CN112378477B - Large aspect ratio horizontal tank volume continuous laser scanning internal measuring device and measuring method - Google Patents

Abstract

The invention discloses a large length-diameter ratio horizontal tank volume continuous laser scanning internal measurement device and a measurement method, belonging to the technical field of laser scanning, wherein the technical scheme comprises a laser scanner and a guide rail arranged along the axial direction of a horizontal tank, and a transmission assembly for driving the laser scanner to slide along the length direction of the guide rail is arranged on the guide rail; splicing targets are respectively arranged in the horizontal tank and at the inlet end and the bottom end which are close to the horizontal tank; and a data processor is arranged outside the horizontal tank and connected with the laser scanner. This scheme adopts laser scanner along circular cross section two-dimensional scanning and adds the mode that removes along guide rail horizontal equidistance when measuring jar body face of cylinder part point cloud data, when jar body both ends point data measurement, through rationally establishing the station, rationally sets up the position of data concatenation target in effective scanning range, guarantees that the some data of end top portion measured data and the point cloud data after the concatenation have same measurement accuracy, realizes big length-diameter ratio horizontal jar of volumetric quick high accuracy measurement.

Description

Large length-to-diameter ratio horizontal tank volume continuous laser scanning internal measurement device and measurement method

technical field

The invention belongs to the technical field of laser scanning, and in particular relates to a volume continuous laser scanning internal measuring device and a measuring method of a horizontal tank with a large length-to-diameter ratio.

Background technique

The measurement of the volume of large tanks is of great significance. International bulk liquid trade is often carried out with tank containers. Whether the volume of tanks can be accurately measured is not only directly related to the interests of our country, but also related to our image and reputation; The volume measurement accuracy of rocket and other spacecraft fuel tanks is directly related to the quality of the flight results. Insufficient fuel affects the flight mission, and too much fuel increases the payload of the spacecraft and affects the carrying capacity. At present, traditional geometric measurement methods are mainly used for the measurement of tank volume, including girth method, optical reference line method, optical measurement method with guide rail, etc., but these measurement methods are generally time-consuming and labor-intensive, and the measurement accuracy is not high. For large tanks with complex internal structures (tanks with ribs, ribs, anti-sway plates and other accessories inside), such as spacecraft fuel tanks such as rockets, the flow method is generally used for measurement at present, and the measurement accuracy is high. The measurement cycle of the box is usually 3 days to 5 days, and the measurement efficiency is low.

Japan's Sokkia TCCS Oil Tank Volume Calibration System is an internal test method for vertical cylindrical tanks (Sokkia TCCS Oil Tank Volume Calibration System, Sokkia High-end Total Station System Integration White Paper (2)), its principle is: The instrument is installed near the center of the circle in the vertical oil tank, and the total station scans the three-dimensional coordinates on the section of each ring plate with a certain step (step angle or step distance), and then fits the radius of each ring plate, and then The volume of the oil tank is obtained by further processing by computer software. The characteristics of this technical solution are: (1) This method calculates the volume of each ring plate by scanning the horizontal section and fitting the radius of each ring plate to obtain the overall volume. For horizontal tanks, the horizontal section is no longer Therefore, it is not possible to measure the volume of horizontal tanks; (2) This method uses a total station for sampling, and the sampling points are sparse. It can only measure the volume of metal tanks with smooth inner walls, and cannot measure metal tanks with complex interiors. The details of the features affect the measurement accuracy.

Patent No. CN201210524701.6 discloses a volume measurement method and device based on three-dimensional laser scanning. This technical solution proposes an internal measurement method in which the three-dimensional laser scanner is placed upright or upside down at the manhole of the tank through the instrument suspension, and the data measured by the laser scanner is modeled with a spatial grid to obtain all reconstructed data. Multiple slice shapes of the tank are used to calculate the volume of the tank. The characteristics of this technical solution are: (1) This method is mainly aimed at measuring tanks with a small length-to-diameter ratio. For tanks with a large length-to-diameter ratio, the measurement accuracy is low at a distance from the scanner, resulting in unequal measurement accuracy. Finally, Participate in the volume calculation with the same weight, which affects the measurement accuracy of the tank volume; (2) For tanks with a large aspect ratio and complex internal structure, the laser scanner cannot extend into the tank along the axis of the tank to measure the detailed features; (3) For tanks with a large length-to-diameter ratio and a complex internal structure, this method is more likely to produce outliers with large errors and cause measurement errors.

