KR20180070070A - System and method for making inundation trace map using unmanned aerial vehicle - Google Patents

Abstract

According to the present invention, an immersion trace map creating method in an immersion trace map creating system using an unmanned aerial vehicle (UAV) includes: a step of obtaining images photographed in a UAV for a selected area among areas where immersion damage occurs by a natural disaster such as typhoon, heavy rain, and tsunami; a step of bonding the obtained images; a step of generating an orthophotograph and a digital surface model (DSM) from the bonded image; a step of generating a 3D topographical map by combining the orthophotograph with the DSM; and a step of calculating and displaying an immersion damage range of the corresponding area of the 3D topographical map. The present invention has an effect of creating an immersion trace map about an immersion damage area quickly and accurately.

Description

TECHNICAL FIELD The present invention relates to a method and system for generating a flood trace using an unmanned aerial vehicle,

More particularly, the present invention relates to a flood traceability technique using an unmanned aerial vehicle.

Recently, natural disasters such as flood damage such as localized heavy rain due to unusual climate change are occurring frequently. The damage caused by natural disasters and the property damage are increasing. The increase of impervious rate due to urban development increases frequency of flooding damage, and property damage is caused by expansion of flooded area.

The disaster guidance of Korea is stipulated in Article 21 of the Natural Disaster Countermeasures Act, Article 18 and 19 of the Enforcement Decree of the same Act, and "National Emergency Management Agency (NEMA), 2013". Among these, the immersion trail is revised and revised so that the immersion trail can be accumulated and managed quickly by investigating the immersion trail whenever a flood damage occurs.

Inundation traces were surveyed and surveyed for flood damage in areas affected by flood damage such as typhoons, heavy rain, and tsunami, and floods, sediment depth, It refers to the map displayed, and is produced and preserved by local governments.

The current flood trail map is visited immediately after the flood damage occurred, and the flooded contents are surveyed. If it is difficult to investigate quickly, the flood trail survey is carried out. However, due to the nature of the flooding damage, it is difficult to conduct the initial survey due to the short duration of immersion, and it is difficult to proceed quickly due to administrative procedures such as budget. It is difficult to construct reliable traces of immersion.

Despite the fact that the flood trail is the basic data for national disaster prevention, there is a problem that the production of the flood trail is delayed due to insufficient budget and management of flood trail management. Therefore, it is necessary to study to reduce the production time and the budget when creating flood trace.

Unmanned Aerial Vehicle (UAV) means an aircraft that does not carry a person on board. In the aviation law of Korea, the term "unmanned aerial vehicle" Of unmanned aerial vehicles or unmanned aerial vehicles, or unmanned aerial crafts of less than 180 kilograms and not exceeding 20 meters in length, excluding the weight of fuel.

Unmanned aerial vehicles are relatively inexpensive and easy to operate, so they have been widely used for military purposes mainly for reconnaissance and targeting in the past. Recently, they have been used extensively in fields of agriculture, fishery, meteorological observation, have. In spite of this widespread use, in the field of surveying, it was relatively limited to detect change of the topography or to grasp the status. In recent years, however, attempts have been made to improve the performance of digital cameras and utilize navigation devices such as GPS (Global Positioning System) / IMU (Inertial Measurement Unit) . Terrain monitoring using such unmanned aerial vehicles is relatively inexpensive to operate and has the advantage that data can be obtained quickly and accurately.

Korean Patent No. 10-1394861

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and system for generating a flood trace using an unmanned airplane in order to more quickly and accurately create a flood trace.

The objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, in the method of creating a flood trace in the flood trace system using the unmanned aerial vehicle (UAV) of the present invention, the flood damage caused by a natural disaster including typhoon, heavy rain, Acquiring images photographed on the unmanned airplane from among the generated regions, joining the acquired images, generating ortho images and DSM (Digital Surface Model) from the joined images, Generating a 3D topographic map by combining the image and the DSM, and calculating and displaying the flood damage range of the area in the 3D topographic map.

And inserting a ground control point (GCP) measured using a GPS (Global Positioning System) in order to reduce an image distortion error due to the image joining in the step of joining the images.

And a step of evaluating the accuracy of the map using the orthometric image and the measurement value at the ground reference point.

In the step of estimating and displaying the flood damage extent, the flood damage range including the flooded area, the flooded depth, and the flooded time of the area can be calculated and displayed.

In the immersion trail mapping system for creating the flooding trace map indicating the flooding damage caused by the natural disaster including the typhoon, heavy rain, and tsunami of the present invention, (UAV) for photographing the area, and the unmanned airplane, acquiring an image taken by the unmanned airplane, joining the acquired images, and extracting ortho-image and DSM (Digital Surface Model), combining the orthoimage and the DSM to generate a 3D topographic map, and calculating and displaying the flood damage range of the corresponding area in the 3D topographical map.

