34 results about "Gravity gradient" patented technology

The present application relates to a kind of rotation accelerometer gravity gradiometer attitude error post-processing compensation method, comprising the following steps: step 1, original motion data is acquired using the inertial measurement unit fixed with gravity gradient sensor, and the positioning and speed information provided by radio navigation are combined to complete original data acquisition;Step 2, the attitude error of gravity gradient sensor in the measurement process is optimally estimated;Step 3, based on the coordinate transformation matrix of gravity gradient tensor under different coordinate systems, the error compensation of gravity gradient measurement value is carried out, and finally the gravity gradient measurement data after attitude error compensation is obtained.The present application can be used in dynamic measurement environment, and the measurement information of carrier motion is measured using gyroscope and accelerometer, the attitude error of gravity gradient measurement component is estimated and compensated offline with high precision, and then the dynamic measurement precision of rotation accelerometer gravity gradiometer is improved.

The invention belongs to the technical field of uranium ore geological exploration, and particularly relates to a sandstone uranium ore excretion structure authenticity discrimination method based on gravity gradient deep constraint, which comprises the following steps: step 1, deep fracture ridge extraction based on gravity data; 2, constructing a'deep part-earth surface 'structure projection buffer area; 3, removing a micro-landform catchment area based on a DEM (Digital Elevation Model); 4, extracting earth surface remote sensing abnormity; and step five, space coupling and excretion zone authenticity discrimination are carried out. According to the method, by constructing a deep fracture-earth surface projection buffer area model and combining with micro-landform analysis, earth surface non-structural ponding and salt accumulation interference is effectively eliminated, and an effective discharge zone with a deep root is accurately locked.

The invention relates to the technical field of oil and gas resource exploration data processing, in particular to a three-dimensional gravity gradient inversion method for oil and gas resource exploration, a medium and equipment. The method comprises the following steps: acquiring gravity gradient plane two-dimensional observation data of an exploration target area; setting an inversion constraint function; and performing inversion iterative operation to obtain an underground three-dimensional density structure, and delineating a space boundary of a salt hill, a rock cover or an oil storage structure according to the structure. According to the method, a regularization objective function is constructed based on the L1 norm of the model and the total variation TV1 of the model, an L1-TV1 weight factor is introduced and reasonably selected, and a density model vector after depth weighting is used in the total variation of the model. The method can effectively overcome the shielding effect of the shallow rock cover on the deep salt nucleus in salt hill detection, improve the depth resolution and the boundary depiction definition, reduce the inversion multiplicity of solutions, and provide accurate guidance for oil-gas exploration and drilling risk avoidance.

The application relates to a configuration design method of a three-dimensional orbiting sail with posture stability, and belongs to the field of spacecraft attitude dynamics and structure design.The application is realized by the following method: considering the environmental perturbation of atmospheric resistance, atmospheric resistance moment and gravity gradient moment, an orbit attitude coupling dynamics model of a three-dimensional orbiting sail system is established based on a position vector and Euler angles; the three-dimensional orbiting sail and a spacecraft body are regarded as rigid bodies, and the windward area is considered to be blocked by airflow so as to more accurately describe the orbit movement and attitude movement of the system in the orbiting process; the attitude movement is simplified for the attitude dynamics of the system; the attitude stability of the system in the orbiting process is analyzed by using a phase plane method, a Lyapunov energy function method and other stability analysis methods of nonlinear dynamics systems; the relationship between important structure parameters such as a cone angle and a support rod length of the three-dimensional orbiting sail and the attitude stability is further constructed; and the three-dimensional orbiting sail satisfying the preset attitude stability requirement is obtained based on the relationship, so that the configuration design is realized.

The invention belongs to the technical field of precision measurement, and relates to an indoor movable base testing device for a horizontal tensor gravity gradiometer and application of the indoor movable base testing device. The device comprises a control processing module, and a gravity gradient standard field generation module and a motion simulation module which are respectively connected with the control processing module, the motion simulation module and the gravity gradient standard field generation module are both fixed on a foundation, and the gravity gradient standard field generation module comprises an electric displacement table; a pair of attraction source assemblies arranged in an orthogonal mode is fixed to the electric displacement table. The horizontal tensor gravity gradiometer to be measured is arranged on the motion simulation module and located between the pair of gravitation source assemblies; the control processing module is used for driving the motion simulation module to simulate the environment of the movable base, and is also used for enabling the gravitation source assembly to translate on the electric displacement table and generating a gravity gradient standard field dynamically matched with the motion of the gravitation source assembly. According to the invention, the performance verification of the horizontal tensor gravity gradiometer under the condition of simulating the movable base can be realized, and the test cost and period are reduced.

