CN121876830A - A method for measuring cargo hold dimensions of the MARK III cargo containment system - Google Patents
A method for measuring cargo hold dimensions of the MARK III cargo containment systemInfo
- Publication number
- CN121876830A CN121876830A CN202511887238.5A CN202511887238A CN121876830A CN 121876830 A CN121876830 A CN 121876830A CN 202511887238 A CN202511887238 A CN 202511887238A CN 121876830 A CN121876830 A CN 121876830A
- Authority
- CN
- China
- Prior art keywords
- cargo
- laser tracker
- measuring
- coordinates
- cargo hold
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Length Measuring Devices By Optical Means (AREA)
Abstract
一种MARKⅢ货物围护系统货舱尺寸测量方法，将货舱分为10个面，共计16个角点，在艏面和艉面的中心设置激光跟踪仪，在每个角点所对应的三个面内设置多个靶球，利用激光跟踪仪对角点所对应的三个面内的靶点进行探测，探测结束后，即可在polyworks软件中创建平面，角点所对应的三个平面创建完成后，三个平面相交形成的交点坐标即为当前角点的三维坐标，依次测量得到16个角点的三维坐标。将角点三维坐标输入EXCEL中，直接得到货舱线段和对角线的长度。本发明的这种方法使得测量次数减少，从原来的64次减少为16次，减少75%。人工工时减少，原方法需要20人测量2天，本方法需要5人测量1天，工时减少87.5%。提高了测量精度高，避免计算错误。
A method for measuring cargo hold dimensions in a MARK III cargo containment system involves dividing the cargo hold into 10 faces, totaling 16 corner points. A laser tracker is positioned at the center of the bow and stern faces. Multiple target spheres are placed within the three faces corresponding to each corner point. The laser tracker probes the target points within these three faces. After probing, planes are created in PolyWorks software. The coordinates of the intersection of these three planes are the 3D coordinates of the current corner point. This process is repeated to measure the 3D coordinates of all 16 corner points. The 3D coordinates are then input into Excel to directly obtain the lengths of cargo hold line segments and diagonals. This method reduces the number of measurements from 64 to 16, a 75% reduction. It also reduces manpower; the original method required 20 people for 2 days, while this method requires only 5 people for 1 day, a 87.5% reduction. Furthermore, it improves measurement accuracy and avoids calculation errors.
Description
Technical Field
The invention belongs to the field of construction and design of marine ships, and particularly relates to a method for measuring the size of a cargo hold of a MARKIII cargo containment system.
Background
The cargo hold of the LNG ship of the MARK III cargo containment system (hereinafter referred to as cargo containment), is octagon, and each cargo hold has 10 faces, A, B, C, D, E, F, G, H, J, K faces respectively, as shown in fig. 1.
One of the most important materials for cargo enclosure construction is an insulating plate, which is fixed on the bulkhead of the cargo compartment through nut studs and resin glue, wherein the studs are welded on the bulkhead in advance. In order to ensure that the stud is positioned accurately, the mounting positions of the insulating plates meet the tolerance, a grid line needs to be drawn on each bulkhead, and the insulating plates are mounted in the grid lines.
In order to ensure accurate scribing positions of grid lines, transverse and longitudinal two datum lines need to be scribed on each cabin surface in advance, and the datum lines are used as the datum lines when the grid lines are scribed, so that accumulated errors are avoided.
The main wall of the MARK III type cargo surrounding system is made of stainless steel corrugated plates, and the corrugations must be continuous and must be continuous on adjacent surfaces in order to ensure tightness of the main wall. The corrugated board score lines must also be continuous at adjacent faces. The corrugated plates are welded on the insulating plates, the corrugated plate lines are obtained by returning lines of grid lines of the insulating plates, so that the size of the whole cabin must be measured before the datum line of the insulating plates is drawn, and the continuity of the adjacent surface lines is ensured through integral consideration.
Depending on the process requirements, 24 side lengths and 40 diagonal lengths of the cargo hold need to be measured before the cargo hold is scored (see fig. 2, 3).
For the side length, a conventional measurement method is to measure the side lengths of 24 sides one by one using a laser range finder.