The computer may include a step of inserting a ground control point (GCP), which is measured using a GPS (Global Positioning System), in order to reduce an image distortion error due to image fusion at the time of the image joining.

The computer can evaluate the accuracy of the map by using the orthometric image and the measurement value at the ground reference point.

The computer can calculate the flood damage range including the flooded area, the flooded water depth, and the flooded time in the area.

According to the present invention, by creating a flood trace using an unmanned airplane, it is possible to quickly and accurately create a flood trace for the flooded area.

FIG. 1 is a block diagram illustrating a configuration of a flood trace information generating system using an unmanned aerial vehicle according to an embodiment of the present invention. Referring to FIG.
FIG. 2 is a flowchart illustrating a method of generating a flood trace using an unmanned aerial vehicle according to an embodiment of the present invention.
3 is a view showing an actual unmanned aerial vehicle according to an embodiment of the present invention.
Fig. 4 is a diagram showing the color according to the range of immersion seam. Fig.
FIG. 5 is a view showing flooding traces according to an embodiment of the present invention.
6 is an example of a flight control screen of an unmanned aerial vehicle according to an embodiment of the present invention.
7 is a view illustrating an example of a ground reference point according to an exemplary embodiment of the present invention.
8 is a chart illustrating a ground reference point survey result according to an embodiment of the present invention.
FIG. 9 is a view showing take-off time of an unmanned aerial vehicle according to an embodiment of the present invention.
10 is a diagram illustrating an orthoimage image according to an embodiment of the present invention.
11 is a diagram showing checkpoint coordinate acquisition according to an embodiment of the present invention.
12 is a view showing a state in which a ground reference point is measured according to an embodiment of the present invention.
13 is a chart showing the accuracy evaluation result according to an embodiment of the present invention.
FIG. 14 is a view comparing immersion traces prepared in the past with immersion traces obtained using the unmanned airplane of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted in an ideal or overly formal sense unless expressly defined in the present application Do not.

In the following description of the present invention with reference to the accompanying drawings, the same components are denoted by the same reference numerals regardless of the reference numerals, and redundant explanations thereof will be omitted. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

The present invention relates to a system and a method for generating a flood trace, which is a map showing a flood damage to a flood damage area caused by a natural disaster including a typhoon, a heavy rain, and a tsunami.

FIG. 1 is a block diagram illustrating a configuration of a flood trace information generating system using an unmanned aerial vehicle according to an embodiment of the present invention. Referring to FIG.

Referring to FIG. 1, an immersion trail mapping system using an unmanned aerial vehicle according to an embodiment of the present invention includes an unmanned aerial vehicle (UAV) 10 and a computer 100.

The unmanned airplane (10) is flying over the selected area and photographing the area. The types of the unmanned airplane 10 include a fixed wing unmanned airplane and a winged wing unmanned airplane. According to an embodiment of the present invention, a fixed wing unmanned airplane or a winged wing unmanned airplane can be used to photograph a predetermined area.

The computer 100 communicates with the unmanned air vehicle 10, acquires images taken by the unmanned airplane 10, joins the acquired images, generates ortho images and DSM (Digital Surface Model) from the merged images , A 3D topographic map is created by combining orthoimage and DSM, and a flood trace is created by calculating the extent of flood damage in the 3D topographic map. In the present invention, the computer 100 may include a desktop computer, a laptop computer, a tablet PC, and the like.

In an embodiment of the present invention, the computer 100 inserts a ground control point (GCP), which is measured using a GPS (Global Positioning System), in order to reduce an image distortion error due to image joining, . ≪ / RTI >

Then, the computer 100 can evaluate the accuracy of the flood trace using the measurement value at the ground reference point and the orthoimage image.

In addition, the computer 100 may estimate the flood damage range including the flooded area, the flooded area, and the flooded area of the corresponding area.

FIG. 2 is a flowchart illustrating a method of generating a flood trace using an unmanned aerial vehicle according to an embodiment of the present invention.

Referring to FIG. 6, a ground reference point (GCP) survey is performed for the selected area (S201). In the present invention, it is desirable to select an area where the unmanned aerial photographing is easy if the flood trace is prepared for comparing the immersion traces.

Then, an image photographed by the UAV 10 is acquired for the selected area (S203).

Then, the acquired images are jointed (S205).

In order to reduce the image distortion due to the image joining, a ground reference point (GCP) measured using a GPS (Global Positioning System) is inserted (S207).

Then, a regular image and a DSM (Digital Surface Model) are generated from the combined image (S209).

Then, the accuracy of the map is evaluated using the measurement value at the ground reference point and the orthoimage (S211).

Then, the 3D topographic map is generated by combining the orthoimage and the DSM (S213).

