Multi-laser radar fusion ship loader non-blind area measurement system and method

Abstract

The invention provides a multi-laser radar fusion ship loader non-blind area measurement system and method, and relates to the field of laser radar measurement, and the system comprises a ship body, a multi-laser radar fusion measurement device, a ship loader, and a mechanical arm. The mechanical arm clamps the upper end of the multi-laser radar fusion measurement device; the mechanical arm is movably arranged on the ship loader, the moving route of the mechanical arm is from the bow to the stern of the ship body, and the mechanical arm is always located on the center line above the ship body. According to the invention, the two long-distance laser radars are longitudinally installed and equipped with the high-precision holder, and the holder rotates at a low speed and a small angle, so that dynamic splicing of scanning data is realized, accurate point cloud data can be rapidly acquired in a short time, the data acquisition efficiency and precision are greatly improved, and the data acquisition cost is reduced. Through the installation of two long-distance radars and the cooperation of the other two short-distance radars, the non-blind area type measurement of the ship body is realized.

Description

Technical Field

[0001] The present invention relates to the field of laser radar measurement, and in particular to a multi-laser radar fusion ship loader blind-zone-free measurement system and method. Background Art

[0002] Ship loaders are large-scale mechanical equipment used by ports to load bulk materials or general cargo onto ships. The accuracy and efficiency of their operations are directly related to the port's throughput and operating costs. Traditional ship loaders rely on manual experience and are difficult to meet the growing needs of modern ports. Early studies on visual measurement of ship loaders focused on simple material monitoring, using cameras to obtain the approximate accumulation of materials in the hopper or conveyor belt to assist operators in determining whether it is necessary to adjust the loading speed or perform equipment maintenance. The introduction of LiDAR visual measurement technology enables ship loaders to perceive the surrounding environment, material status, and ship position in real time, opening up new ways for automated and intelligent operations, and gradually expanding to ship position identification, precise material flow measurement, etc. However, existing LiDAR measurement methods still have the following defects:

[0003] The mechanism-driven 2D laser radar scanning and point cloud stitching method uses 2D laser radar combined with a mechanical drive mechanism to scan, obtain point cloud data from multiple angles, and stitch them into a complete hull model through a 3D reconstruction algorithm. This method has high flexibility, but its detection results are easily affected by objects such as chutes. At the same time, this method has a slow scanning speed and low resolution, and cannot meet the real-time requirements and precise positioning requirements of dynamic operations of ship loaders.

[0004] The horizontal installation of long-range laser radars uses horizontal long-range laser radars to scan the hull from above and splice point cloud data, which has the advantages of large coverage and relatively simple installation. However, due to the obstruction of ship loader structures such as chutes and conveyor belt brackets, data on key parts such as the bow and stern are missing, and the upper scanning angle causes incomplete point cloud information of the open hatch material pile, affecting the measurement accuracy; in addition, the scanning speed of a single radar is limited, which is difficult to meet the needs of dynamic operations.

[0005] The multi-radar data stitching solution deploys multiple laser radars and uses data fusion algorithms to stitch the point clouds collected by each radar into a complete 3D model, which is suitable for use in the presence of occlusion. However, too many laser radars will also increase the complexity of the entire system and affect the stability of the system.

[0006] In summary, the three methods of mechanism-driven 2D LiDAR, horizontally mounted long-distance LiDAR, and multi-radar data stitching all have limitations. The above solutions are difficult to simultaneously address the following difficulties:

[0007] 1. Scanning speed: Ship loading operations are dynamic and continuous, requiring the laser radar measurement system to be highly real-time and to quickly feedback changes in ships and materials. However, some high-precision measurement methods, such as two-dimensional laser scanning and three-dimensional reconstruction technology, have slow scanning speeds and cannot keep up with the pace of ship loaders. Once the status of a ship or material changes, the measurement system data update lags behind, and it is difficult for operators to adjust strategies based on real-time data, resulting in low operating efficiency and prone to errors, affecting port efficiency.

[0008] 2. Measurement accuracy: The ship is long in the longitudinal direction, and the bow and stern are far from the loader's laser radar. Long-distance laser radar measurement is affected by energy attenuation and angular resolution, making it difficult to capture subtle structural changes at the bow and stern, and unable to achieve high-precision measurement of the ship's position and posture, which restricts the accuracy and refinement of loading operations.

