Method for establishing high-precision measurement reference for unmanned platform gravimeter

Abstract

The present disclosure relates to the field of high-precision measurement for an inertial measurement unit of an unmanned platform gravimeter, and in particular to a method for establishing a high-precision measurement reference for the unmanned platform gravimeter capable of identifying and eliminating inconsistency between a gravimeter inertial assembly and a platform body physical reference, supporting a gravimeter to achieve establishment of a system-level measurement reference, laying a foundation for gravity measurement under small-carrier and high-dynamic conditions, and improving the dynamic environment adaptability and measurement precision of the gravimeter. The method provided in the present disclosure for performing high-precision calibration and compensation on an inconsistency error between an inertial assembly coordinate system of the unmanned platform gravimeter and a mechanical platform body coordinate system on the basis of a low-precision single-axis rotary table enables the identification and compensation of the inconsistency error between the inertial assembly coordinate system and the mechanical platform body coordinate system in laboratory or quiet field ground conditions, establishing a high-precision measurement reference for the gravimeter. The mechanical machining cost of the gravimeter is reduced, and the long-term precision of gravity measurement under the small-carrier and high-dynamic conditions is guaranteed.

Description

A method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter

[0001] Related applications

[0002] This application claims priority to Chinese Patent Application No. 202410560868.0, filed on May 8, 2024, and incorporates the entire contents of the aforementioned patent application as part of this application. Technical Field

[0003] This disclosure pertains to the field of high-precision measurement of inertial measurement units for unmanned platform gravimeters, and specifically relates to a method for establishing a high-precision measurement benchmark for unmanned platform gravimeters that can identify and eliminate inconsistencies between the inertial components of the gravimeter and the physical reference of the platform, supporting the establishment of a system-level measurement benchmark for the gravimeter, laying the foundation for gravity measurement under small-carrier, high-dynamic conditions, and improving the dynamic environmental adaptability and measurement accuracy of the gravimeter. Background Technology

[0004] The main measurement component of the gravimeter includes an inertial measurement unit (IMU) and an inertial stabilization platform. The IMU comprises three single-axis fiber optic gyroscopes, two horizontal accelerometers, and one vertical gravity sensor. The gravity sensor also functions as a vertical accelerometer. To meet the stringent size and weight requirements of small vehicles such as unmanned surface vessels (USVs), autonomous underwater vehicles (AUVs), and drones, the gravimeter does not employ a three-ring inertial platform design but instead utilizes a more compact azimuth strapdown inertial platform. Structurally, the gravimeter platform consists of two horizontal gimbal frames, with no gimbal frame structure in the azimuth direction. The IMU is integrated within the two horizontal gimbal frames, thus forming the azimuth strapdown inertial platform. The platform's mechanical components consist of a base, an outer frame Q, and an inner frame P. Three gyroscopes G are orthogonally mounted on the inner frame. x G y G z and accelerometer A x A y and gravity sensor A z The inertial measurement unit (IMU) is integrally mounted within the platform's internal frame, with the outer frame serving as the pitch ring and the inner frame as the roll ring. Functionally, the platform's horizontal stabilization loop utilizes fiber optic gyroscope-based stabilization technology to stabilize the inertial frame in the two horizontal degrees of freedom, isolating the carrier's horizontal angular motion. The correction loop uses navigation calculations to control the azimuth strapdown platform to track the local geographic level, ensuring that the gravity sensor's input axis is strictly parallel to the geographic vertical, thus directly measuring vertical acceleration—that is, measuring raw gravity information.

