An Automatic Generation Method for 3D Models of Cross-Training Structures Based on GIM Technology

Abstract

The invention discloses a method for automatically generating a three-dimensional model of a spanning frame based on the GIM technology, comprising S1: using the unmanned aerial vehicle oblique photography technology to construct a terrain model within the width of a transmission line corridor, and providing geographic survey data for construction simulation; S2: using three-dimensional construction simulation software to establish a GIM model of the engineering body and a GIM model of a spanned object; S3: based on the model information of step S1 and step S2, using the three-dimensional construction simulation software to automatically generate an initial three-dimensional GIM model of the spanning frame; S4: performing manual intervention and scheme comparison on the automatically generated three-dimensional GIM model of the spanning frame, and outputting a final three-dimensional GIM model of the spanning frame; the invention can be combined with the GIM technology, can automatically generate a three-dimensional model of the spanning frame, and can effectively improve the efficiency and quality of preparing construction schemes.

Description

Technical Field

[0001] The invention relates to a method for automatically generating a three-dimensional model of a spanning frame based on a GIM technology, and belongs to the technical field of simulation of overhead power transmission lines. Background Art

[0002] With the continuous advancement of urbanization, the number of crossing situations encountered during the construction of power transmission and transformation projects is increasing. Crossing construction generally has the characteristics of tight schedule, high risk and great difficulty. In order to ensure safety, the construction plan of the crossing frame is generally adopted as an important protective measure. The existing construction plan of the crossing frame generally adopts a combination of manual experience and simplified calculation, which is difficult to accurately and comprehensively reflect the control points in the construction process. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for automatically generating a three-dimensional model of a spanning frame based on GIM technology, which can be combined with GIM technology to automatically generate a three-dimensional model of a spanning frame, and can effectively improve the efficiency and quality of construction plan preparation.

[0004] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0005] In a first aspect, the present invention provides a method for automatically generating a three-dimensional model of a spanning frame based on GIM technology, comprising:

[0006] S1: Use UAV oblique photography technology to construct a terrain model within the width of the transmission line corridor to provide geographic survey data for construction simulation;

[0007] S2: Use 3D construction simulation software to establish the GIM model of the project and the GIM model of the spanned object;

[0008] S3: Based on the model information of step S1 and step S2, a three-dimensional GIM model of an initial spanning frame is automatically generated using three-dimensional construction simulation software;

[0009] S4: Perform manual intervention and scheme comparison on the automatically generated three-dimensional GIM model of the span, and output the final three-dimensional GIM model of the span.

[0010] Furthermore, in step S1, the geographic survey data includes construction coordinates and construction elevations.

[0011] Furthermore, in step S2, the project body includes poles, towers, hardware, insulator strings, conductors and ground wires, and the object to be crossed includes at least one of a railway, a highway and a power line.

[0012] Furthermore, the step S1 includes the following process:

[0013] S11: Analyze the characteristics and requirements of the crossing section corridor, derive the performance and technical parameter requirements of the drone, and formulate an aerial photography plan;

[0014] S12: Collect data according to the aerial photography plan;

[0015] S13: preprocessing the collected data;

[0016] S14: Reconstructing a three-dimensional real scene model of the terrain according to the preprocessing result.

[0017] Furthermore, the aerial photography plan includes cruising altitude, route planning and camera installation angle indicators.

[0018] Furthermore, the data collected by the aerial photography scheme includes positioning data and image data; the preprocessing of the collected data includes precision positioning data, binding of image and positioning data, and correction of image data.

[0019] Furthermore, the step S14 includes image connection point extraction, image dense matching, regional block adjustment solution and aerial triangulation solution.

[0020] Furthermore, the step S2 includes:

[0021] S21: using 3D construction simulation software to establish a GIM model of the project and a GIM model of the spanned object, and output them in a GIM format file;

[0022] S22: unify the project GIM model, the spanned object GIM model and the oblique photography geographic survey data positioning benchmark in step S21, so that the coordinates of the project GIM model and the spanned object GIM model are consistent with the actual survey project coordinates;

[0023] S23: Importing the engineering entity GIM model and the spanning object GIM model into the three-dimensional real scene model and assembling them uniformly to construct a three-dimensional model of the overhead line crossing section.

