阅读说明：本技术 一种重力仪安装误差角标定方法 (Method for calibrating installation error angle of gravimeter ) 是由 吴畏 王智奇 朱学毅 仇恺 褚宁 宋丽薇 谭志军 吴宗坤 于 2021-06-23 设计创作，主要内容包括：本发明涉及一种重力仪安装误差角标定方法,步骤为：1、进行标定测试前的准备工作；2、调整调平支架改变重力仪倾斜角度,记录下在三个X轴角度位置对应的敏感器输出电压值V-(Xi),i＝1,2,3；3、计算出X轴方向安装误差角θ-X；4、重复步骤2和3测量N次,N≥5,计算出X轴方向平均安装误差角5、调整调平支架改变重力仪倾斜角度,记录下三个Y轴角度位置对应的敏感器输出电压值V-(Yi),i＝1,2,3；6、计算出Y轴方向安装误差角θ-Y；7、重复步骤5和6测量N次,N≥5,计算出Y轴方向平均安装误差角本发明可以快速测量并计算出重力仪安装误差角。(The invention relates to a method for calibrating an installation error angle of a gravimeter, which comprises the following steps: 1. carrying out preparation work before calibration test; 2. adjusting the leveling bracket to change the inclination angle of the gravimeter, and recording output voltage values V of the sensor corresponding to the three X-axis angle positions Xi I is 1,2, 3; 3. calculating the installation error angle theta in the X-axis direction X (ii) a 4. Repeating the steps 2 and 3 to measure N times, wherein N is more than or equal to 5, and calculating the average installation error angle in the X-axis direction 5. Adjusting the leveling support to change the inclination angle of the gravimeter, and recording output voltage values V of the sensors corresponding to the three Y-axis angle positions Yi I is 1,2, 3; 6. calculating the installation error angle theta in the Y-axis direction Y (ii) a 7. Repeating the steps 5 and 6 to measure N times, wherein N is more than or equal to 5, and calculating the average installation error angle in the Y-axis direction The invention can quickly measure and countAnd calculating the installation error angle of the gravimeter.)

1. A gravity meter installation error angle calibration method is characterized in that: the method comprises the following steps:

step one, carrying out preparation work before a calibration test, specifically: fixing a gravimeter probe and an inclination sensor together, and fastening the gravimeter probe and the inclination sensor together in a gravimeter case, wherein the gravimeter is arranged on a leveling bracket, the inclination angle of the gravimeter can be changed along with the leveling bracket, and the inclination sensor is used for measuring the inclination angle of the gravimeter in real time; after the gravity meter is installed, starting the gravity meter, observing that the gravity value is stably output, and then starting a calibration test;

step two: adjusting the leveling support to change the inclination angle of the gravimeter, so that the output value of an inclination sensor fixed together with the gravimeter probe meets the following requirements: the X-axis readings are respectively alpha₁、α₂、α₃In which α is₂＝0°±0.001°，α₁And alpha₃Are equal in absolute value, one is positive and one is negative, α₁And alpha₃The precision of the X-axis is +/-0.001 degrees, and the reading of the Y-axis is beta epsilon (-0.001 degrees and 0.001 degrees); after the sensor outputs stably, recording the output voltage value V of the sensor corresponding to each X-axis angle position_Xi，i＝1,2,3；

Step three: calculating the installation error angle theta in the X-axis direction_XThe concrete formula is as follows;

step (ii) ofFourthly, the method comprises the following steps: repeating the second step and the third step to measure N times, wherein N is more than or equal to 5, and calculating the average installation error angle in the X-axis directionThe concrete formula is as follows:

step five: adjusting the leveling support to change the inclination angle of the gravimeter, so that the output value of an inclination sensor fixed together with the gravimeter probe meets the following requirements: the X-axis readings are alpha epsilon (-0.001 degrees and 0.001 degrees), and the Y-axis readings are beta respectively₁、β₂And beta₃，β₂＝0°±0.001°，β₁And beta₃The absolute values of the readings are equal, one is positive and one is negative, beta₁And beta₃The accuracy of the sensor is +/-0.001 degrees, and the sensor output is stable; recording the output voltage value V of the sensor corresponding to each Y-axis angle position_Yi，i＝1,2,3；

Step six: calculating the installation error angle theta in the Y-axis direction_YThe concrete formula is as follows;

step seven: repeating the fifth step and the sixth step to measure N times, wherein N is more than or equal to 5, and calculating the average installation error angle in the Y-axis directionThe concrete formula is as follows:

2. the gravimeter installation error angle calibration method according to claim 1, characterized in that: alpha is alpha₁And alpha₃The reading values of (A) are respectively: alpha is alpha₁2.5 ° ± 0.001 ° and α₃＝2.5°±0.001°。

3. The gravimeter installation error angle calibration method according to claim 1, characterized in that: the repetition times in the fourth step are 7 times.

