106 results about "Global coordinate system" patented technology

This invention discloses an AR-assisted puncture navigation spatial registration method and system based on environmental reference features, relating to the field of medical image navigation. The system includes an augmented reality navigation device, a permanent ceiling marker, and a temporary marker board. The augmented reality navigation device includes a binocular augmented reality camera group, a global tracking camera, a global spatial registration module, and a display module. The binocular augmented reality camera group constructs a binocular overlapping field of view, acquiring the pose information of the binocular augmented reality camera group relative to the temporary marker board during the calibration phase, and acquiring near-field images of the surgical area in real time during the surgical phase and displaying them on the display module. The global tracking camera acquires the pose information of the global tracking camera relative to the global coordinate system of the ceiling. The global spatial registration module solves the extrinsic parameter matrix between cameras and the environmental relationship matrix based on the pose information. During the surgical phase, the path planned by the imaging equipment is converted into a real-time navigation path and superimposed on the display module. This solves the complex calibration problem under non-overlapping fields of view.

This application relates to a hydraulic control optimization method, device, equipment, and medium for sector pre-assembly fixtures. It includes: establishing a global coordinate system and a sector pre-assembly fixture coordinate system, and determining rigid body transformation relationships; determining the current pose of the sector pre-assembly fixture and the target position of the sector to be transferred, and determining the initial position of the sector to be transferred; transferring the sector to be transferred from its current position to its initial position using the sector pre-assembly fixture; and, while the sector pre-assembly fixture is within a preset range, determining the gap and deviation of at least one measuring point on the sector pre-assembly fixture based on the current pose and rigid body transformation relationships, determining the target control strategy, and providing early warning and / or controlling multiple cylinder groups of the sector pre-assembly fixture. This solves the problems of high learning costs, high risk of misoperation, low adjustment efficiency, insufficient collision avoidance margin, and prominent safety hazards in heavy-duty operations in related technologies, improving the safety, efficiency, and repeatability of the transfer and alignment process.

This invention discloses a method for analyzing the features of crystal electron diffraction patterns based on computer vision, belonging to the field of image processing technology. It solves the problems of low detection efficiency in existing technologies, lack of prior knowledge of crystallographic physics constraints, insufficient noise resistance, and lack of end-to-end quantitative analysis in deep learning methods for diffraction patterns. The method includes: constructing an electron diffraction pattern dataset and training a model; detecting local bounding boxes on sub-patterns of the electron diffraction pattern to be inferred according to a set block size and sliding step size, then superimposing pixel offsets to map back to the global coordinate system; removing redundant boxes through non-maximum suppression to generate an initial set of diffraction spot center coordinates; constructing a lattice filtering algorithm based on the random sampling consensus algorithm to eliminate noise interference and obtain a corrected coordinate set; identifying the local diffraction pattern symmetry based on the number and angular features of diffraction spots in the neighborhood and calculating local geometric parameters to generate quantitative characterization data.

The application relates to the technical field of camera pose tracking, and discloses a low-cost camera six-degree-of-freedom tracking method, which comprises the following steps: acquiring three-dimensional coordinates of a Pivot in a virtual scene global coordinate system, a body coordinate system offset vector of the Pivot to a camera CMOS optical center, and an installation angle deviation matrix of an IMU relative to a camera body; and based on sensing data collected by the IMU, a pose rotation matrix in an IMU coordinate system is solved, and after installation angle deviation compensation and Pan zero point offset compensation are performed, the technical problem that in the prior art, when only relying on a low-cost inertial measurement unit (IMU), position integral error accumulation cannot be avoided, and after discarding visual collection and a high-precision mechanical encoder, it is difficult to balance hardware low cost, environmental adaptability and pose output stability is solved. The application provides a low-cost camera six-degree-of-freedom tracking method.

The application discloses a rice and wheat lodging three-dimensional attribute detection and distribution map construction method for a combine harvester, an electronic device and a computer readable storage medium. The method uses a vehicle-mounted binocular vision to obtain field images and depth information, segments a lodging area through a deep learning model, and then calculates three-dimensional attributes such as the area, position, angle and direction of the lodging area. Through displacement-based key frame screening and overlap degree judgment, multiple frame detection results are fused in a global coordinate system, and finally a spatial distribution map reflecting the overall lodging condition of a field plot is constructed, thereby providing a precise sensing basis for intelligent operation of the combine harvester.