[0005] During the carrier's movement, the azimuth strapdown inertial platform dynamically tracks the local geographic level in real time. Simultaneously, based on the output information of the azimuth fiber optic gyroscope and the carrier's motion information, the platform's azimuth angle is calculated, providing a physical measurement reference for the gravity sensor. Compared to a three-loop inertial platform that completely isolates the carrier's angular motion, the azimuth strapdown inertial platform lacks an azimuth loop and does not isolate the carrier's angular motion. When unmanned platform gravimeters are used to perform gravity measurements on small carriers such as unmanned surface vessels, AUVs, and drones, the small size and light weight of the carrier, coupled with disturbances such as gusts of wind, waves, and currents, cause significant angular motions in roll, pitch, and heading, creating dynamic interference with gravity measurements. Because the calibration accuracy of the gravimeter's inertial components and the machining accuracy of the platform cannot achieve ideal error-free operation, and because the precision shaft structure of the two horizontal universal joint frames of the inertial platform is susceptible to vibration and impact, the mechanical platform coordinate system of the azimuth strapdown inertial platform is usually not coincident with the inertial component coordinate system. Under the action of the azimuth angular rate input, the horizontal loop stabilization loop will couple the azimuth angular rate, causing the platform to tilt and resulting in measurement errors in the gravity sensor. Demonstration and actual gravity measurement experiments have verified that, under typical high-dynamic measurement conditions, the consistency between the gravimeter's inertial component coordinate system and the mechanical platform coordinate system should be better than 10″. Therefore, to ensure that the gravimeter maintains a high-precision measurement reference under dynamic conditions, the azimuth strapdown inertial platform technical solution places high demands on the calibration accuracy of the gravimeter's inertial components and the machining accuracy of the platform.

[0006] Currently, with the support of a high-precision turntable, the calibration accuracy of the inertial component installation error can reach better than 2″ (i.e., 2 arcseconds), and its impact on the consistency between the inertial component coordinate system and the mechanical table coordinate system is negligible. Therefore, the inconsistency between the inertial component coordinate system and the mechanical table coordinate system is mainly determined by the machining accuracy of the platform and the precision of the precision shaft system structure of the two horizontal universal joints. To ensure the requirement of better than 10″ (i.e., 10 arcseconds), the machining accuracy of the platform and inertial components, as well as the precision of the precision shaft system structure of the two horizontal universal joints, must all reach at least better than 5″ (i.e., 5 arcseconds). This directly increases the machining difficulty and cost of the gravimeter. This allows gravimeter products to gain a price advantage in market competition. However, even if machining meets the required specifications, the long-term accuracy of the horizontal universal joint's precision shaft system cannot be reliably guaranteed. After prolonged measurement operations, the possibility of measurement errors introduced by this issue still exists. Currently, no effective solutions or relevant research results have been found to address this problem. Therefore, it is urgent to find technical means to ensure the consistency between the coordinate system of the gravimeter's inertial components and the coordinate system of the mechanical platform without relying entirely on high-precision machining, to establish a high-precision measurement benchmark for the gravimeter, and to ensure long-term gravity measurement accuracy under small-scale, high-dynamic conditions while reducing the machining cost of the gravimeter.

[0007] Summary of the Invention

[0008] This disclosure aims to address related technical issues by proposing a method for high-precision calibration and compensation of inconsistency errors between the inertial component coordinate system and the mechanical platform coordinate system of an unmanned platform gravimeter, based on a low-precision single-axis turntable. This method enables the unmanned platform gravimeter to calibrate and compensate for inconsistencies between the inertial component coordinate system and the mechanical platform coordinate system under quiet ground conditions in a laboratory or field, using a fixed-angle rotation method. This reduces the machining cost of the gravimeter while ensuring long-term accuracy of gravity measurements under small-scale, high-dynamic conditions.

[0009] To solve the above-mentioned technical problems, the present disclosure adopts the following technical solution.

[0010] A method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter includes the following steps:

[0011] S1. Place the gravimeter on the preset single-axis turntable, start the gravimeter, and preheat it. During the preheating process, the two horizontal loop stabilization loops of the gravimeter's inertial platform are in a closed loop state, and the correction loop works in the fine alignment mode.

[0012] S2. Statically record the raw pulse information output by the horizontal accelerometer and gravity sensor, switch the gravimeter inertial platform correction loop to inertial navigation mode, and rotate the single-axis turntable 90°. After the rotation is completed, statically record the raw pulse information output by the horizontal accelerometer and gravity sensor.

[0013] S3. Identify the inconsistency error between the inertial component coordinate system and the mechanical table coordinate system based on the changes in the outer and inner frame angles corresponding to the original pulse information recorded before and after rotation.