The invention discloses a gravity gradient layering-overall inversion method based on a radial power spectrum, and relates to the technical field of gravity gradient inversion. The method comprises the following steps: acquiring gravity gradient data of a target area, and preprocessing the gravity gradient data; performing wavelet multi-scale decomposition on the preprocessed gravity gradient data to obtain wavelet detail signals of different orders; performing burial depth estimation on the wavelet detail signals of different orders to extract depth features of sources corresponding to the signals of each order; and performing layered-overall simulated annealing inversion based on the depth features of the source corresponding to each order of signal, and outputting an inversion result. According to the method, the radial power spectrum method can be applied to the gravity gradient signals, the problem of incomplete signal separation caused by wavelet multi-scale analysis is effectively solved, and the inversion accuracy is improved.

The invention discloses an edge detection filter based on a TANH function and an arcsine function, and the filter determines Bouguer gravity anomaly data through obtaining free air gravity anomaly data, terrain correction values and Bouguer correction values of a plurality of gravity points of a research region. Calculating Gaussian envelope gradient data based on the gravity gradient tensor component data and Gaussian envelope, and obtaining an edge detection filtering result according to the Gaussian envelope gradient data and TANH function filtering; noise interference can be effectively suppressed by adopting a double-constraint mechanism, a generated boundary result is clear and continuous, and the problems of boundary divergence, positioning fuzziness, form distortion and the like existing in a traditional method are effectively solved; anomalous bodies with different depths are synchronously and accurately identified, stable detection performance can be maintained under complex geological conditions, and generation of false boundaries under the condition of coexistence of positive and negative anomalies is reduced; the reliable boundary recognition capability can be kept under the strong noise background, manual intervention in the preprocessing link is reduced, and the practical application convenience and the result reliability are improved.

This invention provides a method, system, and medium for predicting earthquake source locations using TLF-GV signals, belonging to the field of earthquake prediction technology. The method includes: constructing a U-Net++ model, where multiple encoding blocks are used to sequentially generate feature maps of different spatial scales based on the gradient tensors extracted from TLF-GV; multiple decoding blocks are used to decode and output earthquake source probability heatmaps based on the feature maps at different spatial scales; obtaining active fault distribution maps, and constructing a geological prior penalty term based on the distance from each grid cell in the earthquake source probability heatmap to the nearest active fault, and constructing a loss function by combining the cross-entropy loss between the probability heatmap and the actual source mask; constructing a training set, using the concatenated features of the gradient tensors extracted from the gravity gradient grid and the fault binary mask as input to train and obtain the prediction model. This method utilizes the spatial grid features of the TLF-GV gravity gradient, combined with the small-scale feature capture capability of U-Net++, to effectively improve the accuracy of earthquake source location prediction.

This invention discloses a multi-source fusion monitoring method based on gravity gradient tensor and sedimentary evolution, belonging to the field of water conservancy engineering monitoring technology, including the following steps: Data acquisition: acquiring gravity / gravity gradient data, surface geometric deformation data, and spectral data. Spatial constraint: constructing a dynamic mask using geometric deformation data to constrain the spatial boundary of gravity inversion. Physical enhancement: performing gradient processing or fusion on gravity data to obtain high-resolution mass distribution. Density correction: calculating the dynamic density of sediments over time based on a sedimentary evolution model, and correcting the background fluid density based on spectral data. Coupled solution: substituting the above parameters into the coupling equation to solve for the volume or mass of sediments. This invention can achieve long-term, continuous, non-contact, and quantitative accurate monitoring of reservoir capacity changes and sediment deposition volume through the synergistic fusion of satellite gravity observation, airborne gravity gradient tensor observation, optical remote sensing, and sedimentary physical evolution models.

The application provides a CO2 storage monitoring method and system based on space-air-ground-well multi-source information. The application combines space-air-ground-well multi-source information, comprehensively interprets multi-source data obtained by synthetic aperture radar in space, air or semi-air transient electromagnetic in the sky, gravity gradient detection on the ground, and resistivity method and microseismic monitoring in the well. Reasonable use of different monitoring technologies plays a role of mutual assistance and mutual complementation, and then CO2 migration in the injection well and the stratum can be effectively monitored.

