A local gravity disturbance compensation method and system based on variable volume three-dimensional integration and deformation coupling

Abstract

The application provides a local gravity disturbance compensation method and system based on variable volume three-dimensional integration and deformation coupling, relates to the technical field of quantum precision measurement and gravity navigation, and acquires real-time geometric and mass parameters of a local dynamic mass source and synchronously collects three-dimensional attitude angle information of a carrier; a dynamic coordinate transformation model containing a carrier attitude matrix is constructed, a direct gravity disturbance quantity is calculated based on variable volume three-dimensional integration, a hysteresis deformation displacement of the carrier structure is acquired, a space gravity gradient coupling error is acquired, the direct gravity disturbance quantity and the gradient coupling gravity error are superposed to acquire a total local gravity disturbance quantity, the total local gravity disturbance quantity is subjected to time domain convolution with a quantum sensitivity function of a cold atom interferometer, and the local gravity disturbance compensation is completed by deducting the total local gravity disturbance quantity in an interference phase solving link. The application solves the problems of low gravity measurement compensation precision caused by near-field failure of a mass point model, neglect of three-dimensional attitude coupling and neglect of deformation gradient polarity reversal in the prior art.

Description

Technical Field

[0001] This invention relates to the field of quantum precision measurement and gravity navigation technology, specifically to a method and system for compensating for local gravitational disturbances based on variable volume three-dimensional integration and deformation coupling. Background Technology

[0002] The Cold Atom Interferometry Gravimeter (CAIG) is an absolute gravity measurement instrument based on the principle of matter wave interference. Its core mechanism utilizes stimulated Raman transitions to coherently manipulate freely falling cold atom clusters in a vacuum. By extracting the phase information of the interference fringes of the atomic matter waves, it achieves high-precision absolute measurement of gravitational acceleration. After completing high-frequency vibration compensation and correction for non-inertial frame motion errors, the theoretical measurement accuracy of the cold atom gravimeter has approached that of the microgalvanic plane. Even Naga ( nGal The magnitude is on the order of 10^-10^-1. At this extremely high sensitivity, the gravitational field fluctuations (i.e., Newtonian noise) caused by minute changes in the mass distribution of the environment surrounding the carrier have become the core physical bottleneck restricting the accuracy of absolute gravity measurements.

[0003] In recent years, with the engineering of high-precision portable cold atom gravimeters, these instruments have gradually moved out of the laboratory and into complex and dynamic environments such as submarines, ships, vehicles, and aircraft. For example, Qi Kun et al. from Huazhong University of Science and Technology pointed out in their paper "Experimental Study on Vibration-Related Effects in Atomic Interferometric Gravity Measurement" that environmental coupling effects are the key limiting factor for gravimeter accuracy. In practical engineering applications, large-scale dynamic transfers of mass are unavoidable within the carrier. For instance, during depth adjustments in submarines, ballast tanks undergo hundreds of tons of water injection and dewatering; aircraft consume large amounts of fuel during long-duration flights; and research vessels relocate large equipment during operations. This localized dynamic transfer of mass alters the mass distribution around the gravimeter, resulting in minute gravitational field fluctuations. At the extremely high sensitivity of cold atom gravimeters, such localized gravitational interference can cause severe step-like system drift in the measurement results, rendering the gravity measurement ineffective within a short period.

[0004] Previous literature on the measurement and compensation of local mass gravitational disturbances typically employs a simplified "point-mass model" for estimation, treating the disturbance source as an equivalent point mass with concentrated mass and using Newton's law of universal gravitation for simple calculations. However, this method suffers from three significant drawbacks in practical high-precision dynamic measurements: First, the particle model suffers from severe nonlinear truncation errors under near-field conditions. In dynamic applications, interference sources (such as ballast tanks) are often located in regions extremely close to the gravimeter probe (near-field range, typically less than 5 meters). Under near-field conditions, fluid mass transfer manifests not only as a change in total mass but also as a dramatic nonlinear evolution of fluid volume, liquid level, and the spatial coordinates of the center of mass over time. The particle model cannot accurately describe the nonlinear gravitational field gradient generated by this variable-volume fluid, resulting in extremely low compensation accuracy.

