A method and system for high-precision measurement and automatic alignment of the outer perimeters of a first ship block and a second ship block.

Abstract

The present invention is a high-precision measurement and automatic butt-joint method applicable to ship blocks with no margin. First, automatic calibration is performed on the measuring device, and the steps of measuring the visible key points on the block butt-joint surface and the coordinate positions of each trolley target ball are carried out. Coarse alignment is performed on the fixed block and the moving block to obtain the initial rotation matrix and the initial translation matrix of the key point set on the block butt-joint surface, and the accurate rotation matrix and the accurate translation matrix are obtained. The moving block butt-joint method is determined, and based on the coordinate positions of the trolley target balls, the position of the trolley relative to the moving block is determined. By combining the accurate rotation matrix and the accurate translation matrix, the trolley motion planned trajectory is obtained. The trolley motion trajectory is compensated to obtain the compensated path butt-joint trajectory. The trolley position data measured by two measuring devices are fused, and the trolley motion trajectory is fed back for control. A high-precision measurement and automatic butt-joint method applicable to ship blocks with no margin is disclosed. The method of the present invention realizes the automatic butt-joint of ship blocks through the automatic calibration of the measuring device, data calculation, automatic attitude adjustment, compensation prediction and control feedback.

Description

[Technical Field]

[0001] The present invention The outer perimeters of the first ship block and the second ship block This invention relates to a high-precision measurement and automatic butt-matching method. In the following explanation, the first vessel block will be referred to as the fixed total stage, the second vessel block as the movable total stage, and the first and second vessel blocks together will be referred to as the vessel consultation. [Background technology]

[0002] In shipbuilding, the butt joint of a ship's seams is directly related to the overall manufacturing level of the ship. The quality of the weld largely depends on the accuracy of the butt joint of the ship's seams. There are many factors that affect the butt joint of a ship's seams, but among them, measurement error, attitude calculation error, and attitude adjustment error are the three most significant influencing factors. Most patents reduce errors by proposing attitude measurement methods. For example, Chinese patent CN200810229112.9 discloses two butt joint methods for shipbuilding, measuring the coplanarity of the joints through a laser longitude meter. However, it does not take into account the mounting error of the device itself, the situation in which important points in the seams are shielded during measurement, or data conversion errors, thus affecting the butt joint accuracy of the ship's seams. [Overview of the project] [Problems that the invention aims to solve]

[0003] Objective of the Invention: The objective of the present invention is to provide a high-precision measurement and automatic matching method suitable for ship total stage measurement, data calculation, automatic attitude adjustment, compensation prediction, and control feedback-based automatic matching method. [Means for solving the problem]

[0004] Technical proposal: The present invention provides a high-precision measurement and automatic matching method suitable for the tightly packed total sections of a ship, Step S1 involves fixing a fixed total stage in place and placing a movable total stage on an adjustable trolley, establishing common reference points on the ground on both sides of the fixed total stage and the movable total stage, establishing corresponding important points on the abutting surfaces of the fixed total stage and the movable total stage, attaching a measuring device including a first laser tracker, a second laser tracker and a laser rangefinder, locating the measuring device using the common reference points, calculating the position of the measuring device in the global coordinate system, measuring the coordinates of each important point using the first laser tracker, measuring the three-degree-of-freedom movable plane position coordinates of the trolley using the second laser tracker, and converting both the coordinates of each important point and the three-degree-of-freedom movable plane position coordinates of the trolley into the global coordinate system. Step S2 involves roughly matching the fixed total stage and the moving total stage, obtaining the initial rotation matrix and initial translation matrix of the important point set of the fixed total stage abutment surface and the moving total stage abutment surface, and further obtaining the accurate rotation matrix and accurate translation matrix using the iterative nearest-neighbor ICP algorithm, wherein each important point of the moving total stage is used as the center of a circle, a circle is drawn with a predetermined distance as the radius, the weight of each important point of the moving total stage is calculated based on the number of pipes in each circle, three important points with the maximum sum of weights and that are not collinear are selected to form a plane, the center of mass of this plane is found, and based on the principle of random combinations, three other sets of important points with the maximum sum of weights and that are not collinear are selected. Step S2 includes selecting important points, forming a plane, finding the center of mass of this plane, sequentially finding the center of mass corresponding to the important points of the moving stage in this manner, finding the center of mass corresponding to the important points on the fixed stage using the same method, selecting three pairs of mutually corresponding and non-collinear center of mass on the fixed stage and the moving stage, establishing the moving stage butt plane coordinate system and the fixed stage butt plane coordinate system respectively through the three-point alignment method, calculating the two coordinate systems, finding the initial rotation matrix and initial translation matrix, achieving a rough match between the moving stage and the fixed stage, and substituting the initial rotation matrix and initial translation matrix into the iterative nearest-neighbor ICP algorithm to find the exact rotation matrix and exact translation matrix. Step S3 involves determining the method for matching the total moving stages, which includes two stages: in the first stage, adjusting the displacement of the three degrees of freedom of the moving stage in the x, y, and z directions and the rotation direction around the x and z axes; in the second stage, adjusting the displacement of the moving stage in the y direction; determining the position of the trolley relative to the moving stages based on the three degrees of freedom moving plane position coordinates of the trolley in the global coordinate system obtained in step S1; combining the exact rotation matrix and exact translation matrix obtained in step S2, determining the distance the trolley should move in each degree of freedom through inverse kinematics; and performing a path matching trajectory plan on the trolley using a 5th-order polynomial fitting method to obtain the trolley motion plan trajectory. Step S4 involves using a BP neural network to predict the error caused by deformation at the connection point between the trolley and the moving stage during path matching adjustment, training a BP neural network consisting of one input layer, three implicit layers, and one output layer using historical data, obtaining error values ​​due to deformation of the bottom plate member of the moving stage under different velocities, different accelerations, and different weights under the same policy through training predictions, thereby compensating for the distance the trolley should move in each degree of freedom obtained in step S3 during trolley path matching adjustment, and recalculating the trolley motion plan trajectory in step S3 to obtain the compensated path matching trajectory, When controlling and adjusting the trolley, the second laser tracker measures the coordinates of the trolley target ball for each trolley until the actual path matching trajectory of the trolley matches the path matching trajectory compensated in step S4, and at the same time, the laser rangefinder measures the distance traveled in the three degrees of freedom direction of each trolley, and step S5 is performed to fuse the data measured by the second laser tracker and the laser rangefinder and provide real-time feedback on the adjustment status of the trolley.

[0005] Furthermore, in step S1, target balls are attached to each important point position and to the three-degree-of-freedom movement planes of the trolley, including the bottom surface, middle surface, and top surface of the trolley. The first laser tracker is used to measure the coordinates of the target balls on each important point, and the second laser tracker is used to measure the coordinates of the trolley target balls on each degree-of-freedom movement plane of the trolley. The number of first laser trackers ensures that all critical point target balls can be measured, and the position of each first laser tracker ensures that the most critical point target balls can be measured. The number of second laser trackers ensures that the target ball can be measured on the three-degree-of-freedom movement plane of all trolleys, and the position of each second laser tracker ensures that the target ball can be measured on the three-degree-of-freedom movement plane of the most numerous trolleys.

