JP2012138022A - Method and device for generating cross section diagram under power transmission line - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate the tree height line on the ground along a cross section line in a direction indicated on a planar map, in an easy and highly accurate manner.SOLUTION: Points, which divide a cross section line indicated in a direction perpendicular to the span direction in which a power transmission line is stretched in a longitudinal direction at designated interpolation intervals, are set as attention points, and the area of a retrieval range consisting of a circle of a retrieval radius around each attention point is set. (a) A plurality of apices in the retrieval range are determined from a triangle mesh data having three-dimensional coordinates for triangle apices in the triangle mesh with triangles set on an x-y planar map connected with each other, (b) a value zp in the height direction at the attention point is determined by interpolation calculation shown by zp=(w1×zq1+w2×zq2+...+wn×zqn), where height values of the plurality of apices are zq1, zq2, ..., zqn and weights inversely proportional to respective distances from the attention points to the apices in the retrieval range are w1, w2, ...,wn (w1+w2+...+wn=1), and (c) the tree height line is generated by using the determined heights of the respective attention points.

Description

The present invention relates to a technique for processing 3D map data acquired from, for example, aerial photographs, and more particularly to a transmission line lower cross-sectional view generation method and system for generating a cross section under a transmission line from 3D map data.

  Patent Document 1 discloses a method for creating a target sectional view using CAD technology from 3D map data acquired by a plotter.

  In Patent Document 1, (a) an interpolation parameter including an interpolation interval, a search radius, and a weight is input, (b) a planar map is displayed using the input three-dimensional map data, and (c) the planar map. Generating one or more parallel second cross-sectional positions on both sides of the cross-sectional position designated on the display screen of (1), (d) each cross-section of the first and second cross-sectional positions from the three-dimensional map data (E) Among the extracted terrain data, the search radius of the search radius centered on the point of interest obtained by dividing the first cross-sectional position in the length direction by the interpolation interval is extracted. Zq1, Zq2,..., Zqn are the values in the height direction of the terrain data at each point in the search range consisting of circles, and the weights inversely proportional to the respective distances from the point of interest to each point in the search range w1, w2,..., wn (w1 + w2 +... + wn = 1) Is obtained by interpolation calculation represented by Zp = (w1 · Zq1 + w2 · Zq2 + ... + wn · Zqn). .

  In Patent Document 1, it is possible to generate and output a cross-sectional view showing a change in ground height at a specified cross-sectional position with high accuracy. However, a change in the height of a feature such as a tree or a building on the ground along the cross-sectional position cannot be displayed.

  Therefore, for example, when checking whether a tree or building near the transmission line is kept at an appropriate distance without touching the transmission line, the worker actually visits the site and It was necessary to check the height of the building.

Patent Document 2 discloses a power transmission line under trouble tree display device that automatically identifies and notifies trouble trees. In Patent Document 2,
-When the span of the route on which the transmission line is stretched is specified from the three-dimensional data, the tree information and the tower position of the transmission line are read from the database, and the transmission line and the tree position connecting the towers To determine the separation distance from
The separation distance on any of the xy axis plane (plane), xz axis plane (vertical plane), and yz axis plane (horizontal plane) is within a few weeks or months. Displaying that it is close to the power line more than a predetermined amount,
-Update tree information by calculating the growth of trees from the date and growth rate and adding this growth to the z value of the tree information in the database;
Is disclosed.

  In FIG. 6B of Patent Document 2, a line (tree height line) indicating the height of the tree is shown in the cross section between the spans on which the transmission lines are stretched. However, Patent Document 2 does not describe a tree line generation method. In addition, there is no disclosure of a method for generating a sectional view including a ground height line in a direction perpendicular to the span direction in which the transmission line is stretched or a tree height line indicating a change in the height of the tree.

Japanese Patent No. 3267589 Japanese Patent No. 3714017

  In Cited Documents 1 and 2, the section line indicated in the direction perpendicular to the span direction in which the transmission line is stretched, or the tree line on the ground along the section line indicated in an arbitrary direction on the plane map There is a problem that it cannot be generated easily and with high accuracy.

  Therefore, the present invention provides a method and an apparatus for generating a cross-sectional view under a transmission line that can easily and accurately generate a tree line on the ground along a cross-sectional line in an arbitrary direction indicated on a planar map. The purpose is to do.

  In order to solve the above-described problem, a method for generating a lower cross-sectional view of a power transmission line according to the present invention displays an xy plane map using input three-dimensional map data, and displays the plane map on the display screen. Generating a ground height line representing a change in the ground height along the cross-sectional line indicated in a direction perpendicular to the span direction in which the transmission line is stretched, and the height of the tree on the ground along the cross-sectional line A tree line representing the change in height is generated.

  Preferably, in the step of generating the tree line, (a) a circle having a search radius centered on each point of interest is a point obtained by dividing the section line in the length direction by a specified interpolation interval. (B) three-dimensional coordinates (x, y, z) for the vertices of each triangle in the triangular mesh that connects the triangles set on the xy plane map to each other A plurality of vertices within the search range are determined from the triangular mesh data having the following: (c) the height values of the plurality of vertices are set as zq1, zq2,. .., Wn (w1 + w2 +.・ Zqn) Is determined by interpolation calculations, using the height of each point of interest is determined (d), it generates the tree height line.

