A tower crane rapid layout method based on welzl algorithm

Abstract

The application discloses a tower crane rapid layout method based on a Welzl algorithm, reads a field plan, extracts coordinate data of a building main body contour and a land red line range from the field plan, constructs a building vertex set P which needs to be covered by the tower crane and a position point set A which allows the tower crane to be laid out based on the coordinate data, calculates a minimum enclosing circle C according to the point set P through the Welzl algorithm i , judges whether a radius of the minimum enclosing circle C i is less than or equal to a working radius R t of the tower crane to be laid out, removes all points in the point set P if C i ≤ R t , records and outputs a tower crane position, and if C i >R t , then through a loop until all building vertices in the point set P are covered by the working radius of the tower crane, the loop can be completed, and a tower crane layout position is output. The application determines the best layout position of the tower crane by automatically calculating the minimum enclosing circle of the building, thereby rapidly and accurately covering all building areas which need to be constructed, improves construction efficiency, and has important practical application value.

Description

Technical Field

[0001] The present invention relates to the field of building construction, and in particular to a tower crane rapid deployment method based on the Welzl algorithm. Background Art

[0002] Crane placement is crucial in the early stages of a project. Proper crane placement can effectively improve construction efficiency and safety. Existing crane placement methods often rely on manual experience and simple geometric calculations, making it difficult to quickly and accurately determine crane positions within complex building layouts, thus hindering construction efficiency. Especially when buildings are irregularly shaped and crane coverage is limited, quickly and accurately positioning cranes to cover all areas requiring construction becomes a pressing issue. Summary of the Invention

[0003] The object of the present invention is to provide a method for quickly deploying a tower crane based on the Welzl algorithm, comprising the following steps:

[0004] S1. Read the site plan in dxf format and extract the coordinate data of the building outline and land red line range from it;

[0005] S2. Based on the coordinate data of the building outline and the land red line range, construct the building vertex set P that the tower crane needs to cover and the location point set A where the tower crane is allowed to be deployed;

[0006] S3. Calculate the minimum enclosing circle C based on the point set P using the Welzl algorithm i , determine the minimum enclosing circle C i Is the radius less than or equal to the working radius R of the tower crane to be deployed? t ;The initial value of i is 1;

[0007] If C i ≤R t , then remove all points in the point set P, record the crane position, and jump to step S8;

[0008] If C i >R t , then proceed to step S4;

[0009] S4, determine the minimum enclosing circle C i The two building vertices on the i1 and Z i2 ; Connect building vertex Z i1 , Z i2 , recorded as auxiliary line L i12 ;

[0010] Z i1 , Z i2 is the center of the circle, R tDraw auxiliary circle N with radius i1 , i2 , Determine intersection point of auxiliary circle N i1 , i2 and auxiliary line L i12 , respectively recorded as J i1 , J i2 ;

[0011] Determine whether auxiliary circle N i1 coincides with the working range of the erected tower crane, if so, go to step S6, if not, go to step S5;

[0012] S5, determine the allowed tower crane erection point T i1 inside N i1 closest to J i1 , and the allowed tower crane erection point T i2 inside N i2 closest to J i2 ;

[0013] Erect the tower crane with T i1 , T i2 as the center and R t as the radius;

[0014] S6, determine the allowed tower crane erection point T i1 inside N i1 farthest from the erected tower crane and closest to J i1 , and the allowed tower crane erection point T i2 inside N i2 farthest from the erected tower crane and closest to J i2 ;

[0015] Erect the tower crane with T i1 , T i2 as the center and R t as the radius;

[0016] S7, remove the building vertex covered by the working radius of the erected tower crane from the point set P to obtain a new point set P, let i=i+1, repeat steps S3-S7 until all building vertices in the point set P are covered by the working radius of the erected tower crane;

[0017] S8, output the tower crane erection position.

[0018] Further, in step S1, read the plan by dxfgrabber library, and obtain the coordinate data of the building main body contour and land red line by dxf.entities respectively.