The China Jiliang Institute proposed an internal measurement method for the volume of vertical metal tanks based on 3D laser scanning (Zhou Xiaoxue. Application research of 3D laser scanning technology in volume measurement of vertical metal tanks. China Jiliang Institute, 2014.). This method is a vertical tank volume measurement method, which is suitable for volume measurement with a small length-to-diameter ratio (generally about 1) and smooth inner walls without detailed structures. The solution is to set up the laser scanner on the bottom of the vertical tank. The three measuring stations are distributed in a triangle, and three targets distributed in a triangle are set on the bottom of the tank for data splicing. In terms of data processing, the point cloud data is used to The radius of the ring plate divides the metal tank into countless small cylinders in the axial direction, and then calculates the volume of the metal tank by superposition. The characteristics of this technical solution are: (1) The method of completing data splicing through three-station measurement and setting targets at the bottom of the tank can effectively avoid the problem of light blocking by accessories in the tank to a certain extent, but for tanks with relatively large lengths , can not solve the influence of the light-blocking structure far away from the scanner and the detailed structure of the ribs and ribs on the inner surface of the tank, so it cannot be measured; There is an error in the target positioning caused by the tilt of the laser light; (3) The measurement accuracy of the tank part far away from the scanner is low, and finally the volume is calculated with the same accuracy, which affects the volume measurement accuracy; (4) The measurement plan, measurement The structure and data processing method determine that this method cannot be used for the measurement of horizontal tanks.

In summary, the current 3D laser scanning method is often used to measure the volume of tanks with a relatively small length-to-diameter ratio. For tanks with a large length-to-diameter ratio, the point cloud data measurement accuracy is not equal, and the point cloud data with different measurement accuracy is calculated according to the same accuracy. Participate in volume calculation; and for horizontal tanks with large length and diameter, they cannot extend into the tank along the axis to measure the detailed features, and it is easier to produce outliers and cause measurement errors; while the geometry currently used for tank volume measurement The measurement method and the total station method have low measurement accuracy and low measurement efficiency. Although the flow method can obtain high measurement accuracy, the measurement efficiency is low. Therefore, it is urgent to propose a high-precision, high-efficiency large-length-to-diameter ratio complex structure horizontal tank volume continuous laser scanning internal measurement device and measurement method to meet my country's rapid and high demand for oil tank metering and spacecraft fuel storage tank volume. Accuracy measurement and other aspects of the demand.

Contents of the invention

The purpose of the present invention is to solve the problem that the volume measurement of horizontal tanks with large length-to-diameter ratio and complex structure cannot be realized quickly and with high accuracy in the existing technical solutions, and propose a continuous laser scanning internal measurement device for volume of horizontal tanks with large length-to-diameter ratio and The measurement method realizes rapid and high-precision measurement of the volume of a large aspect ratio horizontal tank body, especially a large aspect ratio horizontal tank body with a complex internal structure.

In order to realize the foregoing invention object, a technical scheme provided by the present invention is as follows:

A continuous laser scanning internal measurement device for a horizontal tank volume with a large aspect ratio, comprising a laser scanner and a guide rail arranged along the axis of the horizontal tank. direction sliding transmission assembly; splicing targets are respectively provided in the horizontal tank and at the inlet end and the bottom end close to the horizontal tank; a data processor is provided outside the horizontal tank, and the data processor is connected to The laser scanner; the data processor receives the point cloud data of the laser scanner, and filters and stitches the received point cloud data, and calculates the volume value based on the spliced point cloud data; stitches the target installation position Located on the middle section and within the effective scanning range when the laser scanner scans at both ends of the middle section, the effective scanning range is determined by the horizontal tank cylindrical generatrix and the laser scanner The minimum grazing angle α of the laser light is determined, and the angle between the laser ray and the generatrix is greater than/equal to the minimum grazing angle α; the minimum grazing angle α=arctan(d/e), where, d is the laser beam diameter of the laser scanner, and e is the measurement deviation value, and its unit is mm.

Preferably, the transmission assembly includes a precision transmission screw that is rotatably arranged on the guide rail, and a precision servo motor that is fixed at one end of the guide rail in the length direction and drives the rotation of the precision transmission screw. A slide block, the slide block is screwed on the precision transmission screw; the laser scanner is arranged on the slide block.

Preferably, a controller connected to the precision servo motor is provided on the outside of the horizontal tank, and the controller controls the precision servo motor to drive the laser scanner to move equidistantly and intermittently.

Preferably, two groups of splicing targets are arranged at intervals along the length of the slide rail, the splicing targets include a plurality of targets, and the plurality of targets are located on different straight lines.

