A port data pre-simulation accurate correction method based on a static total group

Abstract

The application provides a port data pre-simulation accurate correction method based on a standing total group, adopts a proactive prediction and elimination mode of "measurement-simulation-pre-correction-precision assembly", obtains segmented real physical states through high-precision measurement, constructs a virtual twin in a digital space and simulates the whole process of the standing total group, accurately predicts the port docking deviation, and then generates executable accurate correction instructions, so that the optimization of the port form is completed before the actual physical assembly starts, and finally one-time accurate folding is realized under intelligent monitoring. The application realizes a leap in controllable precision, greatly improves construction efficiency, reduces skill-dependent costs, forms a traceable precision data chain, and reduces measurement difficulty.

Description

Technical Field

[0001] This invention belongs to the field of shipbuilding technology, specifically relating to a method for accurate correction of port data pre-simulation based on vertical assembly. Background Technology

[0002] In modern shipbuilding, modular assembly construction technology is widely adopted to improve the efficiency of dock (platform) assembly. For ultra-high side sections (whose height is significantly greater than its width), vertical assembly is often used due to site and hoisting limitations. However, this process faces severe challenges: First, the sections deform significantly under their own weight in the vertical state, and the spatial shape of their ports (dating faces) has unpredictable elastic deviations from the theoretical design model; second, when multiple sections are assembled, the cumulative errors between the ports can easily lead to misalignment and uneven gaps. The traditional passive cyclical operation of "hoisting-measuring-cutting-adjustment" is inefficient, relies on worker experience, and has unstable quality. Furthermore, the vertical assembly height of sections is extremely high, making the high-altitude placement of optical targets for measurement difficult and posing a high risk factor.

[0003] While existing technologies employ methods such as 3D scanning to detect overall assembly accuracy (e.g., publication number CN114313092A) or controlling segment fabrication accuracy through jig ground samples (e.g., publication number CN115195923A), none have effectively solved the core problem of "how to accurately predict and eliminate port docking deviations before vertical assembly." In other words, there is a lack of a systematic method that can accurately simulate the overall assembly state in a virtual environment before the actual contact of segments and generate executable pre-correction instructions accordingly. Summary of the Invention

[0004] To address the technical problems existing in the prior art, this invention provides a method for accurate correction of port data pre-simulation based on vertical group, comprising the following steps: Step 1: Establish a precise 3D digital model to provide a precise digital foundation for virtual simulation that fully corresponds to the physical entity; Step 2: Digital pre-simulation of the overall assembly port matching, rehearsing the entire assembly process in advance in the digital space; Step 3, the automatic generation and output of the port correction scheme, is the key to transforming analysis and prediction into correction instructions. Based on the in-depth analysis results of Step 2, a "port matching dynamic correction scheme" that directly drives the operation of field equipment is automatically calculated and generated through the built-in intelligent compensation algorithm. Step 4, Pre-execution of Pre-processing Based on the Solution, is the execution stage that precisely maps digital instructions to physical entities; Step 5: Real-time monitoring of the optical target pre-embedding and assembly process serves as a guarantee and verification loop for the final assembly, ensuring that the effect of the pre-correction is maintained during dynamic hoisting and welding.

[0005] Furthermore, step 1 specifically includes: Step 11: After the segmented structure is welded and in a free-supported state, use a high-precision 3D laser scanner to perform an all-round scan of the target segment; the scanning focus is concentrated on the port area to be connected, and the port outer plate curved surface, the end of the internal longitudinal / transverse frame, and the preset permanent precision control reference points need to be completely captured. Step 12: Import the collected point cloud data into the analysis software for point cloud denoising, stitching, and coordinate system unification; perform "best fit alignment" or "feature alignment based on reference points" between the processed point cloud and the original 3D design model. Step 13: Generate a "measured digital twin segmented model" that integrates theoretical geometric information and measured deviation information.

[0006] Furthermore, in step 11, when the segmented structure is welded and in a free-supported state, it is located on the segmented jig and special gantry frame, and the preset permanent precision control reference point is the intersection of the inspection line.