[0009] 3. Chute obstruction: The ship loader has a complex structure, and components such as chutes and conveyor belt brackets often block the laser radar's line of sight, adding difficulties to measurement. Single laser radar lacks multi-angle information. When blocked, the key parts of the target are prone to "detection blind spots", resulting in incomplete measurement data and unable to reflect the actual status. When faced with complex obstructions, the combination of multiple laser radars will also cause data loss or increased errors in some areas, affecting the overall data quality and bringing difficulties to subsequent processing and analysis.

[0010] 4. Boom rotation: The rotation of the loader boom will significantly affect the viewing angle of the laser radar, and it is very likely to cause the hull to move out of the observation field of the laser radar. If the number of laser radars configured is too small, it is obviously difficult to achieve effective coverage of the entire ship; but if the number of laser radars is too large (more than 6), it will bring a heavy burden to the entire system, thereby affecting the stability of the system.

[0011] 5. Complex environment: The environment in which port operations are carried out is complex and changeable, and material dust permeates the air for years, which puts lidar visual measurement equipment under extremely severe challenges. Low-cost short-range lidar is particularly sensitive to dust, and dust particles will not only significantly weaken the intensity of the laser signal, but may also cause false triggering, causing a sharp drop in the stability and accuracy of its measurement. Summary of the invention

[0012] In view of this, the purpose of the present invention is to provide a multi-lidar fusion ship loader blind-spot measurement system and method, which is used to solve the problems of slow scanning speed, low measurement accuracy, chute obstruction, and the influence of boom rotation and complex environment on measurement accuracy in the existing lidar measurement method.

[0013] The present invention provides a multi-laser radar fusion ship loader blind spot measurement system, comprising:

[0014] The hull, multi-lidar fusion measurement device, ship loader and robotic arm;

[0015] The robotic arm clamps the upper end of the multi-lidar fusion measurement device;

[0016] The mechanical arm is movably arranged on the ship loader, and the moving route of the mechanical arm is from the bow to the stern of the hull, and is always located on the center line above the hull.

[0017] Preferred:

[0018] The multi-laser radar fusion measurement device includes: a first long-range laser radar, a second long-range laser radar, a first short-range laser radar, a second short-range laser radar, a first pan-tilt platform, a second pan-tilt platform, a slide barrel seat and a slide barrel;

[0019] The upper end of the chute is fixedly connected to the center position of the lower surface of the chute seat, and the upper surface of the chute seat is connected to the mechanical arm;

[0020] The first pan-tilt and the second pan-tilt are symmetrically arranged on the lower surface of the slide tube seat with the slide tube as the center, the first long-range laser radar is arranged on the first pan-tilt, and the second long-range laser radar is arranged on the second pan-tilt;

[0021] The first short-range laser radar and the second short-range laser radar are symmetrically arranged on the lower surface of the chute seat with the chute as the center;

[0022] The relative positions of the first short-range laser radar, the second short-range laser radar, the first gimbal and the second gimbal remain unchanged.

[0023] Preferred:

[0024] One of the first long-range laser radar and the second long-range laser radar is directed toward the shore side of the hull, and the other is directed toward the sea side of the hull.

[0025] Preferred:

[0026] One of the first short-range laser radar and the second short-range laser radar is directed toward the bow of the ship, and the other is directed toward the stern of the ship.

[0027] Preferred:

[0028] The rotation axes of the first long-range laser radar and the second long-range laser radar remain perpendicular to the direction from the bow to the stern of the hull.

[0029] Preferred:

[0030] The rotation axis directions of the first pan-tilt platform and the second pan-tilt platform are kept parallel to the direction from the bow to the stern of the hull;

[0031] The rotation axis direction of the first gimbal is perpendicular to the rotation axis of the first long-range laser radar, and the rotation axis direction of the second gimbal is perpendicular to the rotation axis of the second long-range laser radar.

[0032] Preferred:

[0033] When the multi-lidar fusion measuring device moves, the first gimbal controls the first long-range laser radar to rotate with the direction from the bow to the stern of the ship as the axis, and the second gimbal controls the second long-range laser radar to rotate with the direction from the bow to the stern of the ship as the axis, so that the first long-range laser radar and the second long-range laser radar move in a sinusoidal wave trajectory.