In order to realize the above-mentioned object of the invention, another technical scheme provided by the present invention is as follows:

A continuous laser scanning measurement method for the volume of a horizontal tank with a large aspect ratio, using the above-mentioned continuous laser scanning internal measurement device for the volume of a horizontal tank with a large aspect ratio, comprising the following steps:

Step 1. Install one end of the guide rail inside the horizontal tank along the axial direction, and install the splicing target in the horizontal tank, including the first splicing target near the inlet end and the second splicing target near the bottom end;

Step 2. Control the precision servo motor to work, drive the laser scanner to move into the horizontal tank, and when it is located at the interface between the entrance end and the middle section, the laser scanner scans the point cloud data at the entrance end, and the The middle section contains point cloud data of the tank section where the first splicing target is located;

Step 3. Control the laser scanner to move equidistantly and intermittently along the guide rail. After each movement stops, control the laser scanner to scan for a week along the vertical axis of the horizontal tank to obtain the 3D point cloud data of the middle section;

Step 4, when the laser scanner moves along the guide rail to the interface between the bottom end and the middle section, acquire the point cloud data of the bottom end and the point cloud data of the tank section where the second splicing target is located in the middle section ;

Step 5, splicing the point cloud data of the inlet end, the bottom end and the middle section;

Step 6, calculating the volume based on the obtained point cloud data of the horizontal tank;

The steps of obtaining the 3D point cloud data of the middle segment include:

Each time the laser scanner stops moving, it acquires two-dimensional point cloud data in the circumferential direction of the horizontal tank, and based on the distance value of each movement of the laser scanner and the two-dimensional point cloud data, splicing to form the 3D point cloud data.

Preferably, the step of splicing the point cloud data of the entry port, the bottom end and the middle section includes splicing the point cloud data of the entry port and the middle section based on the point cloud data of the entry port and the point cloud data of the first splicing target , forming local point cloud data; splicing the bottom point cloud data and the local point cloud data based on the bottom point cloud data and the point cloud data of the second stitching target to form the overall point cloud data of the horizontal tank.

Preferably, the installation positions of the splicing targets are respectively located on the middle section of the laser scanner and within the effective scanning range of the laser scanner when scanning at both ends of the middle section.

Preferably, the step of determining the effective scanning range includes: calculating the minimum grazing angle α, and the minimum grazing angle α is the distance between the generatrix of the cylindrical surface of the horizontal tank and the laser beam of the laser scanner Included angle: within the effective scanning range, the included angle between the laser beam of the laser scanner and the generatrix of the cylindrical surface of the horizontal tank is greater than or equal to the minimum grazing angle α.

Preferably, the step of calculating the minimum grazing angle α includes obtaining the laser beam diameter d of the laser scanner, preset measurement deviation e, and the minimum grazing angle α=arctan(d/e), wherein, The units of diameter d and measurement deviation e are millimeters.

The volume continuous laser scanning internal measurement device and measurement method of a large aspect ratio horizontal tank provided by the present invention have the following advantages:

1. The present invention can be applied to the volume measurement of a horizontal tank with a large length-to-diameter ratio and a complex internal structure. Existing laser scanning measurement methods cannot measure tanks with large aspect ratios; this measuring device can measure the volume of horizontal tanks with large aspect ratios, and the laser scanner is installed on the horizontal tank through guide rails and transmission components. Near the axis, when measuring, the laser scanner moves along the guide rail, scans and measures the inside of the horizontal tank during intermittent movement, and obtains the 3D point cloud data of the middle section, and at the same time, obtains the points at both ends by setting up reasonable stations Cloud data, obtain high-precision tank measurement data through data splicing. It solves the problem that the current existing technology cannot measure the volume of a horizontal tank with a large length ratio and diameter.

2. The present invention can realize high-precision measurement of point cloud data of the tank body through reasonable station measurement, and the accuracy of the point cloud data is the same, which can effectively improve the calculation accuracy of the tank body volume. When measuring the point cloud data of the cylindrical surface of the tank, the laser scanner is used to scan along the circular section two-dimensionally and move horizontally along the guide rail, which ensures that the point cloud data measured on the cylindrical surface of the tank has the characteristics of high precision and equal precision. When measuring the data of the top part of the body, the position of the data splicing target is reasonably set by controlling the minimum grazing angle, so as to ensure that the measurement data of the top part and the spliced point cloud data have the same measurement accuracy.

3. The technical solution proposed by the present invention can measure the volume of large horizontal tanks with complex internal structures with high efficiency and high precision. Existing measurement methods do not measure tanks with detailed structures such as ribs, ribs, and anti-shake plates on the inner surface; the present invention obtains massive point cloud data through rapid scanning with a laser scanner, and can build an accurate three-dimensional model of the tank. Compared with the traditional measurement method, the measurement accuracy and measurement efficiency are higher; for large horizontal tanks with complex internal structures, the laser scanning method often requires several stations for measurement, and manual operation is required for each station change process, and the measurement efficiency is low. The present invention It can break through this limitation and obtain all measurement data through motor drive. Compared with the traditional single measurement station group measurement, it avoids manual operation, station change, multiple frequency modulation and other processes, and the measurement efficiency is increased by more than 60%. The measurement accuracy is improved by more than 20%.