For diagonal, conventional measurement methods require the use of dedicated diagonal dimension measurement tools (see fig. 4). The tool is fan-shaped, the angle is matched with the included angle of the bulkhead, and the cargo hold of the conventional LNG ship has four angles of 90 degrees, 135 degrees, 108.4 degrees and 161.6 degrees respectively. Each group of tools is provided with 2 boxes (the distance measuring devices can move on the tools) with the laser distance measuring devices, one box is a diagonal target tool, and the distance a between the distance measuring devices and the circle center of the tool and the radius b of the target tool are fixed values. During measurement, two fan-shaped tools are placed diagonally, the tools are ensured to be contacted with three surfaces simultaneously, and the distance c between the range finder and the target tool is measured, so that the diagonal line length is a+b+c. 40 diagonal lengths were measured one by one.
The disadvantages of conventional cargo hold sizing are as follows:
(1) The number of measurement is too large, the single cabin needs to be measured 64 times, and the required manpower and period are long.
(2) The range finder has a larger tolerance at longer distances. According to field experience, the deviation measured by the distance meter can reach more than 10mm in the measuring range of 50m (the total length of the cargo hold is about 50 m). And the laser spots emitted by the range finder are blurred during long-distance measurement, so that the accuracy of the measurement position is difficult to determine.
(3) The diagonal measurement method has a large error. When the diagonal line is measured, certain errors exist in the precision of the tool, and certain errors can be generated because the bulkhead deformation tool cannot be clung to the bulkhead. Multiple errors are accumulated, so that the method has larger systematic errors.
(4) C faces the angle line and measures difficulty. The supporting legs of the installation platform (scaffold required for cargo enclosure construction) in the cargo cabin are located on the C face, laser can be blocked due to the fact that the number of the supporting legs is large, and the diagonal line of the C face is difficult to operate when the laser range finder is used for measuring.
Disclosure of Invention
In order to solve the problems, the invention provides a method for measuring the size of a cargo hold of a MARKIII cargo containment system, which aims to reduce the measurement times and ensure the accuracy of measurement data, and adopts the following technical scheme:
A method for measuring the size of cargo hold of MARKIII cargo enclosure system features that 10 sides are bow, stern, left, right, top, bottom, left and right sides, and three adjacent sides form a corner point for 16 corners.
S1, fixing a laser tracker at the center of a bow surface or a stern surface of a cargo compartment, arranging a plurality of target balls in three surfaces corresponding to each corner point, wherein the target balls are close to adjacent corner points, and the plurality of target balls are distributed and staggered up and down.
S2, using laser pens to irradiate target balls in the left side and the right side at the positions of a laser tracker of the bow surface and the stern surface simultaneously, observing whether laser can detect all the target balls in the left side and the right side simultaneously, and if the target balls cannot be detected somewhere, shifting the target balls to ensure that the target balls in the left side and the right side can be irradiated by the laser pens in two positions simultaneously.
S3, inputting the actual diameter of the target ball into polyworks operation software, detecting targets in three planes corresponding to the current corner point for the first time by using a laser tracker, lifting the target ball after the first detection is finished, detecting for the second time, and creating planes in polyworks software after the second detection is finished, wherein the intersection point coordinates formed by intersecting the three planes corresponding to the current corner point are the three-dimensional coordinates of the current corner point.
And (3) sequentially measuring to obtain three-dimensional coordinates of 16 corner points by adopting the method of the step (S3).
S4, calculating side length and diagonal line
Inputting three-dimensional coordinates of 16 corner points into an excel table, and calculating the distance between two points according to the formula =And obtaining the side length or diagonal line size corresponding to each corner point.
Wherein X1 and X2 are the X coordinates of two corner points.
Y1 and Y2 are Y coordinates of two corner points.
Z1 and Z2 are Z coordinates of two corner points.
And finally outputting the sizes of 24 side lengths and 40 diagonals of the cargo hold in an excel table.
And S5, checking the result, comparing the calculated side length and diagonal line size with the theoretical size, checking whether the calculated side length and diagonal line size are out of tolerance, retesting the data by a method of directly measuring by a disc ruler or a range finder if some data are out of tolerance, comparing the deviation of the calculated side length and diagonal line size with the measured data of the laser tracker, and acquiring the measured data of the laser tracker if the deviation is within a specified range.