This invention relates to an ultrasound endoscope probe, an ultrasound endoscope system, and its working method. The ultrasound endoscope probe includes multiple convex array transducers arranged in an array on a mounting plate. The mounting plate has a retracted position and an extended position. When the mounting plate is in the retracted position, the connecting surface is abutted against the mating inclined surface. When the mounting plate is in the extended position, the working surface is perpendicular to the central axis of the endoscope catheter. The ultrasound endoscope system includes a signal synchronization module, a data acquisition module, a data processing module, and a display module. By constructing a mapping relationship between the probe coordinate system and the BEV global coordinate system, a three-dimensional voxel mesh is generated to segment blood vessels and tumor tissue, ultimately achieving three-dimensional reconstruction. This invention overcomes the shortcomings of traditional ultrasound imaging, such as low vascular discrimination and large three-dimensional reconstruction errors, effectively improving imaging and segmentation accuracy, clearly displaying the relationship between lesions and adjacent blood vessels, shortening operation time, improving the safety of minimally invasive operations, reducing the burden of diagnosis and treatment for patients, and demonstrating significant clinical application value.

The application discloses a method for determining the elevation of a giant mixed-flow type hydro-generator set during overall replacement of a stator, and belongs to the technical field of installation of hydroelectric generation equipment. The method is characterized by the following steps: arranging laser displacement and inclination sensors on the stator lifting lugs and in the circumferential direction, collecting multi-source heterogeneous data and aligning the data based on millisecond-level timestamps; uniformly mapping the data to a global coordinate system with the center line of the fixed guide vane of the ring as a reference to construct a unified spatial posture framework; dynamically inhibiting displacement fluctuations caused by interference such as elongation of the steel wire rope and deformation of the crossbeam by using Kalman filtering; fusing the filtered displacement and inclination data to determine the tilting state of the stator as a whole by weighted average; further combining particle filtering to estimate the influence of the deformation of the crossbeam on the trajectory of the center of mass, and fitting the trajectory of the center of mass by using the least square method to calculate the elevation value in real time; when the elevation deviation is out of limit, the fusion parameters are optimized through a feedback loop to realize closed-loop regulation and control of the elevation and the posture. The application significantly improves the precision and stability of the determination of the elevation of the center of mass during the hoisting of a kiloton-class stator, and guarantees the safety and efficiency of the overall replacement operation.

The application discloses a laser processing galvanometer splicing precision closed-loop control method and system, relates to the technical field of galvanometer control, and comprises the following steps: acquiring theoretical parameters of a galvanometer system and establishing a theoretical global coordinate system; extracting local trajectories of galvanometers in a splicing area in a processing image and performing preliminary space-time alignment; constructing a distance constraint set in the splicing area; constructing an over-determined constraint equation set to solve relative geometric errors of adjacent galvanometers; recursively decomposing error time series; establishing an error model and predicting future short-time errors; generating a feedforward compensation amount to real-time correct control instructions; continuously updating trajectories, constraints and models; and introducing a forgetting mechanism to reduce the influence of historical data. The application realizes high-precision online closed-loop dynamic control of splicing errors, eliminates the dependence on complex offline calibration, enhances the accuracy of the system to time-varying interference through adaptive weights and predictive feedforward, and comprehensively improves the precision consistency and stability of large-area laser processing.

The application discloses a floating elastic disc and bottom-coupling cylinder coupling water dynamic force evaluation method and system, comprising: establishing a multi-structure wave action model; defining a global coordinate system, a disc local polar coordinate system and a cylinder local polar coordinate system; dividing a fluid region into a disc lower internal domain, an external domain and a cylinder non-inlet flow region; constructing a velocity potential expression satisfying seabed impermeability, a free liquid surface, water elasticity coupling, disc free boundary and cylinder wall impermeability conditions; through vertical characteristic function expansion and coordinate translation addition theorem, converting a diffraction interference relationship into an algebraic equation group; solving coefficients and calculating a wave diffraction field, disc response, free surface elevation, disc vertical exciting force and cylinder horizontal exciting force. The method can simultaneously consider wave interference between a flexible floating structure and a rigid fixed structure, water elasticity deformation and multiple scattering feedback, and provides a semi-analytical evaluation means for water dynamic response prediction of a floating photovoltaic unit and a single-pile foundation adjacent arrangement.