[0024] Furthermore, the step S3 includes:

[0025] S31: Obtain the sag of the capping net of the spanning frame, the minimum safe distance between the lowest point of the sag and the spanned object, the terrain height difference and the height of the spanned object, and calculate the height value of the spanning frame;

[0026] S32: Calculate the windage value data of the conductor and the ground wire, obtain the maximum line side line spacing and the crossing angle, and calculate the length value of the crossing frame;

[0027] S33: Obtaining the horizontal distance between the inner edge of the spanning frame and the outer edge of the spanned object, the spanning frame position, and spanning frame parameters;

[0028] S34: Based on the above steps, automatically generate an initial spanning frame three-dimensional GIM model.

[0029] Furthermore, the spanning frame parameters include spanning frame material and specifications, load-bearing cable material and specifications, capping net material and specifications, and spanning frame vertical poles, crossbar spacing, scissors braces and guy wire arrangement erection rules.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] Aiming at the characteristics of large number of crossing and spanning projects, tight construction period, high risk and great difficulty, the present invention has developed a method for automatically generating three-dimensional models of crossing frames based on GIM technology based on the existing calculation method, erection rules and GIM technology of crossing frames. The method can output three-dimensional GIM models, CAD drawings and Word version calculation books of crossing frames, effectively improve the efficiency and quality of construction plan preparation, and can be used for technical briefing and training, significantly improving the inherent safety and management and control effectiveness of the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of a method for automatically generating a three-dimensional model of a spanning frame based on the GIM technology provided by an embodiment of the present invention;

[0033] Figure 2 It is a structural schematic diagram of a spanning frame facility provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0035] Example 1

[0036] This embodiment introduces a method for automatically generating a three-dimensional model of a spanning frame based on the GIM technology, including:

[0037] S1: Use UAV oblique photography technology to construct a terrain model within the width of the transmission line corridor to provide geographic survey data for construction simulation;

[0038] S2: Use 3D construction simulation software to establish the GIM model of the project and the GIM model of the spanned object;

[0039] S3: Based on the model information of step S1 and step S2, a three-dimensional GIM model of an initial spanning frame is automatically generated using three-dimensional construction simulation software;

[0040] S4: Perform manual intervention and scheme comparison on the automatically generated three-dimensional GIM model of the span, and output the final three-dimensional GIM model of the span.

[0041] Reference Figure 1 The present embodiment provides a method for automatically generating a three-dimensional model of a spanning frame based on the GIM technology, and its application process specifically involves the following steps:

[0042] S1. Use drone oblique photography technology to construct a terrain model within the width of the transmission line corridor to provide accurate geographic survey data of coordinates and elevations for construction simulation. In this embodiment, the specific line corridor path length is 1500m and the width is 200m;

[0043] S2. Use 3D construction simulation software to establish GIM models of poles, towers, hardware, insulator strings, conductors, and ground wires, as well as GIM models of railways, highways, and power lines;

[0044] S3. Based on the model information of terrain, engineering and spanned objects, and taking the relevant requirements in the regulations as boundary conditions, the calculation method and erection rules of the spanning frame position and size are edited into the 3D construction simulation software to realize the automatic generation of the initial spanning frame 3D GIM model;

[0045] S4. Perform manual intervention and scheme comparison on the automatically generated 3D model of the span, and output the final 3D GIM model of the span, CAD drawings, and Word version calculation book. Combining the traditional construction scheme preparation method with GIM technology, the 3D model of the span can be automatically generated, which can effectively improve the efficiency and quality of construction scheme preparation, and can be used for technical disclosure and training, which helps to improve the inherent safety of the project and the effectiveness of management and control.

[0046] The method provided by the present invention mainly includes four parts, namely: constructing a real-scene terrain model, establishing a GIM model of the engineering body and the spanned object, automatically generating a three-dimensional model of the spanning frame, and exporting the results. The following describes these four parts in detail.