[0006] The specific method for rough matching in step S2 is as follows: (101) Calculate the weight of each important point on the moving deck, and draw a circle with each important point as the center and a radius of half the width of the ship's deck. The weight w1 of the i-th important point on the moving deck is as follows:

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[0007] The calculation methods of the accurate rotation matrix and the accurate translation matrix in step S2 are as follows: (201) Establish the moving total stage mating surface coordinate system and the fixed total stage mating surface coordinate system. Take the g j point as the coordinate origin, take the direction vector from g j to g k as the x - axis, construct a unit vector.

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[0008] The trajectory plan for the total movement path in step S3 is specifically as follows, using a stepwise attitude adjustment method: (31) The total moving stage is rotated by an angle α around the x-direction to move the ship's moving stage to a position horizontal to the x-axis, the total moving stage is rotated by an angle β around the y-direction to move the ship's moving stage to a position parallel to the y-axis, and the total moving stage is rotated by an angle γ around the z-direction to move the ship's moving stage to a position parallel to the z-axis, and the translation amounts in the two degrees of freedom directions, x and z, are adjusted simultaneously. (32) When the distance between the moving total stage and the fixed total stage reaches a predetermined distance threshold, the translation in the y direction is adjusted to avoid interference during the adjustment of the moving total stage due to the presence of the total stage pipe, and the trolley path matching trajectory is planned through the fifth-order polynomial trajectory method.

[0009] Furthermore, step S4 is specifically as follows: (41) Using a BP neural network, predict the butt error due to deformation of plate members of the moving total stage of ships of various shapes under the same acceleration, same velocity and different weights, under the conditions that the assembly environment is the same, the velocity and acceleration are the same, and the positions where the trolley supports the total stage are the same, the control variable is the weight of the moving total stage of the ship, and by extracting field data, predict the butt error due to moving total stages of different weights and calculate the butt error, obtain the compensation amount in the three degrees of freedom direction of each trolley, add the compensation amount to the trolley path butt trajectory planned in step S3, and adjust the trolley path butt trajectory. (42) The weight of the ship's moving sections, trolley position and assembly environment are controlled to be constant, thereby predicting the total section abutment deviation under different accelerations and velocities, and compensating for the three-degree-of-freedom motion trajectory of each trolley. The BP neural network input layer includes five neurons for selecting weight, velocity, acceleration, displacement and material properties; the implicit layer is set up in three layers and includes multiple neurons; and the output layer has one neuron which is the displacement compensation amount for each direction of each trolley.

[0010] Furthermore, step S5 is specifically as follows: The second laser tracker measures the trolley target balls placed on the trolley's three-degree-of-freedom movement plane, and simultaneously measures the trolley's three-degree-of-freedom motion using a laser rangefinder. The data measured by the second laser tracker and the laser rangefinder are then merged. If the second laser tracker detects that a trolley target ball is being obscured, the laser rangefinder replenishes the data. If the trolley's power is cut off or a malfunction occurs, the trolley feedback measuring device records the trolley's current position. If the trolley is powered back on or a contact failure occurs, the device continues to control the trolley path alignment trajectory until the alignment between the moving and stationary sections is complete.

[0011] The present invention provides a high-precision measurement and automatic matching system suitable for the tight total stage of a ship, A data collection and processing module for locating a measuring device based on a set common reference point, calculating the position of the measuring device in a global coordinate system, measuring the coordinates of each key point target ball on the fixed and movable total step abutment surfaces using the measuring device, simultaneously measuring the three-degree-of-freedom moving plane position coordinates of the trolley, and converting both the coordinates of each key point and the three-degree-of-freedom moving plane position coordinates of the trolley into a global coordinate system using singular value decomposition (SVD). Using each key point of the moving stage as its center, draw a circle with a predetermined distance as the radius, calculate the weight of each key point of the moving stage based on the number of pipes in each circle, sort the key points of the moving stage in ascending order of weight, select any three key points that have the maximum weight and are not collinear, form a plane, find the center of mass of this plane, and, based on the principle of random combinations, select any three key points other than the above pair that have the maximum sum of weights and are not collinear, form a plane, find the center of mass of this plane, and so on, sequentially find the center of mass corresponding to the key points of the moving stage, and follow the same method to find the key points on the fixed stage. The corresponding center of mass is determined, three corresponding pairs of center of mass on the moving and fixed sections are selected using the three-point alignment method, the moving and fixed sections are established based on the selected three corresponding pairs of center of mass on the moving and fixed sections, the moving and fixed sections are calculated, the initial rotation matrix and initial translation matrix are determined, a rough alignment between the moving and fixed sections is achieved, the initial rotation matrix and initial translation matrix are substituted into the iterative nearest-neighbor ICP algorithm, the exact rotation matrix and exact translation matrix are determined, and a rough and exact alignment module is established to achieve exact alignment. The trolley's position relative to the total moving stage is determined, and the method of matching the total moving stage includes two stages: in the first stage, the displacement of the three degrees of freedom of the total moving stage in the x, y, and z directions and the rotation direction around the x and z axes are adjusted; in the second stage, the displacement of the total moving stage in the y direction is adjusted; and based on the acquired three-degree-of-freedom moving plane position coordinates of the trolley in the global coordinate system, and the obtained accurate rotation matrix and accurate translation matrix, the distance the trolley should move in each degree of freedom is determined through inverse kinematics; and a path matching trajectory planning module performs a path matching trajectory plan on the trolley using a 5th-order polynomial fitting method based on this distance data. A deformation compensation module is used to predict errors caused by deformation of the bottom plate member of the moving stage at the connection point between the trolley and the moving stage during path matching adjustment using a BP neural network, to train a BP neural network consisting of one input layer, three implicit layers, and one output layer using historical data, to obtain error values ​​for deformation due to different velocities, different accelerations, and different weights under the same policy through training predictions, thereby compensating for the amount of movement of each degree of freedom of the trolley during trolley path matching adjustment, and to obtain the path matching trajectory after deformation compensation. When controlling and adjusting the trolley, the system includes a motion feedback module that uses a measuring device to measure the coordinates of the trolley target ball in each of the three degrees of freedom until the actual path alignment trajectory of the trolley matches the path alignment trajectory after deformation compensation, simultaneously measures the planar distance that each trolley moves in each of the three degrees of freedom using the measuring device, and fuses the target ball coordinates in each of the three degrees of freedom and the travel distance data for each trolley in each of the three degrees of freedom measured by the measuring device to provide real-time feedback on the adjustment status of the trolley.

[0012] The measuring device includes a first laser tracker, a second laser tracker, and a laser rangefinder. Target balls are attached to key point locations and to the three-degree-of-freedom movement planes of the trolley, including the bottom, middle, and top surfaces of the trolley. The first laser tracker is used to measure the target ball coordinates at each key point, the second laser tracker is used to measure the trolley target ball coordinates on the trolley, and the laser rangefinder is used to measure the planar movement distance in the three-degree-of-freedom direction of each trolley. The number of first laser trackers ensures that all critical point target balls can be measured, and the position of each first laser tracker ensures that the most critical point target balls can be measured. The number of second laser trackers ensures that the target ball can be measured on the three-degree-of-freedom movement plane of all trolleys, and the position of each second laser tracker ensures that the target ball can be measured on the three-degree-of-freedom movement plane of the most numerous trolleys.

