KR100350362B1 - Method and apparatus of making a 3-dimensional map - Google Patents

Abstract

3D model is produced from 2D map information by using rapid prototyping technology, and then realistic 3D map is projected by projecting the image taken by aircraft or computer graphic processed image or image of existing 2D map on 3D model. It provides a method and apparatus for manufacturing. By using these methods and devices, three-dimensional maps can be produced, so that the terrain / features of the region of interest can be identified at a glance, and newly installed bridges, buildings, roads, etc. can be easily updated, and urban development, civil engineering, It can be applied to military operations.

Description

3D mapping method and apparatus {METHOD AND APPARATUS OF MAKING A 3-DIMENSIONAL MAP}

According to the present invention, a three-dimensional model is produced from two-dimensional map information, and then a realistic three-dimensional map is produced by projecting a photograph taken from an aircraft, a computer graphics processed image, or an image of an existing two-dimensional map on the three-dimensional model. A method and apparatus are provided.

So far, the map has displayed the elevation of the terrain by using the contour line on the paper (two-dimensional). However, in general, since the contours alone cannot easily understand the complex terrain, the 3D map is urgently needed for important civil works. In some cases, the 3D model has already been produced and used as a bird's eye view, but since the roads, mountains, rivers, and villages are directly painted with paint, the terrain may not be accurate, and newly constructed or developed bridges and roads However, the disadvantage is that the terrain cannot be updated every time. That is, this requires a lot of time and budget, has a disadvantage that it is difficult to give a variety of colors and textures according to the terrain and compare them.

Accordingly, it is an object of the present invention to provide a method and apparatus for providing a sense of reality using real images so that various colors and textures of the terrain can be easily reviewed so that they can be seen in accordance with the actual terrain.

In order to achieve the above object, the three-dimensional map production apparatus according to the present invention is a shape extraction unit for extracting the three-dimensional shape information from the two-dimensional map information, and STL (stereolithography) that can recognize the three-dimensional shape information Projecting a data converter for converting data into data, a rapid molding machine for producing a three-dimensional model based on STL data, a support for supporting the three-dimensional model, and a two-dimensional image corresponding to two-dimensional map information on the three-dimensional model And an image corrector for correcting a mismatch between the projected 2D image and the 3D model.

In addition, another object of the present invention is to provide a technique for converting two-dimensional map information into three-dimensional STL (stereolithography) data that can be recognized by a rapid molding machine.

Another object of the present invention is to provide a method of correcting a mismatched image when a 2D image is projected onto a 3D model by using the shape, position, and orientation information of the 3D map and the focal length of the projector. It is.

1 is a view showing a three-dimensional mapping device.

FIG. 2 is a diagram specifically showing an example of triangular information for converting extracted three-dimensional shape information into STL data; FIG.

3 is a view showing a projector for projecting a terrain image or a two-dimensional map image to a three-dimensional model in the present invention.

4 is a diagram illustrating a case where a boundary line of a topographical image and a boundary line of a three-dimensional model are inconsistent (a) and a case where they coincide (b).

5 shows the principle of a correction method using the perspective projection technique of the present invention.

6 is a view showing a three-dimensional model of Dobongsan manufactured in a rapid molding machine in an embodiment of the present invention.

FIG. 7 illustrates a two-dimensional image of Dobongsan Mountain to be projected onto the three-dimensional model of FIG. 6 according to an embodiment of the present invention. FIG.

8 illustrates a three-dimensional map in accordance with an embodiment of the present invention.

Hereinafter, with reference to the drawings will be described the configuration and embodiment of the present invention.

1 shows a configuration diagram of a three-dimensional map making apparatus 1 according to the present invention. First, in order to produce a three-dimensional map, the shape extraction unit 3 extracts three-dimensional shape information from the two-dimensional map information. The data converter 4 converts the three-dimensional shape information extracted by the shape extractor 3 into STL (stereolithography) data that can be recognized by the rapid molding machine 5, and the rapid molding machine 5 is a data converter. Recognizing the STL data from (4), the three-dimensional model 7 is produced on the support 6 using a lamination method. In order to produce a realistic three-dimensional map, the projector 8 projects two-dimensional images such as topographical images, two-dimensional map images, computer graphics processed images, and the like on the manufactured three-dimensional model 7. If the projected two-dimensional image and the produced three-dimensional model 7 do not match, the image correction unit 9 adjusts the focal length of the projector 8 and the distance between the three-dimensional model 7 and the projector 8. Three-dimensional graphics perspective techniques are used to correct for discrepancies between the two-dimensional image and the three-dimensional model (7).