[0047] 1. Constructing a real-scene terrain model, step S1 specifically includes the following contents:

[0048] S11. Analyze the characteristics and requirements of the crossing section corridor, derive the specific performance and technical parameter requirements of the drone, and then formulate a detailed aerial photography plan including cruising altitude, route planning, and camera installation angle indicators;

[0049] In this embodiment, the specific requirements for drone aerial photography are: the data sampling interval of the airborne GPS receiver during flight is no more than 1s, the flight ascent and descent speed is no more than 10m / s; the heading overlap is 60% to 65%, the lateral overlap is set to 30% to 35%, and the route curvature is no more than 3%; the same altitude is maintained during flight, the altitude difference between adjacent images on the same route is no more than 820m, and the difference between the maximum altitude and the minimum altitude is no more than 30m; the heading coverage should exceed the boundary line of the shooting area by no less than one baseline, and the lateral coverage should exceed the boundary line of the shooting area by no less than 50% of the image frame;

[0050] S12. Select favorable weather conditions and collect data according to the aerial photography plan to ensure that the details of the terrain and landforms can be truly displayed;

[0051] S13, preprocessing the collected image data and positioning data, the preprocessing including positioning data refinement, image and positioning data binding, and image data correction;

[0052] S14. Reconstruct the three-dimensional real-scene model of the terrain through the steps of image connection point extraction, image dense matching, regional network adjustment solution, and aerial triangulation solution, so as to provide an accurate terrain model for subsequent construction simulation.

[0053] 2. Establish the GIM model of the project body and the spanned object. Step S2 specifically includes the following contents:

[0054] S21. Use 3D construction simulation software to build the GIM model of the project and the model of the object to be crossed, and output it in a unified GIM format file for application. The hierarchical division and model accuracy of the GIM model construction should meet the needs of construction simulation, while taking into account the lightweight processing of the model to improve the speed of software loading the model;

[0055] In this embodiment, the specific angle steel towers on both sides of the span are 5E1-SZKK1, with a call height of 45m and a tower height of 61m; the conductor adopts 4×LGJ-630 / 45 steel core aluminum stranded wire with a diameter of 33.8mm; the width of the secondary highway being spanned is 8m, and the roadbed height is 1m; the span span is 200m, the spanned highway is located in the middle of the span section, and the span angle is 90 degrees;

[0056] S22. Determine and unify the positioning benchmarks of the GIM model and the oblique photography geographic survey data. The coordinates of the GIM model should be consistent with the coordinates of the actual survey project. When imported into the 3D construction simulation software, the coordinates must be automatically checked and matched to ensure the real-life restoration of the project model and the geographic survey data.

[0057] S23. Based on the geographic survey data in S1 and the three-dimensional real-life terrain model constructed by oblique photography, the GIM model of the project body and the GIM model of the crossed object are imported, and the two are assembled uniformly to construct a three-dimensional model of the crossing section of the overhead line.

[0058] The step of arranging the object to be crossed in step S23 includes:

[0059] (a) Select key points of the path of the feature on the oblique photography terrain, use the set of key points on the path as the data basis, and calculate the smooth curve coordinate point set through the Hermite curve formula. The smoothness of the curve can be adjusted by modifying the distance between points.

[0060] (b) The three-dimensional construction simulation software has built-in unit-length models of railways, highways, and power lines. According to the smooth curve coordinate point set, it automatically fills in the extended grid data between two adjacent points and adapts to the generated mapping data, thereby generating a complete curved railway, highway, and power line model;

[0061] (c) Modify and adjust the size parameters of the object, and synchronize the mesh data vertex displacement algorithm to restore and generate a ground object model of the corresponding size, and obtain the height of the object being crossed.

[0062] 3. Automatically generate a three-dimensional model of the spanning frame. Step S3 specifically includes the following contents:

[0063] S31. Determine the sag of the capping net of the spanning frame and the minimum safe distance between the lowest point of the sag and the railway, highway, or power line spanning object according to the regulations and specifications, and calculate the spanning frame height in combination with the terrain height difference and the height of the spanning object;

[0064] In this embodiment, the secondary highway roadbed is 1m high, and the regulations and specifications require that the distance between the road surface and the lowest point of the capping net sag of the crossing frame is not less than 6m, the capping net sag is 0.5m, and the terrain height difference at the crossing frame erection is 3.5m, then the crossing frame height h≥1+6+0.5+3.5=11m, and in this embodiment, the crossing frame height h=12m;

[0065] S32. Calculate the windage values ​​of the conductor and ground wire according to the regulations and specifications, and then calculate the length of the crossing frame based on the maximum line edge spacing and the crossing angle.