[0005] Second, existing technologies neglect the coupling modulation of the carrier's three-dimensional dynamic attitude on the spatial projection of the gravitational field. In marine or aerial environments, carriers inevitably experience three-dimensional attitude changes such as roll, pitch, and yaw. This means that the spatial coordinates of the interference source relative to the gravimeter's sensitive axis are rotating in real time. Traditional static gravity models completely fail on dynamic carriers, making it impossible to achieve accurate projection of gravitational interference onto the gravimeter's sensitive axis.

[0006] Third, existing technologies suffer from a serious technical bias: they neglect the deep physical coupling mechanism of "mass transfer-viscoelastic deformation-gravitational gradient." Current methods often calculate the direct gravitational attraction of the mass in isolation, ignoring the minute elastic deformation caused to the load-bearing structure by a massive mass transfer. According to elasticity theory, large mass loads can cause micrometer-level sinking of the load-bearing structure. Because the Earth has approximately... The free-space gravity gradient causes the gravimeter probe to shift within the Earth's gravity gradient field as the structure sinks slightly, introducing non-negligible spurious gravity fluctuations. Further complicating matters, real metal ship hulls are not ideal elastic bodies; their deformation exhibits viscoelastic retardation. The coupling error between direct gravitational attraction and deformation gradient is often physically opposite (e.g., water filling the upper tank creates an upward gravitational pull, reducing gravity, but the pressure causing the probe to sink closer to the Earth's center increases gravity). Ignoring this polarity-reversing competitive mechanism and only compensating for direct gravity not only fails to eliminate the error but can even lead to the malignant consequence of "the more you compensate, the greater the error." Summary of the Invention

[0007] To address the problems of local mass transfer in complex dynamic environments exhibiting variable volume nonlinear evolution, being coupled and modulated by the three-dimensional attitude of the carrier, and relying on a single gravity model leading to decreased compensation accuracy, or even compensation failure due to neglecting deformation polarity reversal, this invention proposes a local gravity interference compensation method based on variable volume three-dimensional integral and deformation coupling.

[0008] This invention is achieved through the following technical solution: A method for compensating for local gravitational disturbances based on variable volume three-dimensional integral and deformation coupling includes the following steps: Step 1: Obtain the real-time geometric and mass parameters of the local dynamic mass source, and simultaneously acquire the three-dimensional attitude angle information of the carrier; Step 2: Construct a dynamic coordinate transformation model that includes the carrier attitude matrix, and calculate the direct gravitational disturbance based on variable volume three-dimensional integral. Step 3: Based on the Kelvin-Voigt viscoelastic theory and the spatial Green's function, obtain the hysteretic deformation displacement of the carrier structure; Step 4: Perform gravity gradient coupling calculation on the hysteresis deformation displacement to obtain the space gravity gradient coupling error; Step 5: The total local gravitational interference is obtained by superimposing the direct gravitational interference with the gradient coupling gravity error, and then convolved in the time domain with the quantum sensitivity function of the cold atom interferometer. This is then subtracted in the interferometric phase solution link to complete the local gravitational interference compensation.

[0009] Furthermore, in step one, The geometric center of the rectangular fluid container is set as the origin of the local coordinate system, and the total length and total width of the rectangular fluid container are determined. The instantaneous liquid level height of the variable volume rectangular fluid container can be obtained by directly measuring the liquid level using a liquid level sensor, or by collecting the cumulative value of the volumetric flow rate of the injected fluid using a flow meter and combining it with the bottom area of ​​the rectangular fluid container. Simultaneously, the actual density value of the fluid is obtained by using a temperature sensor for calibration, and the roll angle, pitch angle and heading angle of the carrier in the navigation coordinate system are collected in real time by a strapdown inertial navigation system installed on the carrier.