[0007] Furthermore, the point cloud processed in step 12 is compared with the original 3D design model. Not only is coordinate matching completed, but the actual manufacturing error of the segment and the self-weight elastic deformation field under the current support state are quantified and recorded through the chromatographic deviation diagram.

[0008] Furthermore, step 2 specifically includes: Step 21: Based on the "measured digital twin models" of each segment established above, import the measured models of two adjacent segments into a dedicated shipbuilding accuracy simulation software; Step 22: In the software environment, according to the overall assembly process requirements, digitally pre-connect all segments in the vertical assembly posture in the software virtual environment. Step 23: The software automatically performs "collision detection" and "gap analysis", automatically analyzing key data such as gap distribution, misalignment, and straightness deviation of each docking port under simulated conditions.

[0009] Furthermore, in step 3, the port matching dynamic correction scheme generates a set of three-dimensional spatial coordinate correction values ​​for each port to be cut, which can be directly converted into the drive code of the CNC cutting machine or generate a two-dimensional cutting guide diagram with precise dimension annotations.

[0010] Furthermore, step 4 specifically includes: Before the on-site assembly begins, the segments to be assembled are placed in the correction station, which is equipped with high-rigidity support and CNC cutting equipment. The operator retrieves the "port matching correction scheme" for the corresponding segment from the central server and loads it into the control system of the CNC cutting machine. The baseline was verified and corrected on-site at the port using laser projection or digital templates. The equipment is then started, and the CNC cutting head performs a "one-time contour cutting" along the edge of the port according to the program instructions.

[0011] Furthermore, step 4 also includes: after the cutting is completed, a total station is used to quickly re-measure the cut port to verify that its shape is consistent with the requirements of the plan.

[0012] Furthermore, step 5 specifically includes: During the segmented manufacturing completion stage, a special optical target for measurement is pre-embedded in the key structure inside the port. When performing vertical group positioning of the corrected segments, a total station is used to track the three-dimensional coordinates of these optical targets in real time. The data is fed back to the simulation software and compared with the pre-simulated ideal closure trajectory to achieve millimeter-level fine-tuning guidance until the closure requirements are met and welding is completed.

[0013] Furthermore, the measurement-specific optical target is a reflective target.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: A leap forward in precision controllability: Precision issues are identified and resolved in virtual space before actual assembly, avoiding repeated trial and error on site, and improving port docking precision from unstable control at the "centimeter level" to reliable control at the "millimeter level".

[0015] Construction efficiency is greatly improved: It eliminates a large amount of on-site measurement, marking, manual trimming and waiting time in traditional methods, and transforms the uncertain working hours on the critical path of the overall assembly into deterministic pre-operation, which can shorten the overall assembly cycle by more than 30%.

[0016] Reduce reliance on skills and costs: Transforming "skills" that rely on the experience of highly skilled workers into repeatable and traceable "digital process instructions" reduces over-reliance on personnel experience and reduces waste of materials and time caused by rework.

[0017] A traceable precision data chain is formed: digital models, simulation reports, correction plans and monitoring records are generated throughout the process, forming a complete "segmented precision archive", which provides valuable data assets for subsequent integration and construction of similar products.

[0018] Reduced measurement difficulty: The pre-embedded optical target for vertical assembly perfectly solves the problem of not being able to manually place the optical target for measurement in the ultra-high segments of vertical assembly. During the assembly stage, only the instrument needs to be set up to monitor the accuracy of the assembly process and to perform complete measurement of the entire segment after the assembly is completed. Attached Figure Description