[0034] Preferred:

[0035] The rotation axes of the first short-range laser radar and the second short-range laser radar are directed vertically downward to the horizontal sea surface.

[0036] A multi-laser radar fusion ship loader blind spot measurement method is implemented based on the multi-laser radar fusion ship loader blind spot measurement system, comprising the steps of:

[0037] S1: Start the multi-laser radar fusion measurement device, make the multi-laser radar fusion measurement device move back and forth between the bow and the stern of the ship, and control the first long-range laser radar and the second long-range laser radar to move in a sinusoidal wave trajectory through the first pan-tilt and the second pan-tilt;

[0038] S2: Acquire the initial point cloud at the current moment through the first long-range laser radar, the second long-range laser radar, the first short-range laser radar and the second short-range laser radar;

[0039] S3: Obtain the rotation matrix and translation matrix of the multi-lidar fusion measurement device at the current moment, and construct the homogeneous transformation matrix at the current moment through the rotation matrix and translation matrix at the current moment;

[0040] S4: obtaining an updated point cloud at the current moment through calculation of the initial point cloud at the current moment and the homogeneous transformation matrix, and constructing a three-dimensional hull model at the current moment through the updated point cloud at the current moment;

[0041] S5: Repeat steps S2-S4 to update the 3D hull model in real time.

[0042] Preferred:

[0043] The expression of the updated point cloud at the current moment is: ΔT(θ i )·Pts i ;

[0044] Among them, i represents the current moment, Pts i represents the initial point cloud at the current moment, ΔT(θ i ) represents the homogeneous transformation matrix at the current moment, θ i Indicates the current PTZ rotation angle;

[0045]

[0046] Among them, R i Represents the rotation matrix at the current moment, t i Represents the translation matrix at the current moment.

[0047] The present invention has the following beneficial effects:

[0048] 1. Install two long-distance laser radars vertically and equip them with high-precision gimbals. By rotating the gimbals at a low speed and a small angle, the scanning data can be dynamically stitched together, and accurate point cloud data can be quickly obtained in a short time, greatly improving data collection efficiency and accuracy.

[0049] 2. Two short-range laser radars are added to scan the blind area around the chute that is difficult for long-range laser radars to reach, filling the data gap and ensuring all-round data collection without blind spots on the ship; and during the rotation of the boom, the scanning area can still stably cover the hull, ensuring the integrity and continuity of data collection;

[0050] 3. The four laser radars are all set on the lower surface of the slide seat, so that the scanning areas of the four laser radars are designed to overlap with a large area. This layout is conducive to high-precision splicing of long-range laser radar data in the later stage, further optimizing data quality, and making the final acquired ship posture information more accurate and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a structural diagram of a multi-lidar fusion measurement device;

[0052] Figure 2 This is a schematic diagram of long-distance laser radar scanning being blocked;

[0053] Figure 3 This is a bottom view of the multi-lidar fusion measurement device;

[0054] Figure 4 Schematic diagram of scanning the hull for multi-lidar fusion measurement device;

[0055] Figure 5 This is a schematic diagram of the pan / tilt movement;

[0056] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0057] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0058] The present invention provides a multi-laser radar fusion ship loader blind spot measurement system, comprising:

[0059] The hull, multi-lidar fusion measurement device, ship loader and robotic arm;

[0060] The robotic arm clamps the upper end of the multi-lidar fusion measurement device;

[0061] The mechanical arm is movably arranged on the ship loader, and the moving route of the mechanical arm is from the bow to the stern of the hull, and is always located on the center line above the hull.

[0062] As an example, a multi-laser radar fusion measurement device such as Figure 1 As shown:

[0063] The multi-laser radar fusion measurement device includes: a first long-range laser radar 1, a second long-range laser radar 2, a first short-range laser radar 3, a second short-range laser radar 4, a first pan-tilt platform 5, a second pan-tilt platform 6, a slide cylinder seat 7 and a slide cylinder 8;

[0064] The upper end of the chute 8 is fixedly connected to the center position of the lower surface of the chute seat 7, and the upper surface of the chute seat 7 is connected to the mechanical arm;

[0065] The first pan-tilt platform 5 and the second pan-tilt platform 6 are symmetrically arranged on the lower surface of the slide tube seat 7 with the slide tube 8 as the center, the first long-range laser radar 1 is arranged on the first pan-tilt platform 5, and the second long-range laser radar 2 is arranged on the second pan-tilt platform 6;

[0066] The first short-range laser radar 3 and the second short-range laser radar 4 are symmetrically arranged on the lower surface of the chute seat 7 with the chute 8 as the center;

[0067] The relative positions among the first short-range laser radar 3 , the second short-range laser radar 4 , the first gimbal 5 and the second gimbal 6 remain unchanged.

[0068] As an example:

[0069] One of the first long-range laser radar 1 and the second long-range laser radar 2 points to the shore side of the ship, and the other points to the sea side of the ship.

[0070] Specifically, the long-range laser radar is installed longitudinally, taking into account the characteristics of its scanning area being small near and large far away (the scanning area of ​​the long-range laser radar installed longitudinally has a significant characteristic: in the same horizontal plane, the range close to the radar end is narrow, and the range far away from the end is wide, showing a trend of small near and large far away, and the boundary of the area follows the change law of the quadratic curve. At the same time, with the gradual increase of the scanning distance, the resolution of the point cloud collected by the radar drops sharply, that is, the farther the distance, the more blurred the details presented in the point cloud, and the lower the accuracy), and its boundary shows the change law of the quadratic curve, so during the rotation of the boom, even if there are many variables, the scanning area can still steadily cover the hull.

[0071] As an example:

[0072] One of the first short-range laser radar 3 and the second short-range laser radar 4 points to the bow of the ship, and the other points to the stern of the ship.

[0073] As an example:

[0074] The rotation axes of the first long-range laser radar 1 and the second long-range laser radar 2 remain perpendicular to the direction from the bow to the stern of the hull.

[0075] Specifically, long-range laser radars must meet technical indicators, that is, the horizontal scanning coverage shall not be less than 180°, the vertical scanning interval shall not be narrower than 42°, the number of lines shall be at least 128, and the effective distance of ranging must exceed 180 meters. The installation requirements are as follows: When the rotating arm of the ship loader is driven so that the chute 8 is directly above the central axis of the reference ship type, the horizontal scanning direction of the long-range laser radar should be parallel to the axial direction from the bow to the stern, and its rotation axis direction should be perpendicular to the dock shore.

[0076] As an example:

[0077] The rotation axis direction of the first pan-tilt platform 5 and the second pan-tilt platform 6 is kept parallel to the direction from the bow to the stern of the hull;

[0078] The rotation axis direction of the first gimbal 5 is perpendicular to the rotation axis of the first long-range laser radar 1 , and the rotation axis direction of the second gimbal 6 is perpendicular to the rotation axis of the second long-range laser radar 2 .

[0079] Specifically, the base of each long-range laser radar needs to be separately and firmly installed on the corresponding high-precision one-degree-of-freedom rotating platform, and the platform is further reliably installed on the slide seat 7. The rotating platform has high-precision characteristics, and its rotation speed can be flexibly adjusted within the range of 0.1° to 1° / second, and the direction of the rotation axis is parallel to the direction from the bow to the stern, and is precisely perpendicular to the rotation axis of the long-range laser radar, ensuring that the long-range laser radar can be flexibly and accurately adjusted in azimuth.

[0080] As an example:

[0081] When the multi-lidar fusion measurement device moves, the first gimbal 5 controls the first long-range laser radar 1 to rotate with the direction from the bow to the stern of the ship as the axis, and the second gimbal 6 controls the second long-range laser radar 2 to rotate with the direction from the bow to the stern of the ship as the axis, so that the first long-range laser radar 1 and the second long-range laser radar 2 move in a sinusoidal wave trajectory.

[0082] As an example:

[0083] The rotation axes of the first short-range laser radar 3 and the second short-range laser radar 4 point vertically downward to the horizontal sea surface.