  Alternatively, the step of generating the tree line comprises: (a) three-dimensional coordinates (x, y, x, y) for the vertices of each triangle in a triangular mesh connecting the triangles set on the xy plane map to each other; z) to determine a plurality of intersections where the cross-section line and the triangle mesh intersect, and (b) the heights at the vertices of the sides of the triangle on the triangle mesh where the intersection exists. By proportionally allocating the difference according to the ratio of the distance on the xy plane between the vertices at both ends and the distance on the xy plane between one of the vertices at both ends and the intersection, A height is determined, and (c) the tree line is generated using the determined heights of the plurality of intersections.

  The step of generating the ground height line includes: (a) x and y coordinates of a plurality of first intersection points where the section line and the contour line intersect, and a second intersection point where the section line and the feature intersect. x, y coordinates are extracted from the three-dimensional map data, (b) the height at the first intersection point is determined to be equal to the contour line, and (d) the height at the second intersection point is determined as the second intersection point. A height difference between two first intersections adjacent to the two intersections, a distance on the xy plane between the two first intersections, one of the two first intersections, and the second (E) the height of the first intersection and the height of the plurality of second intersections determined by proportionally allocating according to the ratio with the distance on the xy plane between the intersections Is used to generate a ground height line representing a change in ground height along the cross-sectional line.

  According to the present invention, the operator designates a cross section line to be measured on the display screen of the planar map displayed using the three-dimensional map data, thereby automatically obtaining necessary terrain data, triangular mesh from the three-dimensional map data. Based on the data extracted, a high-precision tree height line can be generated and output in addition to the ground height line along the desired section line. Furthermore, accompanying information related to this can be output in a simple procedure.

  In addition, the ground height on the section line is calculated by proportional distribution calculation using the value of the contour line that intersects the section line, and the tree height line on the ground height line is calculated at each point arranged in a triangular mesh shape. It is possible to calculate easily and with high accuracy by retransmission calculation or proportional distribution calculation using x, y, and z coordinate values.

  Furthermore, based on the three-dimensional map data, a sectional view including the position and height of the building that intersects the sectional line can be obtained.

  According to the present invention, it is possible to easily and accurately generate a tree height line on the ground along a cross-sectional line designated on a planar map.

The block diagram which shows the structure of the system which concerns on one Embodiment of this invention. The flowchart which shows the transmission line lower cross-sectional view production | generation procedure which concerns on this embodiment. The figure which shows an example of a plane map. The figure which shows the cross-sectional line instruct | indicated on the plane map, and the example of the expanded cross-sectional line. The figure which shows the example of the intersection of the cross section line determined in order to produce | generate a ground height line, a contour line, and a feature. The figure for demonstrating the height calculation of an intersection. The figure which shows the triangular mesh arrange | positioned on a plane map. The figure which showed the triangular mesh shown in FIG. 7 three-dimensionally using the height of each point. The figure which shows the example of the intersection of a triangular mesh and the designated cross section line. Figure intersections J ₁ through J ₅ the triangular mesh and the cross-section line shown schematically. The figure which shows the example of a display of sectional drawing containing a ground height line and a tree height line. The figure which shows the example of the cross-sectional line instruct | indicated on the plane map in which a building is scattered. The figure which shows the example of a display of sectional drawing containing a ground height line and the line which shows the change of the height of a building. The flowchart which shows the other power transmission line lower cross-sectional view production | generation procedure. The figure for demonstrating the production | generation method of the tree line using the interpolation calculation.

  Hereinafter, embodiments of the present invention will be described. First, an example of a technique which is a premise of the present invention will be described. In order to acquire map data from aerial photographs, an apparatus called a charter (substance mapper) has been developed. The plotter is an apparatus that creates a stereoscopic image in which a pair of aerial photographic films, for example, 60% overlapped on each other, are placed on a photographic stand and are individually observed with the left and right eyes through eyepieces. Specifically, a projector is first installed on the aerial photographic film on the photographic stand with a relative positional relationship similar to the relative positional relationship of the camera at the time of shooting with respect to the aerial photographic film. A similar stereoscopic image is reproduced. This operation is called relative orientation.

  After this mutual orientation, the process moves to absolute orientation. In absolute orientation, on the display screen of the display that displays the three-dimensional image of the aerial photographic film by inputting the coordinate point x, y and the reference point of the height (elevation value) z into the data acquisition system in the plotter The reference point on the display screen is matched with the reference point in the stereoscopic image. These orientation operations are performed using observation markers (female marks) determined by the plotter.

  In plotting, three or more reference points whose x, y, and z are known are required in the model to be plotted. For this purpose, an anti-air sign is installed so that the ground reference point can be seen on the aerial photograph, and the reference point is added to each model based on this. This operation is called aerial triangulation, and analysis calculation is performed using a computer.

  The mapping of aerial photographs of roads, buildings, etc. is performed by touching a target to be plotted and acquiring point data for each changing point such as a corner. Contour lines are automatically acquired at arbitrary designated intervals by moving the measurement target by touching the ground portion on the aerial photograph.

  In this way, acquisition of three-dimensional map data having three-dimensional coordinates, so-called digital mapping is performed, and a drawing is made. Digital mapping means analog information of a ready-made map and various additional information (terrain, land use type, etc.) digitized and recorded on an electronic storage medium, and reproduced and output as a topographical map figure from the electronic storage medium ( Work on the construction of a new digital topographic map systematically organized by computer technology by measuring map information related to topography and features in digital format by the Ministry of Construction (Geographical Survey Institute) or aerial photogrammetry Including the creation of original maps such as topographic maps (according to the digital mapping work procedure in the Ministry of Construction Public Survey Work Regulations).

  The three-dimensional map data having the three-dimensional coordinates (x, y, z) obtained by this digital mapping is taken into the three-dimensional CAD system and edited as a drawing according to the required specifications. Lines and symbols determined by the Ministry of Construction cannot be handled only by the basic performance of the CAD system, and can be handled by adding new functions to the CAD system through customization.

  This customization is roughly classified into two types, one for editing and one for application. The present invention relates to customization of the latter application in particular. Hereinafter, an embodiment of the present invention will be described based on the above matters.

  FIG. 1 shows a system configuration according to an embodiment of the present invention. This system is roughly divided into a plotting machine 1, a CAD system 2 and an automatic drafting machine 9, which are connected by a bus 10. In the figure, various interfaces are omitted.

  The plotter 1 is as described above. The aerial photographic film 11 is placed on a photo frame, projected as a stereoscopic image with a projector (mutual orientation), and further subjected to absolute orientation, and then a three-dimensional map. Get the data.

  The three-dimensional map data has terrain and features in the aerial photograph having x, y coordinate values and height values z. For example, a feature such as a building has x and y coordinates and a height value (elevation value) of the highest point (elevation point) of the feature. On the other hand, in a planar map (two-dimensional map), a feature has x and y coordinate values but does not have a height value (elevation value) z.

  In the single section measurement procedure of this embodiment, a sectional view including a ground height line indicating a change in ground height on the designated section line and a line indicating a tree height on the section line and a change in the height of the building is generated. And output.

  The tree height and the height of the building are measured from an aerial photograph using the plotter 1, for example. On the xy plane, a triangular mesh (see FIG. 7) represented as a set of mutually connected triangular faces is arranged. The x and y coordinate values and the height z are measured using the plotter 1 for the vertices of each triangle in the triangle mesh. Therefore, the measured points of the height z are set in the triangular mesh at equal intervals or at arbitrary intervals (for example, 5 to 10 m). Here, data including coordinate values (x, y) and height values (z) for each point (each vertex of each triangle) set in a triangular mesh shape on the xy plane map is represented as triangular mesh data. Call. Triangular mesh data is created and stored as part of the data of the three-dimensional map data.

  Since the x and y coordinates of the triangular mesh and the x and y coordinates of the plane map are measured from the same aerial photograph, they coincide with each other. Accordingly, as shown in FIG. 7, a triangular mesh can be arranged on the xy plane map, and the height (elevation) corresponding to the x and y coordinate values corresponding to each point of the triangular mesh on the plane map. Is obtained. FIG. 8 shows the triangular mesh shown in FIG. 7 three-dimensionally using the height of each point of the triangular mesh.

  The three-dimensional map data created by the plotter 1 is input to the CAD system 2 and stored in the main storage device 4 and / or the external storage device 5 in FIG.

  The CAD system 2 is configured using a general-purpose computer, and specifically includes a CPU 3, a main storage device 4 such as a ROM and a RAM, an external storage device 5 such as an HDD (hard disk drive), a keyboard and a pointing device (for example, a mouse). 3D map data input from the plotter 1 is edited as map data according to the required specifications. The map data created by the CAD system 2 is output as a paper-based map by the automatic drafting machine 9.

  Here, the CAD system 2 calculates the height of the ground, tree height, building, etc. at the indicated cross-sectional position according to the transmission line lower cross-sectional view generation program set as one of the application programs based on the present invention. Then, a process of displaying as a single sectional view on the display 7 or outputting as a paper-based single sectional view 12 via the automatic drafting machine 9 is performed. This transmission line lower cross-sectional view generation program is installed in the external storage device 5 in advance, and is downloaded to the main storage device 4 from here and used.

  Hereinafter, the transmission line lower cross-sectional view generation procedure based on the transmission line lower cross-sectional view generation program will be described with reference to the flowchart shown in FIG. First, various parameters relating to the generation of the lower cross section of the transmission line are input (step S11). The parameters include, for example, parameters necessary for generating the vertical and horizontal scales of the cross-sectional view, the reference elevation value H, a tree line to be described later, and the like.

  Next, the 3D map data is fetched from the plotter 1 (step S12). The captured 3D map data is stored in the main storage device 4 or the external storage device 5. Next, an xy plane map 20 as shown in FIG. 3 is displayed on the display 7 using the x and y data of the captured three-dimensional map data (step S13).

  Then, on the display screen of the planar map 20, the operator designates a cross-sectional position 21 where a cross-sectional view is desired to be generated (step S14). Specifically, by using a pointing device such as a mouse included in the input device 6 to indicate both end points a and b of the line (cross-sectional line) that becomes the cross-sectional position 21 on the display screen on the planar map 20. The cross section line 21 is indicated in a direction perpendicular to the diameter of the path through which the power transmission line is provided. The instructed section line 21 is displayed on the display screen of the planar map 20, whereby the operator can confirm the instructed section line (section position) 21. Here, the cross-sectional line is designated in the direction perpendicular to the diameter, but the present invention is not limited to this, and the method according to the present embodiment can be applied even if the cross-sectional line is designated in any direction. It is.

  Next, terrain data intersecting with the instructed section line 21 is extracted from the three-dimensional map data, and a line indicating the change in the height of the ground along the section line 21 (ground height line) is used. ) Is generated. In addition, a line indicating a change in the height of the tree (tree height) on the section line and the height of the building is generated.

  First, generation of the ground height line on the section line 21 will be described.

  The both ends a and b of the designated section line 21 are expanded to extend the section line longer. As shown in FIG. 4, both ends of the new cross-sectional line after extension are a ′ and b ′. Hereinafter, cross-sectional lines having both ends a ′ and b ′ are represented as cross-sectional lines (a ′ and b ′). A cross-sectional line having both ends a and b is represented as a cross-sectional line (a, b).

From the position (x, y) of the cross-sectional line (a ′, b ′) and the position (x, y) of the contour line and the feature such as road, river, railway, etc., the cross-sectional line (a ′, b ′) Intersections with intersecting contour lines and features are determined (step S16). For example, as shown in FIG. 5, the intersections I _{1 to} I ₅ between the cross-sectional lines (a ′, b ′) and the contour lines or the features are determined.

In step S17, the coordinates (x _n , y _n , z _n ) of each intersection (for example, I _{1 to} I ₅ ) are determined (n is an index for identifying each intersection, and for example, n = 1, 2, ..., 5). The x and y coordinate values for each intersection are extracted from the topographic data of the three-dimensional map data. The value of the contour line is extracted from the three-dimensional map data as the height z of the intersection between the cross-section line (a ′, b ′) and the contour line. The height z of the intersection point with features such as roads, rivers, and railways that cannot be extracted from the three-dimensional map data is calculated using the values of the contour lines.

In FIG. 5, the height of the intersection (for example, I ₁ , I ₃ , etc. ₎ between the cross-sectional line and the contour line is the value of the contour line. Further, as shown in FIG. 6, the height of the intersection (for example, I ₂ ) of the feature that cannot be extracted from the three-dimensional map data is adjacent to the intersection I ₂ on the sectional line (height has been determined). ) In consideration of the slope between the intersections I ₁ and I ₃ , the calculation is performed as follows.

In FIG. 6, the coordinates of the intersection point I ₁ are (x ₁ , y ₁ , z ₁ ), and the coordinates of the intersection point I ₃ are (x ₃ , y ₃ , z ₃ ). Here, the x, y and z coordinate values of the intersections I ₁ and I _{3 and} the x and y coordinate values of the I ₂ are determined as described above. Therefore, the z coordinate of the intersection I ₂ is expressed by the equation (1). The difference in z-coordinate value between I ₁ and I ₃ is expressed as follows: the distance on the xy plane between I ₁ and I ₃ and the distance on the xy plane between I ₁ and I ₂ It can be obtained by proportionally allocating according to the ratio.

  The z coordinates of the end points a and b of the cross section line are also calculated in the same manner as described above, using the x, y, and z coordinates of two intersecting points that are adjacent on the cross section line (height values have been determined).

After determining the intersection points I _{1 to} I ₅ and the x, y, and z coordinate values of the end points a and b of the cross section line as described above, the midpoint or the start point a on the cross section line is set to the reference point (0, 0), the distance from the reference point is calculated for each of the intersections I _{1 to} I ₅ . The intersections I _{1 to} I ₅ and the end points a and b of the cross-sectional line are arranged in order from the smallest distance. Using the height (z) of each of the arranged points, a ground height line 101 indicating a change in ground height along the section line 21 is generated. The generated ground height line 101 is displayed on the display 7 as shown in FIG. 11, and is further output on paper by the automatic drafting machine 9 (step S18).

  Next, the height (tree height, etc.) of a feature such as a tree or a building existing on the ground along the instructed section line is calculated, and a tree height line is generated. Here, first, a first method for generating a tree line will be described.

  In step S21, the triangular mesh data of the xy area corresponding to the currently displayed planar map is read from the three-dimensional map data stored in the main storage device 4 or the external storage device 5 in step S12, and the triangular mesh is read out. And the intersection of the triangular mesh and the cross section line 21 is determined from the position of the cross section line 21 instructed in step S14 (see FIG. 9).

Then, (x, y, z) of each determined intersection is calculated in the same manner as in the case of the ground height (step S22). FIG. 10 schematically shows the intersections J _{1 to} J ₆ between the triangular mesh and the cross section line 21. As described above, the triangular mesh data has a height z in addition to the x and y coordinates of each vertex of the triangle. Therefore, when the intersection coincides with the triangle vertex of the triangular mesh, the (x, y, z) of the intersection is determined as the (x, y, z) value of the vertex included in the triangle mesh data.

The x and y coordinate values of the intersections between the section line 21 and the triangle sides of the triangular mesh (for example, the intersections J _{1 to} J _{6 in} FIG. 10) are extracted from the three-dimensional map data. The heights of these intersections are calculated using the (x, y, z) values of the two end points (vertices) of the side where the intersection is located.

For example, since the intersection point J ₂ is on a side _whose ends are the vertices O ₂ and O ₃ of the triangular mesh, the height of the intersection point J ₂ is the x, y, and z of the _two vertices O ₂ and O _3. And can be calculated as follows:

The coordinates of the vertex O ₂ are (x _o2 , y _o2 , z _o2 ), the coordinates of the vertex O ₃ are (x _o3 , _{yo 3} , z _o3 ), and the coordinates of the intersection J ₂ are (x _J2 , y _J2 , z _J2 ) The z-coordinate z _J2 of the intersection J ₂ is expressed by the difference of the z-coordinate value between O ₂ and O ₃ as shown in the following formula (2), and the xy plane between O ₂ and O _3. It can be obtained by proportionally allocating according to the ratio of the upper distance and the distance on the xy plane between O ₂ and O _J2 .

The heights of other intersections J ₁ , J ₃ , J ₄ , J ₅ and J ₆ can be calculated in the same manner as the intersection J ₂ . That is, for example, in the case of the intersection J ₃ , the x, y, and z coordinate values of the vertices O ₃ and O ₄ are used. If the x, y and z coordinate values of O ₂ and O _{3 in} the above equation (2) are replaced with the x, y and z coordinate values of the vertices O ₃ and O ₄ , the height of the intersection J ₃ can be calculated. In the case of the intersection J ₄ , the x, y, and z coordinate values of the vertices O ₄ and O ₅ are used. X of O _2, O ₃ in the above expression (2), y, vertex z coordinate value O _4, O ₅ of x, y, replaced by z-coordinate value, the coordinate of the intersection J ₄ instead of the intersection J ₂ ( x _J4 , y _J4 , z _J4 ), the height of the intersection J ₄ can be calculated.

  After determining the x, y, and z coordinate values of each intersection as described above, the distance from the reference point is calculated for each intersection using the midpoint or starting point a on the cross-section line as the reference point (0, 0). To do. Then, the intersections are arranged in order from the smallest distance. Using the height of each of the arranged points, a line 102 indicating a change in the height of a tree or a building along the cross-sectional line 21 is generated. As shown in FIG. 11, the generated line 102 indicating the height change of a tree or a building is output so as to overlap the ground height line 101 output in step S18 (step S23).

  The procedure for generating and outputting a line representing the change in the height of trees and buildings as described above is effective in, for example, an area where trees and buildings exist almost continuously. The present invention can also be applied to an area where buildings are scattered in a place where there is little change in height. In the case of the latter (ie, an area where buildings are scattered, for example), a line representing a height change can be generated and output by the following procedure.

  For example, it is assumed that the section line 21 is instructed on a planar map of an area where buildings as shown in FIG. 12 are scattered. As described above, the ground height line 201 is generated and output in steps S15 to S18.

  Next, from the position (x, y) of the section line 21 and the position (x, y) of each building, a building that intersects the section line 21 (for example, buildings 40, 41, and 42 in FIG. 12) The intersection of the building and the section line 21 is determined.

  In FIG. 12, the number of vertices of the figure of the building 40 (here, 8) and the coordinates (x, y, z) of the vertices c1 to c8 are extracted from the three-dimensional map data. The intersections of the building 40 and the section line 21 are 51 and 52. The (x, y) of each intersection is calculated from the coordinates (x, y, z) of the vertex of the building 40. Since the intersection 51 is on the side [c1, c2], the x, y coordinates of the intersection 51 are calculated from the x, y coordinates of the vertex c1 and the x, y coordinates of the vertex c2. Since the intersection 52 is on the side [c5, c6], the x and y coordinates of the intersection of the intersection 52 are calculated from the x and y coordinates of the vertex c5 and the x and y coordinates of the vertex c6.

  The three-dimensional map data includes x, y, and z values of the highest point (elevation point) of the building for one building. For example, in FIG. 12, the elevation points are H0 to H3. In order to determine which elevation point is a point inside the building of interest (for example, building 40 in this case), the following processing is performed.

  In FIG. 12, elevation points H0 and H3 in the vicinity thereof are detected from the coordinate values of the vertices of the building 40. Then, it is determined whether the elevation point is on the right side or the left side with respect to the traveling direction of each side of the building 40, and the case where the elevation point is on the right side and the case on the left side are counted. However, when a vertical line is dropped from the elevation point to each side, the side where there is no intersection with the vertical line is not counted.

  For example, in the case of the building 40, the traveling direction of the side [c1, c2] is the direction from c1 to c2 as shown in FIG. 12, and the traveling direction of the side [c5, c6] is shown in FIG. As shown, the direction is c5 to c6. Therefore, the elevation point H0 is on the right side of the traveling direction of the side [c1, c2], the side [c6, c7], the side [c7, c8], and the side [c8, c1], but the elevation point H0 is on the left side. There is no such side. Similarly, the elevation point H3 is on the right side with respect to the traveling direction of the side [c1, c2], but on the left side with respect to the traveling direction of the side [c7, c8].

That is,
In the case of the elevation point H0, the “right” count number = 4 and the “left” count number = 0.
In the case of the elevation point H3, the “right” count number = 1, the “left” count number = 1.
It is.

  If “Right” count> 0 and “Left” count = 0, or “Right” count = 0 and “Left” count> 0, the elevation point is in the building Otherwise, it can be determined that the elevation point is outside the building. Therefore, it can be determined that the elevation point H0 is inside the building 40 and the elevation point H3 is outside the building 40.

  As described above, the height of the building 40 is determined as the z value (elevation value) of the elevation point H0. Similarly to the case of the building 40, the height z of the other buildings 41 and 42 intersecting the section line 21 is determined as the z value (elevation value) of the elevation points H1 and H2.

  As described above, after determining (x, y, z) of the intersection with the section line 21 for each building, the center point or starting point a on the section line is used as the reference point (0, 0) for each building. Calculate the distance from the reference point. Then, as shown in FIG. 13, the rectangles representing the buildings (202a corresponding to the building 40, 202b corresponding to the building 41, 202c corresponding to the building 42) are arranged on the ground height line 201 in order from the smallest distance. . The width of the rectangle representing the building corresponds to the length of the section line 21 passing through the building (that is, the distance between two intersections between the building and the section line), and the height of the rectangle is as described above. Corresponds to the determined height of the building.

  The added sectional views of the generated building heights 202 a to 202 c are displayed on the display 7 as shown in FIG. 13, and further outputted on paper by the automatic drafting machine 9.

  Along the transmission line, the distance between the transmission line and the trees or buildings needs to be maintained appropriately. According to the present embodiment, for example, when the instructed cross-sectional line 21 crosses the power transmission line as shown in FIG. 3, the range in which the power transmission line fluctuates due to the position (height) of the power transmission line, wind, or the like. Is also displayed in addition to the sectional view (see FIGS. 11 and 13). With such a display, it can be easily confirmed visually whether or not an appropriate separation distance is maintained between the transmission line and the tree or building.

  Information related to the transmission line (for example, tower number, tower coordinates and height (x, y, z), type of transmission line, transmission power, coordinates of the center point of the horizontal deflection of the bottom wire, etc.) is 3D map data Included. In addition, the horizontal oscillation of the transmission line is displayed as a semicircle centered on the point that becomes the center of deflection of the lowermost electric wire in the cross section of the tower. The radius (separation) of this semicircle depends on the type of the transmission line in advance. This is a predetermined value, and this value may also be stored in the main storage device 4 and the external storage device 5 in advance.

  As shown in FIG. 11 and FIG. 13, when displaying the horizontal cross section of the transmission line together with the ground height line and tree height line, for example, in step S <b> 11 of FIG. 2, the user sets the transmission voltage or the transmission voltage. Enter parameters such as the distance from the corresponding transmission line, tower number, and line width of the transmission line. Thereby, as described above, the ground height line and the tree height line (or the height line on the building) are generated and displayed, and the horizontal oscillation sections 103 and 203 of the transmission line intersecting the designated section line 21 are mainly displayed. It generates based on the information stored in the storage device 4 and the external storage device 5, and displays it as shown in FIG. 12 and FIG. 13 (step S31).

  Further, the separation distance between the power transmission line and the tree or building is displayed along with the separation lines (104, 204) in the sectional views as shown in FIGS. 12 and 13 (step S32). The separation distance can be calculated by determining the x and y coordinates of the transmission lines, trees and buildings included in the three-dimensional map data, and the height z as described above.

  Next, a second method for generating a tree line on the ground along the designated section line will be described.

  The tree line generated according to the first method described above has higher accuracy as the number of vertices per unit area on the triangular mesh increases. For example, if there are cliffs, roads, rivers, etc. on the topography along the cross-sectional line instructed in step S14, if there is a large change in ground height (Z value), the tree height will also change accordingly. . The greater the number of vertices per unit area on the triangular mesh, the more rapid changes in tree height that accompany this large change in ground height can be reflected in the tree height line. However, the greater the number of vertices per unit area, the more time is required to measure the height of each vertex.

  In the first method, the height z of the intersection between the cross-sectional line and the triangular mesh is calculated using the heights of the two vertices adjacent to the intersection. On the other hand, in the second method, the height z of a plurality of points (for example, the height should be obtained) on the cross-sectional line (for example, the intersection of the designated cross-sectional line and the triangular mesh) is set to a plurality of points around the target point. A tree line can be generated with high accuracy by obtaining the height of a point (vertex or elevation point of a triangular mesh) by interpolation calculation. According to this second method, even if the number of vertices per unit area of the triangular mesh (or the number of points whose reference height value is known) is not so large, the ground height changes as described above. Tree height lines that accurately represent the accompanying tree height changes can be generated.

  FIG. 14 shows a transmission line lower cross-sectional view generation procedure when the second method for generating a tree line is used. Steps S21 and S22 in FIG. 2 are replaced with step S20 in FIG. In the following, the parts of FIG. 14 that are different from FIG. 2 will be described.

  First, in step S11, an interpolation parameter including an interpolation interval d, a search radius r, and a weight w is input. Hereinafter, the process of step S20 will be described with reference to FIG.

  As shown in FIG. 15, the points obtained by dividing the section line 21 in the length direction by the interpolation interval d are set as the attention points, and the value z in the height direction at each attention point is calculated by interpolation calculation. In this case, first, triangular mesh data of the xy region corresponding to the currently displayed planar map is read from the three-dimensional map data stored in the main storage device 4 or the external storage device 5.

In FIG. 15, when calculating the height of the point of interest p on the cross section line 21, a search range 141 of radius r is set around the point p, and the vertex q within the search range 141 is set from the triangular mesh data. To decide. The z value of the intersection point p is calculated from the z values of the vertices q (for example, four vertices O ₄ , O ₅ , O ₆ , and O _{7 in this case} ) of n triangular meshes within the search range 141 by interpolation. To do. In this interpolation calculation, a weight w inversely proportional to the distance from the intersection point p is given to the z value of the vertex.

  This interpolation calculation is expressed by the following formula.

zp = (w1 · zq1 + w2 · Zq2 + ... + wn · zqn) Equation (3)
Here, zp is a z value to be obtained for the intersection point p, zq1, zq2,..., Zqn are z values of n vertices q within the search range, and w1, w2,. Is a weight (weight coefficient) inversely proportional to each distance to the point q, and w1 + w2 +... + Wn = 1. That is, a larger weight is given to the z value of the point q closer to the point p.

  After determining the x, y, and z coordinate values of each attention point as described above, in step S23, the reference point (0, 0) is used as the reference point (0, 0) for each attention point. Calculate the distance from the point. Then, the attention points are arranged in order from the smallest distance. Using the height of each point of interest arranged, a line 102 indicating a change in the height of a tree, a building, or the like along the cross-sectional line 21 is generated. As shown in FIG. 11, the generated tree height line 102 is superimposed on the ground height line 101 output in step S18 and is output (step S23).

In the above description, the points obtained by dividing the section line 21 in the length direction by the interpolation interval d are determined as the attention points, and the value in the height direction of the attention point is calculated by interpolation calculation. The method of determining the attention point to be obtained is not limited to this case. For example, each intersection of the cross section line and the triangular mesh may be determined as a point of interest, and the value in the height direction of the point of interest may be calculated by interpolation calculation. In this case, an interpolation parameter including at least the search radius r and the weight w is input in step S11 of FIG. In step S20, first, as in the case of the ground height, a triangle is obtained from the triangular mesh of the xy region corresponding to the currently displayed planar map and the position of the cross section line 21 instructed in step S14. The intersection of the mesh and the cross section line 21 is determined (see FIG. 9). The x and y coordinate values of each determined intersection (for example, the intersections J _{1 to} J _{6 in} FIG. 10) are extracted from the three-dimensional map data. The heights of these intersections are obtained by interpolation calculation using the height values of the vertices of the triangular mesh in a circle (search range) 141 having a radius r centered on the intersection.

For example, in FIG. 15, when calculating the height of an intersection point p (for example, the intersection point J ₅₎ on the cross-sectional line 21, a search range 141 with a radius r is set around the point p, and this search range is determined from the triangular mesh. The vertex q within 141 is determined. From the z values of the vertices q (for example, four vertices O ₄ , O ₅ , O ₆ , and O _{7 in this case} ) of n triangular meshes within the search range 141, the z value of the intersection point p is expressed by the equation (3 )

As described above, after determining the x, y, and z coordinate values of each intersection (for example, the intersections J _{1 to} J _{6 in} FIG. 10), in step S23, the midpoint or the start point a on the cross-sectional line is set as a reference point ( 0,0), the distance from the reference point is calculated for each intersection. Then, the intersections are arranged in order from the smallest distance. Using the height of each of the arranged points, a line 102 indicating a change in the height of a tree or a building along the cross-sectional line 21 is generated. As shown in FIG. 11, the generated tree height line 102 is superimposed on the ground height line 101 output in step S18 and is output (step S23).

  In principle, when generating tree lines with the same accuracy, the larger the number of vertices per unit area of the triangular mesh (the denser), the smaller the size r of the search range. However, even when the number of vertices per unit area of the triangular mesh is relatively small (sparse), the number of vertices is increased by increasing the size r of the search range or reducing the interval d as described above. It is possible to generate a tree line with the same accuracy as in the case of.

Claims (9)