[0019] Further, in step S2, the step of constructing the set P of building top points to be covered and the set A of position points allowing the arrangement of the tower crane comprises:

[0020] 1) Coordinate data of the building main contour and the land red line range are origin processed, and then all coordinate points within the land red line range are rasterized to obtain a plurality of data points;

[0021] 2) Data points located outside the building main contour, at a distance of d1-d2m from the building main body and within the land red line are retained;

[0022] 3) Data points with a distance less than or equal to hm from the building corner are deleted, and the retained data points are used to construct the set A of points allowing the arrangement of the tower crane;

[0023] 4) The coordinates of the building top points are extracted to obtain the set P of building top point coordinates to be covered.

[0024] Further, the values of d1, d2 and h are determined by the actual requirements of the construction site.

[0025] Further, d1=3, d2=5, and h=8.

[0026] Further, in step S3, the minimum enclosing circle C i is a circle covering all building top points and having the minimum radius.

[0027] Further, in step S4, when the number of building top points on the minimum enclosing circle C i is greater than 2, the two building top points farthest apart are selected as Z i1 and Z i2 .

[0028] Further, in step S6, when the number of loops is greater than 1, to prevent the tower crane from colliding in actual operation, the positions of T i1 and T i2 are regions not covered by the working radius of the arranged tower crane.

[0029] Further, the value of k in step S6 is the anti-collision distance, and k=2m.

[0030] Further, in step S8, the tower crane arrangement position is visualized after being output.

[0031] The technical effects of the present application are self-evident, and the beneficial effects of the present application are as follows:

[0032] The present invention proposes a method for rapid tower crane deployment based on the Welzl algorithm. By automatically calculating the minimum enclosing circle of a building, the optimal deployment position of the tower crane is determined, thereby quickly and accurately covering all building areas that require construction, improving construction efficiency, and having important practical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a flow chart of Example 11;

[0034] Figure 2 This is a schematic diagram of the crane deployment point data set A obtained after data processing;

[0035] Figure 3 This is a schematic diagram of the first cycle of tower crane deployment;

[0036] Figure 4 This is the schematic diagram of the second cycle of tower crane layout, which is also the final layout diagram. DETAILED DESCRIPTION

[0037] The present invention will be further described below with reference to the following examples, but it should not be understood that the scope of the present invention is limited to the following examples. Without departing from the above technical ideas of the present invention, various substitutions and modifications can be made according to common technical knowledge and customary means in the art, and all should be included in the scope of protection of the present invention.

[0038] Example 1:

[0039] A tower crane rapid deployment method based on the Welzl algorithm comprises the following steps:

[0040] S1. Read the site plan in dxf format and extract the coordinate data of the building outline and land red line range from it;

[0041] S2. Based on the coordinate data of the building outline and the land red line range, construct the building vertex set P that the tower crane needs to cover and the location point set A where the tower crane is allowed to be deployed;

[0042] S3. Calculate the minimum enclosing circle C based on the point set P using the Welzl algorithm i , determine the minimum enclosing circle C i Is the radius less than or equal to the working radius R of the tower crane to be deployed? t ;The initial value of i is 1;

[0043] If C i ≤R t , then remove all points in the point set P, record the crane position, and jump to step S8;

[0044] If C i >R t , then proceed to step S4;

[0045] S4, determine the minimum enclosing circle C i The two building vertices on the i1 and Z i2 ; Connect building vertex Z i1 、Z i2 , recorded as auxiliary line L i12 ;

[0046] Z i1 、Z i2 is the center of the circle, R t Draw a helper circle with radius N i1 、N i2 , determine the auxiliary circle N i1 、N i2 With auxiliary line L i12 The intersection points are denoted as J i1 、J i2 ;

[0047] Determine auxiliary circle N i1 Whether it overlaps with the working range of the deployed tower crane. If so, proceed to step S6; if not, proceed to step S5;

[0048] S5. Determine the location of N i1 Inside and at distance J i1 The nearest permitted crane deployment point, denoted as T i1 , and located in N i2 Inside and at distance J i2 The nearest permitted crane deployment point, denoted as T i2 ;

[0049] T i1 、T i2 is the center of the circle, R t Arrange tower crane for radius;