Description of drawings

Fig. 1 is a schematic diagram of a large aspect ratio horizontal tank volume continuous laser scanning internal measurement device of the present invention;

Fig. 2 is a schematic diagram of a large length-to-diameter ratio horizontal tank volume continuous laser scanning internal measurement device of the present invention protruding from each tank section;

Fig. 3 is a partial schematic diagram of a protruding transmission assembly of a large aspect ratio horizontal tank volume continuous laser scanning internal measurement device of the present invention;

Fig. 4 is the schematic diagram of the grazing angle when the laser beam of the present invention is perpendicular to the horizontal tank inner wall;

Fig. 5 is a schematic diagram of the minimum grazing angle when the laser beam of the present invention is inclined to the inner wall of a horizontal tank.

Reference signs in the figure:

100. Laser scanner; 110. Laser beam; 200. Guide rail; 300. Transmission component; 310. Precision transmission screw; 320. Precision servo motor; 330. Slider; 400. Splicing target; 410. First splicing target; 420, the second stitching target; 500, the controller; 600, the data processor; 700, the horizontal tank; 710, the middle section; 720, the inlet end; 730, the bottom end;

A, end face A; B, cross-section B; C, cross-section C; D, cross-section D; E, cross-section E; F, end face F; d, diameter of laser light; e, measurement deviation; α, minimum grazing angle.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Example 1

The present invention provides a large length-to-diameter ratio horizontal tank volume continuous laser scanning internal measurement device, see Fig. 1-Fig. and can slide along the length direction of the guide rail 200 , the laser scanner 100 is arranged on the transmission assembly 300 . When in use, the transmission assembly 300 drives the laser scanner 100 to move along the length direction of the guide rail 200. During the movement, the horizontal tank 700 is scanned to obtain point cloud data, and the horizontal tank 700 is calculated based on the point cloud data. The volume of the splicing target 400 is located on the middle section 710, and is located in the effective scanning range of the laser scanner 100 when scanning at both ends of the middle section 710. The effective scanning range is formed by the horizontal tank 700 cylindrical generatrix and the laser scanner The minimum grazing angle α of the laser beam of 100 is determined, and the angle between the laser ray and the generatrix is greater than/equal to the minimum grazing angle α; the minimum grazing angle α=arctan(d/e), where d is the laser scanner The diameter of laser light 110 of 100, e is the measurement deviation value, and its unit is millimeter.

Wherein, the guide rail 200 is arranged parallel to the axial direction of the horizontal tank 700. Specifically, the guide rail 200 can be erected near the axis of the tank body during use, and then the transmission assembly 300 can drive the laser scanner 100 along the axis direction of the tank body. Move, and then carry out relatively accurate scanning to the inside of horizontal tank 700.

Wherein, the guide rail 200 adopts a precision linear guide rail 200 .

The transmission assembly 300 includes a precision transmission screw 310 , a precision servo motor 320 and a slider 330 . Among them, the precision transmission screw 310 is arranged on the guide rail 200, and the precision transmission screw 310 is parallel to the length direction of the guide rail 200. One end of the precision transmission screw 310 is connected to the guide rail 200 in rotation, and the other end is connected to the output of the precision servo motor 320. The shaft is connected, and the precision drive screw 310 can rotate relative to the guide rail 200 when in use. The precision servo motor 320 is mounted on one end of the guide rail 200 . Specifically, the precision servo motor 320 is located at the outer end of the horizontal tank 700 when in use, and the precision servo motor 320 drives the precision transmission screw 310 to rotate when in use.

The slider 330 is slidably arranged on the guide rail 200, and the slider 330 is screwed with the precision transmission screw 310. Specifically, a through screw hole is opened on the slider 330, and the precision transmission screw 310 passes through the screw hole. When the transmission lead screw 310 rotates, it drives the slider 330 to slide along the length direction of the guide rail 200 . One side of the slider 330 is a working surface, and this side faces the outside, and faces the side of the inner wall of the horizontal tank 700 during use, on which the laser scanner 100 is installed.

Wherein, the scanning range of the laser scanner 100 along the horizontal direction is 0-180 degrees, and the scanning range of the vertical direction is 0-360 degrees. The horizontal direction and vertical direction in the above description are based on the horizontal tank 700: the horizontal direction refers to the direction parallel to the axis of the horizontal tank 700, that is, the direction parallel to the length of the guide rail 200; the vertical direction refers to the direction perpendicular to the axis of the horizontal tank 700; The axis of the horizontal tank 700 is the direction perpendicular to the length of the guide rail 200 .