The invention discloses a multi-source submarine topography reconstruction method and system based on a frequency domain attention neural network, and relates to the technical field of submarine topography reconstruction. The method comprises the following steps: acquiring GEBCO water depth data, ocean gravity parameter abnormal data, vertical gravity gradient data, north component data of vertical deviation and east component data of vertical deviation, and constructing a five-channel input tensor; performing standardization processing on the five-channel input tensor, constructing a data set, and randomly dividing the data set into a training set and a test set through uniform sampling; processing the training set by using a frequency domain attention model to obtain fusion features, and inputting the fusion features into a predictor to generate a water depth estimated value; wherein the frequency domain attention model combines fast Fourier transform preprocessing with an attention mechanism, and the predictor is composed of a full connection layer and a ReLU activation function. According to the invention, the Fourier transform mechanism is introduced into the neural network architecture, the attention in the frequency domain is realized, and the submarine topography reconstruction precision is improved.

The invention provides a three-dimensional gravity gradient tensor inversion method with physical information constraints. Firstly, the coordinate system is established according to the gravity gradient tensor data and the underground space is divided, and the coordinates of the center point of the cube are extracted and normalized; then, a seven-layer fully connected neural network is constructed to output the network output parameters; an then the gravity gradient tensor data are calculated on the observation surface, the objective function is constructed by observation data and calculation data, including a data term and a regularization item; and finally, the objective function is automatically differentiated to update the network parameters and optimize the network output parameters until the maximum training times are reached. The invention overcomes challenges in existing methods, including over-reliance on initial parameters, over-simplification of the model and assumptions, insufficient ability to deal with nonlinear relationships, and poor generalization performance.

This invention provides a method for determining fault dip using gravity data. The method calculates the total horizontal gravity gradient based on the Bouguer gravity anomaly values ​​at various gravity measurement points above the fault and plots a total horizontal gravity gradient profile. A semi-extreme line segment is then drawn on the profile, and the direction of the vector from the maximum point to the midpoint of the semi-extreme line segment is taken as the fault dip. This method for determining fault dip using gravity data is a simple, fast, and intuitive research approach. It enables the rapid acquisition of fault dip information using an economical and efficient gravity exploration method, providing a reliable basis for studying fault-related geological structures.

The invention belongs to the technical field of airborne gravity measurement, and particularly relates to an airborne gravity gradient measurement data multi-source error modeling method, which comprises the following steps: constructing a transformation matrix of a measurement coordinate system and a carrier coordinate system; correcting the transformation matrix to obtain an error-containing transformation matrix; converting the gravity gradient tensor under the carrier coordinate system into a gravity gradient tensor under a measurement coordinate system by using the error-containing transformation matrix; converting the vibration error from a carrier coordinate system to a measurement coordinate system by using an error-containing transformation matrix; calculating a self-gradient error through mapping based on the mass distribution of each part of the airplane; describing random noise of a measurement system by adopting a Gaussian white noise model; and adding the gravity gradient tensor under the measurement coordinate system, the vibration error under the measurement coordinate system, the self-gradient error and the random noise of the measurement system to obtain a multi-source error model. Weak noise interference can be effectively detected, the approximation degree of an output result and actual measurement data is high, and the aviation gravity gradient measurement precision is greatly improved.

The invention provides a TLF-GV signal correlation seismic source position prediction method and system and a medium, and belongs to the technical field of seismic forecasting, and the method comprises the steps: constructing a U-Net + + model, and enabling a plurality of coding blocks to be used for generating feature maps of different spatial scales according to gradient tensors extracted by TLF-GV in sequence; the plurality of decoding blocks are used for decoding and outputting a seismic source probability thermodynamic diagram according to the feature maps of different spatial scales; obtaining an active fault distribution diagram, constructing a geological priori penalty term according to the distance from each grid unit in the seismic source probability thermodynamic diagram to the nearest active fault, and constructing a loss function in combination with cross entropy loss between the probability thermodynamic diagram and a real source mask; and constructing a training set, taking gradient tensor extracted by the gravity gradient grid and fault binary mask splicing features as input, and training to obtain a prediction model. According to the method, the spatial grid features of the TLF-GV gravity gradient are utilized, and the small-scale feature capture capability of U-Net + + is combined, so that the accuracy of seismic source position prediction is effectively improved.

The invention discloses an external coincidence precision evaluation method and equipment for a gravity gradient vertical horizontal component, and the method comprises the steps: enabling a shipborne cold atom absolute gravimeter and a full-tensor gravity gradiometer to be installed on the same ship, controlling a measurement ship to sail at a constant speed along a preset measurement line in the north-south direction or the east-west direction, and carrying out the synchronous measurement, obtaining gravity vertical component data output by a shipborne cold atom absolute gravimeter and vertical horizontal component data output by a full-tensor gravity gradiometer; performing filtering processing on the gravity vertical component data and the vertical horizontal component data, and performing point-by-point calculation on the filtered gravity vertical component data and the corresponding position data by adopting a midpoint difference method to obtain a calculation value of a vertical horizontal component; and respectively counting the total number of effective measuring points of the measuring lines in the north-south direction and the east-west direction, and calculating the root-mean-square error of the vertical horizontal component data and the corresponding calculation value, the root-mean-square error being the external coincidence precision of the vertical horizontal component of the full-tensor gravity gradiometer.

The invention discloses a multi-source fusion monitoring method based on gravity gradient tensor and sedimentary evolution, and relates to the technical field of hydraulic engineering monitoring, and the method comprises the following steps: data acquisition: obtaining gravity / gravity gradient data, surface geometric deformation data and spectral data; and spatial constraint: constructing a dynamic mask by using geometric deformation data, and constraining a spatial boundary of gravity inversion. And physical enhancement: carrying out gradient processing or fusion on the gravity data to obtain high-resolution mass distribution. And density correction: calculating the dynamic density of the sediment along with time based on the sedimentary evolution model, and correcting the background fluid density based on the spectral data. And coupling calculation: substituting the parameters into a coupling equation, and calculating the volume or mass of the sediment. According to the invention, long-term, continuous and non-contact quantitative accurate monitoring of reservoir capacity change and sediment deposition volume can be realized through collaborative fusion of satellite gravity observation, airborne gravity gradient tensor observation, optical remote sensing and a sedimentary physical evolution model.

The application provides a scissors deployable solar cell array system of a cubic satellite, which comprises a power supply box, a driving transmission device, a pressing release device, a connecting frame, a scissors deployable solar cell array, a deployment device and a locking device. The application is based on the principle of the scissors space deployable mechanism, adopts generalization and modularization design, has natural compactness, large face folding and unfolding ratio and high space utilization rate, has the modularization characteristic, is strong in expandability, can carry more solar cell panels in a unit volume, greatly improves the available power of the load, has strong functionality, and the special shape can provide the passive gravity gradient stabilization and high gain antenna integration advantages for the cubic satellite, the active driving deployment can customize the deployment time sequence, reduces the attitude influence on the cubic satellite in the deployment process, and is suitable for monitoring and communication task satellites and easy to complete orbit rapid deployment.

The invention discloses an edge detection filter based on a TANH function and an inclination angle, which determines Bouguer gravity anomaly data by obtaining gravity observation data and topographic data of each gravity point of a research area, calculates Gaussian envelope gravity gradient data according to the Bouguer gravity anomaly data, and obtains the edge detection filter based on the TANH function and the inclination angle. A corresponding filter is calculated based on a TANH function, an inclination angle algorithm and Gaussian envelope gravity gradient data, so that amplitude responses from different depth anomalous bodies can be effectively balanced, and edge signals generated by shallow and deep geologic bodies are more balanced in strength; the problem that amplitude distortion or concealment is easy to generate when a traditional method is used for processing multi-scale and multi-depth targets is solved; the geological boundary is clearly and accurately depicted under the complex geological condition, background noise interference is effectively suppressed, the recognition capability of edge details is remarkably enhanced, misjudgment caused by false edges and noise is effectively reduced, and the reliability of data interpretation and the accuracy of geological detection are improved.

A high-precision satellite attitude control method controlled by only a magnetic torque device, first, an expected control torque is calculated according to an attitude angle and an attitude angular velocity, then an expected control magnetic torque is calculated according to geomagnetic field information and the expected control torque, then an inertia angular velocity information is combined with a gravity gradient torque estimation and a previous period theory control torque estimation, a satellite residual magnetic torque is filtered and estimated by using a formula provided by the application, finally, the expected control magnetic torque is deducted from the estimated residual magnetic torque and converted into a magnetic torque device control voltage for output.

