Road edge heightening device

Abstract

To provide a road edge height provision device that can solve an existing problem by extracting the altitude of a road surface while avoiding a feature other than a road and providing a road edge height.SOLUTION: The road edge height provision device includes: three-dimensional feature model storage means; road edge model storage means; noted region setting means; and road edge height calculation means. The noted region setting means is means for generating a plurality of noted reference points on a road edge model and setting a noted region with reference to a noted reference point. The road edge height calculation means is means for extracting a plurality of structural points of the noted region as noted structural points when the noted region is arranged in a three-dimensional feature model and calculating the value of statistic of height information related to the noted structural points as a road edge height.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a technology for assigning height information such as elevation to features, and more specifically to a road edge height assigning device that determines the height of a road edge (hereinafter referred to as "road edge height") by performing statistical processing of height information near the road edge. [Background technology]

[0002] Recently, there has been an increasing demand for topographical information (spatial information). For example, an increasing number of managers are requesting spatial information on facilities, such as their shape and location, in order to more effectively manage facilities installed on or along roads. At the same time, advanced maintenance and management of social infrastructure (hereinafter simply referred to as "social infrastructure") is considered an important issue in realizing Society 5.0, which is currently being promoted jointly by the public and private sectors. Furthermore, as autonomous driving technology becomes more practical, there is a strong demand from many quarters for various spatial information related to roads, including road edges (road boundary lines).

[0003] Traditionally, two-dimensional (2D) planar drawings (floor plans), such as topographical maps, have been the mainstream for showing spatial information. Although plan views sometimes show "height information" such as contour lines and endpoint elevations, they are primarily focused on showing planar positions, making it difficult to grasp the target area as a three-dimensional (3D) space. However, in recent years, advances in measurement technology have made it easy to acquire large numbers of three-dimensional measurement points (hereinafter referred to as "3D point clouds"), and advances in information technology have also made it easier to handle these three-dimensional point clouds.

[0004] For example, to obtain a 3D point cloud of terrain including roads, measurement methods such as aerial photogrammetry, airborne laser measurement, terrestrial laser measurement, and MMS (Mobile Mapping System) are used. Among these, MMS is a system in which sensors such as a laser scanner, camera, a satellite positioning system (GNSS: Global Navigation Satellite System) for obtaining self-position, an IMU (Inertial Measurement Unit), and odometry are mounted on a moving vehicle, allowing the laser scanner to obtain a 3D point cloud while moving on the roadway.

[0005] The 3D point cloud obtained by MMS or other methods is generally used as a 3D model of the terrain to be measured (hereinafter referred to as a "3D terrain model"). This 3D terrain model represents the target terrain using 3D coordinates, and is a terrain model typified by DSM (Digital Surface Model) and DEM (Digital Elevation Model).

[0006] Typically, a 3D terrain model is composed of multiple small regions obtained by dividing the target planar area. These small regions, also known as meshes, are formed by dividing the area into, for example, orthogonal grids, and each small region has a representative point. Because the 3D point clouds obtained by measurement are often random data (data that is irregularly arranged on a plane), geometric calculations are often used to assign heights to the representative points of the small regions. Calculation methods include the Triangulated Irregular Network (TIN) method, which calculates height using an irregular triangulation network formed from random data, the Nearest Neighbor method, which uses the nearest laser measurement point, as well as inverse distance weighting (IDW), the Kriging method, and the averaging method.

[0007] 3D terrain models allow users to grasp the target terrain in both two-dimensional and three-dimensional terms, making them more versatile than flat maps. However, 3D terrain models based on measurement results only provide spatial information based on three-dimensional coordinates, and are unable to show the attributes of features. In other words, simply by looking at a 3D terrain model, users cannot tell where the edges of roads are or where the outer edges of office buildings (the so-called edges) are.

[0008] Adding feature attribute information to a 3D terrain model requires a survey of the features. This means extracting feature attributes by visually inspecting aerial photographs, or having workers go directly to the site and record the visual information on a map, which requires human judgment. However, because roads, for example, generally have considerable lengths, the amount of work required for the survey is enormous, and considering the labor and time involved, it requires significant costs.

[0009] As mentioned above, traditionally, flat maps have been the primary method of data collection. In some cases, these maps are used as raster or vector data (i.e., digitized), and in other cases, features are converted into shapes (polylines or polygons) and then assigned attribute information. Furthermore, recent advances in machine learning technology have made it possible to automatically extract features from aerial photographs and flat maps, and then extract their shapes and attribute information. In this way, it is conceivable that a separate "2D terrain model" is available that does not include elevation or other height information but does include feature attribute information. Using such a 2D terrain model can eliminate (or significantly reduce) the need for manual surveys of features when assigning feature attribute information to a 3D terrain model.