Wherein, the middle section 710 of the horizontal tank 700 is a cylindrical tank section with a circular cross section, and the inlet end 720 and the bottom end 730 are arc surfaces respectively. Splicing targets 400 are provided at both ends of the middle section 710 and near the inlet end 720 and the bottom end 730 respectively. Specifically, the mosaic target 400 includes a first mosaic target 410 near the inlet end 720 and a second mosaic target 420 near the bottom end 730 .

When working, the laser scanner 100 moves on the guide rail 200, and when it moves to both ends of the middle section 710, it scans the point cloud data of the entrance end 720 and the point cloud data of a section of the middle section 710 including the first splicing target 410, That is, scan the point cloud data of the EF segment and the DE segment and the point cloud data of the bottom 730, and the point cloud data of the middle segment 710 including the second splicing target 420, specifically scan the point cloud data of the AB segment and the BC segment . Afterwards, the point cloud data of the inlet end 720 and the bottom end 730 are spliced with the point cloud data of the middle section 710 by splicing the target 400 to form the overall point cloud data of the horizontal tank 700.

The explanation is as follows: the top of the inlet end 720 of the horizontal tank 700 is set as end face F, the bottom of the bottom end 730 is set as end face A, the end of the middle section 710 near the inlet end 720 is section E, and the end near the bottom end 730 is section B. During scanning, when the laser scanner 100 is located on the section E, the effective scanning range of the laser scanner 100 at this time is the tank segment between the section D and the end surface F, and the splicing target 410 is located between the section D and the section E. When the laser scanner 100 is located on the section B, the effective scanning range of the laser scanner 100 at this time is the tank segment between the section A and the end surface C, and the stitching target 420 is located between the section B and the section C.

The effective scanning range mentioned above is determined based on the minimum grazing angle α. Wherein, the minimum grazing angle α is the angle formed by the generatrix of the cylindrical surface of the horizontal tank 700 and the laser light 110 of the laser scanner 100 . Within the effective scanning range, the included angle between the laser beam 110 of the laser scanner 100 and the generatrix of the cylindrical surface of the horizontal tank 700 is greater than or equal to the minimum grazing angle α.

When the minimum grazing angle is smaller, the error is relatively larger. The position of the stitching target 400 is determined by calculating the minimum grazing angle.

The inlet end 720 and the bottom end 730 of the horizontal tank 700 have arc-shaped arc surfaces respectively. When calculating the inner volume of the arc surface, the laser scanner 100 is arranged at the two ends of the middle section 710. The middle section 710 refers to the horizontal arc surface. Tank 700 is a cylindrical tank section.

The splicing target 400 is located within the range where the angle between the laser beam 110 of the laser scanner 100 and the generatrix of the cylindrical surface of the tank is greater than or equal to the minimum grazing angle.

There are two groups of mosaic targets 400 arranged at intervals along the length direction of the guide rail 200 , the mosaic targets 400 include multiple targets, and the multiple targets are located on different straight lines.

A controller 500 is provided at one end of the guide rail 200 and outside the horizontal tank 700 . The controller 500 controls the precision servo motor 320 to drive the laser scanner 100 to move equidistantly and intermittently. Specifically, the laser scanner 100 stops for a period of time after moving the same distance each time. After stopping, the laser scanner 100 scans. When the laser scanner 100 is located in the middle section 710 of the horizontal tank 700, the laser scanner 100 The scanner 100 scans along the horizontal direction, and the scanning range is 0-360 degrees. The 3D point cloud data of the middle segment 710 can be reasonably calculated by scanning the obtained 2D point cloud data and the moving distance value of the laser scanner 100 .

One end of the guide rail 200 and the outside of the horizontal tank 700 are provided with a data processor 600, the data processor 600 receives the point cloud data scanned by the laser scanner 100, and combines the point cloud data of the entrance end 720 and the bottom end 730 with the middle section The point cloud data of 710 is spliced, and then the point cloud data of the complete horizontal tank 700 is obtained, and the volume data of the tank body is obtained through the subsequent volume calculation algorithm.

It should be noted that the above data processor 600 and controller 500 may be integrated in a computer or other electronic devices.

Example 2

A continuous laser scanning measurement method for the volume of a horizontal tank with a large aspect ratio, using the above-mentioned continuous laser scanning internal measurement device for the volume of a horizontal tank with a large aspect ratio, as shown in Figures 2-5, comprising the following steps:

Step 1. Install the internal test device inside the horizontal tank 700 and install the splicing target 400 in the horizontal tank 700 . The splicing target 400 is located near the inlet end 720 and the bottom end 730 of the horizontal tank 700 .