[0013] The present invention relates to an apparatus and equipment, Memory for storing computer programs that can be executed on the processor, When the computer program is running, it includes a processor for performing steps of a high-precision measurement and automatic matching method adapted to the tight margins of the vessel. [Effects of the Invention]

[0014] Beneficial Effects: Compared to conventional technology, the remarkable technical effects of the present invention are as follows: To address the problem of relatively complex ship pipes that are difficult to align during the butt joint process and often result in poor alignment, the invention optimizes the three-point alignment method by employing a weighting system, thereby making the final determined orientation of the moving stage more accurate. To address the problem of the bottom plate member of the contact area between the ship's moving stage and the trolley being prone to deformation, the invention proposes using a BP neural network to predict errors due to the amount of deformation of the bottom plate member of the moving stage under different conditions, thereby compensating for these errors during the trolley adjustment movement. This reduces the influence of deformation of the bottom plate member of the moving stage on the butt joint of the stages and is advantageous in further improving the accuracy and quality of the butt joint between the two stages. [Brief explanation of the drawing]

[0015] [Figure 1] This is a flowchart of the butt joint method of the present invention. [Figure 2] This is a detailed flowchart of the butt joint method of the present invention. [Figure 3] This is a schematic diagram of the butt measurement system of the present invention. [Figure 4] This is a schematic diagram illustrating the establishment of each coordinate system in the butt joint system of the present invention. [Figure 5]This is a schematic diagram illustrating the distribution of key points in the butt joint system of the present invention. [Figure 6] This is a schematic diagram showing the distribution of each common reference point in the butt joint system of the present invention in a plan view. [Figure 7] This is a schematic diagram of the weight matching method for each important point in the butt joint method of the present invention. [Modes for carrying out the invention]

[0016] The present invention will be described in detail below with reference to the drawings and specific embodiments.

[0017] As shown in Figures 1 and 2, in the high-precision measurement and automatic matching method for ship stages of the present invention, first, the first to fourth laser trackers are localized by measuring a common reference point on the same side. After localization is complete, the first and second laser trackers measure the key point target balls of the two stages, and the third and fourth laser trackers measure the trolley target balls on the four trolleys. Based on the key point coordinates, the accurate rotation matrix and accurate translation matrix between the moving and stationary stages are determined using a weighted and optimized three-point alignment method and ICP algorithm. Simultaneously, the actual position of the trolleys before movement is determined by measuring the trolley target balls on the four trolleys. The stage matching method is then determined, and the above accurate rotation matrix, accurate translation matrix, and actual trolley position data are combined and the trolleys are matched through inverse kinematics. The system calculates the theoretical distance the trolley should travel with three degrees of freedom, and then uses a fifth-degree polynomial to plan its trajectory. The higher-level system visualizes and determines whether this trajectory plan causes interference between the ship's moving sections and the stationary sections. If interference occurs, it re-selects different path points and plans the path for the trolley. If there is no interference, the BP neural network predicts the error due to the deformation of the bottom plate member of the ship's moving sections in the different cases, thereby determining the amount of compensation required during the trolley's motion. Furthermore, trolley compensation is implemented using PLC control. Finally, during motion, the difference between the trolley's actual motion position and its theoretical motion position is determined by measuring the trolley target ball with a laser tracker and measuring each plane of the trolley with a laser rangefinder. This difference is then fed back into the trolley's movement position, and the trolley is controlled to achieve two-stage adjustment of the moving sections, thereby achieving high-precision alignment of the moving sections.

[0018] Specifically, this includes the following steps:

[0019] S1, a fixed total stage is fixed in place, and a movable total stage is placed on an adjustable trolley. Common reference points that are not easily deformed on the ground are set on the ground on both sides of the fixed total stage and the movable total stage. Important points corresponding to the abutting surfaces of the fixed total stage and the abutting surfaces of the movable total stage are set. Measuring devices including a first laser tracker, a second laser tracker, and a laser rangefinder are attached, and the measuring devices are localized using the common reference points (i.e., the first laser tracker, the second laser tracker, and the laser rangefinder localize their own positions by measuring the common reference points). The position of the measuring devices in the global coordinate system is calculated. After localizing the measuring devices, the first laser tracker measures the coordinates of each important point on the abutting surfaces of the movable total stage and the abutting surfaces of the fixed total stage. The second laser tracker measures the actual position coordinates of each trolley in the three-degree-of-freedom moving plane before adjustment. Both the coordinates of each important point and the actual position coordinates of each trolley in the three-degree-of-freedom moving plane before adjustment are converted to the global coordinate system.

[0020] As shown in Figure 3, the components are: 1- Fixed total stage, 2- Moving total stage, 3- First laser tracker, 4- Second laser tracker, 5- Third laser tracker, 6- Fourth laser tracker, 7- Three-dimensional attitude adjustment trolley, 8- Trolley target ball, 9- Laser rangefinder, 10- Fixed support column, 11- Common reference point target ball, 12- Important point target ball. The fixed total stage 1 is supported by four support columns 10, the four support columns arranged symmetrically in pairs, and the movable total stage 2 is provided on four three-dimensional attitude adjustment trolleys, each of which has a trolley target ball attached to the three-degree-of-freedom movement plane of the trolley for measuring and feeding back the trolley adjustment distance using a laser tracker, the three-degree-of-freedom movement plane of the trolley includes the bottom surface, middle surface and top surface of the trolley, six pairs of corresponding critical point sets are provided on the abutting surfaces of the fixed total stage and the abutting surfaces of the movable total stage, and a critical point target ball 12 is attached to each critical point location for subsequent measurement with the first laser tracker, eight pairs of common reference points are provided symmetrically on the ground on both sides of the ship's fixed total stage and movable total stage, and a common reference point target ball 11 is provided on each common reference point. The positions of the first and second laser trackers are set up to measure as many critical point target balls as possible using the laser trackers. The first and second laser trackers then measure the common reference point target ball on the same side as themselves, thereby determining their precise positions at that time and achieving positional alignment of the first and second laser trackers. At this time, the positions of the first and second laser trackers in the global coordinate system are calculated, and after alignment, the first and second laser trackers are used to measure the key point target balls of the fixed total stage and the key point target balls of the moving total stage.The third and fourth laser trackers are controlled to a lower level, and they are positioned so that the trolley target ball coordinates can be measured without obstruction. These positions are fixed, and the third and fourth laser trackers each measure the common reference point target ball on the same side. At this time, the positions of the third and fourth laser trackers are determined, and their positions in the global coordinate system are calculated. Furthermore, the trolley target ball coordinates for the four trolleys are measured. The measured target ball coordinates for each key point in the fixed and moving sections of the ship, as well as the trolley target ball coordinates for each trolley, are converted to the global coordinate system using singular value decomposition (SVD), and the target ball coordinates for each key point and each trolley target ball in the global coordinate system are obtained.