[0010] Therefore, Patent Document 1 proposes a technique for generating three-dimensional feature shape lines by adding elevations to the feature shape lines represented in two-dimensional map data using a point cloud obtained by measurement. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Japanese Patent Publication No. 2020-013351 Summary of the Invention [Problem to be solved by the invention]

[0012] As mentioned above, 3D terrain models only provide spatial information based on three-dimensional coordinates, and it is not possible to understand where the road edge is simply by looking at the 3D terrain model. Therefore, in order to assign road edge height, manual work, such as visually processing aerial photographs, is unavoidable, resulting in significant costs. Therefore, we suggested the possibility of reducing manual work by using "2D terrain models" that digitize plan views such as raster data and vector data.

[0013] For example, a two-dimensional terrain model (hereinafter referred to as a "road edge model") having attribute information of "road edge" and its planar position (coordinate information) can be placed on a 3D terrain model, and then constituent points around the road edge model can be extracted from the three-dimensional points (hereinafter referred to as "constituent points") that make up the 3D terrain model, and these can be used as the road edge height. However, buildings other than roads, such as houses and office buildings, are often located around road edges, and there are cases where a constituent point cannot immediately be used as the road edge height simply because it is located around the road edge model.

[0014] The object of the present invention is to solve the problems associated with the prior art, that is, to provide a road edge height assigning device that can assign a road edge height after extracting height information of the road surface. [Means for solving the problem]

[0015] The present invention focuses on the fact that a focus area and a focus line segment are generated based on a road edge model, and that the height information obtained by performing statistical processing on the focus area (focus line segment) is assigned as the road edge height, and is an invention based on an idea that has not been seen before.

[0016] The road edge height assignment device of the present invention comprises a 3D topographical model storage means, a road edge model storage means, a region of interest setting means, and a road edge height calculation means. The 3D topographical model storage means stores a 3D topographical model based on a plurality of constituent points having 3D coordinates, and the road edge model storage means stores a 2D road edge model representing a road edge. The region of interest setting means generates a plurality of reference points of interest on the road edge model and sets a 2D region of interest having a predetermined size and shape based on the reference points of interest. The road edge height calculation means extracts a plurality of constituent points belonging to the region of interest when the region of interest is placed on the 3D topographical model and calculates statistical values ​​of height information related to the reference points of interest as the road edge height. The road edge height is then assigned to the reference points of interest corresponding to the region of interest.

[0017] The road edge height assignment device of the present invention may further comprise a region of interest dividing means and a road side region setting means. The region of interest dividing means divides the region of interest into a plurality of divided regions using the road edge model as a boundary, and the road side region setting means calculates statistical values ​​of height information for a plurality of component points belonging to each divided region as a divided region representative height, and sets the divided region with the lowest divided region representative height as the road side region. In this case, the road edge height calculation means extracts a plurality of component points belonging to the road side region as target component points and then calculates the road edge height.

[0018] The road edge height assignment device of the present invention extracts two or more candidate divided areas that are adjacent to a target reference point from among the divided areas, and sets the candidate divided area with the lowest divided area representative height among the candidate divided areas as the road side area, and then calculates the road edge height.

[0019] The road edge height determination device of the present invention can also calculate the road edge height after setting a road side area using the median value of height information related to multiple component points belonging to a divided area as the divided area representative height.

[0020] The road edge height assignment device of the present invention may also be provided with a line segment of interest setting means instead of the area of ​​interest setting means. This line segment of interest setting means generates a plurality of reference points of interest on the road edge model and sets a two-dimensional line segment of interest having a predetermined length that is perpendicular to the road edge model and based on the reference points of interest. In this case, the road edge height calculation means extracts a plurality of component points near (including on) the line segment of interest when the line segment of interest is placed on the three-dimensional topographical model, and calculates the statistical value of the height information related to the component points of interest as the road edge height.

[0021] The road edge height assignment device of the present invention can also be configured to include a target line segment dividing means and a road side line segment setting means. The target line segment dividing means divides the target line segment into a plurality of dividing line segments using the road edge model as a boundary, and the road side line segment setting means calculates a statistical value of height information related to a plurality of component points in the vicinity of the dividing line segment (including on the line) as a dividing line segment representative height, and sets the dividing line segment with the lowest dividing line segment representative height as the road side line segment. In this case, the road edge height calculation means extracts a plurality of component points in the vicinity of the road side line segment (including on the line) as target component points and then calculates the road edge height.

[0022] The road edge height assignment device of the present invention extracts two or more candidate dividing line segments from among the dividing line segments, each having a target reference point as its end point, and sets the candidate dividing line segment with the lowest dividing line segment representative height among the candidate dividing line segments as the road side line segment, and then calculates the road edge height.

[0023] The road edge height assignment device of the present invention can also calculate the road edge height after setting a road side area using the median value of the height information for component points located near (including on) the dividing line segment as the dividing line segment representative height.