[0050] S6. Determine the location of N i1 Internal, and deployed tower crane (working scope and N i1 Overlapping deployed cranes) with a distance greater than k and a distance J i1 The nearest permitted crane deployment point, denoted as T i1 , and located at N i2 Internal, and deployed tower crane (working scope and N i2 Overlapping deployed cranes) with a distance greater than k and a distance J i2 The nearest permitted crane deployment point, denoted as T i2 ;

[0051] T i1 、T i2 is the center of the circle, R t Arrange tower crane for radius;

[0052] S7. Remove the building vertices covered by the working radius of the deployed tower crane from the point set P to obtain a new point set P. Let i = i + 1, and repeat steps S3 to S7 until all building vertices in the point set P are covered by the working radius of the deployed tower crane.

[0053] S8. Output the tower crane layout location.

[0054] Example 2:

[0055] The main structure of this embodiment is the same as that of embodiment 1. Furthermore, in step S1, the plan view is read through the dxfgrabber library, and the coordinate data of the building outline and the land red line are respectively obtained through dxf.entities.

[0056] Example 3:

[0057] The main structure of this embodiment is the same as any one of Embodiments 1 to 2. Furthermore, in step S2, the steps of constructing a vertex set P of buildings that the tower crane needs to cover and a location point set A where the tower crane is allowed to be deployed include:

[0058] 1) Perform origin processing on the coordinate data of the building outline and the land red line range (i.e., determine the minimum X, Y coordinate value among all the coordinate data and use it as the origin (0, 0), and perform corresponding X, Y movement on the remaining coordinate points). Then, perform raster processing on all coordinate points within the land red line range to obtain multiple data points;

[0059] 2) Keep data points outside the main building outline, d1-d2m away from the main building, and within the land boundary;

[0060] 3) Delete the data points whose distance to the building's yin and yang corners is less than or equal to hm, and use the remaining data points to construct the point set A where crane points can be placed;

[0061] 4) Extract the vertex coordinates of the building and obtain the point set P of the vertex coordinates of the building that needs to be covered.

[0062] Example 4:

[0063] The main structure of this embodiment is the same as that of embodiment 3. Furthermore, the values ​​of d1, d2 and h are determined by the actual needs of the construction site.

[0064] Example 5:

[0065] The main structure of this embodiment is the same as any one of Embodiments 3 to 4, and further, d1=3, d2=5, and h=8.

[0066] Example 6:

[0067] The main structure of this embodiment is the same as any one of the embodiments 1 to 5. Further, in step S3, the minimum enclosing circle C i Refers to the circle with the smallest radius that covers all building vertices.

[0068] Example 7:

[0069] The main structure of this embodiment is the same as any one of the embodiments 1 to 6. Further, in step S4, when the minimum enclosing circle C i When the number of building vertices on the Z axis is greater than 2, the two building vertices with the farthest distance are selected as Z i1 and Z i2 .

[0070] Example 8:

[0071] The main structure of this embodiment is the same as any one of the embodiments 1 to 7. Furthermore, in step S6, when the number of cycles is greater than 1, in order to prevent the tower crane from colliding during actual operation, T i1 、T i2 The location is an area not covered by the established tower crane working radius.

[0072] Example 9:

[0073] The main structure of this embodiment is the same as any one of Embodiments 1 to 8. Furthermore, the value k in step S6 is the anti-collision distance, k=2m.

[0074] Example 10:

[0075] The main structure of this embodiment is the same as any one of Embodiments 1 to 9. Furthermore, in step S8, the tower crane layout position is output and then visualized.

[0076] Example 11:

[0077] The main structure of this embodiment is the same as any one of Embodiments 1 to 10. Furthermore, the present invention provides a tower crane rapid deployment method based on an improved Welzl algorithm, comprising the following steps:

[0078] S1. Drawing reading

[0079] SS1. Read the site dxf format plan;

[0080] SS2. Extract x and y data such as the main building outline and land boundary, and normalize all data to their origins.

[0081] S2. Data Processing

[0082] SS1. Rasterize the coordinate points within the land red line with an accuracy of 1m;

[0083] SS2. After rasterization, pre-process the data points to ensure they meet the following requirements: 1. They are within the land boundary and 2. They are outside the main building outline.