[0021] As shown in Figure 4, a global coordinate system O-XYZ is established, and a fixed total stage coordinate system O1-X1Y1Z1 and a movable total stage coordinate system O2-X2Y2Z2 are established. Based on the design drawings, important points P1-P6 that need to be measured to make the important position coordinates of the design drawings the fixed total stage abutment surface, and important points Q1-Q6 that need to be measured to make the movable total stage abutment surface are selected. The important points P1-P6 correspond one-to-one with Q1-Q6, and the location and distribution of the important points are shown in Figure 5. Sixteen specific common reference points are established on the total stage assembly ground, and the first eight common reference point reference points M1-M8 and the second eight common reference points M9-M 16This is symmetrical with respect to the axial midline of the fixed ship stage Y1, and the position and distribution of common reference points are shown in Figure 6. Four laser trackers are placed at positions I to IV, with the first laser tracker at position I, the second laser tracker at position II, the third laser tracker at position III, and the fourth laser tracker at position IV. The first laser tracker measures common reference points M1 to M8 on the ground, and by measuring the common reference points, the precise position of the first laser tracker is determined, establishing the coordinate system O3-X3Y3Z3 for the first laser tracker at position I. The first laser tracker placed at position I measures key points of the fixed ship stage and the moving ship stage, obtaining the coordinate positions in the coordinate system of the first laser tracker at position I of the measurable key points P1, P2, P3 of the fixed ship stage and the measurable key points Q1, Q2, Q3 of the moving ship stage. Similarly, the second laser tracker measures common reference points M9 to M 16 By measuring the coordinates of the second laser tracker, the precise position of the second laser tracker is determined, and the second laser tracker placement position II coordinate system O4-X4Y4Z4 is established. The second laser tracker measures the coordinate positions of the measurable critical points P4, P5, P6 of the ship's fixed stage and the measurable critical points Q4, Q5, Q6 of the ship's moving stage in the second laser tracker placement position II coordinate system. By fusing the coordinates of the critical points of the moving and fixed stages, the critical point coordinates of critical points P1, P2, P3, Q1, Q2, Q3 in the first laser tracker placement position I coordinate system O3-X3Y3Z3, and the critical point coordinates of critical points P4, P5, P6, Q4, Q5, Q6 in the second laser tracker placement position II coordinate system O4-X4Y4Z4 are converted to a global coordinate system, and the coordinates of each critical point in the global coordinate system are obtained.

[0022] Similarly, the third and fourth laser trackers are located on the same side as common reference points M1-M8 and M9-M8 on the ground. 16By measuring the common reference point, the precise positions of the third and fourth laser trackers are determined, establishing the third laser tracker's position in coordinate system III (O5-X5Y5Z5) and the fourth laser tracker's position in coordinate system IV (O6-X6Y6Z6). The third and fourth laser trackers then measure the actual coordinates of the trolley target ball on the trolley on the same side, respectively. The trolley target ball coordinates obtained using singular value decomposition (SVD) are converted to a global coordinate system to obtain the trolley's actual position before movement.

[0023] S2, rough matching is performed on the fixed total stage and the moving total stage, and the initial rotation matrix and initial translation matrix are obtained for the set of important points of the fixed total stage abutment surface and the moving total stage abutment surface, and the exact rotation matrix and exact translation matrix are obtained using the iterative nearest nearest point (ICP) algorithm. A circle is drawn with each important point of the fixed total stage as the center of the circle and a predetermined distance as the radius, and the weight of each important point of the fixed total stage is calculated based on the number of pipes in each circle, and three important points that have the maximum weight and are not collinear are selected to form a plane, and the center of mass of this plane is found, and based on the principle of random combinations, three important points other than the above set of combinations that have the maximum sum of weights and are not collinear are selected to form a plane, and the center of mass of this plane is found, and the centers of mass corresponding to the important points of the fixed total stage are found in this manner, and the moving total stage is found in the same manner The method involves determining the centers of mass corresponding to the key points mentioned above, selecting three pairs of mutually corresponding and non-collinear centers of mass on the fixed and moving sections, establishing the moving section butt plane coordinate system and the fixed section butt plane coordinate system through a three-point alignment method, calculating the moving section butt plane coordinate system and the fixed section butt plane coordinate system constructed through the three-point alignment method, determining the initial rotation matrix and initial translation matrix, achieving a rough alignment between the moving and fixed sections, and substituting the initial rotation matrix and initial translation matrix into an iterative nearest nearest (ICP) algorithm to determine the exact rotation matrix and exact translation matrix. This method allows for accurate butting of more pipes after the ship end faces have been butted, solving the problem of pipe butting being difficult and the number of accurate butts being small.

[0024] First, the data measured in step S1 is calculated, and the data calculation involves performing a fitting to the measured important point coordinates of the fixed total stage and the movable total stage, and the fitting involves first performing a rough alignment through the three-point alignment method on the measured important point set of the fixed total stage abutting surface and the movable total stage abutting surface of the ship, and optimizing the rough alignment method by matching it with pipe abutting, and includes the following.

[0025] (101) Using each key point of the moving stage as its center, draw a circle with a predetermined distance as the radius, calculate the weight of each key point of the fixed stage based on the number of pipes in each circle, rearrange the key points of the moving stage in ascending order of weight, select the three key points that have the maximum weight and are not collinear, form a plane, find the center of mass of this plane, select three points on the ship's moving stage that have the maximum weight and are not collinear, other than the above pair of combinations, connect them in order to form a plane, find the center of mass of this plane, find the centers of mass corresponding to the other key points of the moving stage in this manner, find the centers of mass corresponding to each key point on the fixed stage according to the same method, select three pairs of corresponding non-collinear centers of mass on the moving stage and the fixed stage, establish the moving stage butt plane coordinate system and the fixed stage butt plane coordinate system, respectively through the three-point alignment method, calculate the moving stage butt plane coordinate system and the fixed stage butt plane coordinate system constructed through the three-point alignment method, find the initial rotation matrix and the initial translation matrix, and achieve coarse alignment between the moving stage and the fixed stage.

[0026] When butting the decks of a ship, it is necessary to consider the precision of the pipe butt joints in the deck. Pipe measurement is done manually using a measuring ruler or other tool, with the closest plate member as the reference. The reference point for measuring ship pipes is generally the strong construction of the deck butt joint surface. Since the measurement points of the deck are generally at the connection points of the construction, a weighting of key points is introduced to better control the precision of pipe butt joints and to enable more pipe members to be butted perfectly. As shown in Figure 7, this embodiment describes this method using four of the six key points (Q1, Q2, Q4, Q5) of the deck butt joint surface of a ship to facilitate explanation. Multiple key points beyond four can be inferred according to this method. This method assigns weight to each key measurement point by calculating the number of pipes in each circle. The specific details of assigning weight are as follows: For Q1, with Q1 as the center, draw a circle R1 with radius R preferably being half the width of the fixed deck. The selection of the radius should not exceed the diagonal distance of the fixed deck. Similarly, draw the corresponding circles R2, R4, and R5 with Q2, Q4, and Q5 as the centers and R as the radius. The total number of moving stage pipes on the ship is M, and the circle R has the i-th important point on the moving stage as its center. i The number of pipes at the center of the pipes included is N i In this embodiment, i = 1, 2, 4, 5. The weight w1 of the i-th important point on the total moving stage is as follows:

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[0027] (102) The set of weights for all important points on the moving total is W={w1,...,w NIn this case, first select three important points whose sum of weights is maximum and which are not collinear, connect these three points in pairs to form a plane triangle, calculate the center of mass g1 of the triangle, and based on the principle of random combinations, select three important points other than the above pair whose sum of weights is maximum and which are not collinear, form a plane, find the center of mass g2 of this plane, and similarly follow this method to find the center of mass corresponding to the important points on the moving total stage.

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[0028] (103) The center of mass corresponding to the important point on the fixed total stage, in the same manner as above.

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[0029] Then, the initial rotation transformation matrix and initial translation matrix are obtained for the important point sets of the moving total-stage abutment surface and the fixed total-stage abutment surface, and the exact rotation matrix and exact translation matrix are determined.

[0030] (201) Establish a coordinate system for the moving total step abutting plane and a coordinate system for the fixed total step abutting plane, g j Let point be the origin of the coordinate system, g j from g k Let the direction vector be the x-axis, and construct a unit vector.