[0024] The road edge height determining device of the present invention can also calculate a predetermined percentile value of the height information related to the target constituent point as the road edge height. [Effects of the Invention]

[0025] The road edge height providing device of the present invention has the following effects. (1) Because the road edge model is used, road edge height can be automatically assigned. As a result, the burden on the operator (worker) can be reduced, the cost of data creation can be reduced, and so-called human error can be reduced. (2) It is possible to avoid incorrectly extracting the height of roofs around the road edge, and therefore to assign road edge heights that are appropriate to the current situation. (3) Road edges that are appropriate to the current situation are provided, meaning that a 3D terrain model that is appropriate to the current situation is obtained, which allows for more advanced management of road facilities, etc. and provides map information that is more useful for automated driving. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a block diagram showing the main configuration of a road edge height adjusting device according to a first embodiment of the present invention; [Figure 2] (a) is a planar model diagram that schematically shows the focus reference points generated at regular intervals on the road edge model by the focus area setting means, and (b) is a planar model diagram that schematically shows the focus area set as a circle centered on the focus reference point. [Figure 3] FIG. 3 is a planar model diagram that schematically shows a first divided area and a second divided area that are set by dividing the area of ​​interest by the area of ​​interest dividing means. [Figure 4]FIG. 3 is a planar model diagram showing a first divided region, a second divided region, a third divided region, and a fourth divided region set by the region-of-interest dividing means. [Figure 5] FIG. 3 is a flowchart showing an example of a main process flow of the road edge height setting device according to the first embodiment. [Figure 6] FIG. 4 is a block diagram showing the main configuration of a road edge height adjusting device according to a second embodiment of the present invention. [Figure 7] FIG. 10 is a planar model diagram schematically showing a line segment of interest set with a reference point of interest as a reference. [Figure 8] FIG. 4 is a planar model diagram that schematically shows a first divided line segment and a second divided line segment that are generated by dividing the target line segment by the target line segment dividing means. [Figure 9] FIG. 4 is a planar model diagram schematically showing a first dividing line segment, a second dividing line segment, a third dividing line segment, and a fourth dividing line segment set by a target line segment dividing means. [Figure 10] FIG. 10 is a flowchart showing an example of a main process flow of a road edge height setting device according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0027] An example of the road edge height providing device of the present invention will be described with reference to the drawings.

[0028] One of the technical features of the road edge height estimation device of the present invention is that it sets a plurality of reference points (hereinafter referred to as "target reference points") on the road edge at appropriate intervals and sets a predetermined range based on the target reference points. The setting of this "predetermined range" can be broadly divided into an embodiment (hereinafter referred to as "first embodiment") in which it is set by an area based on the target reference points (hereinafter referred to as "target area"), and an embodiment (hereinafter referred to as "second embodiment") in which it is set by a line segment based on the target reference points (hereinafter referred to as "target line segment"). Therefore, the first and second embodiments will be described separately.

[0029] 1. First embodiment 1 is a block diagram showing the main components of a road edge height determination device 100 according to the first embodiment of the present invention. As shown in this figure, the road edge height determination device 100 comprises a region of interest setting means 101, a road edge height calculation means 102, a 3D topographical model storage means 108, and a road edge model storage means 109, and may further comprise a region of interest division means 103 and a road side region setting means 104.

[0030] The target area setting means 101, road edge height calculation means 102, target area division means 103, and road side area setting means 104 that make up the road edge height assignment device 100 can be manufactured as dedicated units, or a general-purpose computer device can be used. This computer device has a processor such as a CPU, memories such as ROM and RAM, and some also include input means such as a mouse and keyboard, and a display, and can be configured, for example, as a personal computer (PC) or server.

[0031] The 3D terrain model storage means 108 and the road edge model storage means 109 can be implemented as a storage device of a general-purpose computer (for example, a personal computer), or can be implemented as a database server. When implemented as a database server, they can be placed on a local network (LAN: Local Area Network), or can be implemented as a cloud server that stores data via the Internet (i.e., wireless communication).

[0032] Hereinafter, each of the main elements constituting the road edge height adjusting device 100 of the present invention in the first embodiment will be described in detail.

[0033] (3D terrain model storage means) The three-dimensional terrain model storage means 108 is a means for storing a "3D terrain model." As mentioned above, a "3D terrain model" is a model composed of a large number of constituent points having three-dimensional coordinates (i.e., a three-dimensional point cloud), and examples thereof include a DSM and a DEM, but also includes a simple three-dimensional point cloud that is randomly arranged.

[0034] (Road edge model storage means) The road edge model storage means 109 is a means for storing a "road edge model." Here, the "road edge model" is, as described above, two-dimensional data that includes attribute information of the "road edge" and its planar position (coordinate information), and is digitized road edge data such as polylines.