[0019] Figure 1This is a schematic diagram of a measured digital twin segmentation model according to an embodiment of the present invention; Figure 2 This is a schematic diagram of port digitization pre-simulation according to an embodiment of the present invention; Figure 3 This is a schematic diagram of a port correction scheme according to an embodiment of the present invention; Figure 4 This is a schematic diagram of port modification according to a certain embodiment of the present invention; Figure 5 This is a schematic diagram of the optical target pre-embedding and guidance positioning in a certain embodiment of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0021] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0022] This application provides a method for precise correction based on port data pre-simulation of vertical assembly. The core of this method lies in overturning the traditional passive "assembly-measurement-correction" mode and instead adopting a proactive prediction and elimination mode of "measurement-simulation-pre-correction-fine assembly." Its technical principle is to obtain the true physical state of segments through high-precision measurement, construct a virtual twin in digital space, and simulate the entire vertical assembly process to accurately predict port docking deviations. This generates executable precise correction instructions, optimizing the port morphology before actual physical assembly begins, and ultimately achieving precise one-time assembly under intelligent monitoring. Specifically, this method is implemented through the following five interconnected and progressively executed steps: 1. Establishment of a 3D digital model with precision settings Reference Figure 1 This step aims to provide a precise digital basis for virtual simulation that fully corresponds to the physical entity.

[0023] 1) After the segmented structure is welded and in a free-supported state (usually located on a segmented jig or a dedicated gantry), use a high-precision 3D laser scanner to perform a full-range scan of the target segment. The scanning focus is on the port area to be connected, and the outer curved surface of the port, the ends of the internal longitudinal / transverse framework, and the preset permanent precision control reference points (such as the intersection of inspection lines) must be completely captured.

[0024] 2) Import the collected point cloud data into the analysis software for point cloud denoising, stitching, and coordinate system unification. The processed point cloud is then matched with the original 3D design model (CAD) using either "best fit alignment" or "feature alignment based on reference points." This comparison process not only completes coordinate matching but, more importantly, quantifies and records the actual manufacturing errors of each segment (such as cutting errors and welding shrinkage) and the self-weight elastic deformation field under the current support state through chromatographic deviation maps.

[0025] 3) Generate a "measured digital twin segmented model" that integrates theoretical geometric information and measured deviation information. This model file (usually containing surface and solid features) is the sole real data source for all subsequent simulation analyses, ensuring consistency between the virtual and physical worlds.

[0026] Taking the vertical assembly of a high side section (approximately 22 meters high and 3 meters wide) of a large multipurpose vessel as an example, the model clearly shows the approximately 8 mm end difference and 6 mm outer plate deformation caused by manufacturing deviations and the transfer of the port due to its own weight.

[0027] 2. Digital pre-simulation of port matching for vertical control group Reference Figure 2 This step is the central decision-making link of the entire method, and its goal is to "rehearse" the entire process of the group in advance in the digital space.

[0028] 1) Import the measured digital twin models of each segment established above into a dedicated shipbuilding accuracy simulation software.

[0029] 2) In the software environment, based on the overall assembly process requirements, all segments are digitally pre-assembled in the software virtual environment according to the vertical assembly posture (virtual assembly).

[0030] 3) The software automatically performs "collision detection" and "gap analysis", automatically analyzing key data such as gap distribution, misalignment, and straightness deviation of each docking port under simulated conditions.

[0031] The analysis results show that, after considering their respective deformations, the theoretical gap between the two ports in the central region is 8 mm, but the deviation at both ends reaches 15 mm, showing a clear wedge-shaped gap.

[0032] 3. Automatic generation and output of port correction schemes Reference Figure 3This step is crucial for transforming analysis and prediction into corrective instructions. The system doesn't simply generate a report showing "where the problem is," but rather, based on the in-depth analysis results from step 2, it automatically calculates and generates a "port matching dynamic correction scheme" that directly drives the operation of field equipment through a built-in intelligent compensation algorithm.

[0033] The core logic of this algorithm is to reverse-engineer the amount of material that needs to be removed or compensated for at each point on each segmented port, aiming to achieve an "ideal fit" in the virtual simulation. This scheme generates a set of three-dimensional spatial coordinate corrections for each port to be trimmed, which can be directly converted into CNC cutting machine drive code or generate a two-dimensional cutting guide with precise dimensional annotations. This scheme ensures that the shape of the trimmed port has been pre-compensated for self-weight deformation and adjacent segment errors, becoming a "smart port" specifically matched for this particular three-dimensional assembly.