[0084] SS3. Under normal circumstances, to ensure that the tower crane is properly attached to the main structure, it is necessary to retain data points within 3-5 meters from the main building.

[0085] SS4. To ensure the requirements for tower crane disassembly, rotation, and standardized attachment, delete the data points within 8 meters of the building's corners to obtain the points where tower crane deployment is allowed.

[0086] SS5. Extract building vertex coordinates;

[0087] SS6. Get the data, the building vertex set P that needs to be covered and the point set A where tower cranes are allowed to be deployed.

[0088] S3. Procedure for arranging tower crane:

[0089] SS1. Apply Welzl algorithm for tower crane layout:

[0090] SS2. Based on the point set P, the minimum enclosing circle Ci (i = 1, 2, ...) is quickly calculated using the Welzl algorithm.

[0091] SS3. Determine whether the radius of Ci is less than or equal to the radius of the tower crane to be deployed, Rt:

[0092] SS4. If yes, directly cover all points in P and remove them, and record the position of the tower crane.

[0093] SS5. If not, find points Z1 and Z2 on the minimum enclosing circle Ci, and draw auxiliary lines Z1Z2 and the minimum enclosing circle Ci.

[0094] SS6. Draw auxiliary circles N1 and N2 with Z1 and Z2 as the centers and Rt as the radius.

[0095] SS7. Find the intersection points J1 and J2 of N1, N2, and Z1Z2, and determine whether J1 and J2 are inside the minimum enclosing circle Ci:

[0096] SS8. If yes, find point T1 inside N1 and closest to J1, and point T2 inside N2 and closest to J2. Deploy the crane with T1 and T2 as the center and Rt as the radius.

[0097] SS9. Remove the points in P that are covered by existing cranes to obtain a new point set P;

[0098] SS10. Repeat the above steps until there are no more points left in P;

[0099] SS11. In the subsequent loop, it should be noted that in order to prevent the possibility of tower crane collision in actual operation, step SS8 is updated to find point T1 inside N1, outside the deployed tower crane (the anti-collision distance can be increased according to actual use) and closest to J1, and point T2 inside N2, outside the deployed tower crane and closest to J2, and deploy the tower crane with T1 and T2 as the center and Rt as the radius.

[0100] S4. Output and visualize the tower crane layout location.

[0101] Furthermore, the steps are all implemented using Python language;

[0102] Furthermore, the site plan is saved in .dxf format, and the name of the building outline layer in the plan is set as required, and the building outline should include the outline of all building components;

[0103] Furthermore, the plan is read through the dxfgrabber library, and the coordinate points of the building outline and the land red line are respectively obtained through dxf.entities;

[0104] Furthermore, to ensure the normal attachment of the tower crane, the distance between the data point and the main building can be modified according to the actual situation;

[0105] Furthermore, to ensure the requirements for tower crane disassembly, rotation and standardized attachment, tower cranes are not allowed to be arranged at the corners of buildings and the distance can be modified according to actual conditions;

[0106] Furthermore, the radius Rt of the tower crane to be deployed can be modified according to actual conditions;

[0107] Furthermore, the correctness of the Welzl algorithm is based on a theorem: for any n points on a plane, take the n+1th point outside its minimum covering circle. Then the n+1th point must be on the minimum covering circle of these n+1 points. The Welzl algorithm has a significant advantage in calculating the minimum enclosing circle.

[0108] Furthermore, the above steps are only analyzed based on the example of two P midpoint sets on the enclosing circle obtained by the Welzl algorithm. If there are three points on the minimum enclosing circle obtained by the Welzl algorithm, the two points with the farthest distance can be selected by calculation to carry out the above tower crane layout process.