[0035] (region of interest setting means) The area-of-interest setting means 101 is a means for generating a plurality of reference points of interest on a road edge model. The area-of-interest setting means 101 can automatically generate reference points of interest PA at regular intervals (or irregular intervals) on the road edge model EL as shown in Figure 2(a), or can set reference points of interest at arbitrary positions by an operator's operation. Furthermore, the positions of reference points of interest that have been generated can also be changed by an operator's operation.

[0036] The region-of-interest setting means 101 also sets a two-dimensional predetermined region (hereinafter referred to as "region of interest"). This region of interest is a region based on a reference point of interest PA, and is a two-dimensional region (planar region) having a predetermined size and shape. For example, as shown in FIG. 2(b), the region of interest RA can be a circle of a predetermined radius centered on the reference point of interest PA, or it can be an ellipse or polygon of predetermined dimensions centered on the reference point of interest PA.

[0037] (region of interest division means) The region of interest dividing means 103 is means for dividing the region of interest RA using the road edge model EL as a boundary, thereby setting a plurality of regions (hereinafter referred to as "divided regions RS"). For example, in FIG. 3, the region of interest dividing means 103 divides the circular region of interest RA in half to set a first divided region RS01 and a second divided region RS02. Note that the region of interest RA shown in FIG. 3 is a circle centered on the reference point of interest PA, and the road edge model EL naturally passes through the reference point of interest PA, so the first divided region RS01 and the second divided region RS02 are each semicircular (with a central angle of 180°) with the same shape and area. Of course, if the road edge model EL is bent, the semicircular regions will not have the same area, and fan-shaped divided regions with different areas will be set. If the road edge model EL is bent at multiple points within the region of interest RA, the region will not be fan-shaped. Furthermore, if the region of interest RA is not circular, it will not be fan-shaped either. In either case, the region of interest RA is divided by the road edge model EL.

[0038] (Road side area setting means) As shown in Figure 3, when an area of ​​interest RA is placed on a 3D terrain model, several composition points PC belong to that area of ​​interest RA. Since the composition points PC have height information (for convenience, the following description will be given using an example in which "height information" is referred to as "elevation value"), the elevation value of the reference point of interest PA related to the area of ​​interest RA can be obtained by using the composition points PC belonging to the area of ​​interest RA. Note that "belonging to the area of ​​interest RA" here means that when the composition points PC are projected onto the area of ​​interest RA, the composition points PC are included within the area of ​​the area of ​​interest RA.

[0039] In many cases, one side of the road edge is a road, and the other side is a non-road area (hereinafter referred to as a "general area"). Therefore, when the area of ​​interest RA is divided into two divided areas RS (a first divided area RS01 and a second divided area RS02) as shown in Figure 3, it is desirable to select one of them as a road, and then determine the elevation value of the reference point of interest PA based on the component point PC that belongs to the divided area RS that is determined to be a road (hereinafter referred to as a "road side area").

[0040] The road-side area setting means 104 is a means for setting a road-side area from among the plurality of divided areas RS. The processing procedure by the road-side area setting means 104 for setting a road-side area will be described in detail below. First, the road-side area setting means 104 calculates an elevation value (hereinafter referred to as a "divided area representative height") that represents the divided area RS based on elevation values ​​for the plurality of component points PC belonging to that divided area RS. At this time, the divided area representative height can be the median value of the elevation values ​​for the plurality of component points PC, or another statistical value such as the average value, mode, or low elevation value percentile (described later) of the elevation values ​​for the component points PC, or can simply be the minimum value of the elevation values ​​for the component points PC.

[0041] Once the divided area representative height for each divided area RS is obtained, the road-side area setting means 104 selects one divided area RS from those divided areas RS. Generally, roads have lower elevation values ​​than general areas. Therefore, the road-side area setting means 104 extracts the divided area representative height showing the smallest (lowest) value, selects the divided area RS corresponding to the extracted divided area representative height, and sets it as the road-side area.

[0042] 3, two divided areas RS (first divided area RS01 and second divided area RS02) are set by the area-of-interest dividing means 103, but the area-of-interest dividing means 103 may set three or more divided areas RS. For example, FIG. 4 shows a so-called T-junction intersection, and the area of ​​interest RA is set by a circle with a relatively large radius. In this case, the area-of-interest dividing means 103 divides the area of ​​interest RA by three road edge models EL, thereby setting four divided areas RS (first divided area RS01, second divided area RS02, third divided area RS03, and fourth divided area RS04).