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[0031] In this embodiment, after determining the weight of each point, first select three important points whose sum of weights is maximum and which are not collinear, connect these three points in order to form a plane, and calculate the plane center of mass g1. Then, select three important points on the moving stage of the ship that have a maximum sum of weights and are not collinear, other than the above 1 set of combinations, connect these three points in order to form a plane, and calculate the plane center of mass g2. Finally, select three important points on the moving stage of the ship that have a maximum sum of weights and are not collinear, other than the above 2 sets of combinations, connect these three points in order to form a plane, and calculate the plane center of mass g3. Similarly, the two corresponding centers of mass on the fixed stage are calculated as follows:

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[0032] Let point g1 be the origin of the coordinate system, and the direction vector from g1 to g2 be the x-axis. Construct a unit vector.

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[0033] S3. First, a method for butting the ship's moving stages is established. Unlike butting other objects, the area of ​​the ship's moving stages is too large, so it is necessary to adjust it in stages and ensure that there is no interference when adjusting the butting attitude. Therefore, the entire process of butting the moving stages is divided into two stages. In the first stage, the rotation of the three degrees of freedom of the moving stages around the x, y, and z axes and the translation in the x and z directions are adjusted until the ship's moving stages reach the target position of the first stage. In the second stage, the translation of the moving stages in the y-axis direction is adjusted, and finally the alignment of the moving stages is completed. The rotation of the moving stage around the x-axis can be achieved by the cooperative movement of the four trolleys in the y and z directions, similarly, the rotation of the moving stage around the y-axis can be achieved by the cooperative movement of the four trolleys in the x and z directions, the rotation of the moving stage around the z-axis can be achieved by the cooperative movement of the four trolleys in the x and y directions, and the translation of the ship's stage in the x, y, and z directions can be achieved by the four trolleys simultaneously translating in the x, y, and z directions. After determining the method for abutting the moving stage, the distance that the trolleys should move in each degree of freedom during stage abutting is calculated through inverse kinematics using the actual position of the trolleys before motion obtained in step S1 and the exact rotation matrix and exact translation matrix obtained in step S2, and finally, the trajectory is planned for the trolleys using a 5th-order polynomial fitting method to obtain the trolley motion plan trajectory.

[0034] The aforementioned ship movement stage trajectory planning uses a stepwise attitude adjustment method. In the first stage, the ship movement stage is rotated by an angle α around the x-direction to move it to a position horizontal to the x-axis, rotated by an angle β around the y-direction to move it to a position parallel to the y-axis, and rotated by an angle γ around the z-direction to move it to a position parallel to the z-axis, while simultaneously adjusting the translation amounts in the two degrees of freedom directions, x and z. In the second stage, the translation of the ship movement stage in the y-direction is adjusted. Based on the measured actual position of the trolley target ball (i.e., the actual position of the trolley before movement) and the specific abutment method of the ship movement stage, the distance that the trolley should move in each of the three degrees of freedom is determined through inverse kinematics, and the trolley trajectory is further planned through a 5th-order polynomial fitting method. The two-stage abutment method of the ship movement stage avoids interference phenomena due to the presence of the stage pipe. After the trajectory planning is completed, the visualization function of the higher-level software determines whether the total movement stages interfere with each other during adjustment. If the total movement stages interfere, the trolley trajectory planning policy is changed by re-selecting different path points. If there is no interference, it is determined that the specific trolley trajectory is the trolley trajectory currently calculated through the fifth-order polynomial fitting method, and finally the PLC controls the trolley motion. By determining the trolley trajectory through the fifth-order polynomial fitting method, the trolley speed and acceleration are made smoother, avoiding problems such as errors due to sudden changes in acceleration and motor damage.

[0035] In S4, after determining the trolley motion plan trajectory assuming that the moving stages do not interfere with each other, predictive compensation is performed for errors due to deformation of the bottom plate members of the moving stages, and the above errors are compensated by adjusting the difference in trolley movement distance and motion trajectory. Since the mass of different moving stages is different, when the trolley supports the bottom of the moving stages, moving stages of different weights result in different degrees of deformation of the ship bottom and trolley. Differences in the acceleration and velocity adjusted by the trolley result in slight deformation of the supported parts during adjustment of the moving stages, and compensation for the amount of deformation is realized through a BP neural network. Part 1: By controlling the speed and acceleration to be adjusted, the assembly environment, and the material of the bottom plate members of the moving stages, deformation data of the bottom plate members of the moving stages due to ship moving stages of different weights is measured, recorded, and mass-trained. In step 2, deformation data of the bottom plate member of the moving total stage provided by different types of total stages is measured, recorded, and extensively trained. Furthermore, errors due to deformation of the bottom plate member of the moving total stage of ships of various shapes under different elements are determined. The distance that the trolley should compensate for to compensate for the deformation of the moving total stage plate member is output by a neural network. The errors due to deformation of the bottom plate member of the moving total stage of the ship are compensated by adjusting the actual motion trajectory of the trolley. A BP neural network consisting of one input layer, three implicit layers, and one output layer is trained using historical data. Through training predictions, error values ​​due to deformation under different velocities, different accelerations, and different weights are obtained under the same policy, thereby compensating for the amount of movement of each degree of freedom of the trolley before adjusting the trolley motion. The trolley motion trajectory in step S3 is recalculated, and the compensated path matching trajectory is obtained.

[0036] Specifically, a BP neural network is used to predict the butt error due to deformation of the plate members of the moving total stages of ships of various shapes under the same acceleration, same velocity, and different weights. Under conditions where the environment is the same, the velocity and acceleration are the same, and the trolley supports the total stages at the same position, the control variable is the weight of the moving total stages of the ship. By extracting field data, the butt error due to the deformation of the bottom plate members caused by moving total stages of different weights is predicted. The higher-level software calculates the error, obtains compensation amounts in the three degrees of freedom directions of each trolley, and adds adjustment values ​​to the compensation amounts during the process of controlling the trolley motion, thereby reducing the number of butts and improving the efficiency of the ship's total stages butt. Similarly, the weight of the moving total stages of the ship, the trolley position, and the assembly environment are controlled to be constant, thereby predicting the total stage butt deviation under different accelerations and different velocities, and the higher-level software compensates for the three degrees of freedom motion values ​​of each trolley during the process of controlling the trolley motion. This error compensation system includes a BP neural network input layer, a BP neural network implicit layer, and a BP neural network output layer. The input layer includes five neurons for selecting weight, velocity, acceleration, displacement, and material properties. The implicit layer is configured in three layers and includes multiple neurons. The output layer has one neuron, which is the displacement compensation amount for each direction of each trolley.

[0037] In S5, finally, during adjustment control, the second laser tracker is used to measure the trolley target ball in the three degrees of freedom direction of each trolley, and at the same time, the laser rangefinder is used to measure the travel distance in the three degrees of freedom direction of each trolley. After the two devices have taken measurements, the measured data is processed to provide real-time feedback and control of the trolley's adjustment state until the actual adjustment of the trolley matches the target adjustment data, that is, until the actual path matching trajectory of the trolley matches the path matching trajectory compensated in step S4.