[0084] Specifically, there are two other short-range laser radars, which are also installed in a symmetrical manner on both sides of the chute 8, one facing the bow direction and the other corresponding to the stern direction. The two are relatively stationary with the chute seat 7 and do not need to be installed on a pan-tilt platform. The technical parameters of these two short-range laser radars are: the horizontal scanning range reaches 360° in all directions, the vertical scanning range is not less than 60°, and the ranging distance is not less than 50 meters. After the installation is completed, the rotation axis of the short-range laser radar points vertically downward to the horizontal ground, thereby ensuring that its detection angle of view can cover the surrounding environment in all directions and without blind spots, providing accurate and reliable monitoring data for the overall operation, thus avoiding the following problems. Figure 2 A single long-range lidar scan is shown with occlusion issues.

[0085] As an example:

[0086] The specific installation method of the first long-range laser radar 1, the second long-range laser radar 2, the first short-range laser radar 3, the second short-range laser radar 4, the first pan-tilt 5 and the second pan-tilt 6 is not unique. The first long-range laser radar 1, the second long-range laser radar 2, the first short-range laser radar 3 and the second short-range laser radar 4 can be stably fixed on the slide seat 7 according to the actual working conditions and meet the above-mentioned direction requirements. The bottom view of the multi-laser radar fusion measurement device is shown in FIG. Figure 3 As shown, the base of the first long-range laser radar 1 is fixed on the high-precision gimbal 5, and the high-precision gimbal 5 is fixed on the slide seat 7, and the two short-range laser radars are directly and stably fixed on the slide seat 7. The distances between the first long-range laser radar 1, the second long-range laser radar 2, the first short-range laser radar 3 and the second short-range laser radar 4 can be adjusted according to actual conditions to reduce the difficulty of installing each component.

[0087] The present invention provides a multi-laser radar fusion ship loader blind spot measurement method, which is based on the multi-laser radar fusion ship loader blind spot measurement system, and includes the following steps:

[0088] S1: Start the multi-laser radar fusion measurement device, so that the multi-laser radar fusion measurement device moves back and forth between the bow and the stern of the ship, and control the first long-range laser radar 1 and the second long-range laser radar 2 to move in a sinusoidal wave trajectory through the first pan-tilt platform 5 and the second pan-tilt platform 6;

[0089] Specifically, S11: chute positioning: move the chute of the ship loader to just above the empty ship, ensuring that the chute is aligned with the centerline of the hull;

[0090] S12: Radar start: Turn on the four laser radars (two long-range radars and two short-range radars) installed on the slide base and start preliminary scanning;

[0091] S13: Synchronization of the gimbal and lidar clocks: Control the gimbal to move along a sinusoidal curve trajectory, and simultaneously observe the position of the target object in the point cloud data collected by the lidar. Based on this position information, an algorithm is used to fit the curve of the target object's position changing over time. Then, the motion curve of the gimbal is compared and matched with the motion curve of the target object in the point cloud data, and key parameters such as the phase, frequency, and amplitude of the curve are fine-tuned. Through this process, the synchronization of the gimbal and lidar clocks is achieved, ensuring the coordination and unification of the two at the time level, laying a solid foundation for subsequent accurate data collection and analysis;

[0092] S2: Acquire the initial point cloud at the current moment through the first long-range laser radar 1, the second long-range laser radar 2, the first short-range laser radar 3 and the second short-range laser radar 4;

[0093] Specifically, S21: Basic point cloud generation: Four radars synchronously collect point cloud data of the hull and surrounding environment to generate a basic 3D model; since this is only based on a single viewpoint scan, some areas may be blocked by the chute or other structures, resulting in holes in the generated model;

[0094] S22: Dynamic scanning and stitching: Switch to the automatic operation mode, the system will automatically control the slide to move to the bow position, and then perform a series of detailed visual scans of the hull from the bow to the stern in an orderly manner;

[0095] S23: Pan / tilt motion control: During the scanning process, the system drives the high-precision pan / tilt mounted on the long-range laser radar to perform a small-angle (0.1°~1°) micro-motion according to the preset sine wave trajectory. This process takes only 1 second. During the pan / tilt motion, a series of single-frame point cloud data are continuously collected and stitched together in sequence to obtain accurate high-resolution point clouds, thereby improving the accuracy of the long-range laser radar.

[0096] S24: After the scanning is completed, the scan results of each part are spliced ​​and integrated to obtain an accurate and complete three-dimensional model. In this way, the entire hull can be modeled by completing the partially blocked area through the close-range radar, such as Figure 4 As shown in the figure, since the scanning viewpoints achieve all-round coverage and there is no visual blind spot, the constructed hull model will not have any holes;

[0097] S3: Obtain the rotation matrix and translation matrix of the multi-lidar fusion measurement device at the current moment, and construct the homogeneous transformation matrix at the current moment through the rotation matrix and translation matrix at the current moment;

[0098] Specifically, the gimbal and laser radar spatial calibration: First, set the initial angle θ0 of the gimbal and collect the corresponding initial point cloud Pts0. Then, drive the gimbal to a series of specific angles θ0 and synchronously collect a series of point cloud frames {Pts i}, where i = 1, 2, ..., N, and N is the number of sampling times, which is generally not less than 3. Then, the point cloud 3D alignment technology is used to obtain a point cloud that satisfies Pts i =ΔT(θ i )·Pts0 relationship. Here ΔT(θ i ) is a 4×4 homogeneous transformation matrix. Compared to θ i A function that can accurately describe the mathematical transformation relationship of the point cloud at different angles. Finally, the functional transformation relationship between θ and ΔT(θ) is derived through the difference algorithm. In this way, for any given θ value, the corresponding precise transformation matrix ΔT(θ) can be calculated based on the established transformation relationship, thereby providing support for subsequent accurate point cloud processing and related applications;

[0099] S4: obtaining an updated point cloud at the current moment through calculation of the initial point cloud at the current moment and the homogeneous transformation matrix, and constructing a three-dimensional hull model at the current moment through the updated point cloud at the current moment;

[0100] Specifically, the accuracy of long-range LiDAR can be improved by expanding the scanning coverage through micro-movement of the gimbal, combining sinusoidal trajectory fitting, and splicing data within 1 second to obtain a higher-precision point cloud. Figure 5 As shown in the figure, during the movement of the gimbal, each frame of point cloud Pts is collected i , then according to the point cloud timestamp and the gimbal timestamp, accurately find the gimbal rotation angle θ that best matches it i Next, calculate the corresponding 4×4 homogeneous transformation matrix ΔT(θ i ), use the transformation matrix to transform the current point cloud and get a new point cloud ΔT(θ i )·Pts i Finally, the transformed point clouds are stitched together to obtain a high-resolution point cloud.

[0101] S5: Repeat steps S2-S4 to update the 3D hull model in real time.

[0102] Specifically, in the actual process of loading, once there is a need to update the real-time status of the hull, the updated hull model can be immediately obtained to ensure that the dynamic changes in the hull position and the real-time status changes of the material volume can be accurately grasped, providing strong guarantees for the smooth progress of loading operations.

[0103] As an example:

[0104] The expression of the updated point cloud at the current moment is: ΔT(θ i )·Pts i ;

[0105] Among them, i represents the current moment, Pts i represents the initial point cloud at the current moment, ΔT(θ i ) represents the homogeneous transformation matrix at the current moment, θ i Indicates the current PTZ rotation angle;

[0106]

[0107] Among them, R i Represents the rotation matrix at the current moment, t i Represents the translation matrix at the current moment.

[0108] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0109] The serial numbers of the embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. In a unit claim that lists several means, several of these means may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order and these words may be interpreted as identifiers.

[0110] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A multi-laser radar fusion ship loader blind spot measurement system, characterized in that: include: The hull, multi-lidar fusion measurement device, ship loader and robotic arm; The robotic arm clamps the upper end of the multi-lidar fusion measurement device; The mechanical arm is movably arranged on the ship loader, and the moving route of the mechanical arm is from the bow to the stern of the hull, and is always located on the center line above the hull.

2. The multi-laser radar fusion ship loader blind spot measurement system according to claim 1 is characterized by: The multi-laser radar fusion measurement device comprises: a first long-range laser radar (1), a second long-range laser radar (2), a first short-range laser radar (3), a second short-range laser radar (4), a first pan-tilt platform (5), a second pan-tilt platform (6), a slide cylinder seat (7) and a slide cylinder (8); The upper end of the chute (8) is fixedly connected to the center position of the lower surface of the chute seat (7), and the upper surface of the chute seat (7) is connected to the mechanical arm; The first pan-tilt platform (5) and the second pan-tilt platform (6) are symmetrically arranged on the lower surface of the slide tube seat (7) with the slide tube (8) as the center, the first long-range laser radar (1) is arranged on the first pan-tilt platform (5), and the second long-range laser radar (2) is arranged on the second pan-tilt platform (6); The first short-range laser radar (3) and the second short-range laser radar (4) are symmetrically arranged on the lower surface of the chute seat (7) with the chute (8) as the center; The relative positions between the first short-range laser radar (3), the second short-range laser radar (4), the first pan-tilt platform (5) and the second pan-tilt platform (6) remain unchanged.

3. The multi-laser radar fusion ship loader blind spot measurement system according to claim 2 is characterized by: One of the first long-range laser radar (1) and the second long-range laser radar (2) points to the shore side of the ship, and the other points to the sea side of the ship.

4. The multi-laser radar fusion ship loader blind spot measurement system according to claim 2 is characterized by: One of the first short-range laser radar (3) and the second short-range laser radar (4) points to the bow of the ship, and the other points to the stern of the ship.

5. The multi-laser radar fusion ship loader blind spot measurement system according to claim 2 is characterized by: The rotation axes of the first long-range laser radar (1) and the second long-range laser radar (2) are kept perpendicular to the direction from the bow to the stern of the ship.

6. The multi-laser radar fusion ship loader blind spot measurement system according to claim 5 is characterized by: The rotation axis directions of the first pan-tilt platform (5) and the second pan-tilt platform (6) are kept parallel to the direction from the bow to the stern of the ship; The direction of the rotation axis of the first pan-tilt platform (5) is perpendicular to the rotation axis of the first long-range laser radar (1), and the direction of the rotation axis of the second pan-tilt platform (6) is perpendicular to the rotation axis of the second long-range laser radar (2).

7. The multi-laser radar fusion ship loader blind spot measurement system according to claim 6 is characterized by: When the multi-laser radar fusion measurement device moves, the first pan-tilt platform (5) controls the first long-range laser radar (1) to rotate with the direction from the bow to the stern of the ship as the axis, and the second pan-tilt platform (6) controls the second long-range laser radar (2) to rotate with the direction from the bow to the stern of the ship as the axis, so that the first long-range laser radar (1) and the second long-range laser radar (2) move along a sinusoidal wave trajectory.

8. The multi-laser radar fusion ship loader blind spot measurement system according to claim 2 is characterized by: The rotation axes of the first short-range laser radar (3) and the second short-range laser radar (4) are vertically downwardly pointed toward the horizontal sea surface.

9. A method for measuring a ship loader without blind spots by fusion of multiple laser radars, which is implemented based on the system for measuring a ship loader without blind spots by fusion of multiple laser radars according to any one of claims 1 to 8, and is characterized in that: Includes steps: S1: starting the multi-laser radar fusion measurement device, causing the multi-laser radar fusion measurement device to move back and forth between the bow and the stern of the ship, and controlling the first long-range laser radar (1) and the second long-range laser radar (2) to move in a sinusoidal wave trajectory through the first pan-tilt platform (5) and the second pan-tilt platform (6); S2: acquiring an initial point cloud at the current moment through the first long-range laser radar (1), the second long-range laser radar (2), the first short-range laser radar (3) and the second short-range laser radar (4); S3: Obtain the rotation matrix and translation matrix of the multi-lidar fusion measurement device at the current moment, and construct the homogeneous transformation matrix at the current moment through the rotation matrix and translation matrix at the current moment; S4: obtaining an updated point cloud at the current moment through calculation of the initial point cloud at the current moment and the homogeneous transformation matrix, and constructing a three-dimensional hull model at the current moment through the updated point cloud at the current moment; S5: Repeat steps S2-S4 to update the 3D hull model in real time.

10. The method for measuring a ship loader without blind spots by fusion of multiple laser radars according to claim 9 is characterized in that: The expression of the updated point cloud at the current moment is: ΔT(θ i )·Pts i ; Among them, i represents the current moment, Pts i represents the initial point cloud at the current moment, ΔT(θ i ) represents the homogeneous transformation matrix at the current moment, θ i Indicates the current PTZ rotation angle; Among them, R i Represents the rotation matrix at the current moment, t i Represents the translation matrix at the current moment.

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