In more detail, in order to produce a 3D model from the 2D map information, Rapid Prototyping technology should be used. In order to use such rapid prototyping technology, it is necessary to convert 2D map information into 3D STL data that can be recognized by the rapid prototyping machine. 2 specifically illustrates a method of defining triangle information that is a component of STL data. The STL data format is a standard input data method of a rapid molding machine, and is a method of defining a three-dimensional shape by representing a surface surrounding an object in a fine triangular network. Each triangular information consists of coordinates of three vertices and a normal vector.

First, in order to convert 2D map information into 3D STL data, 3D shape information is extracted from 2D map information of the terrain to be produced. Extracting three-dimensional shape information from the two-dimensional map information of the terrain internally assigns a serial number of contour lines from the sea level, manages contours of the same number separately, extracts curves forming contour lines, and stores them separately.

Then, the extracted three-dimensional shape information is converted into STL data. Curve modeling is used to convert the contours of the map into closed boundary curves, respectively. Then, as shown in Fig. 2, STL data is obtained by generating appropriate points in consideration of the required precision in the closed curve, and generating points and triangular elements in the adjacent closed curve.

The rapid molding machine receives STL data and creates a three-dimensional model that fits the final terrain using the stacking method. In this way, a 3D model is produced from the 2D map information by using a rapid molding machine.

The 3D model produced by the rapid molding machine can visually check the height and height of the shape, but lacks the realism because the main features are not displayed. Therefore, in order to achieve the same effect that a 3D map actually sees from an aircraft, an aerial photograph, a satellite photograph, or a computer graphic image of a mountain, road, village, sea, river, etc. It is necessary to greatly increase the realism of the terrain by projecting the map image vertically on the 3D model. Therefore, for this purpose, a photograph taken from an aircraft, a satellite, an image of a two-dimensional map, or a computer graphics processed image is produced and projected onto a three-dimensional model using a projector.

FIG. 3 illustrates an apparatus for projecting a topographical image taken from an aircraft, a satellite, or an image of a two-dimensional map or a computer graphic image on a manufactured three-dimensional model. The projector may use a general beam projector, but may be specially manufactured according to the installation method of the projection system. However, the configuration is composed of lamps, LCD panels, prisms, lenses, etc., like commercially available beam projectors, and computer-generated images (air photographs, two-dimensional map images, computer graphics, etc.) are applied to the LCD panel in the projector. It displays and projects the object. Also, the projector moves the projection lens to a desired position / direction in consideration of the position / orientation of the map from the support of the three-dimensional model.

As such, when the terrain image taken from the aircraft is placed on the projector, the image is projected onto the three-dimensional model to provide a three-dimensional map showing a much more realistic terrain. In addition, the flow of waterfalls and rivers can be projected directly onto the map to give the effect that water is actually flowing.

However, when the two-dimensional image is projected onto the three-dimensional model, an inconsistency in the image may occur if the marking point on the photographed photograph and the corresponding point on the three-dimensional model do not coincide exactly. Therefore, a correction is necessary to prevent this.

FIG. 4 shows the case where the image is projected onto the three-dimensional model, and the case where the image is inconsistent (FIG. 4A) (FIG. 4B). As described above, in order to show a realistic terrain, the boundary line of the image and the three-dimensional boundary line must match as shown in (b) of FIG. 4.

As described above, in order to accurately match the terrain image with the corresponding position on the 3D model, the present invention performs a calibration operation as follows. That is, assuming that the focal length of the projector is f and the distance between the three-dimensional model and the projector is L, f and L are corrected using a perspective projection technique of three-dimensional graphics. That is, the inconsistency of the image is corrected by using the shape, position and orientation information of the 3D model and the focal length of the projector.

This correction method will be described in detail with reference to FIG. 5. In FIG. 5A, a is the length of one side of the LCD panel, W is the length of one side of the 3D map, and L is the distance from the LCD panel to the 3D map. The focal length f of the projection system can be obtained from the relation of, W, and L. That is, since (f + L): f = W: a, the focal length f of the projection system is f = aL / (W-a). The image inconsistency caused when projecting the computer image through the projector was corrected by making the focal length value in the graphic configuration of the two-dimensional computer image projected onto the three-dimensional model equal to the calculated focal length f value of the projection system.