Step 2, control the precision servo motor 320 to work, drive the laser scanner 100 to move to the interface between the middle section 710 and the entrance end 720, the laser scanner 100 scans the point cloud data of the entrance end 720, and the middle section 710 contains the first splicing The point cloud data of the tank section where the target 410 is located.

Step 3. Control the laser scanner 100 to move equidistantly and intermittently along the guide rail 200. After each movement stops, control the laser scanner 100 to scan a circle along the axis vertical to the horizontal tank 700 to obtain the 3D point cloud data of the middle section 710.

Step 4: When the laser scanner 100 moves along the guide rail 200 to the interface between the bottom end 730 and the middle section 710, measure the point cloud data of the bottom end 730 and the point cloud data of the tank section where the second stitching target 420 is located in the middle section 710 .

Step 5, splicing the point cloud data of the inlet end 720 , the bottom end 730 and the middle section 710 of the horizontal tank 700 .

Step 6, calculating the volume based on the obtained point cloud data of the horizontal tank 700;

The step of obtaining the three-dimensional point cloud data of the middle segment 710 includes:

Each time the laser scanner 100 stops moving, it acquires two-dimensional point cloud data in the circumferential direction of the horizontal tank 700, and based on the distance value and the two-dimensional point cloud data of each movement of the laser scanner 100, splicing forms three-dimensional point cloud data.

It should be noted that the point cloud data of the first stitched target 410 and the point cloud data of the second stitched target 420 mentioned above specifically refer to identifying the stitched targets and obtaining the center coordinate values of each target in each stitched target. The point cloud data of each tank segment is stitched according to the center coordinates of each target in the stitching target.

Specifically, in step 1, the splicing target 400 includes a first splicing target 410 located at both ends of the middle section 710 and close to the inlet end 720 and a second splicing target 420 close to the bottom end 730 .

The splicing target 400 is installed on the middle section 710 , and is located within the effective scanning range of the laser scanner 100 when scanning the two ends of the middle section 710 .

Among them, the steps of determining the effective scanning range include:

Calculate the minimum grazing angle α, which is the angle formed by the generatrix of the cylindrical surface of the horizontal tank 700 and the laser light 110 of the laser scanner 100 . Within the effective scanning range, the included angle between the laser beam 110 of the laser scanner 100 and the generatrix of the cylindrical surface of the horizontal tank 700 is greater than or equal to the minimum grazing angle α.

When the minimum grazing angle is smaller, the error is relatively larger. The position of the stitching target 400 is determined by calculating the minimum grazing angle.

The step of calculating the minimum grazing angle includes obtaining the diameter d of the laser beam 110 of the laser scanner 100 , preset measurement deviation e, and the minimum grazing angle α=arctan(d/e). Wherein, the measurement deviation value refers to the measurement deviation caused by the oblique irradiation of the laser; the units of the diameter d and the measurement deviation value e are millimeters. For example, laser diameter=1mm, measurement deviation value e=1mm, then minimum grazing angle α=arctan(d/e)=45°. When the minimum grazing angle is 45°, the lying position of the splicing target 400 is within the range where the grazing angle is greater than 45°, wherein the grazing angle is the generatrix of the cylindrical surface of the horizontal tank 700 and the laser beam 110 of the laser scanner 100 angle.

The specific explanation is as follows: the top of the inlet end 720 of the horizontal tank 700 is set as end face F, the bottom of the bottom end 730 is set as end face A, the end of the middle section 710 near the inlet end 720 is section E, and the end near the bottom end 730 is section B. During scanning, when the laser scanner 100 is located on the section E, the range determined by the minimum grazing angle α is the section D and the end surface F, and the effective scanning range of the laser scanner 100 at this time is between the section D and the end surface F The tank section of , the stitching target 410 is located between section D and section E. When the laser scanner 100 is located on section B, the range determined by the minimum grazing angle α is section A and end surface C, and the effective scanning range of laser scanner 100 at this time is the tank section between section A and end surface C. Splicing target 420 is located between section B and section C.

In step 3, the step of controlling the laser scanner 100 to move equidistantly and intermittently along the guide rail 200 includes controlling the laser scanner 100 to stop after moving a certain distance each time. After each movement stops, the laser scanner 100 is controlled to scan a circle along the axis vertical to the horizontal tank 700 to acquire the three-dimensional point cloud data of the middle section 710 .

The step of acquiring the three-dimensional point cloud data of the middle section 710 includes: acquiring the two-dimensional point cloud data of the circumferential direction of the horizontal tank 700 every time the laser scanner 100 stops moving, based on the distance value of each movement of the laser scanner 100 and The two-dimensional point cloud data is spliced to form the three-dimensional point cloud data of the middle segment. Since the moving distance along the direction of the guide rail 200 is the same each time, and the two-dimensional point cloud data of the horizontal tank 700 obtained by scanning, the three-dimensional point cloud data of the middle section 710 can be calculated.

In step 5, the step of splicing the point cloud data of the entry port 720, the bottom end 730 and the middle section 710 includes splicing the entry port 720 and the middle section based on the point cloud data of the entry port 720 and the point cloud data of the first splicing target 410. The point cloud data of segment 710 forms local point cloud data. Since the position of the first stitching target 410 is relatively fixed, the point cloud data of the entry end 720 and the point cloud data of the middle segment 710 can be stitched according to the first stitching target 410 .

Based on the point cloud data of the bottom end 730 and the point cloud data of the second stitching target 420, the point cloud data and local point cloud data of the bottom end 730 are spliced to form the overall point cloud data of the horizontal tank.

Through the splicing process of the above point cloud data, the point cloud data of the middle section, the bottom end and the inlet end are spliced to form the overall point cloud data of the horizontal tank.

By adopting the above-mentioned embodiment, the volume of the horizontal tank 700 with a large aspect ratio can be measured, and the laser scanner 100 is erected on the axis position of the horizontal tank 700 through the guide rail 200 and the transmission assembly 300. During measurement, the laser scanner 100 Moving along the guide rail 200, the interior of the horizontal tank 700 is scanned and measured during intermittent movement, and at the same time, high-precision measurement data is obtained at both ends by splicing multi-station measurement data. It solves the problem that the current existing technology cannot measure the volume of a horizontal tank with a large length ratio and diameter.

The present invention can realize the high-precision measurement of the point cloud data of the tank through reasonable station measurement, and the accuracy of the point cloud data is the same, and can effectively improve the calculation accuracy of the tank volume. When measuring the point cloud data of the cylindrical surface of the tank, the laser scanner is used to scan two-dimensionally along the circular section and move horizontally along the guide rail 200, which ensures that the point cloud data measured on the cylindrical surface of the tank has the characteristics of high precision and equal precision. When measuring the data of the top part of the tank body, the position of the data splicing target 400 is reasonably set by controlling the minimum grazing angle, so as to ensure that the measurement data of the top part and the spliced point cloud data have the same measurement accuracy.

Existing measurement methods cannot measure tanks with detailed structures such as ribs, ribs, and anti-shake plates on the inner surface; the present invention obtains massive point cloud data through rapid scanning with a laser scanner, and can build an accurate three-dimensional model of the tank. Compared with the traditional measurement method, the measurement accuracy and measurement efficiency are higher; for large horizontal tanks with complex internal structures, the laser scanning method often requires several stations for measurement, and manual operation is required for each station change process, and the measurement efficiency is low. The present invention This limitation can be broken, and all measurement data can be obtained through motor drive, which effectively improves measurement accuracy and measurement efficiency.

The above-mentioned embodiments only express the implementation manner of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (9)

1. A large length-to-diameter ratio horizontal tank volume continuous laser scanning internal measurement device, characterized in that: it includes a laser scanner (100), a guide rail (200) arranged along the axial direction of the horizontal tank (700), in the The guide rail (200) is provided with a transmission assembly (300) that drives the laser scanner (100) to slide along the length direction of the guide rail (200); Splicing targets (400) are respectively provided at the inlet end (720) and the bottom end (730) of the horizontal tank (700) and close to the horizontal tank (700); The outside of the horizontal tank (700) is provided with a data processor (600), the data processor (600) is connected to the laser scanner (100), and the data processor (600) receives the laser scanner (100) of the point cloud data, and filtering and splicing the received point cloud data, and calculating the volume value based on the spliced point cloud data; The installation position of the stitching target (400) is located on the middle section (710), and is located in the effective scanning range when the laser scanner (100) scans at both ends of the middle section (710), and the effective scanning range is It is determined by the minimum grazing angle α between the generatrix of the cylindrical surface of the horizontal tank (700) and the laser beam of the laser scanner (100), and the angle between the laser beam and the generatrix is greater than/equal to the Minimum grazing angle α; The minimum grazing angle α=arctan(d/e), wherein, d is the diameter of the laser beam (110) of the laser scanner (100), and e is the measurement deviation value, and its unit is mm. 2. The large length-to-diameter ratio horizontal tank volume continuous laser scanning internal measurement device according to claim 1, characterized in that: the transmission assembly (300) includes a precision transmission wire rotatably arranged on the guide rail (200) A rod (310), a precision servo motor (320) fixed at one end of the guide rail (200) in the length direction and driving the precision transmission screw (310) to rotate, a slide block (330) is slidably arranged on the guide rail (200) ), the slider (330) is screwed on the precision transmission screw (310); the laser scanner (100) is arranged on the slider (330). 3. The large aspect ratio horizontal tank volume continuous laser scanning internal measurement device according to claim 2, characterized in that: the outside of the horizontal tank (700) is provided with a motor connected to the precision servo motor (320). A controller (500), the controller (500) controls the precision servo motor (320) to drive the laser scanner (100) to move equidistantly and intermittently; the data processor (600) is based on the The laser scanner (100) and the moving distance of the laser scanner (100) acquire point cloud data of the middle section (710) of the horizontal tank (700). 4. The large length-to-diameter ratio horizontal tank volume continuous laser scanning internal measurement device according to claim 1, characterized in that: the splicing target (400) is arranged in two groups at intervals along the length of the slide rail, and the splicing target (400) Multiple targets are included, and the multiple targets are located on different straight lines. 5. A large aspect ratio horizontal tank volume continuous laser scanning measurement method, using the large aspect ratio horizontal tank volume continuous laser scanning internal measurement device according to any one of claims 1-4, characterized in that: comprising The following steps: Step 1. Install one end of the guide rail (200) inside the horizontal tank (700) along the axial direction, and install the splicing target (400) in the horizontal tank (700), including the first end near the inlet end (720). a splicing target (410) and a second splicing target (420) near the bottom end (730); Step 2. Control the precision servo motor (320) to work, drive the laser scanner (100) to move into the horizontal tank (700), and when it is located at the interface between the inlet end (720) and the middle section (710), The laser scanner (100) scans the point cloud data of the inlet end (720), and the middle section (710) contains the point cloud data of the tank section where the first splicing target (410) is located; Step 3. Control the laser scanner (100) to move equidistantly and intermittently along the guide rail (200). After each movement stops, control the laser scanner (100) to scan for a circle along the axis of the vertical horizontal tank (700) to obtain the intermediate The three-dimensional point cloud data of the segment (710); Step 4. When the laser scanner (100) moves along the guide rail (200) to the interface between the bottom end (730) and the middle section (710), acquire the point cloud data of the bottom end (730), and the The middle section (710) contains point cloud data of the tank section where the second splicing target (420) is located; Step 5, splicing the point cloud data of the inlet port (720), the bottom end (730) and the middle segment (710); Step 6, calculating the volume based on the obtained point cloud data of the horizontal tank (700); The step of obtaining the three-dimensional point cloud data of the middle segment (710), comprising: Each time the laser scanner (100) stops moving, it acquires the two-dimensional point cloud data of the horizontal tank (700) in the circumferential direction, based on the distance value of each movement of the laser scanner (100) and the The two-dimensional point cloud data is spliced to form the three-dimensional point cloud data. 6. The continuous laser scanning measurement method for the volume of a horizontal tank with a large aspect ratio according to claim 5, characterized in that: the spliced point cloud of the inlet end (720), the bottom end (730) and the middle section (710) The step of data includes splicing the point cloud data of the entry port (720) and the middle section (710) based on the point cloud data of the entry port (720) and the point cloud data of the first splicing target (410) to form local points cloud data; Based on the point cloud data of the bottom end (730) and the point cloud data of the second stitching target (420), the point cloud data of the bottom end (730) and the local point cloud data are spliced to form the overall point of the horizontal tank cloud data. 7. The continuous laser scanning measurement method for large aspect ratio horizontal tank volume according to claim 5, characterized in that: the installation position of the splicing target (400) is located on the middle section (710), and is located on the The laser scanner (100) is within an effective scanning range when scanning at both ends of the middle section (710). 8. The continuous laser scanning measurement method for the volume of a large aspect ratio horizontal tank according to claim 7, wherein the step of determining the effective scanning range includes: Calculating the minimum grazing angle α, the minimum grazing angle α is the included angle between the generatrix of the cylindrical surface of the horizontal tank (700) and the laser light (110) of the laser scanner (100); Within the effective scanning range, the included angle between the laser beam of the laser scanner (100) and the generatrix of the cylindrical surface of the horizontal tank (700) is greater than or equal to the minimum grazing angle α. 9. The continuous laser scanning measurement method for the volume of a large aspect ratio horizontal tank according to claim 8, wherein the step of calculating the minimum grazing angle α includes: Obtain the diameter d of the laser beam (110) of the laser scanner (100), preset the measurement deviation value e, and the minimum grazing angle α=arctan (d/e); wherein, the diameter d, the measurement deviation value e The units are millimeters.

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