It assists in the operation of work machines equipped with a tilt rotator. [Solution] The measurement value acquisition unit acquires measurement values ​​from multiple sensors. The attitude calculation unit calculates the attitude of the attachment relative to the vehicle body based on the measurement values. The intervention control unit determines a virtual rotation axis based on the calculated attitude of the attachment. The operation signal acquisition unit acquires an operation signal from the operation device to operate the support unit. Based on the calculated attitude of the attachment and the operation amount indicated by the operation signal to operate the support unit, the intervention control unit generates a control signal for a tilt rotator to rotate the attachment around the virtual axis rotation so that the axial direction of the virtual rotation axis in the global coordinate system is maintained and the cutting edge of the attachment approaches parallel to the design plane. The output unit outputs the generated control signal.

The present application relates to the field of laser measurement technology, and more particularly to a kind of steel rail piece geometric dimension intelligent measurement method based on laser scanning.The present application includes the following steps: measurement preparation and system calibration;Laser scanning data acquisition;Point cloud data preprocessing;Geometric dimension intelligent calculation, based on the profile feature extraction of rail head, rail waist and rail bottom of each section profile point cloud after standardization;Measurement result output and storage.The present application constructs global reference axis of steel rail, converts local coordinates of each section to global coordinate system and compensates scanner attitude deviation, establishes continuity constraint of adjacent section profile feature parameters according to steel rail model, obtains optimal profile feature parameters through global optimization, can stably extract profile features of rail head, rail waist and rail bottom under unified reference, reduces the influence of attitude deviation and point cloud noise, and realizes reliable calculation of geometric dimension of steel rail section, full-length straightness and twist degree form error.

The present application relates to a mobile platform trajectory planning and positioning correction method for large-size measurement scenarios, comprising laying out feature marker points, obtaining feature marker point coordinates in the digital model coordinate system and the actual workpiece coordinate system; solving and optimizing the rigid transformation matrix of the digital model coordinate system and the actual workpiece coordinate system; mapping the theoretical trajectory points in the workpiece CAD digital model to the actual workpiece surface and optimizing, realizing the operation trajectory planning of the mobile platform; based on the chain matrix relationship between each coordinate system, real-time solving the pose matrix of the mobile platform in the global coordinate system and calculating the positioning error optimization, realizing the global positioning of the mobile platform; obtaining the actual trajectory point set of the mobile platform under the binocular vision system for dynamic correction. The present application meets the high-precision and automated operation requirements in large-size measurement scenarios, has high-precision positioning and closed-loop control characteristics, and is suitable for the automated measurement tasks of large-size components in the fields of aerospace, energy equipment, etc.

A cooperative positioning method, a cooperative positioning device, an electronic device, and a computer program product are provided. In the cooperative positioning method, a first electronic device is able to accurately determine a pose deviation based on a first pose of the first robot in a local coordinate system of the first robot, second poses of second electronic devices, and first distances between the first electronic device and the second electronic devices. The first pose of the first electronic device is allowed to be optimized based on the pose deviation, thereby obtaining a target pose of the first electronic device. In other words, the first electronic device is able to accurately determine a pose in the global coordinate system without any external device, thereby improving accuracy and stability of positioning of the first electronic device.

This invention relates to the field of ship unloader technology and discloses a method for achieving closed-loop anti-sway control of the grab bucket based on lidar calculation. The method includes: obtaining point cloud data of the grab bucket using lidar scanning during coal unloading operations; calculating the seven-dimensional parameters of the grab bucket's three-dimensional detection frame corresponding to the point cloud data using a grab bucket spatial positioning algorithm; matching the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system using spatial coordinate registration technology to calculate the grab bucket's pose in three-dimensional space; calculating the real-time spatial swing angle of the grab bucket using a spatial geometric interpolation algorithm; predicting the instantaneous velocity vector of the grab bucket at the lowest point of its swing trajectory using a dynamic model; generating a reverse velocity command that is opposite in direction and matches the magnitude of the instantaneous velocity vector; and applying the reverse velocity command to the grab bucket to achieve closed-loop anti-sway control. This invention achieves closed-loop anti-sway control of the grab bucket during dynamic ship unloading operations, improving the safety of ship unloading operations.