A method for generating a cross section under a power transmission line for generating a cross section under the power transmission line from three-dimensional map data,
Displaying an xy plane map using the input 3D map data;
On the plane map display screen, generating a ground height line representing a change in ground height along a cross-sectional line indicated in a direction perpendicular to the span direction in which the transmission line is stretched;
Generating a tree line representing a change in the height of a tree on the ground along the cross-section line;
Including
The step of generating the tree line includes:
Setting the search range consisting of circles with a search radius centered on each point of interest, with the points separated by the specified interpolation interval in the longitudinal direction as the point of interest, and
From the triangular mesh data having three-dimensional coordinates (x, y, z) for the vertices of the triangles in the triangular mesh obtained by connecting the triangles set on the xy plane map to each other, they are within the search range. Determining a plurality of vertices;
The height values of the plurality of vertices are set to zq1, zq2,. + Wn = 1), and determining the height direction value zp at the point of interest by interpolation calculation represented by zp = (w1 · zq1 + w2 · zq2 + ... + wn · zqn);
Generating the tree line using the determined height of each point of interest;
A method for generating a lower cross-sectional view of a transmission line including A method for generating a cross section under a power transmission line for generating a cross section under the power transmission line from three-dimensional map data,
Displaying an xy plane map using the input 3D map data;
On the plane map display screen, generating a ground height line representing a change in ground height along a cross-sectional line indicated in a direction perpendicular to the span direction in which the transmission line is stretched;
Generating a tree line representing a change in the height of a tree on the ground along the cross-section line;
Including
The step of generating the tree line includes:
From the triangular mesh data having three-dimensional coordinates (x, y, z) for the vertices of the respective triangles in the triangular mesh in which the triangles set on the xy plane map are connected to each other, the section line and the triangle Determining a plurality of intersections where the mesh intersects;
The difference in height at the vertices at both ends of the triangle side on the triangular mesh where the intersection exists is the distance on the xy plane between the vertices at both ends, and one of the vertices at both ends and the intersection. Determining a height at the intersection by proportionally allocating according to a ratio with a distance on the xy plane;
Generating the tree line using the determined heights of the intersections;
A method for generating a lower cross-sectional view of a transmission line including The step of generating the ground height line includes:
Extracting, from the three-dimensional map data, x and y coordinates of a plurality of first intersections where the section line and contour line intersect, and x and y coordinates of a second intersection where the section line and feature intersect. ,
Determining a height at the first intersection point equal to the contour line;
The height at the second intersection point, the height difference between two first intersection points adjacent to the second intersection point, the distance on the xy plane between the two first intersection points, and the two Determining by proportionally allocating according to a ratio of a distance on one of the first intersections and the distance on the xy plane between the second intersections;
Using the determined height of the first intersection and the height of the plurality of second intersections to generate a ground height line representing a change in ground height along the cross-sectional line;
The transmission line lower cross-sectional view production | generation method of Claim 1 or 2 containing this. A transmission line lower cross section generation device for generating a cross section under a transmission line from three-dimensional map data,
Means for displaying an xy plane map using the input three-dimensional map data;
Means for generating a ground height line representing a change in ground height along a cross-sectional line indicated in a direction perpendicular to the span direction on which the transmission line is stretched on the display screen of the planar map;
Means for generating a tree line representing a change in the height of a tree on the ground along the cross-sectional line;
With
The means for generating the tree line is:
Set the search range consisting of circles with a search radius centered on each point of interest, with the points separated by the specified interpolation interval in the length direction as the cross-section line,
From the triangular mesh data having three-dimensional coordinates (x, y, z) for the vertices of the triangles in the triangular mesh obtained by connecting the triangles set on the xy plane map to each other, they are within the search range. Determine multiple vertices,
The height values of the plurality of vertices are set to zq1, zq2,. + Wn = 1), the value zp in the height direction at the point of interest is determined by interpolation calculation represented by zp = (w1 · zq1 + w2 · zq2 + ... + wn · zqn),
Using the determined height of each point of interest, the tree line is generated,
Transmission line bottom cross-sectional view generator. A transmission line lower cross section generation device that generates a cross section under a transmission line from three-dimensional map data,
Means for displaying an xy plane map using the input three-dimensional map data;
Means for generating a ground height line representing a change in ground height along a cross-sectional line indicated in a direction perpendicular to the span direction on which the transmission line is stretched on the display screen of the planar map;
Means for generating a tree line representing a change in the height of a tree on the ground along the cross-sectional line;
With
The means for generating the tree line is:
From the triangular mesh data having three-dimensional coordinates (x, y, z) for the vertices of the respective triangles in the triangular mesh in which the triangles set on the xy plane map are connected to each other, the section line and the triangle Determine multiple points of intersection with the mesh,
The difference in height at the vertices at both ends of the triangle side on the triangular mesh where the intersection exists is the distance on the xy plane between the vertices at both ends, and one of the vertices at both ends and the intersection. Determine the height at the intersection by proportionally allocating according to the ratio to the distance on the xy plane,
The tree line is generated using the determined heights of the plurality of intersection points.
Transmission line bottom cross-sectional view generator. The means for generating the ground height line is:
Extracting from the three-dimensional map data x, y coordinates of a plurality of first intersections where the section line and the contour line intersect, and x, y coordinates of a second intersection where the section line and the feature intersect,
Determining a height at the first intersection point equal to the contour line;
The height at the second intersection point, the height difference between two first intersection points adjacent to the second intersection point, the distance on the xy plane between the two first intersection points, and the two A proportional distribution according to a ratio of a distance on one of the first intersections and the distance on the xy plane between the second intersections;
The ground height line is generated using the determined height of the first intersection and the height of the plurality of second intersections.
The transmission line lower cross-sectional view production | generation apparatus of Claim 4 or 5. A computer-readable storage medium that stores a transmission line cross-sectional view generation program for generating a cross-section under a transmission line from three-dimensional map data,
The transmission line lower cross-sectional view generation program,
Displaying an xy plane map using the input 3D map data;
On the plane map display screen, generating a ground height line representing a change in ground height along a cross-sectional line indicated in a direction perpendicular to the span direction in which the transmission line is stretched;
Generating a tree line representing a change in the height of a tree on the ground along the cross-section line;
Including
The step of generating the tree line includes:
Setting the search range consisting of circles with a search radius centered on each point of interest, with the points separated by the specified interpolation interval in the longitudinal direction as the point of interest, and
From the triangular mesh data having three-dimensional coordinates (x, y, z) for the vertices of the triangles in the triangular mesh obtained by connecting the triangles set on the xy plane map to each other, they are within the search range. Determining a plurality of vertices;
The height values of the plurality of vertices are set to zq1, zq2,. + Wn = 1), and determining the height direction value zp at the point of interest by interpolation calculation represented by zp = (w1 · zq1 + w2 · zq2 + ... + wn · zqn);
Generating the tree line using the determined height of each point of interest;
A computer-readable storage medium including: A computer-readable storage medium storing a transmission line cross-sectional view generation program for generating a cross-section under a transmission line from three-dimensional map data,
The transmission line lower cross-sectional view generation program,
Displaying an xy plane map using the input 3D map data;
On the plane map display screen, generating a ground height line representing a change in ground height along a cross-sectional line indicated in a direction perpendicular to the span direction in which the transmission line is stretched;
Generating a tree line representing a change in the height of a tree on the ground along the cross-section line;
Including
The step of generating the tree line includes:
From the triangular mesh data having three-dimensional coordinates (x, y, z) for the vertices of the respective triangles in the triangular mesh in which the triangles set on the xy plane map are connected to each other, the section line and the triangle Determining a plurality of intersections where the mesh intersects;
The difference in height at the vertices at both ends of the triangle side on the triangular mesh where the intersection exists is the distance on the xy plane between the vertices at both ends, and one of the vertices at both ends and the intersection. Determining a height at the intersection by proportionally allocating according to a ratio with a distance on the xy plane;
Generating the tree line using the determined heights of the intersections;
A computer-readable storage medium. The step of generating the ground height line includes:
Extracting, from the three-dimensional map data, x and y coordinates of a plurality of first intersections where the section line and contour line intersect, and x and y coordinates of a second intersection where the section line and feature intersect. ,
Determining a height at the first intersection point equal to the contour line;
The height at the second intersection point, the height difference between two first intersection points adjacent to the second intersection point, the distance on the xy plane between the two first intersection points, and the two Determining by proportionally allocating according to a ratio of a distance on one of the first intersections and the distance on the xy plane between the second intersections;
Using the determined height of the first intersection and the height of the plurality of second intersections to generate a ground height line representing a change in ground height along the cross-sectional line;
A computer-readable storage medium according to claim 7 or 8, comprising:

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