[0043] When three or more divided areas RS are set, the road-side area setting means 104 calculates the divided area representative height for each divided area RS, extracts the divided area representative height showing the smallest (lowest) value, and sets the divided area RS related to the extracted divided area representative height as the road-side area. Alternatively, the road-side area setting means 104 can extract a divided area RS that contacts the target reference point PA from the three or more divided areas RS (hereinafter referred to as a "candidate divided area") and set the road-side area. As can be seen from FIG. 4, it is clear that the divided area RS that contacts the target reference point PA is the road-side area. Therefore, when three or more divided areas RS are set, the divided area RS that contacts the target reference point PA is extracted as a "candidate divided area," and a road-side area is set by selecting from these candidate divided areas. In the example of Figure 4, four divided areas RS (first divided area RS01 to fourth divided area RS04) have been set, so the road side area setting means 104 extracts the first divided area RS01 and the second divided area RS02, which are adjacent to the target reference point PA, as candidate divided areas, and calculates the divided area representative heights for these candidate divided areas (i.e., the first divided area RS01 and the second divided area RS02), extracts the divided area representative height that shows the smallest elevation value, and then sets the road side area (the second divided area RS02 in Figure 4).

[0044] (Road edge height calculation method) The road edge height calculation means 102 is a means for calculating the "road edge height" based on the road side area set by the road side area setting means 104. The processing procedure by which the road edge height calculation means 102 calculates the road edge height will be described in detail below. First, the road edge height calculation means 102 extracts a component point PC (hereinafter, particularly referred to as a "target component point") that belongs to the road side area. Then, the road edge height is calculated using the elevation value of the extracted target component point. At this time, when one target component point is extracted by the road edge height calculation means 102, the elevation value associated with that target component point is used as the road edge height. On the other hand, when two or more target component points are extracted, the elevation value that is a specific lower elevation percentile among the elevation values ​​associated with the two or more target component points is used as the road edge height. Here, the lower elevation percentile refers to the conventionally used concept of percentile, and is a concept that particularly refers to a sample located at a specific percentile counting from the lowest. For example, when arranging from lowest to highest using an elevation value of 200, the 10th noted component point counting from the side with the smallest elevation value will be the 5th percentile, and if the lower elevation percentile is specified as the 3rd percentile, the 6th noted component point will be selected. In addition, a value obtained by statistically processing the elevation values ​​of two or more noted component points (such as the median or mode) can be used as the road edge height, or simply the minimum value of the elevation values ​​of the noted component points can be used as the road edge height. The road edge height obtained here is assigned to the noted reference point PA for the corresponding noted area RA as the road edge height.

[0045] So far, we have explained the processing procedure in which the road edge height calculation means 102 calculates the road edge height based on the road side areas selected from the multiple divided areas RS. However, the road edge height calculation means 102 can also be configured to set all of the component points PC belonging to the area of ​​interest RA as the component points of interest and calculate statistical values ​​(low-altitude percentile, median, mode) based on these component points of interest as the road edge height. In other words, in this case, the process of dividing the area of ​​interest RA to set the divided areas RS or the process of setting the road side areas is not executed, and the road edge height is simply calculated using the component points of interest related to the area of ​​interest RA. Therefore, in this case, the area of ​​interest division means 103 and the road side area setting means 104 can be omitted.

[0046] (Processing flow) The main processing of the road edge height setting device 100 in the first embodiment will be described in detail below with reference to Figure 5. Figure 5 is a flow diagram showing an example of the flow of the main processing of the road edge height setting device 100 in the first embodiment. In this flow diagram, the action to be performed is shown in the center column, the things necessary for that action are shown in the left column, and the things resulting from that action are shown in the right column.

[0047] As shown in Fig. 5, first, the road edge model EL is read from the road edge model storage means 109 (Fig. 1), and the region of interest setting means 101 generates a plurality of reference points of interest on the road edge model EL (Step 211 in Fig. 5). Furthermore, the region of interest setting means 101 sets a region of interest RA based on the reference points of interest PA (Step 212 in Fig. 5).

[0048] Once the area of ​​interest RA is set, the area of ​​interest dividing means 103 sets a plurality of divided areas RS (Step 213 in FIG. 5). Then, the road side area setting means 104 calculates a divided area representative height for each divided area RS (Step 214 in FIG. 5), and sets the road side areas based on the divided area representative height (Step 215 in FIG. 5).

[0049] Once the road side area is set, the road edge height calculation means 102 extracts the component points PC belonging to this road side area as target component points (Step 216 in FIG. 5), and calculates the road edge height based on these target component points (Step 217 in FIG. 5). The road edge height obtained here is then assigned as the road edge height of the target reference point PA for the corresponding target area RA. Note that the series of processes from setting the target area RA (Step 212) to calculating the road edge height (Step 217) can be performed for all target reference points PA, or can be performed for a specific section (e.g., intersection to intersection) as a unit. In this case, this series of processes (Steps 212 to 217) can be performed only for one target reference point PA that represents the specific section to set the road side area (e.g., the left side of the road edge model EL), and this road side area side (e.g., the left side) can be applied to other target reference points PA within the specific section. Alternatively, the process can be performed on all or some of the target reference points PA within a specific section to set the road side area, and the side with the larger number (e.g., the left side) can be set as the road side area side (e.g., the left side) within the specific section.

[0050] 2. Second embodiment Next, a second embodiment of the present invention will be described. Note that although the first and second embodiments of the present invention differ in the method of setting the region of interest RA, they are generally common in other respects. Therefore, we will avoid any overlapping description with the first embodiment of the present invention explained so far, and will only explain the content unique to the second embodiment of the present invention. In other words, the content not described here is the same as that explained in "1. First Embodiment."

[0051] 6 is a block diagram showing the main components of the road edge height setting device 100 of the present invention in the second embodiment. As shown in this figure, the road edge height setting device 100 comprises a target line segment setting means 105, a road edge height calculation means 102, a 3D topographical model storage means 108, and a road edge model storage means 109, and can also comprise a target line segment division means 106 and a road side line segment setting means 107.

[0052] The target line segment setting means 105, road edge height calculation means 102, target line segment division means 106, and road side line segment setting means 107 that make up the road edge height assignment device 100 can be manufactured as dedicated units, or a general-purpose computer device can be used. This computer device has a processor such as a CPU, memories such as ROM and RAM, and some also include input means such as a mouse and keyboard, and a display, and can be configured, for example, as a personal computer (PC) or server.

[0053] Hereinafter, each of the main elements constituting the road edge height adjusting device 100 of the present invention in the second embodiment will be described in detail.

[0054] (Means for setting a line segment of interest) The target line segment setting means 105 is a means for generating a plurality of target reference points on the road edge model and setting a line segment (hereinafter referred to as "target line segment") that uses the target reference point PA as a reference. As shown in Figure 7, the target line segment SA is a line segment that is perpendicular to the road edge model EL and passes through the target reference point PA, and is set with a predetermined length. The target line segment is set on the same plane as the road edge model EL.

[0055] (Method for dividing lines of interest) The target line segment dividing means 106 is means for dividing the target line segment SA using the road edge model EL as a boundary to set a plurality of line segments (hereinafter referred to as "dividing line segments SS"). For example, in FIG. 8, the target line segment dividing means 105 divides the target line segment SA in half to set a first dividing line segment SS01 and a second dividing line segment SS02. Note that the midpoint of the target line segment SA shown in FIG. 8 coincides with the target reference point PA, so the first dividing line segment SS01 and the second dividing line segment SS02 are set to have the same dimension (length).

[0056] (Road side line segment setting means) As shown in Figure 8, when a line segment SA of interest is placed on a 3D terrain model, several component points PC will be placed on or near the line segment SA of interest. Here, "near the line segment SA of interest" literally means that the point is close to the line segment SA of interest, and more specifically, it means that the point is closer to the line segment SA of interest than a predetermined distance threshold; for example, if the length of a perpendicular line set from the point PC to the line segment SA of interest is less than this distance threshold, the point PC is considered to be near the line segment SA of interest.

[0057] As mentioned above, one side of the road edge is the road and the other side is the general area. Therefore, when the target line segment SA is divided into two dividing line segments SS (the first dividing line segment SS01 and the second dividing line segment SS02) as shown in Figure 8, it is desirable to select one of them as the road and then determine the elevation value of the target reference point PA based on the constituent point PC on or near the dividing line segment SS (hereinafter referred to specifically as the "road side line segment") that has been selected as the road.

[0058] The road side line segment setting means 107 is a means for setting a road side line segment from among the plurality of dividing line segments SS. The processing procedure for setting a road side line segment by the road side line segment setting means 107 will be described in detail below. First, the road side line segment setting means 107 calculates an elevation value (hereinafter referred to as a "dividing line segment representative height") that represents the dividing line segment SS based on the elevation values ​​of the plurality of component points PC that are on or near the dividing line segment SS. At this time, the dividing line segment representative height can be the median value of the elevation values ​​of the plurality of component points PC, or another statistical value such as the average value, mode, or low elevation value percentile of the elevation values ​​of the component points PC, or can simply be the minimum value of the elevation values ​​of the component points PC.

[0059] Once the dividing line segment representative heights for each dividing line segment SS are obtained, the road side line segment setting means 107 selects one dividing line segment SS from those dividing line segments SS. Generally, roads have lower elevation values ​​than general areas. Therefore, the road side line segment setting means 107 extracts the dividing line segment representative height that shows the smallest (lowest) value, selects the dividing line segment SS related to the extracted dividing line segment representative height, and sets it as a road side line segment.

[0060] In the example of Figure 8, two dividing line segments SS (first dividing line segment SS01 and second dividing line segment SS02) are set by the target line segment dividing means 106, but the target line segment dividing means 106 may also set three or more dividing line segments SS. For example, Figure 9 shows a main road and a side road parallel to it, and the target line segment SA is set with a relatively long dimension. In this case, the target line segment dividing means 106 divides the target line segment SA with three road edge models EL (one of which is folded back in a U-shape), thereby setting five dividing line segments SS (first dividing line segment SS01, second dividing line segment SS02, third dividing line segment SS03, fourth dividing line segment SS04, and fifth dividing line segment SS05).

[0061] When three or more dividing line segments SS are set, the road-side line segment setting means 107 calculates a dividing line segment representative height for each dividing line segment SS, extracts the dividing line segment representative height with the smallest (lowest) value, and sets the dividing line segment SS associated with the extracted dividing line segment representative height as the road-side line segment. Alternatively, the road-side line segment setting means 107 can extract dividing line segments SS having a target reference point PA as an end point from the three or more dividing line segments SS (hereinafter referred to as "candidate dividing line segments") and set the road-side line segments. As can be seen from FIG. 9, it is clear that dividing line segments SS having a target reference point PA as an end point are road-side line segments. Therefore, when three or more dividing line segments SS are set, dividing line segments SS having a target reference point PA as an end point are extracted as "candidate dividing line segments," and road-side lines are set by selecting from these candidate dividing line segments. In the example of Figure 9, five dividing line segments SS (first dividing line segment SS01 to fifth dividing line segment SS05) have been set, so the road side line segment setting means 107 extracts the first dividing line segment SS01 and the second dividing line segment SS02, which have the target reference point PA as their endpoints, as candidate dividing line segments, calculates dividing line segment representative heights for these candidate dividing line segments (i.e., the first dividing line segment SS01 and the second dividing line segment SS02), extracts the dividing line segment representative height that shows the smallest value, and then sets the road side line segment (the second dividing line segment SS02 in Figure 9).

[0062] (Road edge height calculation means in the second embodiment) The road edge height calculation means 102 in the second embodiment calculates the "road edge height" based on the road side line segment set by the road side line segment setting means 107. The processing procedure for calculating the road edge height by the road edge height calculation means 102 in the second embodiment will be described in detail below. First, the road edge height calculation means 102 extracts a component point PC ("target component point" in the second embodiment) that is on or near the road side line segment. Then, the road edge height is calculated using the elevation value of the extracted target component point. At this time, when one target component point is extracted by the road edge height calculation means 102, the elevation value related to that target component point is used as the road edge height as is. On the other hand, when two or more target component points are extracted, the elevation value that is at a specific lower elevation percentile among the elevation values ​​related to the two or more target component points is used as the road edge height. Alternatively, the road edge height may be determined by statistically processing the elevation values ​​of two or more target points (such as the median or mode), or by simply using the minimum elevation value of the target points. The road edge height obtained in this way is assigned as the road edge height of the target reference point PA associated with the corresponding target line segment SA.

[0063] So far, we have explained the processing procedure in which the road edge height calculation means 102 calculates the road edge height based on a road side line segment selected from multiple dividing line segments SS. However, the road edge height calculation means 102 can also be configured to set all of the component points PC on or near the target line segment SA as target component points and calculate statistical values ​​(low-elevation percentile, median, mode) based on these target component points as the road edge height. In other words, in this case, the process of dividing the target line segment SA and setting a dividing line segment RS or the process of setting a road side line segment is not performed, and the target component points related to the target line segment SA are simply used to calculate the road edge height. Therefore, in this case, the target line segment dividing means 106 and the road side line segment setting means 107 can be omitted.

[0064] (Processing flow) The main processing of the road edge height setting device 100 in the second embodiment will be described in detail below with reference to Figure 10. Figure 10 is a flow diagram showing an example of the flow of the main processing of the road edge height setting device 100 in the second embodiment. In this flow diagram, the action to be performed is shown in the center column, the things necessary for that action are shown in the left column, and the things resulting from that action are shown in the right column.

[0065] As shown in Fig. 10, first, the road edge model EL is read from the road edge model storage means 109 (Fig. 6), and the target line segment setting means 105 generates a plurality of target reference points PA on the road edge model EL (Step 221 in Fig. 10). Furthermore, the target line segment setting means 105 sets a target line segment SA based on the target reference point PA (Step 222 in Fig. 10).

[0066] Once the target line segment SA is set, the target line segment dividing means 106 sets multiple dividing line segments SS (Step 223 in FIG. 10). Then, the road side line segment setting means 107 calculates a dividing line segment representative height for each dividing line segment SS (Step 224 in FIG. 10), and sets the road side line segments based on the dividing line segment representative heights (Step 225 in FIG. 10).