[0014] S4. Adjust the installation error of the inertial measurement unit based on the identified inconsistency error angle to compensate for the inconsistency error between the coordinate system of the inertial component and the coordinate system of the mechanical table.

[0015] S5. The newly identified error matrix between the input axis coordinate system of the gyroscope component and the coordinate system of the inertial component is bound to the two horizontal loop stabilization loop control program of the gravimeter inertial platform. The single-axis turntable is rotated -90° and returned to the initial position of the turntable. The correction loop of the gravimeter inertial platform is switched to the fine alignment mode to maintain fine alignment.

[0016] S6. Repeat steps S2 to S5 until the values ​​of the inconsistency error angles between the inertial component coordinate system and the mechanical platform coordinate system are all less than 5″. Then, bind the installation error matrix between the gyroscope component input axis coordinate system and the inertial component coordinate system into the two horizontal loop stabilization loop control program of the gravimeter inertial platform. This completes the high-precision calibration and compensation of the inconsistency error between the inertial component coordinate system and the mechanical platform coordinate system, and establishes a high-precision measurement benchmark for the gravimeter.

[0017] Furthermore, in step S1, the preset single-axis turntable repeatability is better than 0.1°, and the continuous rotation along the vertical direction is more than 90°.

[0018] Furthermore, in step S1, the preheating time is 24 hours.

[0019] Furthermore, in step S2, the angular rate at which the single-axis turntable rotates 90° is less than 20° / s.

[0020] Furthermore, in step S2, the static admission time is 2 minutes.

[0021] Furthermore, the method for step S3 is as follows:

[0022] S31. Define the horizontal accelerometer A before rotation. x A y and gravity sensor A z The mean vector of the output raw pulse is E1 = [E x1 E y1 E z1 After rotation, horizontal accelerometer A x A y and gravity sensor A z The mean vector of the output original pulse is E2 = [E x2 E y2 E z2 ], where E x1 E y1 E z1 For the horizontal accelerometer A before rotation x A y and gravity sensor A z The mean value of the original output pulse, E x2 E y2 E z2 The horizontal accelerometer A after rotation x A y and gravity sensor A z The mean value of the original output pulse;

[0023] S32. Define the scale factor matrix of the accelerometer assembly consisting of the horizontal accelerometer and the gravity sensor as K.A The zero-partial matrix is ​​B A The installation error matrix is ​​S A K A B A S A All of these are known quantities obtained from the factory calibration of the gravimeter;

[0024] S33. Define horizontal accelerometer A before rotation. x A y and gravity sensor A z The output acceleration vector is A1 = [A 1x A 1y A 1z After rotation, horizontal accelerometer A x A y and gravity sensor A z The output acceleration vector is A2 = [A 2x A 2y A 2z ], then A1 = K A S A (E1-B A A2 = K A S A (E2-B A );

[0025] S34. The local gravitational acceleration is g, and the corresponding angle changes of the platform's outer frame before and after rotation are dA. Q The corresponding angle changes of the inner frame of the platform before and after rotation are dA. P Then we can obtain:

[0026] The inconsistency errors between the inertial component coordinate system and the mechanical table coordinate system were obtained by measuring the angular changes of the outer and inner frames of the platform before and after rotation:

[0027] dA Q dA P The unit is arcsecond, dG x dG represents the inconsistency angle between the z-axis of the inertial component coordinate system and the y-axis of the mechanical table coordinate system. y The angle representing the inconsistency error between the z-axis of the inertial component coordinate system and the x-axis of the mechanical table coordinate system.

[0028] Furthermore, the method for step S4 is as follows:

[0029] S41. Define the gyroscope G x G y G z The installation error matrix between the input axis coordinate system of the gyroscope assembly and the coordinate system of the inertial assembly is S.G S G The known quantity is obtained from the factory calibration of the gravimeter; S G The expression is:

[0030] Where S Gxy S is the inconsistency angle between the y-axis of the gyroscope component's input axis coordinate system and the x-axis of the inertial component's coordinate system. Gxz S is the inconsistency angle between the z-axis of the gyroscope component's input axis coordinate system and the x-axis of the inertial component's coordinate system. Gyz The inconsistency error angle between the z-axis of the input axis coordinate system of the gyroscope component and the y-axis of the inertial component coordinate system;

[0031] S42.Use dG x dG y For S G Compensation is performed to obtain the new installation error matrix S between the gyroscope component input axis coordinate system and the inertial component coordinate system after compensation. G ′, S G The expression is:

[0032] Furthermore, the alignment time in step S5 is maintained at 20 minutes.

