilt sensor calibration method, characterized in that: The following steps are involved: Step 1: Preparation before calibration of relative gravity meter tilt sensor; Step 2: Obtain a detection data set of the calibrated tilt sensor; Step 3: Obtain the measured tilt gravity model by curve fitting using the detection data set; Step 4: Calibrate the reference 0 position of the tilt sensor relative to the gravimeter being calibrated; Step 5: Perform sensitivity calibration of the tilt sensor relative to the gravimeter being calibrated.

2. A relative gravimeter tilt sensor calibration method according to claim 1, characterized in that: The preparation before the relative gravimeter tilt calibration in step 1 refers to first setting up the relative gravimeter on stable ground or observation pier, adjusting the three foot screws of the relative gravimeter so that the readings of the two orthogonal tilt sensors are 0, and the relative gravimeter enters the measurement state, completing the preparation before calibration.

3. A relative gravimeter tilt sensor calibration method according to claim 1, characterized in that: The method for obtaining the detection data set of the calibrated tilt sensor in step 2 is: adjusting the foot screw of the relative gravimeter on the side corresponding to the calibrated tilt sensor so that the relative gravimeter is in different tilt states; At a plurality of different tilt reading positions of the calibrated tilt sensor, including a position where the tilt reading is 0, a plurality of tilt readings α are obtained. t and gravity reading g t data pairs to form the detection data set.

4. A relative gravimeter tilt sensor calibration method according to claim 3, characterized in that: The specific method of step 3 comprises the following steps: Step 31: curve fitting to obtain the measured tilt gravity model; Perform a one-dimensional quadratic curve fitting on the acquired detection data set to establish the measured tilt gravity model: gr=p 11 *α 2 +p 12 *α+p 13 (1) Where: gr is the gravity reading, the function value of the measured tilt gravity model; α is the tilt reading, the independent variable of the measured tilt gravity model; p 11 、p 12 and p 13 is the measured tilt gravity model parameter, obtained by fitting a one-dimensional quadratic curve; Step 32: Calculate the horizontal coordinate α0 of the vertex of the fitting curve; Derivative the measured tilt gravity model; Derivative (1) to obtain gr′=2*p 11 *α+p 12 (2) Where: gr′ is the derivative of the measured tilt gravity model gr; The vertex of the fitting curve of the measured tilt gravity model is located at gr′=0; gr′=2*p 11 *α+p 12 =0 (3) Find the horizontal coordinate α0 of the vertex of the fitting curve of the measured inclined gravity model gr α0=-p 12 / (2*p 11 ) (4) The abscissa α0 of the vertex of the curve is the correct position of the tilt reference 0 position of the axial tilt sensor being detected.

5. A relative gravimeter tilt sensor calibration method according to claim 4, characterized in that: The reference 0 position calibration of the calibrated tilt sensor of the relative gravimeter in step 4 refers to adjusting the foot screw of the relative gravimeter on the side corresponding to the calibrated tilt sensor; making the tilt reading of the calibrated tilt sensor the value of the abscissa α0 of the curve vertex obtained in step 32, and then adjusting the tilt reference 0 position regulator of the calibrated tilt sensor so that the tilt reading of the calibrated tilt sensor is 0; that is, the calibration of the tilt reference 0 position of the calibrated tilt sensor is completed.

6. A relative gravimeter tilt sensor calibration method according to claim 5, characterized in that: The specific method of step 5 comprises the following steps: S1: calculation of horizontal coordinate translation; After the calibration of the tilt reference 0 position of the tilt sensor being calibrated is completed, the 0 position of the horizontal coordinate moves to the horizontal coordinate α0 of the curve vertex, indicating that the horizontal coordinate collected in step 2 is also translated by α0; Get the formula α ts ＝α t -α0 (5) Where: α ts is the horizontal coordinate after translation; α t is the horizontal coordinate before translation; α0 is the calibrated horizontal coordinate translation of the tilt reference 0 position; S2: data for calculating tilt sensitivity; The tilt sensitivity detection reference value provided by the relative gravimeter manufacturer includes the tilt reading change dα r and the change in gravity reading dg r ; For the measured tilt gravity model gr, the coordinates of the vertex of the fitting curve (α0, g α0 ), the tilt sensitivity detection point on the fitting curve (α r1 , g αr1 ); g αr1 =g α0 -dg r (6) Where: g αr1 The gravity reading of the tilt sensitivity detection point on the fitting curve; g α0 is the gravity reading of the coordinates of the vertices of the fitted curve; dg r The tilt sensitivity detects the change in gravity reading from the reference value provided by the relative gravity meter manufacturer; Tilt reading change: dα r ＝|α r1 |-α0 (7) Where: dα r The tilt sensitivity detects the change in tilt reading from the reference value provided by the relative gravimeter manufacturer; α r1 The gravity reading to be solved is equal to g αr1 The horizontal axis of time; α0 is the calibrated horizontal coordinate translation of the tilt reference 0 position; gravity Reading change: dg r =g α0 -g αr1 (8) Where: dg r The tilt sensitivity detects the change in gravity reading from the reference value provided by the relative gravity meter manufacturer; g α0 is the gravity reading of the coordinates of the vertices of the fitted curve; g αr1 The gravity reading of the tilt sensitivity detection point on the fitting curve; S3: Calculate the vertex function value of the fitting curve; Substituting the measured horizontal coordinate α0 of the fitting curve vertex of the inclined gravity model gr into formula (1), we can obtain the formula for the function value of the fitting curve vertex: Where: g α0 is the vertex function value of the fitting curve; α0 is the horizontal coordinate of the vertex of the fitting curve; p 11 、p 12 and p 13 are the measured tilt gravity model parameters; S4: Calculate the horizontal coordinate α of the tilt sensitivity detection point r1 ; The tilt sensitivity detection point function value g calculated by formula (6) is αr1 and the horizontal coordinate α of the tilt sensitivity detection point r1 Substituting into formula (1), we get the formula It is necessary to solve the horizontal coordinate α of the tilt sensitivity detection point in equation (10): r1 ; set up f=p 13 -g α0 +dg r (12) Arranged The solution of formula (13) is S5: horizontal coordinate of the tilt sensitivity detection point solved by translation; The horizontal coordinate obtained by equation (14) needs to be translated by α0 to be consistent with the calibrated tilt reading of the tilt reference 0 position; Where α r11s or α r12s is the value after the horizontal coordinate is translated by α0; S6: sensitivity calibration of the calibrated tilt sensor; By adjusting the foot screw of the relative gravimeter on the side corresponding to the calibrated tilt sensor, the tilt reading of the calibrated tilt sensor of the relative gravimeter is α r11s or α r12s ; Then adjust the tilt sensitivity adjuster so that the tilt reading of the calibrated tilt sensor relative to the gravimeter is -dα r or dα r ; That is, the sensitivity calibration of the calibrated tilt sensor is completed.

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