4. The gravimeter installation error angle calibration method according to claim 1, characterized in that: step five is beta₁And beta₃The reading values of (A) are respectively: beta is a₁2.5 ° ± 0.001 ° and β₃＝2.5°±0.001°。

5. The gravimeter installation error angle calibration method according to claim 1, characterized in that: the number of repetitions in step seven was 7.

Technical Field

The invention belongs to the field of gravity acceleration measuring instruments, and particularly relates to a method for calibrating an installation error angle of a gravimeter.

Background

The gravity acceleration g is a basic geophysical constant, but can change along with factors such as geology of the terrain, altitude, moon position and the like, and the accurate measurement of the gravity acceleration has very important significance in the fields of geoscience, resource exploration, national defense construction and the like. The special equipment for measuring the gravity acceleration is called a gravimeter, and in order to accurately measure the value of the gravity acceleration, the direction of a sensitive axis of the gravimeter needs to be consistent with the direction of the gravity acceleration g as much as possible. However, a gravity sensing element (also called a probe) of the gravity meter is installed inside the gravity meter, and due to the processing precision and installation error of parts, an error angle exists between the position direction of the gravity meter after vertical leveling and the gravity sensing axis direction, which is called as an installation error angle in the industry. The existence of the installation error angle can generate great influence on the scale factor (or lattice value) and the initial zero position of the gravity meter, thereby bringing about system errors and reducing the measurement precision of the gravity meter.

In order to solve the problem, the installation error angle of the gravity meter needs to be accurately measured and compensated into the initial angle value of the leveling link of the gravity meter, so that the sensitive axis direction of the gravity meter is coincided with the gravity acceleration direction when the gravity meter is in a working state. The invention provides a simple and feasible method for calibrating the installation error angle of the gravimeter, which can quickly measure and calculate the installation error angle of the gravimeter, and is convenient and simple and high in measurement precision.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, and provides a simple and easy method for calibrating the installation error angle of the gravimeter, which can quickly measure and calculate the installation error angle of the gravimeter for compensating the measurement error, thereby improving the measurement precision of the gravimeter.

The above object of the present invention is achieved by the following technical solutions:

a gravity meter installation error angle calibration method is characterized in that: the method comprises the following steps:

step one, preparation work before calibration test is carried out: fixing a gravimeter probe and an inclination sensor together, and fastening the gravimeter probe and the inclination sensor together in a gravimeter case, wherein the gravimeter is arranged on a leveling bracket, the inclination angle of the gravimeter can be changed along with the leveling bracket, and the inclination sensor is used for measuring the inclination angle of the gravimeter in real time; after the gravity meter is installed, starting the gravity meter, observing that the gravity value is stably output, and then starting a calibration test;

step two: adjusting the leveling support to change the inclination angle of the gravimeter, so that the output value of an inclination sensor fixed together with the gravimeter probe meets the following requirements: the X-axis readings are respectively alpha₁、α₂、α₃In which α is₂＝0°±0.001°，α₁And alpha₃Are equal in absolute value, one is positive and one is negative, α₁And alpha₃The precision of the angle is +/-0.001 degrees; the Y-axis reading is beta epsilon (-0.001 degrees, 0.001 degrees); after the sensor outputs stably, recording the output voltage value V of the sensor corresponding to each X-axis angle position_Xi，i＝1,2,3；

Step three: calculating the installation error angle theta in the X-axis direction_XThe concrete formula is as follows;

step four: repeating the second step and the third step to measure N times, wherein N is more than or equal to 5, and calculating the average installation error angle in the X-axis directionThe concrete formula is

Step five: adjusting the leveling support to change the inclination angle of the gravimeter, so that the output value of an inclination sensor fixed together with the gravimeter probe meets the following requirements: the X-axis readings are alpha epsilon (-0.001 degrees and 0.001 degrees), and the Y-axis readings are beta respectively₁、β₂And beta₃，β₂＝0°±0.001°，β₁And beta₃The absolute values of the readings are equal, one is positive and one is negative, beta₁And beta₃The accuracy of the sensor is +/-0.001 degrees, and the sensor output is stable; recording the output voltage value V of the sensor corresponding to each Y-axis angle position_Yi，i＝1,2,3；

Step six: calculating the installation error angle theta in the Y-axis direction_YThe concrete formula is as follows;

step seven: repeating the fifth step and the sixth step to measure N times, wherein N is more than or equal to 5, and calculating the average installation error angle in the Y-axis directionThe concrete formula is as follows:

further: in step two,. alpha.₁And alpha₃The reading values of (A) are respectively: alpha is alpha₁2.5 ° ± 0.001 ° and α₃＝2.5°±0.001°。

Further: the repetition times in the fourth step are 7 times.

Further: step five is beta₁And beta₃The reading values of (A) are respectively: beta is a₁2.5 ° ± 0.001 ° and β₃＝2.5°±0.001°。

Further: the number of repetitions in step seven was 7.

The invention has the advantages and positive effects that:

the method for calibrating the installation error angle of the gravimeter can quickly measure and calculate the installation error angle of the gravimeter without the assistance of additional instruments and equipment, and is convenient, simple and high in measurement precision. The device is not limited by the probe principle and can be widely applied to various gravimeters.