[0038] Specifically, during the trolley's movement, the laser rangefinder measures the trolley's movement distance in the three-degree-of-freedom plane in real time. After the moving stage completes the first stage adjustment, the adjustment process is paused, and the third and fourth laser trackers on the stage measure the trolley target balls located on the three moving planes of the four adjustable trolleys. This data is then fused with the data measured by the laser rangefinder, the average value is taken to ensure data accuracy, and this is compared to the distance the trolley should theoretically move. This difference is added to the second stage adjustment process of the moving stage and further fed back into the trolley's moving position. The moving stage then rotates around the x, y, and z axes and adjusts to translate in the x and z directions. It is determined whether the two stages have reached the target position of the first stage. If not, the moving stage rotates around the x, y, and z axes and readjusts to translate in the x and z directions until the two stages reach the target position of the first stage. If so, the moving stage adjusts to translate in the y direction.

[0039] The trolley is controlled using a PLC, and because the ship's movement phase is large, has high inertia, and demands high alignment, target balls are placed at target positions in each degree of freedom adjustment direction, and the target balls in each degree of freedom direction of the trolley are measured using a laser tracker. Laser rangefinders are placed in each degree of freedom direction of the trolley to measure the distance traveled in each degree of freedom, and the data measured by the laser tracker and the data measured by the laser rangefinders are processed and the average value of both data is taken to reduce the measurement error of a single measurement system, and the distance that the trolley should theoretically travel, determined in S4, is matched with the error value between the actual movement distance of the trolley and the theoretical distance, and feedback guidance is provided for the movement of the trolley. The laser tracker measures when a certain trolley target ball is obscured, and the data measured by the laser rangefinder is used to supplement it, preventing the loss of measured data, strengthening the robustness of acquiring trolley motion feedback guidance data, and providing data feedback and guidance for each degree of freedom stroke that has not moved to the target position.

[0040] While laser trackers offer high accuracy, they may be susceptible to shielding during measurement. In cases where measuring a particular trolley target is difficult, data measured by a laser rangefinder is used to supplement the data and ensure its integrity. Furthermore, in the event of a power outage or malfunction in the trolley, the trolley feedback measuring device can record its current position. The higher-level unit then stores and calculates based on this recorded data. After restoring power to the trolley or resolving the malfunction, it continues to control, adjust, and detect the trolley's motion until the total stage alignment is complete, achieving high accuracy and automatic alignment of the total stages.

[0041] Using a laser rangefinder and laser tracker, coordinated measurement and feedback are provided for the trolley's movement in all directions, ensuring accurate data feedback and recording even under conditions such as shielding, power outages, and malfunctions, and providing good robustness.

[0042] The present invention provides a high-precision measurement and automatic matching system suitable for the tight total stage of a ship, A data collection and processing module for locating a measuring device based on a set common reference point, calculating the position of the measuring device in a global coordinate system, measuring the coordinates of each key point target ball on the fixed and movable total step abutment surfaces using the measuring device, simultaneously measuring the three-degree-of-freedom moving plane position coordinates of the trolley, and converting both the coordinates of each key point and the three-degree-of-freedom moving plane position coordinates of the trolley into a global coordinate system using singular value decomposition (SVD). Using each key point of the moving stage as its center, draw a circle with a predetermined distance as the radius, calculate the weight of each key point of the moving stage based on the number of pipes in each circle, sort the key points of the moving stage in ascending order of weight, select any three key points that have the maximum weight and are not collinear, form a plane, find the center of mass of this plane, and, based on the principle of random combinations, select any three key points other than the above pair that have the maximum sum of weights and are not collinear, form a plane, find the center of mass of this plane, and so on, sequentially find the center of mass corresponding to the key points of the moving stage, and follow the same method to find the key points on the fixed stage. The corresponding center of mass is determined, three corresponding pairs of center of mass on the moving and fixed sections are selected using the three-point alignment method, the moving and fixed sections are established based on the selected three corresponding pairs of center of mass on the moving and fixed sections, the moving and fixed sections are calculated, the initial rotation matrix and initial translation matrix are determined, a rough alignment between the moving and fixed sections is achieved, the initial rotation matrix and initial translation matrix are substituted into the iterative nearest-neighbor ICP algorithm, the exact rotation matrix and exact translation matrix are determined, and a rough and exact alignment module is established to achieve exact alignment. The trolley's position relative to the total moving stage is determined, and the method of matching the total moving stage includes two stages: in the first stage, the displacement of the three degrees of freedom of the total moving stage in the x, y, and z directions and the rotation direction around the x and z axes are adjusted; in the second stage, the displacement of the total moving stage in the y direction is adjusted; and based on the acquired three-degree-of-freedom moving plane position coordinates of the trolley in the global coordinate system, and the obtained accurate rotation matrix and accurate translation matrix, the distance the trolley should move in each degree of freedom is determined through inverse kinematics; and a path matching trajectory planning module performs a path matching trajectory plan on the trolley using a 5th-order polynomial fitting method based on this distance data. A deformation compensation module is used to predict errors caused by deformation of the bottom plate member of the moving stage at the connection point between the trolley and the moving stage during path matching adjustment using a BP neural network, to train a BP neural network consisting of one input layer, three implicit layers, and one output layer using historical data, to obtain error values ​​for deformation due to different velocities, different accelerations, and different weights under the same policy through training predictions, thereby compensating for the amount of movement of each degree of freedom of the trolley during trolley path matching adjustment, and to obtain the path matching trajectory after deformation compensation. When controlling and adjusting the trolley, the system includes a motion feedback module that uses a measuring device to measure the coordinates of the trolley target ball in each of the three degrees of freedom until the actual path alignment trajectory of the trolley matches the path alignment trajectory after deformation compensation, simultaneously measures the planar distance that each trolley moves in each of the three degrees of freedom using the measuring device, and fuses the target ball coordinates in each of the three degrees of freedom and the travel distance data for each trolley in each of the three degrees of freedom measured by the measuring device to provide real-time feedback on the adjustment status of the trolley.

[0043] The measuring device includes a first laser tracker, a second laser tracker, and a laser rangefinder. Target balls are attached to key point locations and to the three-degree-of-freedom movement planes of the trolley, including the bottom, middle, and top surfaces of the trolley. The first laser tracker is used to measure the target ball coordinates at each key point, the second laser tracker is used to measure the trolley target ball coordinates on the trolley, and the laser rangefinder is used to measure the planar movement distance in the three-degree-of-freedom direction of each trolley. The number of first laser trackers ensures that all critical point target balls can be measured, and the position of each first laser tracker ensures that the most critical point target balls can be measured. The number of second laser trackers ensures that the target ball can be measured on the three-degree-of-freedom movement plane of all trolleys, and the position of each second laser tracker ensures that the target ball can be measured on the three-degree-of-freedom movement plane of the most numerous trolleys.

[0044] The present invention relates to an apparatus and equipment, Memory for storing computer programs that can be executed on the processor, When the computer program is running, it includes a processor for performing steps of a high-precision measurement and automatic matching method adapted to the tight margins of the vessel.