The application provides a large image target positioning method and device, equipment and storage medium, which are applied to the technical field of image positioning. A plurality of local sub-images covering a to-be-detected object are acquired, then coarse positioning is performed on the local sub-images to quickly determine a region of interest, fine positioning is performed in the region of interest, sub-pixel level features are extracted, and local sub-pixel level coordinates are calculated, so that the positioning precision is greatly improved. Space transformation parameters between adjacent local sub-images are calculated, and the parameters are used to map local position information to a global coordinate system. The strategy of combining local fine positioning and global unified mapping avoids information loss and precision reduction caused by scaling in traditional large image processing, solves the problems of repeated detection and inaccurate splicing that may occur in slice processing, and has the advantages of improving the accuracy and efficiency of large image target positioning.

This application discloses a method and system for detecting the motion state of an actuator inside an underwater unmanned submersible in the field of computer vision measurement technology. The method uses a vision system to perform non-contact measurement of the motion state of the actuator, avoiding problems such as mechanical wear, salt water corrosion, and electromagnetic interference, which helps to simplify the structure and improve reliability. It also uses a first deep learning model to perform global feature fusion processing on a first image, so that each pixel in the first image is fused with global context features, and uses a second deep learning model to identify and track a first marker point on the moving part of the actuator. Based on the spatiotemporal motion trajectory sequence of the first marker point and the second coordinate information of the first marker point in the global coordinate system of the submersible, the motion state of the actuator can be determined, meeting the needs of real-time monitoring. At the same time, it overcomes environmental interference such as low light, turbidity, and refraction underwater, which helps to improve detection accuracy and reliability.

The utility model discloses a kind of punching device for intelligent combination cabinet production, including: workbench, its top end is fixedly connected with limiting square, limiting square is used for combination cabinet board punching inside;The top end of workbench is fixedly installed with total controller, it is used to control the operation of overall device;Drilling structure, its main part is set to fixedly installed in the servo motor inside of connecting installation cylinder. The utility model establishes the double-layer coordinate system of limiting square global coordinate system and drilling cooperation component internal fine adjustment coordinate system, and realizes the accurate linkage of both, accurate mapping can be carried out to the fine adjustment coordinates of drilling cooperation block from global drilling point, realize the accurate positioning of hole position;Drilling cooperation block is directly located just below board drilling point, provides accurate guidance and support for drilling bit, greatly improves drilling perpendicularity and dimensional accuracy, avoids the impact of drilling bit possibly existing to workbench, guarantees the continuity and stability of drilling work.

The application relates to the technical field of calibration, and discloses a single-station-based rotating shaft calibration method, which comprises the following steps: obtaining a local initial point cloud by rotating scanning a house to be measured by a three-dimensional scanner, and calculating the transformation relationship between the local initial point cloud and a rotating shaft coordinate system to obtain the relative initial external parameter of the three-dimensional scanner and the rotating shaft; extracting a plane feature of the local initial point cloud in the rotating shaft coordinate system to obtain a plane point cloud and an index associated with the plane point cloud, and processing the plane point cloud based on the relative initial external parameter and the index associated with the plane point cloud to obtain a global local point cloud in a global coordinate system; constructing a target optimization function by using the index associated with the plane point cloud and the global local point cloud in the global coordinate system, and iteratively optimizing the relative initial external parameter by using the target optimization function to obtain a relative external parameter. The method provided by the application not only ensures the accuracy of the relative external parameter, but also reduces the time cost and improves the house measurement efficiency.

Embodiments of the present application disclose an intrusion UAV interception method and system based on visual and data fusion. Embodiments of the present application can acquire a current image of an intrusion UAV, and determine a current relative position between the intrusion UAV and an interception UAV. Based on the current relative position and current pose data of the interception UAV in a global coordinate system, a current absolute position of the intrusion UAV is determined. The current speed information of the intrusion UAV is calculated, and based on the current speed information and the current absolute position, a current observation motion state is obtained. Through a Kalman filtering algorithm, a state update is performed to obtain a current corrected motion state. Based on the current corrected motion state of the intrusion UAV and the historical corrected motion state corresponding to the intrusion UAV in a historical time period, a motion trajectory of the intrusion UAV in a future prediction time domain is predicted. Based on the motion trajectory, the interception UAV is controlled to perform an interception task on the intrusion UAV. Thus, embodiments of the present application improve the interception success rate.