[0010] Furthermore, in step two, Based on the roll angle, pitch angle and heading angle of the carrier obtained in step one, construct a dynamic direction cosine matrix from the carrier coordinate system to the navigation coordinate system; Based on the predetermined total length and width of the rectangular fluid container, and combined with the instantaneous liquid level height obtained in step one, determine the set of integral boundary vertex coordinates of the fluid in the container at the current moment in the carrier coordinate system; The set of coordinates of the integral boundary vertices is rotated and transformed by a dynamic direction cosine matrix and mapped to the navigation coordinate system to obtain the coordinates of each vertex in the navigation coordinate system after transformation, and the dynamic spatial distance corresponding to each vertex is calculated. Using the extended Nagy analytical integral formula, based on the gravitational constant, the current fluid density obtained in step one, and the coordinates of each vertex and the dynamic spatial distance in the transformed navigation coordinate system, the direct gravitational disturbance generated by the variable volume fluid at the sensitive center of the gravimeter probe is calculated.

[0011] Furthermore, in step three, Based on the current fluid density, instantaneous liquid level height, and gravitational constant obtained in step one, determine the dynamic load on the fluid surface; The viscoelastic hysteresis effect of the carrier metal structure is considered in the calculation. Based on the predetermined Poisson's ratio of the load-bearing structure, Young's modulus, bottom area of ​​the fluid container, and viscoelastic hysteresis time constant of the carrier metal structure, the hysteresis deformation displacement of the carrier structure is obtained by combining the dynamic load on the fluid surface.

[0012] Furthermore, in step four, The gravity gradient coupling calculation specifically involves multiplying the predetermined local free space gravity gradient value with the hysteresis deformation displacement obtained in step three to calculate the corresponding spatial gravity gradient coupling error.

[0013] Furthermore, in step five, The total local gravitational disturbance is obtained by combining the direct gravitational disturbance obtained in step two with the spatial gravity gradient coupling error obtained in step four. The total local gravitational disturbance is convolved with the quantum sensitivity function of the cold atom interferometer in the time domain to obtain the compensation phase of the interference fringes; An augmented state-space model is constructed, and based on fringe offset and interference fringe contrast, combined with the gravity phase of the pure Earth background to be extracted, the residual vibration phase after processing by the vibration isolation system, the compensation phase, and measurement noise, a nonlinear observation equation is constructed. By solving the nonlinear observation equations through nonlinear fitting or Bayesian inference, the pure Earth background gravity phase is obtained, thereby acquiring accurate absolute gravity information.

[0014] A local gravitational disturbance compensation system based on variable volume three-dimensional integral and deformation coupling; The system includes a parameter acquisition module, a direct gravity calculation module, a deformation displacement acquisition module, a gradient coupling calculation module, and a comprehensive compensation module; The parameter acquisition module is used to acquire the real-time geometric and mass parameters of the local dynamic mass source and simultaneously collect the three-dimensional attitude angle information of the carrier. The direct gravity calculation module is used to construct a dynamic coordinate transformation model and calculate the direct gravity disturbance based on the variable volume three-dimensional integral. The deformation displacement acquisition module is used to acquire the hysteretic deformation displacement of the carrier structure based on the Kelvin-Voigt viscoelastic theory. The gradient coupling calculation module is used to calculate the spatial gravity gradient coupling error; The integrated compensation module is used to superimpose the direct gravitational interference amount with the gradient coupling gravity error to obtain the total local gravitational interference amount, and then perform time-domain convolution with the quantum sensitivity function of the cold atom interferometer, and deduct it in the interferometric phase solution link.

[0015] A computer device system includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above-described method. A computer-readable storage medium having a computer program / instructions stored thereon, which, when executed by a processor, implement the steps of the above-described method.