Claims

1. A method for high-precision measurement and automatic alignment of the outer circumferences of a first ship block and a second ship block, Step S1 involves fixing the first ship block in place and placing the second ship block on an adjustable trolley, establishing common reference points on the ground on both sides of the first and second ship blocks, establishing corresponding important points on the abutting surfaces of the first and second ship blocks, attaching a measuring device including a first laser tracker, a second laser tracker, and a laser rangefinder, locating the measuring device using the common reference points, calculating the position of the measuring device in a global coordinate system, measuring the coordinates of each important point using the first laser tracker, measuring the three-degree-of-freedom movable plane position coordinates of the trolley using the second laser tracker, and converting both the coordinates of each important point and the three-degree-of-freedom movable plane position coordinates of the trolley into a global coordinate system. Step S2 involves roughly matching the first ship block and the second ship block, obtaining an initial rotation matrix and initial translation matrix of the important point set of the abutting surfaces of the first ship block and the second ship block, and further obtaining an accurate rotation matrix and accurate translation matrix using an iterative nearest neighbor ICP algorithm, wherein each important point of the second ship block is used as the center of a circle, a circle is drawn with a predetermined distance as the radius, the weight of each important point of the second ship block is calculated based on the number of pipes in each circle, three important points with the maximum sum of weights and that are not collinear are selected to form a plane, the center of mass of this plane is found, and three important points other than the above one set of combinations have the maximum sum of weights and that are not collinear are selected Step S2 includes selecting a plane, determining the center of mass of this plane, sequentially determining the centers of mass corresponding to important points on the second ship block in this manner, determining the centers of mass corresponding to important points on the first ship block in the same manner, selecting three pairs of mutually corresponding and non-collinear centers of mass on the first ship block and the second ship block, establishing the second ship block abutting plane coordinate system and the first ship block abutting plane coordinate system through the three-point alignment method, calculating the two coordinate systems, determining the initial rotation matrix and initial translation matrix, achieving a rough fit between the second ship block and the first ship block, and substituting the initial rotation matrix and initial translation matrix into the iterative nearest neighbor ICP algorithm to determine the exact rotation matrix and exact translation matrix. Step S3 involves determining a second ship block abutting method, which includes two stages: in the first stage, adjusting the displacement of the second ship block in the x, y, and z directions and the rotation direction around the x and z axes in the three degrees of freedom; in the second stage, adjusting the displacement of the second ship block in the y direction; determining the position of the trolley relative to the second ship block based on the three-degree-of-freedom moving plane position coordinates of the trolley in the global coordinate system obtained in step S1; determining the distance the trolley should move in each degree of freedom through inverse kinematics by combining the accurate rotation matrix and accurate translation matrix obtained in step S2; and performing a path abutting trajectory plan on the trolley through a 5th-order polynomial fitting method to obtain the trolley motion plan trajectory. Step S4 involves using a BP neural network to predict errors due to deformation occurring at the connection point between the trolley and the second ship block during path matching adjustment, training a BP neural network including one input layer, three implicit layers, and one output layer using historical data, obtaining error values ​​due to deformation of the bottom plate member of the second ship block under different velocities, different accelerations, and different weights under the same policy through training predictions, thereby compensating for the distance the trolley should move in each degree of freedom obtained in step S3 during trolley path matching adjustment, and recalculating the trolley motion plan trajectory in step S3 to obtain the compensated path matching trajectory, A first ship block and a method for high-precision measurement and automatic alignment of the outer perimeters of a second ship block, characterized in that when controlling and adjusting the trolley, the second laser tracker measures the coordinates of the trolley target ball for each trolley until the actual path alignment trajectory of the trolley matches the path alignment trajectory compensated in step S4, and at the same time, the laser rangefinder measures the distance traveled by each trolley in the three degrees of freedom directions, and the data measured by the second laser tracker and the laser rangefinder are fused and the adjustment status of the trolley is fed back in real time.

2. In step S1, target balls are attached to each important point position and to the three-degree-of-freedom movement plane of the trolley, including the bottom surface, middle surface, and top surface of the trolley. The first laser tracker is used to measure the coordinates of the target balls on each important point, and the second laser tracker is used to measure the coordinates of the trolley target balls on each degree-of-freedom movement plane of the trolley. The number of first laser trackers ensures that all key point target balls can be measured, and the position of each first laser tracker ensures that all key point target balls can be measured. The method for high-precision measurement and automatic alignment of the outer perimeters of the first ship block and the second ship block according to claim 1, characterized in that the number of second laser trackers ensures that the target ball on the three-degree-of-freedom moving plane of all trolleys can be measured, and the position of each second laser tracker ensures that the target ball on the three-degree-of-freedom moving plane of the trolleys can be measured.

3. The specific method for rough matching in step S2 is as follows: (101) Calculate the weight of each important point on the second ship block, draw a circle with each important point as the center and a radius of half the width of the ship's total deck, and calculate the weight w of the i-th important point on the second ship block. １ The following applies: [Number 29] However, M is the total number of second ship block pipes, and N １ This is a circle R with the i-th important point on the second ship block as its center. １ The number of pipes at the center of the pipe circle included in the second ship block is given by W = {w1, ..., w}, where i is the number of the i-th important point on the second ship block, and the weight set of all important points on the second ship block is given by W = {w1, ..., w} Ｎ } and N is the total number of important points on the second ship block, (102) A set of weights W = {w1, ..., w} for all important points on the second ship block. Ｎ First, select three important points that have the maximum sum of weights and are not collinear, connect the three points in pairs to form a plane triangle, and calculate the triangle's center of mass g. １ Based on the principle of random combinations, we select three important points other than the above combinations that have the maximum sum of weights and are not collinear, connect the three points in pairs to form a plane triangle, and calculate the center of mass g of this triangle. ２ Similarly, following this method, the mass centers corresponding to three key points in all possible combinations of all key points on the second ship block. [Number 30] Calculate the following, where H is the number of sets of three important points that are selected as collinear: (103) The center of mass corresponding to a key point on the first ship block, according to the same method. [Number 31] Calculate the three non-collinear mass centers on the second ship block. [Number 32] and the three corresponding mass centers on the first ship block [Number 33] The method for high-precision measurement and automatic alignment of the outer circumferences of the first ship block and the second ship block according to claim 1, characterized in that a three-point alignment method is used to perform butt alignment and achieve rough alignment between the second ship block and the first ship block.

4. The method for calculating the exact rotation matrix and exact translation matrix in step S2 is as follows: (201) Establish the second ship block butt plane coordinate system and the first ship block butt plane coordinate system, g ｊ Taking the point as the coordinate origin, with the vector from g ｊ to g ｋ as the x-axis, construct unit vectors, [Number 34] And g ｊ from g ｌ The y-axis is determined by multiplying the direction vector and the x-axis vector, and the y-axis unit vector is constructed. [Number 35] Finally, e １ and e ２ The z-axis direction is determined using the power of , and its unit vector is as follows: e ３ =e １ ×e ２ The coordinate system of the second ship block butt joint surface is O ｇ -e １ , e ２ , e ３ And, Similarly, the coordinate system of the first ship block butt surface is determined. [Number 36] And, (202) Calculate the initial rotation matrix and the initial translation matrix, By aligning the measured data using the three-point alignment method, the initial rotation transformation matrix R of the set of important points on the second ship block abutting surface and the first ship block abutting surface is obtained. ０ It can be expressed as follows: [Number 37] Initial rotation matrix R ０ Based on this, the initial parallel sequence t ０ Calculate as follows: [Number 38] (203) Initial rotation matrix R ０ and the initial translation matrix t ０ The method for high-precision measurement and automatic alignment of the outer perimeters of a first ship block and a second ship block according to claim 3, characterized in that the values ​​are substituted into an iterative nearest-neighbor ICP algorithm, and the exact rotation matrix R and the exact translation matrix t are obtained by iterative calculation.