[0066] In this embodiment,

[0067] (1) Calculation of wind load per meter of conductor at wind speed of 10 m / s

[0068] w 4(10) =0.0613Kd=0.0613×1.1×33.8=2.3N / m

[0069] Where:

[0070] w 4(10) ——Wind load per unit length of the construction line conductor or ground wire under installation meteorological conditions (wind speed 10m / s), unit N / m;

[0071] K——wind load type coefficient: d<17mm, K=1.2; d>17mm, K=1.1;

[0072] d——Diameter of conductor or ground wire, take 40mm.

[0073] (2) Calculation of conductor windage

[0074]

[0075] Where:

[0076] Z x ——The wind deviation distance of the conductor at the crossing point under the installation meteorological conditions, in meters;

[0077] x——horizontal distance from the spanned object to the tower adjacent to the construction line, taken as 100m;

[0078] H——horizontal pay-off tension, take 21000N;

[0079] l——The span of the construction line across the span is 200m;

[0080] λ——The length of the hanging insulator string or pulley hanger at both ends of the construction line crossing, which is 5m;

[0081] w1——weight per unit length of the construction line conductor, taken as 21N / m.

[0082] (3) Calculation of span length

[0083] Take 24m

[0084] Where:

[0085] L——span length, in m;

[0086] α——crossing angle, (unit: °);

[0087] Z x ——The wind deviation distance of the conductor or ground wire at the crossing point under the installation meteorological conditions, in meters;

[0088] b – The horizontal width between the outermost conductor and ground wire of the construction line protected by the crossing frame at the crossing point in the transverse direction of the construction line, which is 15m;

[0089] C——1.5 for power outage crossing, 2.0 for non-power outage crossing, unit: m;

[0090] The center line of the crossing frame should coincide with the center line of the shielding width.

[0091] S33, determining the horizontal distance between the inner edge of the spanning frame and the outer edge of the spanned object according to the regulations and specifications, and then determining the position of the spanning frame;

[0092] In this embodiment, according to the requirements of regulations and specifications, the horizontal distance between the inner edge of the crossing frame and the roadside is 3m, and the number of longitudinal rows of crossing frame poles is 4, thereby determining the position of the crossing frame.

[0093] S34. Determine the material and specifications of the spanning frame, the material and specifications of the load-bearing cables and capping nets, the spacing between spanning frame uprights and crossbars, and the rules for the arrangement and erection of scissor braces and guy wires according to the structural requirements of the regulations and specifications;

[0094] In this embodiment, the material of the spanning frame is bamboo. According to the regulations and specifications, the diameter of the small head of the effective part of the vertical pole, large cross bar and scissor brace is not less than 75mm, the diameter of the small head of the effective part of the small cross bar is not less than 90mm, the distance between the vertical pole and the cross bar is 1.2m, and the scissor brace and the guy wire are set every 6m. The guy wire adopts a 10mm diameter steel wire rope, and the angle with the ground is 45 degrees. The load-bearing rope adopts 4 Dyneema ropes with a diameter of 16mm, 2 for each left and right loop.

[0095] S35. Edit the above calculation method or construction requirements into the three-dimensional construction simulation software, and automatically generate the initial three-dimensional model of the spanning frame by combining the model information of the terrain, the project body and the spanned object.

[0096] 4. Export of results, such as Figure 1 to Figure 2 shown.

[0097] This part corresponds to step S4. According to engineering experience, manual intervention and scheme comparison are carried out on the automatically generated initial spanning frame 3D model, and the final spanning frame 3D GIM model is determined and output. The Word version of the calculation book and CAD drawings (including main view, top view, left view, 3D schematic diagram) are output simultaneously, which can effectively improve the efficiency and quality of construction plan preparation and can be used for technical disclosure and training.