The corrected image is transmitted to the projector and projected onto the three-dimensional model, thereby completing a three-dimensional map in which the topography is given to the three-dimensional model.

As described above, according to the present invention, a three-dimensional map can be produced by projecting an image having color and texture according to the terrain onto a three-dimensional model using computer image technology.

In addition, the existing two-dimensional map can not update the changed terrain and features, for this purpose, the map must be re-created. However, when the 3D map is updated on the computer screen, the updated image is projected onto the 3D terrain through the projector, so that the change of the terrain and features can be reflected in real time. In other words, changing an image on a computer updates the entire three-dimensional map.

In addition, according to the present invention, if a river flows or a waterfall falls and is implemented using computer graphics technology, and then projected onto a three-dimensional model, the river may actually flow or the waterfall falls. In addition, it can have various effects such as changing seasons, moving armored units, sunrises and sunsets. By utilizing these various effects, the present invention can be utilized as a simulator by incorporating computer animation technology.

(Example)

In the present invention, the topography of Dobongsan Mountain was selected to show an example of producing a 3D map. FIG. 6 illustrates a three-dimensional model of Dobongsan Mountain, which was manufactured by using a rapid molding machine after obtaining STL data from two-dimensional map information. It can be seen from FIG. 6 that the three-dimensional model without color and texture is still lacking in realism.

In order to produce a three-dimensional map similar to the actual state of Dobongsan, the two-dimensional image of FIG. 7 was projected onto the Dobongsan model. The three-dimensional map of Dobongsan Mountain, which is an image projected, is as shown in FIG. Compared with FIG. 6, it is easy to grasp not only the terrain but also location information such as a hiking trail, a valley, a ridge and a temple.

The present invention has the advantages of simple device configuration and ease of use compared to existing technologies such as virtual reality. Three-dimensional maps made from the fabricated device make it easy to accurately understand the terrain and features, and can easily update the surrounding conditions due to weathering, civil works, and seasonal changes.

In addition, the device of the present invention has the effect that can be used for military operations because it can reflect the position of the infantry, armored forces in the surrounding terrain in real time.

Claims (8)

In the method of making a three-dimensional map, Extracting three-dimensional shape information from the two-dimensional map information; Converting the extracted three-dimensional shape information into stereolithography (STL) data; Manufacturing a 3D model using a rapid prototyping method based on the STL data; Projecting a 2D image corresponding to the 2D map information onto the produced 3D model; And Correcting a mismatch between the two-dimensional image and the manufactured three-dimensional model based on the projection result. Method of producing a three-dimensional map comprising a. The method of claim 1, The extracting of the 3D shape information from the 2D map information may include converting the contour information into a closed curve by assigning a serial number from the sea level to each contour on the 2D map, and then forming a triangular network between adjacent closed curves. Method of producing a three-dimensional map comprising a. 2. The perspective of claim 1, wherein the correcting step comprises f and L when a focal length of the projector used in the projecting step is f and a distance between the 3D model and the projector is L. 3. (perspective) A method for producing a three-dimensional map, characterized in that the correction using a projection technique. The method of claim 1, wherein the produced 3D map is updated in real time by reflecting changes in terrain and features in the 2D image. The method of claim 1, wherein the two-dimensional image corresponds to any one of an aerial photograph, a satellite photograph, a two-dimensional map, or a computer graphic image. In the apparatus for producing a three-dimensional map, Means for extracting three-dimensional shape information from the two-dimensional map information; Means for converting the extracted three-dimensional shape information into STL (Stereolithography) data; Rapid prototyping means for producing a 3D model based on the STL data; Means for supporting the three-dimensional model; Means for projecting a two-dimensional image corresponding to the two-dimensional map information on the three-dimensional model; And Means for correcting a mismatch between the two-dimensional image and the produced three-dimensional model based on the projection result 3D cartographic apparatus comprising a. 7. The apparatus for producing a three-dimensional map of claim 6, wherein the correction means uses a perspective projection technique of three-dimensional graphics. 7. The apparatus of claim 6, wherein the two-dimensional image is a computer graphic image and can be used as a simulator of computer animation by projecting the two-dimensional image onto the three-dimensional model.