In the method for measuring the size of the cargo hold of the MARKIII cargo containment system, a square frame is adhered to the center of the bow surface or the stern surface of the cargo hold by using a masking tape, and the laser tracker base is fixed to the bulkhead in the square frame through the base.
In the method for measuring the size of the cargo hold of the MARKIII cargo containment system, the target ball base is further fixed with the bulkhead through hot melt adhesive.
According to the cargo hold size measuring method of the MARKIII cargo containment system, further, the distance between the target ball and the adjacent corner point is 100-300 mm.
In the method for measuring the size of the cargo hold of the MARKIII cargo containment system, the laser tracker is fixed on the bulkhead through the base, and the thickness of the base and the height of the laser tracker are less than the distance between each layer of boundary of the mounting platform and the bulkhead.
In the method for measuring the size of the cargo hold of the MARKIII cargo containment system, with respect to step S3, the 8 corner points on one of the bow surface and the stern surface are measured first, and after the measurement is completed, the 8 corner points on the other surface are measured.
In the cargo hold size measurement method of MARKIII cargo containment system, further, in order to ensure that the data measured before and after the displacement of the laser tracker are unified in a coordinate system, after measuring 8 corner points on one surface, frog-leaping operation is required to be performed on polyworks software, and then 8 corner points on the other surface are measured.
The beneficial effects of the invention are as follows:
1. the measurement times are reduced from 64 times to 16 times, and 75 percent.
2. The labor hour is reduced, 20 people are required to measure for 2 days in the original method, 5 people are required to measure for 1 day in the method, and the labor hour is reduced by 87.5%.
3. The measuring precision is high, when the distance is measured in a cargo hold for a long distance (the maximum is about 60 m), the measuring error of the distance meter is more than 10mm, the error of the laser tracker is less than 1mm, and the precision is improved by 90%.
4. The method is recorded and calculated by a computer in the whole course, and errors caused by manual transcription are avoided.
5. The formula calculation is input through the excel worksheet, so that the method can be input once and used for multiple times, and meanwhile calculation errors are avoided.
Drawings
FIG. 1 is a diagram of a cargo compartment 10 panel profile.
Figure 2 is a schematic diagram of the diagonal of the cargo space that needs to be measured.
FIG. 3 is a schematic diagram of a diagonal line of a cargo tank to be measured.
Fig. 4 is a schematic diagram of a prior art measuring device.
Fig. 5 is a schematic diagram of a laser tracker and a target ball.
Fig. 6 is three planes adjacent to the detection corner.
Fig. 7 is a view showing that the off-hook deviation is large.
FIG. 8 is a schematic illustration of the EXCEL table calculation edge length.
Detailed Description
The invention will be described in detail with reference to specific embodiments.
As shown in fig. 6, a method for measuring the size of a cargo hold of a MARKIII cargo containment system, a laser tracker is a portable high-precision three-dimensional coordinate measuring device. It uses laser as measuring means, and is equipped with a laser emitting mechanism and a reflecting target ball (hereinafter referred to as target ball) which are rotated around two axes, see fig. 5. During measurement, the laser tracker emits laser to the center of the target ball, and a three-sided mirror is arranged in the target ball to reflect the laser to the laser tracker. The distance is determined by the laser reflection speed, the laser emission angle is determined by an angle encoder in the device, and the three-dimensional coordinates of the position of the target can be determined by combining the laser emission angle and the laser reflection speed. The method comprises the following specific steps:
S1, adsorbing a laser tracker on a D surface of a cargo hold through a laser tracker base
The laser tracker base mainly comprises an annular frame, a cross structure, a laser tracker connecting piece and a magnet assembly, wherein the thickness of the base is not too large, and the base thickness and the laser tracker height are less than the distance from each layer boundary of the mounting platform to the bulkhead.
The mounting platform is a scaffold for construction in the cargo hold, and a certain distance exists between the boundary of each layer of mounting platform and the bulkhead, so that the scaffold is a space required by cargo enclosure construction.