[0098] The schematic diagram of the spanning frame structure in the present invention is as follows Figure 2 As shown, 1 represents the horn, 2 represents the load-bearing cable, 3 represents the scissors brace, 4 represents the large crossbar, 5 represents the vertical pole, 6 represents the small crossbar, 7 represents the guy wire, 8 represents the ground anchor, 9 represents the highway, and 10 represents the capping net.

[0099] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for automatically generating a three-dimensional model of a spanning frame based on GIM technology. It is characterized in that include: S1: Use UAV oblique photography technology to construct a terrain model within the width of the transmission line corridor to provide geographic survey data for construction simulation; S2: Use 3D construction simulation software to establish the GIM model of the project and the GIM model of the spanned object; S3: Based on the model information of step S1 and step S2, the initial spanning frame three-dimensional GIM model is automatically generated using three-dimensional construction simulation software; step S3 includes: S31: Obtain the sag of the capping net of the spanning frame, the minimum safe distance between the lowest point of the sag and the spanned object, the terrain height difference and the height of the spanned object, and calculate the height value of the spanning frame; S32: Calculate the windage value data of the conductor and the ground wire, obtain the maximum line side line spacing and the crossing angle, and calculate the length value of the crossing frame; S33: Obtaining the horizontal distance between the inner edge of the spanning frame and the outer edge of the spanned object, the spanning frame position, and spanning frame parameters; S34: Based on the above steps, automatically generate an initial spanning frame three-dimensional GIM model; S4: Perform manual intervention and scheme comparison on the automatically generated three-dimensional GIM model of the span, and output the final three-dimensional GIM model of the span.

2. The method for automatically generating a three-dimensional model of a spanning frame based on GIM technology according to claim 1, Features: In step S1, the geographic survey data includes construction coordinates and construction elevations.

3. The method for automatically generating a three-dimensional model of a spanning frame based on GIM technology according to claim 1, Features: In step S2, the project body includes poles, towers, hardware, insulator strings, conductors and ground wires, and the object to be crossed includes at least one of a railway, a highway and a power line.

4. The method for automatically generating a three-dimensional model of a spanning frame based on GIM technology according to claim 1, It is characterized in that The step S1 includes the following process: S11: Analyze the characteristics and requirements of the crossing section corridor, derive the performance and technical parameter requirements of the drone, and formulate an aerial photography plan; S12: Collect data according to the aerial photography plan; S13: preprocessing the collected data; S14: Reconstructing a three-dimensional real scene model of the terrain according to the preprocessing result.

5. The method for automatically generating a three-dimensional model of a spanning frame based on GIM technology according to claim 4, It is characterized in that The aerial photography plan includes cruising altitude, route planning and camera installation angle indicators.

6. The method for automatically generating a three-dimensional model of a spanning frame based on GIM technology according to claim 4, It is characterized in that The data collected by the aerial photography solution includes positioning data and image data; the preprocessing of the collected data includes precision positioning data, binding of image and positioning data, and correction of image data.

7. The method for automatically generating a three-dimensional model of a spanning frame based on GIM technology according to claim 4, It is characterized in that The step S14 includes image connection point extraction, image dense matching, regional block adjustment solution and aerial triangulation solution.

8. The method for automatically generating a three-dimensional model of a spanning frame based on GIM technology according to claim 4, It is characterized in that The step S2 comprises: S21: Use 3D construction simulation software to establish the GIM model of the project and the GIM model of the spanned object, and output them in GIM format files; S22: unify the project GIM model, the spanned object GIM model and the oblique photography geographic survey data positioning benchmark in step S21, so that the coordinates of the project GIM model and the spanned object GIM model are consistent with the actual survey project coordinates; S23: Importing the engineering entity GIM model and the spanning object GIM model into the three-dimensional real scene model and assembling them uniformly to construct a three-dimensional model of the overhead line crossing section.

9. The method for automatically generating a three-dimensional model of a spanning frame based on GIM technology according to claim 1, It is characterized in that The parameters of the spanning frame include the material and specification of the spanning frame, the material and specification of the load-bearing cable, the material and specification of the capping net, and the erection rules of the spanning frame vertical poles, crossbar spacing, scissors braces and guy wire arrangements.

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