[0034] 4. Preliminary precise correction execution based on the solution Reference Figure 4 This step involves precisely mapping digital instructions to the execution phase of the physical entity. Before the on-site assembly begins, the segment to be assembled is placed in the correction station, which is equipped with high-rigidity support and CNC cutting equipment. The operator retrieves the "port matching correction scheme" for the corresponding segment from the central server and loads it into the control system of the CNC cutting machine. The correction baseline is then verified on-site at the port using laser projection or a digital template. Subsequently, the equipment is started, and the CNC cutting head performs a "one-time contour cutting" along the edge of the port according to the scheme instructions.

[0035] This process achieved several key breakthroughs: First, trimming and beveling preparation were completed in one go, with the cutting trajectory already including the necessary welding beveling angles; second, accuracy was guaranteed by the equipment, avoiding the cumulative errors caused by manual marking and cutting; and third, efficiency was extremely high, transforming the traditional trimming operation, which was performed at critical moments in the overall assembly and had uncertain working hours, into a deterministic task that could be planned in advance and performed in parallel. After this step was completed, the segmented ports were no longer in their theoretical state, but rather "intelligent ports" pre-adapted to the deformation of the vertical assembly and the errors of adjacent segments.

[0036] After cutting, a total station is used to quickly re-measure the cut port to verify its shape and consistency with the plan requirements, ensuring that the conversion from digital to physical is accurate and that the shape of the cut port is completely consistent with the plan requirements.

[0037] 5. Real-time monitoring of the target pre-embedding and assembly process Reference Figure 5This step serves as a guarantee and verification loop for the final assembly, ensuring that the effect of the pre-assembly correction is maintained during dynamic hoisting and welding. As an auxiliary verification and fine-tuning guarantee, during the segment fabrication completion stage, dedicated measurement optical targets (reflective targets) are pre-embedded at key structural locations within the port. During the vertical assembly positioning of the corrected segments, a total station is used to track the three-dimensional coordinates of these optical targets in real time, feeding the data back to the simulation software for comparison with the pre-simulated ideal closure trajectory. This allows for millimeter-level fine-tuning guidance until the closure requirements are met, at which point welding is completed. For example, the software screen displays the real-time deviation vector between the current port position and the virtual simulated ideal closure position (displayed as X: +7mm, Y: -6mm, Z: +4mm). The attitude adjustment jacks are then used for fine-tuning. After approximately 15 minutes, all deviation values ​​enter the green qualified zone (within ±3mm), and locating welding and continuous welding are then performed to complete the high-precision assembly.

[0038] This invention moves the decision-making stage for precision control from the "central team on-site" to the "pre-central team," transforming "passive response to deviations" into "proactive prediction and elimination of deviations." Its core consists of four inseparable components: Real data base: A three-dimensional digital model with accurate state is established by obtaining a segmented port measured model with actual manufacturing errors and self-weight deformation through 3D scanning, which serves as the only real data source for all analyses; High-fidelity predictive simulation: Strictly simulates vertical working conditions in simulation software to accurately predict the six degrees of freedom deviations (gap, misalignment, torsion) of the port connection and detect all problems in advance; Analysis and prediction are transformed into corrective instructions: The core innovation lies in the system's ability to automatically generate a two-dimensional cutting guide with precise dimension annotations based on prediction deviations, thus transforming the problem into an executable and precise trimming instruction; Closed-loop verification: Innovatively, internal measurement targets are pre-embedded in the segmented horizontal stage, and the measured data is compared with the virtual "ideal trajectory" in real time when the whole assembly is in the vertical state to guide fine-tuning, forming a "prediction-execution-verification" closed loop.

[0039] In summary, these are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent changes and modifications made in accordance with the scope of the present invention and the contents of the specification are within the scope of the present invention.