[0016] A computer program product includes a computer program / instructions that, when executed by a processor, implement the steps of the method described above.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention overcomes the near-field failure limitation of traditional point mass models. By constructing a variable-volume three-dimensional integral analytical model that includes the three-dimensional attitude matrix of the carrier, it accurately describes the nonlinear gravitational field distribution generated by the evolution of fluid surface height under dynamic oscillation conditions. The logarithmic term in the formula represents the two-dimensional mass distribution contribution of the sidewalls, and the arctangent term represents the three-dimensional solid angle contribution of the apex, improving the evaluation accuracy of near-field gravitational disturbances from the milligaussian level to the microgaussian level.

[0018] 2. This invention achieves, for the first time, coupled compensation between deformation and gravitational gradient, overcoming the biases of existing technologies. It innovatively introduces Kelvin-Voigt viscoelasticity theory and spatial Green's function, revealing the deep physical coupling mechanism of "mass transfer - viscoelastic hysteresis sinking - spatial gravitational gradient." It solves the problem of compensation failure caused by the opposite physical polarity of direct gravitational attraction and gradient coupling errors, achieving deep decoupling of errors.

[0019] 3. This invention achieves a precise mapping between underlying quantum effects and macroscopic gravitational disturbances. By performing a time-domain convolution between the analytically calculated total disturbance and the quantum sensitivity function of the cold atom interferometer, the problem of the non-static evolution of gravitational disturbances during atom fall is solved. This method has low computational cost and can be perfectly embedded into the high-frequency data processing link of the cold atom gravimeter, enabling high-precision real-time compensation of the cold atom gravimeter under complex dynamic environments (such as the injection and drainage of ballast tanks in submarines and ship swaying). Attached Figure Description

[0020] Figure 1 This is a block diagram of the local gravitational interference compensation system of the present invention; Figure 2 This is a local dynamic mass source liquid level evolution curve provided in an embodiment of the present invention; Figure 3 This is a diagram illustrating the coupling competition mechanism between variable volume gravity and deformation gradient provided in an embodiment of the present invention. Figure 4 This is a comparison diagram of gravity measurements before and after local gravitational interference compensation provided in an embodiment of the present invention; Figure 5 The phase shift pattern of atomic interference fringes caused by local gravitational interference is provided in an embodiment of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials, reagents, methods, and instruments used are all conventional materials, reagents, methods, and instruments in the art, and can be obtained commercially by those skilled in the art.

[0023] To address the problems of near-field failure of particle models, neglect of three-dimensional attitude coupling, and low accuracy of gravity measurement compensation caused by neglect of deformation gradient polarity reversal in existing technologies, this invention proposes a local gravitational disturbance compensation method based on variable volume three-dimensional integration and deformation coupling, comprising the following steps: Step 1: Acquire the real-time geometric and mass parameters of the local dynamic mass source, and simultaneously collect the three-dimensional attitude angle information of the carrier to complete system initialization; Step 2: Construct a dynamic coordinate transformation model that includes the carrier attitude matrix, and calculate the direct gravitational disturbance based on variable volume three-dimensional integral. Step 3: Based on the Kelvin-Voigt viscoelastic theory and the spatial Green's function, obtain the hysteretic deformation displacement of the carrier structure; Step 4: Perform gravity gradient coupling calculation on the hysteresis deformation displacement to obtain the space gravity gradient coupling error; Step 5: The total local gravitational interference is obtained by superimposing the direct gravitational disturbance quantity with the gradient coupling gravity error, and then convolved in the time domain with the quantum sensitivity function of the cold atom interferometer, and subtracted in the interferometric phase solution link.

[0024] In step one, the real-time geometric and mass parameters of the local dynamic mass source are acquired, and the three-dimensional attitude angle information of the carrier is collected simultaneously to complete the system initialization. The specific method is as follows: The instantaneous liquid level height h(t) of a variable-volume fluid container is obtained using a level sensor or flow meter. To simplify the subsequent three-dimensional integration boundary, the geometric center of the rectangular fluid container is set as the local coordinate origin, with a total length of 2a and a total width of 2b. The formula for obtaining the instantaneous liquid level height is:

[0025] in, Q ( τ This indicates the volumetric flow rate of the injected fluid. Simultaneously, the current fluid density is obtained using a temperature sensor for calibration. ; and the roll angle of the carrier in the navigation coordinate system is obtained in real time through the strapdown inertial navigation system on the carrier. Pitch angle and heading angle .

[0026] In step two, a dynamic coordinate transformation model including the carrier attitude matrix is ​​constructed, and the direct gravitational disturbance is calculated based on the variable volume three-dimensional integral. The specific method is as follows: First, construct the dynamic direction cosine matrix from the carrier coordinate system (b-frame) to the navigation coordinate system (n-frame). :

[0027] The vertex coordinate parameter matrix of the fluid integral boundary The dynamic spatial distance is obtained by mapping the attitude matrix to the navigation coordinate system. The calculation formula is as follows:

[0028] Subsequently, using the extended Nagy analytical integral formula, the direct gravitational disturbance generated by the variable volume fluid at the sensitive center of the gravimeter probe was calculated. :

[0029] in, It is the gravitational constant; , , For the process The dynamic integral boundary parameters after rotational transformation correspond to the dynamic projected boundaries of the fluid container along the X, Y, and Z axes, respectively. The logarithmic term in this formula represents the two-dimensional mass distribution contribution of the sidewalls, while the arctangent term represents the three-dimensional solid angle contribution of the apex.

[0030] In step three, based on the Kelvin-Voigt viscoelastic theory and the spatial Green's function, the hysteretic deformation displacement of the carrier structure is obtained. The specific method is as follows: Considering that the metal hull structure is not an ideal elastic body, its deformation exhibits a viscoelastic hysteresis effect, and the hysteresis deformation displacement... The formula for obtaining it is:

[0031] in, Poisson's ratio for load-bearing structures. For Young's modulus, Let be the integral domain of the bottom area of ​​the fluid container; For dynamic loads on the fluid surface, It is the gravitational constant; Let be the viscoelastic hysteresis time constant of the carrier metal structure, and the integral term be... It characterizes the hysteresis effect of deformation evolution over time.

[0032] In step four, the hysteresis deformation displacement is... Perform gravity gradient coupling calculations to obtain the space gravity gradient coupling error. The specific method is as follows:

[0033] in, This represents the local free-space gravity gradient, typically taken as a value of [value missing]. This step precisely converts structural deformation displacement into gravity measurement error.

[0034] In step five, the total local gravitational disturbance is obtained by superimposing the direct gravitational disturbance with the gradient-coupled gravity error. Then, it is convolved in the time domain with the quantum sensitivity function of the cold atom interferometer, and subtracted in the interferometric phase solution link. The specific method is as follows: First, obtain the total local gravitational disturbance. Due to interference during atomic fall... The time interval is dynamically changing, so a quantum sensitivity function is introduced. Calculate the compensated phase of the interference fringes :

[0035] in, For effective wave vector, This is the piecewise sensitivity function for the Raman pulse sequence of a cold atom interferometer. Subsequently, an augmented state-space model is constructed, and the nonlinear observation equations are... The method for obtaining it is as follows:

[0036] in, For stripe offset, For the contrast of interference fringes, The pure Earth background gravity phase to be extracted. The residual vibration phase after treatment by the vibration isolation system. To measure noise, the solution is obtained through nonlinear fitting or Bayesian inference algorithms. This allows us to obtain accurate absolute gravity information.

[0037] Example 1: like Figure 1 As shown, this embodiment of the invention provides a local gravitational disturbance compensation method based on variable volume three-dimensional integral and deformation coupling. To verify the effectiveness of the invention, the method is tested and verified using the MATLAB simulation platform.