And S2, sticking a square frame near the center of the fore and aft surfaces (namely D, B surfaces) of the cargo hold by using a masking tape, adsorbing the laser tracker base onto a bulkhead in the square frame of the D surface of the cargo hold by using a magnet assembly, and then fixing the laser tracker to the laser tracker base by using a device connecting piece.
The position of the target ball base is determined, the target ball base is a base for bearing the target ball and consists of a cylindrical shell and a magnet, the top surface of the cylindrical shell is provided with a spherical groove, the groove is matched with the size of the target ball, the target ball base is adsorbed to a bulkhead through the magnet when in use, the target ball is placed in the groove of the cylindrical shell, and the target ball can be ensured to be fixed through the magnet.
And a plurality of target ball bases are respectively arranged on the F surface and the J surface, and the positions of the target ball bases are dispersed and staggered up and down. As a reference point of the transfer station of the laser tracker, the point measured before and after the movement of the laser tracker is ensured to be in a coordinate system.
And a laser pen is used beside the D-plane laser tracker to irradiate, so as to observe whether the laser can detect the target ball base on the F, J plane without being blocked by the upright post of the mounting platform. If a target ball base cannot be detected somewhere, the target ball base needs to be shifted. And the laser pen is synchronously used for irradiation at the B-plane square frame position, so that all fixed target seats can be detected by the laser pens at two positions at the same time.
After the position of the target ball base is determined, the target ball base is further firmly adhered to the bulkhead by using hot melt adhesive, so that the displacement of the target ball base caused by vibration of the ship body is prevented. The magnetic type is convenient to install, but cannot be fixed for a long time, and vibration/placement of the target ball on the ship body can cause displacement of the target ball base to affect accuracy, so that the hot melt adhesive is needed for fixing.
Starting up and detecting the laser tracker, opening the laser tracker according to the operation flow of the equipment, and correcting the precision. In the equipment operation software, polyworks operation software is adopted, and the diameter of the target ball is set to be consistent with the diameter of the actual target ball.
Taking the measurement corner CDK as an example:
the creation plane is selected in polyworks software, the creation mode being probing. And 5 target ball placement points are respectively arranged on three surfaces corresponding to the corner points of the surface D, and the distances between the points and the corner points are 100-300 mm as shown in fig. 6. The target ball is closely attached to the bulkhead and sequentially detected, after the detection is finished, the target ball is lifted, the detection is performed once again, and the detected plane is consistent with the D plane. According to the method, the C face and the K face are detected, 5 target balls are arranged on each face and are measured, and then the measurement of the angular point CDK can be completed.
The naming mode of the side in the cargo compartment is that the side is + the two sides where the side is located, the side of the D-plane is named as side DA, side DE, side DF and the like, the naming mode of the corner is that the corner is + the three sides where the corner is located, and the corner of the D-plane is named as corner ADE, corner CDK and the like.
In polyworks software, the detected D, C, K surface is selected, points are created in a way that three planes intersect, and then three-dimensional coordinates of the angular point CDK can be obtained.
The method of the installation step S3 sequentially detects 8 corner points of the D surface, and totally measures 24 facets and 120 points. And operating in polywork software to obtain three-dimensional coordinates of the 8 corner points, and extracting and outputting the three-dimensional coordinates of the 8 corner points.
Because the condition of welding lines, arc turning plates and the like exist at the intersection of three faces of the cargo hold and the volume of the target ball is large, the three-dimensional coordinates of the corner points cannot be directly detected, and the three-dimensional coordinates of the corner points are indirectly detected by detecting the adjacent three faces and then intersecting.
The frog leaping of the laser tracker is an operation of ensuring that data measured before and after displacement of the laser tracker are unified in a coordinate system through some operations and settings. In the cargo hold of the LNG ship, all angular point coordinates cannot be detected at one position due to the blocking of the installation platform structure, so that frog-leaping operation is required.
And selecting a device position target for defining measurement in polyworks software, sequentially placing target balls on the target ball bases placed on the F, J surface in the step 2, and detecting the coordinates of the target ball bases one by one to serve as a reference point of a unified coordinate system before and after the displacement of the laser tracker.
After all the corner points in the surface D are measured, mobile equipment is selected in polyworks software, the laser tracker is moved into the square frame of the surface B, and the coordinates of all the target ball bases are detected again by using the target balls. The objects with larger deviations are deselected in polyworks software, and more than 3 objects are reserved as much as possible, as shown in fig. 7.