Drawings

FIG. 1 is a schematic view of a gravity meter mounting structure

FIG. 2 is a diagram of a gravimeter coordinate axis and error angle calculation model.

Detailed Description

The structure of the present invention will be further described by way of examples with reference to the accompanying drawings. It is to be understood that this embodiment is illustrative and not restrictive.

The structure of the embodiment is as shown in fig. 1, a gravity meter probe 1 and an inclination sensor 2 are fixed together and fastened in a gravity meter case 3, a gravity meter is installed on a leveling bracket 4, the inclination angle of the gravity meter can be changed along with the leveling bracket, and the inclination sensor can measure the inclination angle of the gravity meter in real time.

A calculation model of a sensitive axis, a horizontal plane coordinate axis and an installation error angle of the gravimeter is shown in FIG. 2, an X axis and a Y axis are defined to be coincident with an axis of an inclination sensor X, Y, the axes are positioned on a horizontal plane and are mutually vertical, a Z axis is collinear with a gravity acceleration g but has opposite directions, and error angles between the sensitive axis of the gravimeter and the X axis and the Y axis are theta respectively_XAnd theta_YI.e. the installation error angle of the gravimeter.

During calibration test:

firstly, normally installing and starting a gravimeter, observing stable output of a gravity value, and then starting a calibration test; then adjust the leveling support and change the inclination angle of the gravimeter, so that the output value of the inclination sensor meets the following requirements: the X-axis readings are respectively alpha₁、α₂、α₃In which α is₂＝0°±0.001°，α₁And alpha₃Are equal in absolute value, one is positive and one is negative, α₁And alpha₃The precision of the angle is +/-0.001 degrees; the Y-axis reads β ∈ (-0.001 °, 0.001 °). In the present embodiment, α₁And alpha₃The reading values of (A) are respectively preferredComprises the following steps: alpha is alpha₁2.5 ° ± 0.001 ° and α₃2.5 ° ± 0.001 °. Recording the output voltage value V of each angle position sensor after the output of the sensor is stable_Xi，i＝1,2,3。

Output voltage V of gravity sensor_XiAngle of error theta from installation_XThe following relationship is satisfied:

V_Xi＝K[g₀-(g-gcos(θ_X+α_i))]

in the formula:

k-gravimeter scale factor;

g₀-initial gravity output (also known as zero offset) of the gravimeter;

g-gravitational acceleration value at the calibration position;

α_i-the tilt sensor X-axis tilt output during calibration.

The output values of the sensor under two continuous different inclination angles are differenced to obtain the output variation quantity delta V of the sensor_XiComprises the following steps:

the above formula includes a gravimeter scale factor K and an installation error angle theta_XTwo variables need to be solved by two equations simultaneously, so that the output value V of the sensor under three different inclination angles is continuously measured_X1、V_X2And V_X3Obtaining the output variable quantity delta V of the two sensors_X2And Δ V_X3And, the two are divided to obtain:

thereby obtaining the installation error angle theta of the gravimeter in the X-axis direction_XThe calculation formula is as follows:

the average value is obtained by repeating the measurement for N times, wherein N is more than or equal to 5, in the embodiment, N is 7, and the average installation error angle in the X-axis direction is obtainedComprises the following steps:

in a similar way, the leveling bracket is adjusted to change the inclination angle of the gravity meter, so that the output value of the inclination sensor meets the following requirements: the X-axis readings alpha epsilon (-0.001 DEG, 0.001 DEG), and the Y-axis readings are respectively beta₁、β₂And beta₃，β₂＝0°±0.001°，β₁And beta₃The absolute values of the readings are equal, one is positive and one is negative, beta₁And beta₃The accuracy of (2) is +/-0.001 degrees. In this embodiment, β₁And beta₃The respective reading values of (a) are preferably: beta is a₁2.5 ° ± 0.001 ° and β₃2.5 ° ± 0.001 °. Recording the output voltage value V of each angle position sensor after the output of the sensor is stable_YiI is 1,2, 3; can obtain the installation error angle theta of the gravimeter in the Y-axis direction_YAnd Y-axis direction average mounting error angleThe concrete formula is as follows:

therefore, the installation error angle of the gravimeter X, Y in the axial direction is calibrated and respectively compensated into the initial angle value of the gravimeter leveling link, so that the sensitive axial direction and the gravity acceleration direction can be coincided when the gravimeter is in the working state.

As described aboveInclination angle alpha of X axis and Y axis_iAnd beta_iThe values are not limited to the values described above and may be any suitable angle within the normal operating range of the gravimeter.

Although the embodiments of the present invention and the accompanying drawings are disclosed for illustrative purposes, those skilled in the art will appreciate that: various substitutions, changes and modifications are possible without departing from the spirit of the invention and the scope of the appended claims, and therefore the scope of the invention is not limited to the disclosure of the embodiments and the accompanying drawings.