[0038] First, the local gravity gradient, fluid density, and other parameters are loaded into the program to complete parameter initialization. The cold atom gravimeter probe is set to be located at the origin of the coordinate system, with an equivalent water tank above it (half length 1.5m, half width 1.5m, bottom Z coordinate -0.5m).

[0039] Simultaneously obtain the instantaneous liquid level height h(t) in the water tank, such as Figure 2 As shown, the water filling process of the water tank was simulated. During the 0-600s period, the system was in the baseline test phase with the liquid level at 0; from 600s to 2400s, the water pump filled water at a constant flow rate, and the liquid level height h(t) increased linearly to 2.0m; after 2400s, it remained at full load.

[0040] Next, obtain the direct gravitational disturbance quantity. The calculation formula is:

[0041] And obtain the elastic deformation displacement including the hysteresis effect. :

[0042] Finally, the spatial gravity gradient coupling error is constructed based on the elastic deformation displacement. The specific formula for obtaining it is:

[0043] After completing the above steps, the direct gravitational disturbance is superimposed with the gradient-coupled gravity error to obtain the total local gravitational disturbance. .

[0044] like Figure 3As shown, this invention profoundly reveals the complex error competition mechanism caused by local mass transfer. As the liquid level rises, the mass of the water increases. Since the water tank is located above the probe, the water exerts a direct upward gravitational pull on the gravimeter probe. This upward pull partially offsets Earth's gravity, resulting in a decrease in the gravity value measured by the gravimeter. Therefore, direct gravitational interference... This manifests as a negative increase (as shown by the blue dashed line in the figure). Simultaneously, the total gravity of the water compresses the flexible base, causing elastic sinking, and the probe displaces downwards (closer to the Earth's center) within the Earth's gravity gradient field. Based on the characteristics of the free-space gravity gradient, probe sinking leads to an increase in the measured gravity value; therefore, the deformation gradient coupling error increases. This exhibits a positive growth (as shown by the red dotted line in the figure). This invention superimposes the two to obtain the total local gravitational disturbance. (As shown by the black solid line in the figure), deep physical decoupling of errors is achieved.

[0045] Next, the total local gravitational disturbance is convolved with the quantum sensitivity function and then substituted into the nonlinear observation equation for phase compensation. The specific formula is as follows:

[0046] like Figure 4 The diagram illustrates the final effect of the compensation algorithm of this invention. Without compensation (red curve), the gravimeter's measurements exhibited a significant step-like system drift (disruption due to interference) as the water injection process progressed, severely compromising the accuracy of absolute gravity measurements. After introducing the proposed "variable volume three-dimensional integral and deformation coupling" compensation model (blue curve), the reconstructed gravity measurements returned to stability (restoring the baseline), and the root mean square error (RMSE) of the residuals was suppressed within the instrument's background noise level, completely eliminating interference caused by local dynamic mass transfer.

[0047] like Figure 5 As shown, the effect of gravitational interference on cold atom interferometers is intuitively demonstrated from the perspective of underlying quantum mechanics. Local gravitational interference. This causes additional phase accumulation in the atomic matter waves under Raman laser irradiation, resulting in a lateral phase shift in the final interference fringes (red dashed lines) relative to the ideal fringes (black solid lines). This invention addresses this by injecting a compensating phase forward into the interference phase calculation link, which can pull the shifted fringes back to the ideal position in real time.

[0048] Example 2: This invention also proposes a local gravitational disturbance compensation system based on variable volume three-dimensional integral and deformation coupling: The system includes a parameter acquisition module, a direct gravity calculation module, a deformation displacement acquisition module, a gradient coupling calculation module, and a comprehensive compensation module. The parameter acquisition module is used to acquire the real-time geometric and mass parameters of the local dynamic mass source and simultaneously collect the three-dimensional attitude angle information of the carrier. The direct gravity calculation module is used to construct a dynamic coordinate transformation model and calculate the direct gravity disturbance based on the variable volume three-dimensional integral. The deformation displacement acquisition module is used to acquire the hysteretic deformation displacement of the carrier structure based on the Kelvin-Voigt viscoelastic theory. The gradient coupling calculation module is used to calculate the spatial gravity gradient coupling error; The integrated compensation module is used to superimpose the direct gravitational interference amount with the gradient coupling gravity error to obtain the total local gravitational interference amount, and then perform time-domain convolution with the quantum sensitivity function of the cold atom interferometer, and deduct it in the interferometric phase solution link.