And S4, detecting the corner points of the B surface, and detecting and outputting three-dimensional coordinates of 8 corner points of the B surface according to the method of the step S3.
Calculating side lengths and diagonals
In three-dimensional space, the distance between two target balls =. To reduce the calculation effort, the above formula is input into the excel table, and 16 corner coordinates are input, so that the corresponding side length or diagonal dimension can be generated at another position, as shown in fig. 8.
As shown in fig. 8, B3, C3, D3 are X, Y, Z coordinates of the corner point ABE in the Excel table, and B13, C13, D13 are X, Y, Z coordinates of the corner point HBA in the Excel table, and the distance (i.e., the side length BA) between them is expressed as "= ((B3-B13)/(2+ (C3-C13)/(2+ (D3-D13)/(2))0.5).
The three-dimensional coordinates of the corner point ABE are (-24722.5, -10411.9,17242.5) and (-24722.5,10411.9,17242.5), respectively, and the distance between the two points HBA is ==20823.8。
Inputting calculation formulas of 24 side lengths and 40 diagonals of the cargo hold into an excel worksheet according to the method of the step S4, and calculating all the side lengths and the diagonal sizes.
S5, comparing the calculated side length and diagonal line size with the theoretical size, checking whether the calculated side length and diagonal line size are out of tolerance, retesting the data by a disc ruler or a range finder direct measurement method if the calculated side length and diagonal line size are out of tolerance, comparing the calculated side length and diagonal line size with the theoretical size, and acquiring the measured data of the laser tracker if the calculated side length and diagonal line size are out of tolerance.
Claims (7)
1. A cargo hold size measuring method of MARKIII cargo containment system is characterized in that the cargo hold has 10 sides, namely a bow side, a stern side, a port side, a starboard side, a top side, a bottom side, a left upper side, a right upper side, a left lower side and a right lower side, wherein three adjacent sides form an angular point, and the total is 16 angular points;
s1, fixing a laser tracker at the center of a bow surface or a stern surface of a cargo compartment, arranging a plurality of target balls in three surfaces corresponding to each corner point, wherein the target balls are close to adjacent corner points, and the plurality of target balls are distributed and staggered up and down;
s2, using laser pens to irradiate target balls in a left side surface and a right side surface at the positions of a laser tracker of a bow surface and a stern surface simultaneously, observing whether laser can detect all the target balls in the left side surface and the right side surface simultaneously, and if the target balls cannot be detected somewhere, shifting the target balls to ensure that the target balls in the left side surface and the right side surface can be irradiated by the laser pens in two positions simultaneously;
S3, inputting the actual diameter of the target ball into polyworks operation software, detecting targets in three planes corresponding to the current corner point for the first time by using a laser tracker, lifting the target ball after the first detection is finished, detecting for the second time, and creating planes in polyworks software after the second detection is finished, wherein the coordinates of the intersection point formed by intersecting the three planes corresponding to the current corner point are the three-dimensional coordinates of the current corner point;
sequentially measuring to obtain three-dimensional coordinates of 16 corner points by adopting the method of the step S3;
s4, calculating side length and diagonal line
Inputting three-dimensional coordinates of 16 corner points into an excel table, and calculating the distance between two points according to the formula =Obtaining the side length or diagonal line size corresponding to each corner point;
Wherein X1 and X2 are X coordinates of two corner points;
Y1 and Y2 are Y coordinates of two corner points;
z1 and Z2 are Z coordinates of two corner points;
Finally outputting 24 side lengths and 40 diagonal sizes of the cargo hold in an excel table;
and S5, checking the result, comparing the calculated side length and diagonal line size with the theoretical size, checking whether the calculated side length and diagonal line size are out of tolerance, retesting the data by a method of directly measuring by a disc ruler or a range finder if some data are out of tolerance, comparing the deviation of the calculated side length and diagonal line size with the measured data of the laser tracker, and acquiring the measured data of the laser tracker if the deviation is within a specified range.
2. The method of claim 1 wherein a frame is attached to the center of the bow or stern of the cargo compartment using masking tape and the laser tracker base is secured to the bulkhead within the frame by the base.