[0033] The beneficial effects of this disclosure are as follows:

[0034] The method proposed in this disclosure for high-precision calibration and compensation of inconsistency errors between the inertial component coordinate system and the mechanical platform coordinate system of an unmanned platform gravimeter based on a low-precision single-axis turntable can identify and compensate for inconsistencies between the inertial component coordinate system and the mechanical platform coordinate system under quiet ground conditions in the laboratory or field, establishing a high-precision measurement benchmark for the gravimeter. This reduces the machining cost of the gravimeter while ensuring long-term accuracy of gravity measurements under small-scale, high-dynamic conditions. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 is a flowchart of this disclosure. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this disclosure clearer, the technical solutions of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure. The following embodiments are used to illustrate this disclosure but should not be used to limit its scope.

[0038] The present disclosure is described below with reference to Figure 1 in the specification.

[0039] The first step in the implementation process is to prepare a single-axis turntable with a repeatability accuracy better than 0.1° and the ability to rotate continuously by more than 90° in the vertical direction. Place the unmanned platform gravimeter on the single-axis turntable, start the gravimeter, and preheat it for 24 hours. During the preheating process, the two horizontal loop stabilization loops of the gravimeter's inertial platform are in a closed loop state, and the correction loop works in the precision alignment mode.

[0040] The second step in the implementation process is to statically record the raw pulse information output by the horizontal accelerometer and gravity sensor for 2 minutes. Then, the gravimeter inertial platform correction loop is switched to inertial navigation mode, and the single-axis turntable is immediately rotated 90° at an angular rate not exceeding 20° / s. After the rotation is completed, the raw pulse information output by the horizontal accelerometer and gravity sensor is statically recorded for 2 minutes.

[0041] The third step in the implementation process: Based on the changes in the outer and inner frame angles corresponding to the 2-minute raw pulse information recorded before and after rotation, the inconsistency error between the inertial component coordinate system and the mechanical table coordinate system is identified. The detailed process is as follows:

[0042] Assume horizontal accelerometer A before and after rotation x A y and gravity sensor A z The mean vectors of the output 2-minute raw pulses are E1=[E x1 E y1 E z1 ] and E2 = [E x2 E y2 E z2 ]. Among them, E x1 E y1 E z1 With E x2 E y2 E z2 The horizontal accelerometers A before and after rotation are respectively. x A y and gravity sensor A zThe average of the 2-minute raw pulse output. Assume the scaling factor matrix of the accelerometer assembly consisting of the horizontal accelerometer and gravity sensor is K. A The zero-partial matrix is ​​B A The installation error matrix is ​​S A Among them, K A B A S A All of these are known quantities obtained during the gravimeter's development and factory calibration. Assume the horizontal accelerometer A before and after rotation... x A y and gravity sensor A z The output acceleration vectors are A1 = [A 1x A 1y A 1z A2 = [A] 2x A 2y A 2z Then A1 = K A S A (E1-B A A2 = K A S A (E2-B A Furthermore, assuming the local gravitational acceleration is g, the corresponding angle change of the platform's outer frame before and after rotation is dA. Q The corresponding angle changes of the inner frame of the platform before and after rotation are dA. P ,

[0043] The inconsistency errors between the inertial component coordinate system and the mechanical table coordinate system can be identified by the angular changes corresponding to the outer and inner frames of the platform before and after rotation:

[0044] In formulas (3) and (4), dA Q dA P The unit is arcsecond, dG x dG represents the inconsistency angle between the z-axis of the inertial component coordinate system and the y-axis of the mechanical table coordinate system. y The angle representing the inconsistency error between the z-axis of the inertial component coordinate system and the x-axis of the mechanical table coordinate system.

[0045] The fourth step in the implementation process is to adjust the installation error of the inertial measurement unit (IMU) based on the identified inconsistency error angle, compensating for the inconsistency error between the IMU coordinate system and the mechanical platform coordinate system. The detailed process is as follows:

[0046] Assuming gyroscope G x G y G zThe installation error matrix between the input axis coordinate system of the gyroscope assembly and the coordinate system of the inertial assembly is S. G S G S is a known quantity obtained through factory calibration during the development of the gravimeter. G The expression is:

[0047] Among them, S Gxy S is the inconsistency angle between the y-axis of the gyroscope component's input axis coordinate system and the x-axis of the inertial component's coordinate system. Gxz S is the inconsistency angle between the z-axis of the gyroscope component's input axis coordinate system and the x-axis of the inertial component's coordinate system. Gyz The inconsistency error angle between the z-axis of the input axis coordinate system of the gyroscope component and the y-axis of the inertial component coordinate system;

[0048] Using dG x dG y For S G Compensation is performed to obtain the new installation error matrix S between the gyroscope component input axis coordinate system and the inertial component coordinate system after compensation. G ′, S G The expression is:

[0049] Step 5 of the implementation process: Install the error matrix S between the newly identified gyroscope component input axis coordinate system and the inertial component coordinate system. G The data is then bound (i.e. updated) to the two-horizontal-loop stabilization control program of the gravimeter inertial platform. The single-axis turntable is rotated -90° to return to its initial position. The gravimeter inertial platform correction loop is switched to fine alignment mode and maintained in fine alignment for 20 minutes.

[0050] Step 6 of the implementation process: Repeat steps 2 through 5 of the implementation process until the obtained dG is obtained. x dG y The values ​​are all less than 5″. The installation error matrix S between the gyroscope component input axis coordinate system and the inertial component coordinate system obtained at this time is... G By binding the data into the two-horizontal-loop stabilization control program of the gravimeter inertial platform, the high-precision calibration and compensation of the inconsistency error between the inertial component coordinate system and the mechanical platform coordinate system is completed, and a high-precision measurement benchmark for the gravimeter is established.

[0051] The method proposed in this disclosure for high-precision calibration and compensation of inconsistency errors between the inertial component coordinate system and the mechanical platform coordinate system of an unmanned platform gravimeter based on a low-precision single-axis turntable can identify and compensate for inconsistencies between the inertial component coordinate system and the mechanical platform coordinate system under quiet ground conditions in the laboratory or field, establishing a high-precision measurement benchmark for the gravimeter. This reduces the machining cost of the gravimeter while ensuring long-term accuracy of gravity measurements under small-scale, high-dynamic conditions.

[0052] The above are merely preferred embodiments of this disclosure. It should be noted that for those skilled in the art, several improvements can be made without departing from the principles of this disclosure and should also be considered within the scope of protection of this disclosure.

Claims

1. A method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter, characterized in that, Includes the following steps: S1. Place the gravimeter on a preset single-axis turntable, start the gravimeter, and preheat it. During the preheating process, the two horizontal loop stabilization loops of the gravimeter's inertial platform are in a closed loop state, and the correction loop works in the fine alignment mode. S2. Statically record the raw pulse information output by the horizontal accelerometer and gravity sensor, switch the gravimeter inertial platform correction loop to inertial navigation mode, and rotate the single-axis turntable 90°. After the rotation is completed, statically record the raw pulse information output by the horizontal accelerometer and gravity sensor. S3. Identify the inconsistency error between the inertial component coordinate system and the mechanical table coordinate system based on the changes in the outer and inner frame angles corresponding to the original pulse information recorded before and after rotation. S4. Adjust the installation error of the inertial measurement unit based on the identified inconsistency error angle to compensate for the inconsistency error between the coordinate system of the inertial component and the coordinate system of the mechanical table. S5. The newly identified error matrix between the input axis coordinate system of the gyroscope component and the coordinate system of the inertial component is bound to the two horizontal loop stabilization loop control program of the gravimeter inertial platform. The single-axis turntable is rotated -90° and returned to the initial position of the turntable. The correction loop of the gravimeter inertial platform is switched to the fine alignment mode to maintain fine alignment. S6. Repeat steps S2 to S5 until the values ​​of the inconsistency error angles between the inertial component coordinate system and the mechanical platform coordinate system are all less than 5″. Then, bind the installation error matrix between the gyroscope component input axis coordinate system and the inertial component coordinate system into the two-horizontal-loop stabilization control program of the gravimeter inertial platform. This completes the high-precision calibration and compensation of the inconsistency error between the inertial component coordinate system and the mechanical platform coordinate system, and establishes a high-precision measurement benchmark for the gravimeter.