The present application relates to a kind of satellite angular momentum unloading method using rotating mechanism, belong to spacecraft attitude control technical field.The present application solves the technical problem that if satellite requires attitude on ground in on-orbit operation, existing method is not applicable.The method of the present application includes the following steps: calculating the change of rotational inertia caused by satellite rotating mechanism angle;Calculate the influence of satellite attitude and inertia matrix on gravity gradient torque;Use inertia product to unload angular momentum;And rotating mechanism angle planning.The satellite angular momentum unloading method using rotating mechanism of the present application, for satellite angular momentum unloading problem, using the characteristics of gravity gradient torque that can be generated by inertia product in satellite rotational inertia matrix.According to the current angular momentum of satellite, calculate the desired inertia product in satellite rotational inertia matrix.Further, the desired angle of rotating machine is calculated, so as to complete the unloading of angular momentum.

The invention relates to a space-based interference measurement system with a stable gravity gradient, and belongs to the field of space remote sensing. Satellites in the space-based interference measurement system are connected together through a tethered system, the tethered system is utilized to construct an interference baseline, the satellite keeps the baseline stable under the action of gravity gradient, the length of the tethered system is adjusted according to scene requirements, then the baseline of interference measurement is adjusted, and the interference measurement satellite performs interference measurement on a target. The stable position of the base line under the gravity gradient effect is a vertical scheme, the requirements of most interference measurement tasks can be met, and active control is not needed.

This invention discloses a method for monitoring the relative gravity of surface subsidence during coal mining. It involves deploying quantum gravity reference stations around the subsidence area, arranging relative gravimeters in a grid pattern within the basin, and arranging fiber optic gravity sensor chains in the underground roadway. Simultaneously, a UAV equipped with a cold atom gravity gradiometer performs periodic scans. Based on real-time data, a gravity field-mass migration model is established, correlating coal extraction volume, changes in rock density, and surface gravity anomalies. Wavelet multi-scale decomposition is used to eliminate geological background interference, and hydrological correction is applied, incorporating water level and porosity to optimize gravity variation values. When the corrected gravity variation exceeds a threshold, the azimuth of rock fracture is calculated using the gravity gradient tensor. Equivalent extraction thickness is derived based on gravity variation inversion, and the surface subsidence morphology is dynamically predicted using a subsidence basin model. A state vector is constructed by combining gravity, gradient, and deformation data, and multi-source fusion prediction is achieved through a filtering algorithm.

The invention discloses a method and equipment for measuring external coincidence precision of shipborne gravity gradient, and the method comprises the steps: enabling a shipborne cold atom absolute gravimeter and a shipborne gravity gradiometer to be installed on the same ship, carrying out the synchronous measurement according to a preset measurement network, obtaining a first gravity abnormal data grid outputted by the shipborne cold atom absolute gravimeter, and obtaining a first gravity abnormal data grid; the two different horizontal gravity gradient component data are output by a ship-borne gravity gradiometer; performing two-dimensional Fourier transform on the two different horizontal gravity gradient component data to obtain a gravity potential frequency spectrum, calculating a frequency spectrum of gravitational acceleration through the gravity potential frequency spectrum, and performing inverse Fourier transform on the frequency spectrum of the gravitational acceleration to obtain a second gravity anomaly data grid; carrying out difference operation on the first gravity anomaly data grid and the second gravity anomaly data grid point by point to obtain a difference grid, carrying out sample standard deviation statistics on the difference grid, and verifying whether the distribution of the difference grid accords with normal distribution or not; if the normal distribution is met, the standard deviation is the external conformance precision of the ship-borne gravity gradiometer.

The application relates to a method for improving underwater obstacle detection precision based on support vector regression gravity gradient. The underwater gravity gradient detection technology is beneficial to the safety of the navigation process of a submarine. In order to improve the underwater obstacle detection precision based on the gravity gradient detection technology, the application obtains a gravity gradient difference ratio (GGDR) equation related to only the position of an obstacle by using a difference method and a ratio method on the basis of a gravity gradient calculation formula, proposes a new support vector regression-gravity gradient joint method (SGJM), and verifies the reliability of the new SGJM in detecting underwater obstacles. Experimental results show that the positioning precision in the x and z directions in the obstacle position calculation based on the new SGJM is improved by 88% and 85% respectively. The new SGJM provides a theoretical and method reference for detecting underwater obstacles based on the gravity gradient in the future.