3. The method of claim 1 wherein the target ball mount is secured to the bulkhead by hot melt adhesive.
4. The method for measuring the size of the cargo hold of the MARKIII cargo containment system according to claim 1, wherein the distance between the target sphere and the adjacent corner point is 100 mm-300 mm.
5. The method of claim 1 wherein the laser tracker is mounted to the bulkhead by a base, the base thickness + the laser tracker height < the mounting platform per layer boundary to bulkhead distance.
6. The method for measuring the size of a cargo hold of a MARKIII cargo containment system according to claim 1, wherein in step S3, the 8 corner points on one of the bow surface and the stern surface are measured, and after the measurement, the 8 corner points on the other surface are measured.
7. The method for measuring the size of the cargo hold of the MARKIII cargo containment system according to claim 1, wherein after measuring 8 corner points on one surface, frog-leaping operation is performed on polyworks software, and then 8 corner points on the other surface are measured, so as to ensure that the data measured before and after the displacement of the laser tracker are unified in a coordinate system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202511887238.5A CN121876830A (en) | 2025-12-15 | 2025-12-15 | A method for measuring cargo hold dimensions of the MARK III cargo containment system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202511887238.5A CN121876830A (en) | 2025-12-15 | 2025-12-15 | A method for measuring cargo hold dimensions of the MARK III cargo containment system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN121876830A true CN121876830A (en) | 2026-04-17 |
Family
ID=99417226
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202511887238.5A Pending CN121876830A (en) | 2025-12-15 | 2025-12-15 | A method for measuring cargo hold dimensions of the MARK III cargo containment system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN121876830A (en) |
-
2025
- 2025-12-15 CN CN202511887238.5A patent/CN121876830A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112415493B (en) | Coordinate error correction method for three-dimensional scanning laser radar | |
| CN103454619B (en) | Electrical axis optical calibration system of spaceborne microwave tracking-pointing radar and calibration method thereof | |
| KR101408349B1 (en) | Ship resetting method and coordinate measuring system for resetting ship | |
| EP1390688B1 (en) | Apparatus and method for automatically determining the position of a measuring arm on the basis of an array of reference points | |
| CN102506702B (en) | Large three-dimensional coordinate measuring method with laser tracking and device | |
| EP0329635A2 (en) | Method for determining positional errors and for compensating for such errors, and apparatus for carrying out the method | |
| CN110487210B (en) | Measurement method of honeycomb core surface profile | |
| CN107478162A (en) | A kind of stand mounting coordinate system construction method | |
| CN113587819A (en) | Three-laser-tracking-based large-scale space pose dynamic measurement method and measurement precision verification method | |
| CN103737433B (en) | Large-size components combined type accuracy measurement method | |
| CN110274666B (en) | ADCP (advanced digital content control protocol) metrological verification method for river flow application | |
| CN102519430A (en) | Horizontal laser measurement system and method for airplane | |
| CN103353279B (en) | A kind of LNG ship cargo tank insulated case and the pinpoint method of flange bolt | |
| CN107588929B (en) | Calibration method and calibrator for spherical screen projection/tracking system | |
| CN110779503A (en) | Three-dimensional precision control network measuring method | |
| CN115682982B (en) | System and method for calibrating three-dimensional measurement results based on variable large-size polyhedron | |
| CN121876830A (en) | A method for measuring cargo hold dimensions of the MARK III cargo containment system | |
| CN119379923B (en) | A method for marking the baseline of a film-type cargo containment system based on drones | |
| CN115950388A (en) | Device and method for measuring translation errors of two shafts and reflecting mirror of reflective laser tracker | |
| CN120274798A (en) | Laser installation deviation calibration method for inclination measurement system | |
| CN111412888B (en) | Building size measuring method | |
| CN204831167U (en) | Measurement device for whole curved surface of thing is leveled in accurate measurement | |
| CN108469241A (en) | A kind of the determination method, apparatus and storage medium of bay section assembly precision | |
| CN202361986U (en) | Horizontal laser measuring system for airplanes | |
| CN115493617B (en) | A laser tracking attitude angle on-site accuracy assessment system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination |