Curved surface control line identification method based on laser scanning

Abstract

The invention relates to a curved surface control line identification method based on laser scanning, and the method comprises the steps: employing a flexible plastic plate as a bearing object of a scanning identification point, enabling the flexible plastic plate to deform along with the surface shape of an identified object, and enabling the flexible plastic plate to be well pasted; in addition, the scanning identification point adopts a structure with a thick middle part and a thin edge, so that the identification device has certain rigidity, can adapt to a curved surface and is attached along with the surface shape; the device is simple in manufacturing material, low in cost and convenient to install, error influences caused by manual reading and equipment misoperation can be reduced, the linear measurement precision and efficiency are greatly improved, production manufacturing and bridge site on-site erection are effectively guided, the product quality is further improved, and the overall project construction period is shortened.

Description

Technical Field

[0001] The invention relates to the technical field of bridge plate processing, and in particular to a curved surface control line recognition method based on laser scanning. Background Art

[0002] In the production process of steel structure bridge projects, the bridge alignment measurement scheme is a technical method used by engineers when producing, building and maintaining bridges. The purpose is to measure the geometric parameters of the bridge to ensure that the bridge meets the design requirements and is safe and reliable. The steps of the commonly used bridge alignment measurement scheme are as follows:

[0003] 1. First, you need to determine the measurement scope and parameters to be measured, such as bridge length, width, height, curvature, arch, etc.

[0004] 2. Select appropriate measuring instruments according to the parameters to be measured, such as total station, laser rangefinder, tape measure, etc.

[0005] 3. Set measurement control points at key locations of bridge beam sections to determine the measurement benchmark and coordinate system.

[0006] 4. Conduct on-site measurements and record data based on the parameters and control points that need to be measured.

[0007] 5. Import the measured data into computer software for data processing and calculation to obtain the geometric parameters of the bridge.

[0008] 6. Draw a bridge line diagram based on the calculation results to guide subsequent production, construction and maintenance work.

[0009] For projects with high requirements for linear accuracy, due to the influence of human and equipment accuracy, the measurement efficiency and accuracy of some parameters are low. A control line identification method based on laser scanning is proposed. The laser scanning equipment is used to efficiently and accurately extract the control points on the surface of the object, and the control line is accurately analyzed and drawn in the computer software. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide a surface control line recognition method based on laser scanning, which can solve the problem of poor precision control of general bridge steel profile lines.

[0011] In order to solve the above technical problems, the technical solution of the present invention is: a surface control line recognition method based on laser scanning, and its innovation lies in: the specific recognition method is as follows:

[0012] S1: Scribe control lines on the surface of the scanned object;

[0013] S2: Align the center line of the identification device with the control line and fix it;

[0014] S3: laser scanning the surface of the object;

[0015] S4: Identify the identification devices at both ends of the control line in the identification software, each device displays an identification circle, and the algorithm is used to identify the center of the circle;

[0016] S5: In the recognition software, the center of the circle is perpendicular to the plane of the recognition circle and vertically downward to identify the thickness of the device, and the center of the surface of the object to be recognized is calculated;

[0017] S6: In the recognition software, the line connecting the centers of the two ends of the identified object surface is the control line to be scanned and identified;

[0018] S7: If the surface of the object to be identified is a curved surface, the control line is also a curve. It is only necessary to draw the normal line and the tangent line on the curve according to the control points, and then attach the identification device to the object to be identified. The line connecting the centers of all the surface circles is the fitting control line.

[0019] Furthermore, the identification device in S2 includes a flexible plastic plate, a magnetic layer and an adhesion layer; the magnetic layer is connected to the flexible plastic plate through the adhesion layer, and the magnetic layer is applied to the surface of the steel object; a cross mark center line is set on the flexible plastic plate, and a scanning identification point is set at the position of the cross mark center line, and the center of the scanning identification point coincides with the intersection of the cross mark center line; the scanning identification point is a structure that is thick in the middle and thin at the edges.

[0020] The advantages of the present invention are:

[0021] 1) In the present invention, a flexible plastic plate is used as a carrier of the scanning identification point. The flexible plastic plate can be deformed according to the surface shape of the object to be identified and can be well attached. In addition, the scanning identification point adopts a structure with a thick middle and thin edges, so as to maintain a certain rigidity of the identification device and adapt to the curved surface and attach it according to the surface shape. The device is made of simple materials, low cost, and easy to install. It can reduce the error caused by manual reading and improper operation of the equipment, greatly improve the accuracy and efficiency of linear measurement, effectively guide production and manufacturing and on-site erection of the bridge site, further improve product quality, and shorten the overall project period. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0023] Figure 1 This is a flow chart of a method for identifying curved control lines based on laser scanning according to the present invention.

[0024] Figure 2 The invention discloses a plane reference control recognition method of a curved surface control line recognition method based on laser scanning.

[0025] Figure 3 The invention discloses a curved surface reference control identification method of a curved surface control line identification method based on laser scanning.

[0026] Figure 4 This is a structural diagram of an identification device for a curved surface control line identification method based on laser scanning according to the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] like Figures 1 to 4 A surface control line recognition method based on laser scanning is shown, and the specific recognition method is as follows:

[0030] S1: Scribe control lines on the surface of the scanned object;

[0031] S2: Align the center line of the identification device with the control line and fix it;

[0032] S3: laser scanning the surface of the object;

[0033] S4: Identify the identification devices at both ends of the control line in the identification software, each device displays an identification circle, and the algorithm is used to identify the center of the circle;

[0034] S5: In the recognition software, the center of the circle is perpendicular to the plane of the recognition circle and vertically downward to identify the thickness of the device, and the center of the surface of the object to be recognized is calculated;

[0035] S6: In the recognition software, the line connecting the centers of the two ends of the identified object surface is the control line to be scanned and identified;

[0036] S7: If the surface of the object to be identified is a curved surface, the control line is also a curve. It is only necessary to draw the normal line and the tangent line on the curve according to the control points, and then attach the identification device to the object to be identified. The line connecting the centers of all the surface circles is the fitting control line.

[0037] The identification device in S2 includes a flexible plastic plate 1, a magnetic layer and an adhesion layer; the magnetic layer is connected to the flexible plastic plate 1 through the adhesion layer, and the magnetic layer is applied to the surface of the steel object; a cross mark center line 3 is set on the flexible plastic plate 1, and a scanning identification point 2 is set at the position of the cross mark center line 3, and the center point 2 of the scanning identification point coincides with the intersection of the cross mark center line 3; the scanning identification point 2 is a structure that is thick in the middle and thin at the edges.

[0038] Those skilled in the art should understand that the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and improvements, and these changes and improvements shall all fall within the scope of the present invention claimed for protection.

Claims

1. A method for identifying curved surface control lines based on laser scanning, characterized in that: The specific identification method is as follows: S1: Scribe control lines on the surface of the scanned object; S2: Align the center line of the identification device with the control line and fix it; S3: laser scanning the surface of the object; S4: Identify the identification devices at both ends of the control line in the identification software, each device displays an identification circle, and the algorithm is used to identify the center of the circle; S5: In the recognition software, the center of the circle is perpendicular to the plane of the recognition circle and vertically downward to identify the thickness of the device, and the center of the circle on the surface of the object to be recognized is calculated; S6: In the recognition software, the line connecting the centers of the surfaces of the objects to be recognized at both ends is the control line of the location to be scanned and recognized; S7: If the surface of the object to be identified is a curved surface, the control line is also a curve. It is only necessary to draw the normal line and the tangent line on the curve according to the control points, and then attach the identification device to the object to be identified. The line connecting the centers of all the surface circles is the fitting control line.

2. The method for identifying curved control lines based on laser scanning according to claim 1, characterized in that: The identification device in S2 includes a flexible plastic plate, a magnetic layer and an adhesive layer; the magnetic layer is connected to the flexible plastic plate through the adhesive layer, and the magnetic layer is applied to the surface of the steel object; a cross mark center line is set on the flexible plastic plate, and a scanning identification point is set at the position of the cross mark center line, and the center of the scanning identification point coincides with the intersection of the cross mark center line; the scanning identification point is a structure with a thick middle and thin edges.

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