2. The method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter according to claim 1, characterized in that, In step S1, the preset repeatability of the single-axis turntable is better than 0.1°, and the continuous rotation along the vertical direction is more than 90°.

3. The method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter according to claim 1, characterized in that, In step S1, the preheating time is 24 hours.

4. The method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter according to claim 1, characterized in that, In step S2, the angular rate at which the single-axis turntable rotates 90° is less than 20° / s.

5. The method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter according to claim 1, characterized in that, In step S2, the static admission time is 2 minutes.

6. A method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter according to any one of claims 1 to 5, characterized in that, The method for step S3 is as follows: S31. Define the horizontal accelerometer A before rotation. x A y and gravity sensor A z The mean vector of the output raw pulse is E1 = [E x1 E y1 E z1 After rotation, horizontal accelerometer A x A y and gravity sensor A z The mean vector of the output original pulse is E2 = [E x2 E y2 E z2 ], where E x1 E y1 E z1 For the horizontal accelerometer A before rotation x A y and gravity sensor A z The mean value of the original output pulse, E x2 E y2 E z2 The horizontal accelerometer A after rotation x A y and gravity sensor A z The mean value of the original output pulse; S32. Define the scale factor matrix of the accelerometer assembly consisting of the horizontal accelerometer and the gravity sensor as K. A The zero-partial matrix is ​​B A The installation error matrix is ​​S A K A B A S A All of these are known quantities obtained from the factory calibration of the gravimeter; S33. Define horizontal accelerometer A before rotation. x A y and gravity sensor A z The output acceleration vector is A1 = [A 1x A 1y A 1z After rotation, horizontal accelerometer A x A y and gravity sensor A z The output acceleration vector is A2 = [A 2x A 2y A 2z ], then A1 = K A S A (E1-B A A2 = K A S A (E2-B A ); S34. The local gravitational acceleration is g, and the corresponding angle changes of the platform's outer frame before and after rotation are dA. Q The corresponding angle changes of the inner frame of the platform before and after rotation are dA. P Then we can obtain: The inconsistency errors between the inertial component coordinate system and the mechanical table coordinate system were obtained by measuring the angular changes of the outer and inner frames of the platform before and after rotation: dA Q dA P The unit is arcsecond, dG x dG represents the inconsistency angle between the z-axis of the inertial component coordinate system and the y-axis of the mechanical table coordinate system. y The angle representing the inconsistency error between the z-axis of the inertial component coordinate system and the x-axis of the mechanical table coordinate system.

7. The method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter according to claim 6, characterized in that, The method for step S4 is as follows: S41. Define the gyroscope G x G y G z The installation error matrix between the input axis coordinate system of the gyroscope assembly and the coordinate system of the inertial assembly is S. G S G S is the known quantity obtained from the factory calibration of the gravimeter. G The expression is: Where S Gxy S is the inconsistency angle between the y-axis of the gyroscope component's input axis coordinate system and the x-axis of the inertial component's coordinate system. Gxz S is the inconsistency angle between the z-axis of the gyroscope component's input axis coordinate system and the x-axis of the inertial component's coordinate system. Gyz The inconsistency error angle between the z-axis of the input axis coordinate system of the gyroscope component and the y-axis of the inertial component coordinate system; S42.Use dG x dG y For S G Compensation is performed to obtain the new installation error matrix S between the gyroscope component input axis coordinate system and the inertial component coordinate system after compensation. G ′, S G The expression is:

8. The method for establishing a high-precision measurement benchmark for an unmanned platform gravimeter according to claim 1, characterized in that, In step S5, maintain the fine alignment time for 20 minutes.

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