Claims

1. A tower crane rapid deployment method based on the Welzl algorithm, characterized in that: The following steps are involved: S1. Read the site plan in dxf format and extract the coordinate data of the building outline and land red line range from it; S2. Based on the coordinate data of the building outline and the land red line range, construct the building vertex set P that the tower crane needs to cover and the location point set A where the tower crane is allowed to be deployed; S3. Calculate the minimum enclosing circle C based on the point set P using the Welzl algorithm i , determine the minimum enclosing circle C i Is the radius less than or equal to the working radius R of the tower crane to be deployed? t ;The initial value of i is 1; If C i ≤R t , then remove all points in the point set P, record the crane position, and jump to step S8; If C i >R t , then proceed to step S4; S4, determine the minimum enclosing circle C i The two building vertices on the i1 and Z i2 ; Connect building vertex Z i1 , Z i2 , recorded as auxiliary line L i12 ; Z i1 , Z i2 is the center of the circle, R t Draw a helper circle with radius N i1 、N i2 , determine the auxiliary circle N i1 、N i2 With auxiliary line L i12 The intersection points are denoted as J i1 、J i2 ; Determine auxiliary circle N i1 Whether it overlaps with the working range of the deployed tower crane. If so, proceed to step S6; if not, proceed to step S5; S5. Determine the location of N i1 Inside and at distance J i1 The nearest permitted crane deployment point, denoted as T i1 , and located in N i2 Inside and at distance J i2 The nearest permitted crane deployment point, denoted as T i2 ; T i1 、T i2 is the center of the circle, R t Arrange tower crane for radius; S6. Determine the location of N i1 Internal, distance from the deployed crane is greater than k and distance J i1 The nearest permitted crane deployment point, denoted as T i1 , and located at N i2 Internal, distance from the deployed crane is greater than k and distance J i2 The nearest permitted crane deployment point, denoted as T i2 ; T i1 、T i2 is the center of the circle, R t Arrange tower crane for radius; S7. Remove the building vertices covered by the working radius of the deployed tower crane from the point set P to obtain a new point set P. Let i = i + 1, and repeat steps S3 to S7 until all building vertices in the point set P are covered by the working radius of the deployed tower crane. S8. Output the tower crane layout location.

2. The tower crane rapid deployment method based on the Welzl algorithm according to claim 1, characterized in that: In step S1, the plan is read through the dxfgrabber library, and the coordinate data of the building outline and the land red line are obtained through dxf.entities.

3. The tower crane rapid deployment method based on the Welzl algorithm according to claim 1, characterized in that: In step S2, the steps of constructing the building vertex set P that the tower crane needs to cover and the location point set A where the tower crane is allowed to be deployed include: 1) The coordinate data of the building outline and the land red line range are processed into origins, and then all coordinate points within the land red line range are rasterized to obtain multiple data points; 2) Keep data points outside the main building outline, d1-d2m away from the main building, and within the land boundary; 3) Delete the data points whose distance to the building's yin and yang corners is less than or equal to hm, and use the remaining data points to construct the point set A where crane points can be placed; 4) Extract the vertex coordinates of the building and obtain the point set P of the vertex coordinates of the building that needs to be covered.

4. The tower crane rapid deployment method based on the Welzl algorithm according to claim 3, characterized in that: The values ​​of d1, d2 and h are determined by the actual needs of the construction site.

5. The tower crane rapid deployment method based on the Welzl algorithm according to claim 3, characterized in that: d1=3, d2=5, h=8.

6. The tower crane rapid deployment method based on the Welzl algorithm according to claim 1, characterized in that: In step S3, the minimum enclosing circle C i Refers to the circle with the smallest radius that covers all building vertices.

7. The tower crane rapid deployment method based on the Welzl algorithm according to claim 1, characterized in that: In step S4, when the minimum enclosing circle C i When the number of building vertices on the Z axis is greater than 2, the two building vertices with the farthest distance are selected as Z i1 and Z i2 .

8. The tower crane rapid deployment method based on the Welzl algorithm according to claim 1, characterized in that: In step S6, when the number of cycles is greater than 1, in order to prevent the tower crane from colliding during actual operation, T i1 、T i2 The location is an area not covered by the established tower crane working radius.

9. The tower crane rapid deployment method based on the Welzl algorithm according to claim 1, characterized in that: The k value in step S6 is the anti-collision distance, k=2m.

10. The tower crane rapid deployment method based on the Welzl algorithm according to claim 1, characterized in that: In step S8, after the tower crane layout position is output, the tower crane layout position is visualized.

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