The present disclosure relates to methods (200; 300; 400) for use in a moving platform for initialization of a visual-inertial odometry system (100) comprising a camera (1) and an inertial measurement unit (2), IMU. The methods comprise determining (201) point correspondence between at least a first image captured by the camera and a textured 3D model of an environment containing 3D coordinates given in a predetermined global coordinate system. The methods further comprise determining a relative rotation between the predetermined global coordinate system used for the camera and a IMU coordinate reference system, or estimating (210) a relative translation and rotation between the first and second images in a scale of the predetermined global coordinate system using the determined first and second point correspondences, said estimate indicating the scale for movement of the camera (1) for use in initialization of the visual odometry system.

The application discloses a six-degree-of-freedom pose estimation method, device and equipment of miniaturized instruments and a medium, relates to the field of space tracking and pose estimation, and comprises the following steps: constructing a dual five-degree-of-freedom sensor assembly; the dual five-degree-of-freedom sensor assembly comprises a first five-degree-of-freedom electromagnetic sensor and a second five-degree-of-freedom electromagnetic sensor, and the dual five-degree-of-freedom sensor assembly is pre-calibrated with a first vector; a first position vector and a direction angle of the first five-degree-of-freedom electromagnetic sensor in a global coordinate system are acquired, and a second position vector of the second five-degree-of-freedom electromagnetic sensor in the global coordinate system is acquired; based on the first position vector and the second position vector, a second vector of a measurement center of the second five-degree-of-freedom electromagnetic sensor relative to a measurement center of the first five-degree-of-freedom electromagnetic sensor in the global coordinate system is determined; rotation transformation information corresponding to rotation of the first vector to the second vector is determined, and the six-degree-of-freedom pose of a to-be-tracked part is determined by using the rotation transformation information and the direction angle.

This invention discloses a composite measurement method, device, system, medium, and program product. By integrating global multi-view visual positioning and local fringe projection measurement technology, it accurately corrects the motion error of an industrial robot using externally measured pose. First, it completes multi-dimensional accurate calibration of local measurement, global positioning module, and hand-eye coordination, constructing a high-precision unified global coordinate system covering the entire measurement space. Then, through hardware triggering, it achieves strict spatiotemporal synchronization of local 3D topography data and robot end-effector global pose data, and combines intelligent path planning to complete a full-coverage scan of large-size structures, calculating the high-precision six-DOF global pose of the robot end-effector detached from its own sensing system. Subsequently, it accurately converts the local point cloud to the global coordinate system and completes seamless stitching and fusion of noise reduction, coarse registration, and fine registration, realizing high-precision, high-efficiency, and automated 3D topography measurement of large-size structures, ensuring the global consistency and accuracy reliability of the measurement results.

This invention provides a system, method, and computer program product for dynamic reconstruction of robot trajectories under large language model task interaction. It includes: constructing a global coordinate system point cloud based on sensor data, obtaining point clusters through spatial clustering, constructing a local geometric tensor matrix and calculating hardness coefficients to identify hard agglomeration regions; dividing the global point cloud into point cloud voxels, selecting task-related voxel sets, and calculating voxel physical resistance feature weights and comprehensive cost values. It plans an environmental reconstruction path from the robot to the agglomeration region, sets a breaking parameter sequence based on resistance weights, and drives the breaking mechanism. Based on torque data during the breaking process, it identifies the critical point of agglomeration breakage through time-domain feature analysis, calculates the environmental reverse action gain signal, and corrects the corresponding voxel resistance weights. Based on the corrected resistance weights, it again achieves dynamic trajectory reconstruction through a heuristic path search algorithm. This invention realizes intelligent, closed-loop, and adaptive robot trajectory planning.

This application discloses a method, apparatus, equipment, and storage medium for all-position submerged arc welding of pipelines based on global 3D reconstruction, relating to the field of welding automation technology. The method includes: acquiring 3D point cloud data of the outer surface of the pipeline to be welded, and establishing a global coordinate system for the pipeline based on the 3D point cloud data; determining a welding path based on the 3D point cloud data within the global coordinate system; controlling a welding execution device to weld along the welding path; performing real-time internal defect detection on the welded seam after welding begins, and obtaining defect detection results; and optimizing welding process parameters in real-time based on the defect detection results until welding is completed. This application can improve the welding quality of pipeline welds.