The application discloses a geological body boundary identification method and system based on aviation gravity gradient data, relates to the field of aviation geophysical exploration, and comprises the following steps: collecting original time sequence data and preprocessing the original time sequence data to obtain gridded gravity gradient tensor data; constructing a parameterized initial model of a three-dimensional geological structure based on the gridded gravity gradient tensor data; mapping the parameterized initial model into a theoretical gravity gradient response through a differentiable forward calculation graph; taking the matching degree of the theoretical gravity gradient response and the gridded gravity gradient tensor data as an objective, jointly optimizing voxel parameters and level set function parameters; and adopting a Hamilton Monte Carlo sampling method to sample the posterior probability distribution of the optimized voxel parameters and level set function parameters in the physical constraint probability optimization framework. The application solves the problem that a traditional deterministic method cannot quantize boundary confidence.

The invention discloses an astronomical coordinate determination method and system fusing laser tracking and gravity gradient correction, and relates to the technical field of astronomical coordinate determination. According to the method, a trajectory observation equation is established by dynamically tracking a target doing parabolic motion. And solving the trajectory observation equation by adopting a least square iteration method in which a damping factor is introduced to obtain a gravity vector in a local terrestrial coordinate system (LTCS). And then the gravity vectors are converted into a ground Cartesian coordinate system by using a direction conversion method based on a common baseline. The geodetic coordinates of the measurement point are used to determine an astronomical geodetic plumb deviation (DOV), and finally the astronomical coordinates of the measurement point are derived from the DOV component. According to the invention, continuous real-time coordinate determination without being influenced by weather is realized, and the key limitation of the traditional astronomical technology is overcome.

The invention is suitable for the technical field of geophysical exploration data processing, and provides an equivalent source denoising method based on shaping regularization, and the method comprises the steps: obtaining multi-component data; constructing an equivalent source forward modeling model; balancing the contribution of each component through robust scale normalization; introducing the zero trace relation as a physical soft constraint into an inversion system; a shaping regularization stable solving process is adopted, and regularization parameters are adaptively determined through an HKB method; and finally, obtaining a denoising result through forward modeling. According to the method, integrated denoising of multi-component data is realized, the component consistency, physical rationality and processing efficiency of a denoising result are remarkably improved, and the method is suitable for fine processing of aviation and ground gravity gradient measurement data.

The application belongs to the technical field of aviation gravity measurement, and particularly relates to a multi-source error modeling method for aviation gravity gradient measurement data, which comprises the following steps: constructing a transformation matrix of a measurement coordinate system and a carrier coordinate system; correcting the transformation matrix to obtain an error-containing transformation matrix; converting a gravity gradient tensor in the carrier coordinate system into a gravity gradient tensor in the measurement coordinate system by using the error-containing transformation matrix; converting vibration error from the carrier coordinate system to the measurement coordinate system by using the error-containing transformation matrix; calculating self-gradient error by mapping based on the mass distribution of each part of the airplane; describing measurement system random noise by using a Gaussian white noise model; and adding the gravity gradient tensor in the measurement coordinate system, the vibration error in the measurement coordinate system, the self-gradient error and the measurement system random noise to obtain a multi-source error model. The method can effectively detect weak noise interference, the approximation degree of the output result to the actual measurement data is high, and the aviation gravity gradient measurement precision is greatly improved.

This invention discloses a method for measuring gravity gradient based on an elastic beam. The steps include: constructing two identical measurement units, each unit comprising an angle measuring instrument, an elastic beam, and a mass block. The mass block is positioned at the tail end of the elastic beam, and the fiber optic loop of the angle measuring instrument is positioned on the mass block. The mass of the elastic beam is much smaller than the mass of the mass block. When measuring the diagonal component Γ in the i-direction of the gravity gradient... ii During measurement, the first ends of the two elastic beams are fixedly connected to a base, and the elastic beams in the two measuring units are placed parallel and symmetrically along the i-direction; the distance between the two mass blocks and the axis of symmetry is h; then the diagonal component Γ is calculated using the formula. ii When performing the off-diagonal component Γ in the gravity gradient ji During measurement, the elastic beams in the two measurement units are placed end to end along the j direction.