[0049] A computer device system includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above-described method. A computer-readable storage medium having a computer program / instructions stored thereon, which, when executed by a processor, implement the steps of the above-described method.

[0050] A computer program product includes a computer program / instructions that, when executed by a processor, implement the steps of the method described above.

[0051] The memory in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. Non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate synchronous DRAM (DDRSDRAM), enhanced synchronous DRAM (ESDRAM), synchronous linked DRAM (SLDRAM), and direct rambus RAM (DRRAM). It should be noted that the memory of the methods described in this invention is intended to include, but is not limited to, these and any other suitable types of memory.

[0052] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired means such as coaxial cable, optical fiber, digital subscriber line (DSL), or wireless means such as infrared, wireless, or microwave. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available media can be magnetic media such as floppy disks, hard disks, magnetic tapes, optical media such as high-density digital video discs (DVDs), or semiconductor media such as solid-state drives (SSDs).

[0053] In implementation, each step of the above method can be completed by integrated logic circuits in the processor's hardware or by instructions in software. The steps of the method disclosed in the embodiments of this application can be directly implemented by a hardware processor, or by a combination of hardware and software modules in the processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory, and the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, detailed descriptions are omitted here.

[0054] It should be noted that the processor in the embodiments of this application can be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method embodiments can be completed by the integrated logic circuits in the processor's hardware or by instructions in software form. The processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied as execution by a hardware decoding processor, or as execution by a combination of hardware and software modules in the decoding processor. The software modules can be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above methods.

[0055] The above provides a detailed description of the local gravitational disturbance compensation method and system based on variable volume three-dimensional integral and deformation coupling proposed in this invention. The principles and implementation methods of this invention have been explained. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A method for compensating for local gravitational disturbances based on variable volume three-dimensional integral and deformation coupling, characterized in that, Includes the following steps: Step 1: Obtain the real-time geometric and mass parameters of the local dynamic mass source, and simultaneously acquire the three-dimensional attitude angle information of the carrier; Step 2: Construct a dynamic coordinate transformation model that includes the carrier attitude matrix, and calculate the direct gravitational disturbance based on variable volume three-dimensional integral. Step 3: Based on the Kelvin-Voigt viscoelastic theory and the spatial Green's function, obtain the hysteretic deformation displacement of the carrier structure; Step 4: Perform gravity gradient coupling calculation on the hysteresis deformation displacement to obtain the space gravity gradient coupling error; Step 5: The total local gravitational interference is obtained by superimposing the direct gravitational interference with the gradient coupling gravity error, and then convolved in the time domain with the quantum sensitivity function of the cold atom interferometer. This is then subtracted in the interferometric phase solution link to complete the local gravitational interference compensation.

2. The method according to claim 1, characterized in that: In step one, The geometric center of the rectangular fluid container is set as the origin of the local coordinate system, and the total length and total width of the rectangular fluid container are determined. The instantaneous liquid level height of the variable volume rectangular fluid container can be obtained by directly measuring the liquid level using a liquid level sensor, or by collecting the cumulative value of the volumetric flow rate of the injected fluid using a flow meter and combining it with the bottom area of ​​the rectangular fluid container. Simultaneously, the actual density value of the fluid is obtained by using a temperature sensor for calibration, and the roll angle, pitch angle and heading angle of the carrier in the navigation coordinate system are collected in real time by a strapdown inertial navigation system installed on the carrier.