Claims

1. A method for accurate correction of port data pre-simulation based on vertical group, characterized in that, Includes the following steps: Step 1: Establish a precise 3D digital model to provide a precise digital foundation for virtual simulation that fully corresponds to the physical entity; Step 2: Digital pre-simulation of the overall assembly port matching, rehearsing the entire assembly process in advance in the digital space; Step 3, the automatic generation and output of the port correction scheme, is the key to transforming analysis and prediction into correction instructions. Based on the in-depth analysis results of Step 2, a "port matching dynamic correction scheme" that directly drives the operation of field equipment is automatically calculated and generated through the built-in intelligent compensation algorithm. Step 4, Pre-execution of Pre-processing Based on the Solution, is the execution stage that precisely maps digital instructions to physical entities; Step 5: Real-time monitoring of the optical target pre-embedding and assembly process serves as a guarantee and verification loop for the final assembly, ensuring that the effect of the pre-correction is maintained during dynamic hoisting and welding.

2. The method according to claim 1, characterized in that, Step 1 specifically includes: Step 11: After the segmented structure is welded and in a free-supported state, use a high-precision 3D laser scanner to perform an all-round scan of the target segment; the scanning focus is concentrated on the port area to be connected, and the port outer plate curved surface, the end of the internal longitudinal / transverse frame, and the preset permanent precision control reference points need to be completely captured. Step 12: Import the collected point cloud data into the analysis software for point cloud denoising, stitching, and coordinate system unification; perform "best fit alignment" or "feature alignment based on reference points" between the processed point cloud and the original 3D design model. Step 13: Generate a "measured digital twin segmented model" that integrates theoretical geometric information and measured deviation information.

3. The method according to claim 2, characterized in that: In step 11, when the segmented structure is welded and in a free-supported state, it is located on the segmented jig and special gantry frame, and the preset permanent precision control reference point is the intersection of the inspection line.

4. The method according to claim 2, characterized in that: In step 12, the processed point cloud is compared with the original 3D design model. Not only is coordinate matching completed, but the actual manufacturing error of the segment and the self-weight elastic deformation field under the current support state are quantified and recorded through the chromatographic deviation diagram.

5. The method according to claim 2, characterized in that, Step 2 specifically includes: Step 21: Based on the "measured digital twin models" of each segment established above, import the measured models of two adjacent segments into a dedicated shipbuilding accuracy simulation software; Step 22: In the software environment, according to the overall assembly process requirements, digitally pre-connect all segments in the vertical assembly posture in the software virtual environment. Step 23: The software automatically performs "collision detection" and "gap analysis", automatically analyzing key data such as gap distribution, misalignment, and straightness deviation of each docking port under simulated conditions.

6. The method according to claim 5, characterized in that: In step 3, the port matching dynamic correction scheme generates a set of three-dimensional spatial coordinate correction values ​​for each port to be cut, which can be directly converted into the drive code of the CNC cutting machine or generate a two-dimensional cutting guide with precise dimension annotations.

7. The method according to claim 6, characterized in that, Step 4 specifically includes: Before the on-site assembly begins, the segments to be assembled are placed in the correction station, which is equipped with high-rigidity support and CNC cutting equipment. The operator retrieves the "port matching correction scheme" for the corresponding segment from the central server and loads it into the control system of the CNC cutting machine. The baseline was verified and corrected on-site at the port using laser projection or digital templates. The equipment is then started, and the CNC cutting head performs a "one-time contour cutting" along the edge of the port according to the program instructions.

8. The method according to claim 7, characterized in that, Step 4 also includes: After the cutting is completed, use a total station to quickly re-measure the cut port to verify that its shape is consistent with the requirements of the plan.

9. The method according to claim 7, characterized in that, Step 5 specifically includes: During the segmented manufacturing completion stage, a special optical target for measurement is pre-embedded in the key structure inside the port. When performing vertical group positioning of the corrected segments, a total station is used to track the three-dimensional coordinates of these optical targets in real time. The data is fed back to the simulation software and compared with the pre-simulated ideal closure trajectory to achieve millimeter-level fine-tuning guidance until the closure requirements are met and welding is completed.

10. The method according to claim 9, characterized in that: The measurement-specific optical target is a reflective target.

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