[0067] Once the road side line segment is set, the road edge height calculation means 102 extracts the component points PC on or near the road side line segment as target component points (Step 226 in FIG. 10), and calculates the road edge height based on these target component points (Step 227 in FIG. 10). The road edge height obtained here is then assigned as the road edge height of the target reference point PA for the corresponding target line segment SA. Note that the series of processes from setting the target line segment SA (Step 222) to calculating the road edge height (Step 227) can be performed for all target reference points PA, or can be performed for a specific section (e.g., intersection to intersection) as a unit. In this case, this series of processes (Steps 222 to 227) can be performed only for one target reference point PA that represents the specific section to set a road side line segment (e.g., to the left of the road edge model EL), and this road side line segment (e.g., to the left) can be applied to other target reference points PA within the specific section. Alternatively, the process can be performed on all or some of the target reference points PA within a specific section to set road side line segments, and the side with the greater number (e.g., the left side) can be set as the road side line segment (e.g., the left side) within the specific section. [Industrial Applicability]

[0068] The road curb height adjustment device of the present invention can be particularly suitably used for managing various facilities, including road facilities, and as map information used in automatic driving. Furthermore, according to the present invention, it is possible to provide highly accurate step information that is useful for elderly people and wheelchair users, and it can also be effectively used in disaster prevention plans. Therefore, the road curb height adjustment device of the present invention is not only applicable to industry, but is also expected to make a great contribution to society. [Explanation of symbols]

[0069] 100 Road edge height providing device of the present invention 101 (Road edge height setting device) focus area setting means 102 (Road edge height calculation means of road edge height assignment device) 103 (Road edge height assigning device) target area division means 104 (Road edge height setting device) road side area setting means 105 (Road edge height setting device) target line segment setting means 106 (Road edge height assigning device) target line segment division means 107 (Road edge height setting device) road side line segment setting means 108 (Road edge height setting device) 3D terrain model storage means 109 Road edge model storage means (of road edge height assigning device) EL Road Edge Model PA Reference Point PC configuration point RA Area of ​​Interest RS split area SA Focus line segment SS dividing line

Claims

1. a three-dimensional terrain model storage means for storing a three-dimensional terrain model based on a plurality of constituent points having three-dimensional coordinates; road edge model storage means for storing a two-dimensional road edge model representing a road edge; an area-of-interest setting means for generating a plurality of reference points of interest on the road edge model and setting a two-dimensional area of ​​interest having a predetermined size and shape based on the reference points of interest; a region-of-interest dividing means for dividing the region of interest into a plurality of divided regions using the road edge model as a boundary; a road-side area setting means for calculating, when the divided areas are arranged on the three-dimensional topographical model, statistical values ​​of height information relating to the plurality of component points belonging to the divided areas as divided-area representative heights, and setting the divided area relating to the lowest divided-area representative height as a road-side area; a road edge height calculation means for extracting a plurality of the constituent points belonging to the road side area as constituent points of interest, and calculating a statistical value of height information relating to the constituent points of interest as a road edge height, assigning the road edge height to the target reference point corresponding to the target area; A road edge height providing device.

2. the road-side area setting means extracts two or more candidate divided areas that contact the target reference point from among the divided areas, and sets the candidate divided area associated with the lowest divided area representative height as the road-side area.

2. The road edge height providing device according to claim 1.

3. The road side area setting means calculates a median value of height information relating to the plurality of component points belonging to the divided area as the divided area representative height, and then sets the road side area.

3. The road edge height providing device according to claim 1 or 2.

4. a three-dimensional terrain model storage means for storing a three-dimensional terrain model based on a plurality of constituent points having three-dimensional coordinates; road edge model storage means for storing a two-dimensional road edge model representing a road edge; a line segment of interest setting means for generating a plurality of reference points of interest on the road edge model and setting a two-dimensional line segment of interest having a predetermined length and perpendicular to the road edge model using the reference points of interest as references; a line segment of interest dividing means for dividing the line segment of interest into a plurality of divided line segments using the road edge model as a boundary; a road side line segment setting means for calculating a statistical value of height information relating to a plurality of component points on and / or in the vicinity of the dividing line segment when the dividing line segment is placed on the three-dimensional topographical model as a dividing line segment representative height, and for setting the dividing line segment relating to the lowest dividing line segment representative height as a road side line segment; a road edge height calculation means for extracting a plurality of the constituent points on and / or in the vicinity of the road side line segment as target constituent points, and calculating a statistical value of height information relating to the target constituent points as the road edge height, assigning the road edge height to the target reference point corresponding to the target line segment; A road edge height providing device.

5. the road-side line segment setting means extracts two or more candidate dividing line segments from the dividing line segments, each having an end point at the target reference point, and sets the candidate dividing line segment associated with the lowest dividing line segment representative height as the road-side line segment.

5. The road edge height providing device according to claim 4.

6. the road side line segment setting means calculates a median value of height information relating to the component points on and / or in the vicinity of the dividing line segment as the dividing line segment representative height, and then sets the road side line segment.

6. The road edge height providing device according to claim 4 or 5.

7. the road edge height calculation means calculates a predetermined percentile value of height information related to the target constituent point as the road edge height; 7. The road edge height providing device according to claim 1, wherein the road edge height providing device is a road edge height adjusting device.

Images