3. The method according to claim 2, characterized in that: In step two, Based on the roll angle, pitch angle and heading angle of the carrier obtained in step one, construct a dynamic direction cosine matrix from the carrier coordinate system to the navigation coordinate system; Based on the predetermined total length and width of the rectangular fluid container, and combined with the instantaneous liquid level height obtained in step one, determine the set of integral boundary vertex coordinates of the fluid in the container at the current moment in the carrier coordinate system; The set of coordinates of the integral boundary vertices is rotated and transformed by a dynamic direction cosine matrix and mapped to the navigation coordinate system to obtain the coordinates of each vertex in the navigation coordinate system after transformation, and the dynamic spatial distance corresponding to each vertex is calculated. Using the extended Nagy analytical integral formula, based on the gravitational constant, the current fluid density obtained in step one, and the coordinates of each vertex and the dynamic spatial distance in the transformed navigation coordinate system, the direct gravitational disturbance generated by the variable volume fluid at the sensitive center of the gravimeter probe is calculated.

4. The method according to claim 3, characterized in that: In step three, Based on the current fluid density, instantaneous liquid level height, and gravitational constant obtained in step one, determine the dynamic load on the fluid surface; The viscoelastic hysteresis effect of the carrier metal structure is considered in the calculation. Based on the predetermined Poisson's ratio of the load-bearing structure, Young's modulus, bottom area of ​​the fluid container, and viscoelastic hysteresis time constant of the carrier metal structure, the hysteresis deformation displacement of the carrier structure is obtained by combining the dynamic load on the fluid surface.

5. The method according to claim 4, characterized in that: In step four, The gravity gradient coupling calculation specifically involves multiplying the predetermined local free space gravity gradient value with the hysteresis deformation displacement obtained in step three to calculate the corresponding spatial gravity gradient coupling error.

6. The method according to claim 5, characterized in that: In step five, The total local gravitational disturbance is obtained by combining the direct gravitational disturbance obtained in step two with the spatial gravity gradient coupling error obtained in step four. The total local gravitational disturbance is convolved with the quantum sensitivity function of the cold atom interferometer in the time domain to obtain the compensation phase of the interference fringes; An augmented state-space model is constructed, and based on fringe offset and interference fringe contrast, combined with the gravity phase of the pure Earth background to be extracted, the residual vibration phase after processing by the vibration isolation system, the compensation phase, and measurement noise, a nonlinear observation equation is constructed. By solving the nonlinear observation equations through nonlinear fitting or Bayesian inference, the pure Earth background gravity phase is obtained, thereby acquiring accurate absolute gravity information.

7. A local gravitational disturbance compensation system based on variable volume three-dimensional integral and deformation coupling, characterized in that: The system is used to execute the local gravitational disturbance compensation method based on variable volume three-dimensional integral and deformation coupling as described in any one of claims 1 to 6; The system includes a parameter acquisition module, a direct gravity calculation module, a deformation displacement acquisition module, a gradient coupling calculation module, and a comprehensive compensation module; The parameter acquisition module is used to acquire the real-time geometric and mass parameters of the local dynamic mass source and simultaneously collect the three-dimensional attitude angle information of the carrier. The direct gravity calculation module is used to construct a dynamic coordinate transformation model and calculate the direct gravity disturbance based on the variable volume three-dimensional integral. The deformation displacement acquisition module is used to acquire the hysteretic deformation displacement of the carrier structure based on the Kelvin-Voigt viscoelastic theory. The gradient coupling calculation module is used to calculate the spatial gravity gradient coupling error; The integrated compensation module is used to superimpose the direct gravitational interference amount with the gradient coupling gravity error to obtain the total local gravitational interference amount, and then perform time-domain convolution with the quantum sensitivity function of the cold atom interferometer, and deduct it in the interferometric phase solution link.

8. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When executed by a processor, the computer program implements the steps of the method according to any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that: When executed by a processor, the computer program implements the steps of the method according to any one of claims 1 to 6.

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