The present application relates to a multi-machine cooperative mapping method based on hierarchical boundary point detection algorithm and electronic equipment, the method comprises the following steps: constructing a centralized system by multiple mobile robots equipped with laser radar and depth camera, each robot uses Gmapping algorithm for local mapping and positioning; the system uses map fusion technology based on feature point matching, extracts the features of the local map and calculates the transformation matrix to unify the local map of each robot to the global coordinate system; using the cooperative exploration strategy based on the front point, combined with the multi-machine task allocation algorithm, the efficient cooperative coverage of indoor unknown environment is realized. Through the multi-machine centralized cooperative architecture and multi-source sensor fusion technology, the present application solves the problem of low efficiency and limited coverage range of single robot mapping, improves the integrity and real-time performance of mapping in complex indoor environment, and can be widely applied to indoor autonomous navigation robots, intelligent warehouse inspection systems, indoor rescue robots, building intelligent security and other fields.

This invention relates to the field of intelligent manufacturing technology, and more particularly to a self-aligned stack positioning method and system for welding multi-layer structures. The method first extracts the microstructure of the flow channels and the geometric features of the edges on the plate, constructing a spatial constraint model to eliminate false features. Then, the features are mapped to a global coordinate system, and the pose deviation is calculated based on image signal-to-noise ratio weighting. Simultaneously, a thermo-mechanical coupling model is constructed to obtain the nonlinear displacement field of the plate under welding thermal cycling, and the relative expansion vector is calculated using the thermal expansion center as a reference to generate a thermal pre-compensation value to offset thermal deformation. By superimposing the pose deviation and the thermal pre-compensation value, the motion platform is driven to perform the initial alignment. Finally, feature frequencies at different depths are stripped in the frequency domain to infer the cumulative offset of the multi-layer stack and construct an error evolution curve, achieving adaptive correction of subsequent positioning parameters.

The application provides a vehicle body vibration positioning method and system, which comprises the following steps: pasting sensing optical fibers along a preset path on a vehicle body and setting optical markers on the optical fiber path at a predetermined number of calibration points; scanning the vehicle body provided with the optical markers to obtain three-dimensional coordinates of each optical marker point in a global coordinate system of the vehicle; applying mechanical excitation around each optical marker point, obtaining fiber coordinates of each optical marker point based on time domain reflection analysis, and constructing a coordinate relationship mapping table of the fiber-vehicle body according to the fiber coordinates of the optical marker points and the three-dimensional coordinates of the optical marker points in the global coordinate system of the vehicle; if a vibration signal is detected during the operation of the vehicle, the fiber coordinates of the vibration signal are extracted through signal analysis, and the source of the vehicle vibration signal is positioned based on the coordinate relationship mapping table of the fiber-vehicle body. Through the scheme, the efficiency and accuracy of vehicle vibration positioning can be improved.

The application provides an intelligent ship identity recognition method and system based on artificial intelligence, and the method comprises the following steps: training original samples through structure constraint enhancement, and constructing a model conforming to real maritime imaging conditions; generating stable target sequences by using joint segmentation and identification bearing area guide mechanism on input videos; continuously updating the frames by tracking feature extraction model in a global coordinate system to realize target tracking; detecting texts on the tracking sequences, and suppressing single-frame errors by using the probability fusion of the same character positions in multiple frames; and finally, matching the recognition results with an identity database index to complete verification. The application significantly improves the accuracy and stability of ship identity recognition in complex environments, and is mainly used in port monitoring, maritime supervision and ship automatic identification scenes.

The application provides a gate position correction method and a correction mechanism, and relates to the technical field of gate control of a hydropower station.The method comprises the following steps: constructing a trajectory prediction model and a global coordinate system; inputting a gate state vector into the trajectory prediction model to obtain a predicted trajectory; determining a predicted offset vector, a predicted offset rate and a correction critical time; selecting a correction start time; obtaining a predicted trajectory point and a predicted offset vector corresponding to the correction start time to obtain a correction start position and a correction start offset vector; determining a target position of a contact point based on the correction start offset vector and a current position of the contact point of the correction mechanism; moving the contact point of the correction mechanism to the correction start position at the correction start time; and moving the contact point of the correction mechanism to the target position of the contact point during the correction. The method can predict the offset trend of the gate in advance, rather than reacting after the actual offset occurs, thereby shortening the time interval from discovering the problem to taking action.