5. The trajectory plan for the second vessel block path alignment in step S3 uses a stepwise attitude adjustment method, specifically as follows: (31) The second ship block is rotated by an angle α around the x-direction to move the second ship block to a position horizontal to the x-axis, rotated by an angle β around the y-direction to move the second ship block to a position parallel to the y-axis, and rotated by an angle γ around the z-direction to move the second ship block to a position parallel to the z-axis, and the amount of translation in the two degrees of freedom directions x and z is adjusted simultaneously. (32) When the distance between the second ship block and the first ship block reaches a predetermined distance threshold, the translation in the y direction is adjusted to avoid interference during the adjustment of the second ship block due to the presence of the total stage pipe, and the trolley path abutment trajectory is planned through a fifth-order polynomial trajectory method, characterized in that a high-precision measurement and automatic abutment method of the outer circumferences of the first ship block and the second ship block according to claim 1.

6. Step S4 is specifically as follows: (41) Using a BP neural network, predict the butt joint error due to deformation of the plate members of the second ship block of various shapes of ships under the same acceleration, same velocity and different weights, under the conditions that the assembly environment is the same, the velocity and acceleration are the same, and the positions where the trolley supports the total stage are the same, the control variable is the weight of the second ship block, and by extracting field data, predict the butt joint error for the second ship block of different weights, calculate the butt joint error, obtain compensation amounts in the three degrees of freedom directions of each trolley, add the compensation amounts to the trolley path butt joint trajectory planned in step S3, and adjust the trolley path butt joint trajectory. (42) The method for high-precision measurement and automatic butting of the outer perimeters of the first ship block and the second ship block according to claim 1, characterized in that the weight of the second ship block, the trolley position and the assembly environment are controlled to be constant, thereby predicting the total butt deviation under different accelerations and different velocities, compensating for the three-degree-of-freedom motion trajectory of each trolley, the BP neural network input layer includes five neurons for selecting weight, velocity, acceleration, displacement and material properties, the implicit layer is set up in three layers and includes multiple neurons, and the output layer is provided with one neuron which is the displacement compensation amount in each direction of each trolley.

7. Step S5 is specifically as follows: The method for high-precision measurement and automatic alignment of the outer perimeters of a first ship block and a second ship block, as described in claim 1, is characterized in that the second laser tracker measures a trolley target ball placed on the three-degree-of-freedom movement plane of the trolley, simultaneously measures the three-degree-of-freedom motion of the trolley using a laser rangefinder, and fuses the data measured by the second laser tracker and the laser rangefinder, and when the second laser tracker measures that a certain trolley target ball is being obscured, the laser rangefinder replenishes the data, and when the trolley's power is cut off and a malfunction occurs, the trolley feedback measuring device records the trolley's current position, and when the trolley is energized or a contact failure occurs, it continues to control the trolley path alignment trajectory until the alignment of the second ship block and the first ship block is completed.

8. A high-precision measurement and automatic alignment system for the outer circumferences of a first ship block and a second ship block, A data collection and processing module for positioning a measuring device based on a set common reference point, calculating the position of the measuring device in a global coordinate system, measuring the coordinates of key point target balls on the abutting surfaces of the first and second ship blocks using the measuring device, simultaneously measuring the three-degree-of-freedom moving plane position coordinates of the trolley, and converting both the coordinates of the key points and the three-degree-of-freedom moving plane position coordinates of the trolley into a global coordinate system using singular value decomposition (SVD). Using each key point of the second ship block as its center, draw a circle with a predetermined distance as the radius, calculate the weight of each key point of the second ship block based on the number of pipes in each circle, rearrange the key points of the second ship block in ascending order of weight, select any three key points that have the maximum weight and are not collinear, form a plane, find the center of mass of this plane, select three key points other than the above pair of combinations that have the maximum sum of weights and are not collinear, form a plane, find the center of mass of this plane, sequentially find the centers of mass corresponding to the key points of the second ship block in this manner, find the centers of mass corresponding to the key points on the first ship block using the same method, and three points Through an alignment method, three pairs of corresponding mass centers on the second ship block and the first ship block are selected; based on the selected three pairs of corresponding mass centers on the second ship block and the first ship block, the abutting plane coordinate system of the second ship block and the abutting plane coordinate system of the first ship block are established, respectively; the abutting plane coordinate system of the second ship block and the abutting plane coordinate system of the first ship block are calculated; an initial rotation matrix and an initial translation matrix are obtained; a rough alignment between the second ship block and the first ship block is achieved; the initial rotation matrix and initial translation matrix are substituted into an iterative nearest-neighbor ICP algorithm to obtain an accurate rotation matrix and an accurate translation matrix; and a rough alignment and accurate alignment module is provided to achieve accurate alignment. The position of the trolley relative to the second ship block is determined, and the second ship block abutment method includes two stages: in the first stage, the displacement of the second ship block in the x, y, and z directions and the rotation direction around the x and z axes are adjusted; in the second stage, the displacement of the second ship block in the y direction is adjusted; and based on the acquired three-degree-of-freedom moving plane position coordinates of the trolley in the global coordinate system, and the obtained accurate rotation matrix and accurate translation matrix, the distance the trolley should move in each degree of freedom is determined by inverse kinematics, and a path abutment trajectory planning module performs a path abutment trajectory plan on the trolley using a 5th-order polynomial fitting method based on this distance data. A deformation compensation module is used to predict errors caused by deformation of the bottom plate member of the second ship block at the connection point between the trolley and the second ship block during path matching adjustment using a BP neural network, to train a BP neural network including one input layer, three implicit layers, and one output layer using historical data, to obtain error values ​​for deformation due to different velocities, different accelerations, and different weights under the same policy through training predictions, thereby compensating for the amount of movement of each degree of freedom of the trolley during trolley path matching adjustment, and to obtain the path matching trajectory after deformation compensation. A first ship block and a high-precision measurement and automatic alignment system for the outer perimeters of a second ship block, characterized in that when controlling and adjusting the trolleys, a measuring device is used to measure the coordinates of the trolley target ball in the three degrees of freedom directions of each trolley until the actual path alignment trajectory of the trolley matches the path alignment trajectory after deformation compensation, and at the same time, a measuring device is used to measure the planar distance that each trolley moves in the three degrees of freedom directions, and the target ball coordinates in the three degrees of freedom directions of each trolley measured by the measuring device and the distance traveled in the three degrees of freedom directions of each trolley are fused together and the adjustment status of the trolley is fed back in real time.

9. The measuring device includes a first laser tracker, a second laser tracker, and a laser rangefinder. Target balls are attached to key point locations and to the three-degree-of-freedom movement planes of the trolley, including the bottom, middle, and top surfaces of the trolley. The first laser tracker is used to measure the target ball coordinates at each key point, the second laser tracker is used to measure the trolley target ball coordinates on the trolley, and the laser rangefinder is used to measure the planar movement distance in the three-degree-of-freedom direction of each trolley. The number of first laser trackers ensures that all key point target balls can be measured, and the position of each first laser tracker ensures that all key point target balls can be measured. The first ship block and the second ship block according to claim 8, characterized in that the number of second laser trackers ensures that the target ball on the three-degree-of-freedom moving plane of all trolleys can be measured, and the position of each second laser tracker ensures that the target ball on the three-degree-of-freedom moving plane of the trolleys can be measured.

10. Apparatus and equipment, Memory for storing computer programs that can be executed on the processor, The apparatus is characterized in that, when the computer program is running, it includes a first ship block according to any one of claims 1 to 7 and a processor for performing steps of high-precision measurement and automatic alignment of the outer perimeters of the second ship block.

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