Then, in the 3D topographical map, flood traceability is created by calculating and displaying flood damage range of the area (S215).

In the present invention, the flood damage range including the flooded area, the flooded water depth, and the flooded time in the area can be calculated and displayed in the step S215 of estimating and displaying flood damage range.

Hereinafter, an execution process of creating a flood trace in an actual flood damage area will be described with respect to a flood trace using the unmanned aerial vehicle according to an embodiment of the present invention.

In an embodiment of the present invention, a virtual survey program (VST) was utilized as a utilization method of three-dimensional high-resolution orthoimage using an unmanned airplane, and on July 25, 2006, An analysis of the flooding range for members of Gyeonghyeon-dong, Anseong-si and an analysis of the flooding range for the Yongduri members of Gongdue-ri, Anseong-si, Gyeonggi-do with the heavy rain from July 23 to 26, 2008, .

3 is a view showing an actual unmanned aerial vehicle according to an embodiment of the present invention.

As shown in FIG. 3, a fixed-wing unmanned airplane was used in this embodiment. The photographing optical sensor attached to the unmanned airplane was 12 million pixels. The GPS measurement device for obtaining coordinates was GRX2 of Sokkia Co., Field survey.

The unmanned airplane uses eMotion2, an automatic route setting software, to set the shooting route and shoot the target area along the set flight path. During the shooting, the unmanned aircraft and the operator will be able to recognize the real-time flight status on the notebook screen through the USB ground modem and set the shooting overlap according to the weather conditions. At this time, it is recommended to set the shooting overlap to 60 ~ 75% depending on the weather conditions. In order to prevent distortion of the acquired image, the ground reference point survey is performed to acquire the coordinates of the reference point through the GPS measurement, and coordinates of arbitrary points are generated based on the coordinates of the acquired points, thereby correcting the coordinates of the 3D model do. GPS measurement results are used to reduce the error range of 3D models through post-processing methods. For the image analysis, 2D and 3D topographies were created through Postflight Terra 3D and Virtual Surveyor.

Postflight Terra 3D is a photogrammetry software that enables you to create cm-level orthoimages and DSM (Digital Surface Model) by connecting photographs with LOG data (flight motion data) through a simple setting. Then, through the Virtual Surveyor, Combine the DSM to create a 3D topographic map. GEOID's Virtual Surveyor is a virtual surveillance program that allows you to view multiple layers overlaid and three-dimensional modeling work with TIF images of orthorectic images combined with DEM numerical elevation data.

FIG. 4 is a chart showing hues according to the range of the immersion seam, and FIG. 5 is a diagram showing immersion traces according to an embodiment of the present invention. In Fig. 5 (a), the flooded traces of the Gyeongdong area and (b) the flooded traces of the Yongduri area.

6 is an example of a flight control screen of an unmanned aerial vehicle according to an embodiment of the present invention.

In FIG. 6, (a) is the Hyun-dong area and (b) is the Ping-dong area.

In FIG. 6, the shooting time of the UAV is required to be set within 45 minutes maximum depending on the weather condition, the overlap ratio and the battery condition. Thus, in the case of Hyun-Dong, The aerial photographing area of the unmanned aerial vehicle is 3.25km2 in Gahyeon-dong, 2.17km2 in Yongduri, and the spatial resolution is 4cm / pixel.

FIG. 7 is a view illustrating an example of a ground reference point according to an exemplary embodiment of the present invention, and FIG. 8 is a diagram illustrating a ground reference point survey result according to an exemplary embodiment of the present invention.

As shown in FIGS. 7 and 8, in order to analyze the accuracy of the immersion trail system using an unmanned airplane, the distance was set at about 400 m in the vertical and horizontal directions within the target area, We select the reference points and perform GPS surveying to minimize the image distortion error due to the video mosaic.

FIG. 9 is a view showing take-off of an unmanned aerial vehicle according to an embodiment of the present invention, FIG. 10 is a view showing an orthoimage image according to an embodiment of the present invention, FIG. Fig.

12 is a view showing a state in which a ground reference point is measured according to an embodiment of the present invention. 12, (a) is the Hyun-dong area, and (b) is the Ping-dong area.

The 3D model can be generated without using the ground reference point after photographing the unmanned aerial vehicle used in the present invention. However, in this case, the coordinate error of each point shows error of several tens cm or several meters, and it becomes unreliable to use the virtual surveying program to show the current survey or immersion range. Therefore, in the present invention, ground reference point measurement was performed for each of 26 points (Kwon Hyun-dong) and 11 points (Yong-ri Lee) in order to generate an orthophoto image. As shown in Fig. 12, m-sized airplane signs and road markings were used to obtain coordinate points. The reliability of the data obtained by comparing the coordinates of each point obtained from the 3D model obtained through the series of processes and the ground reference point survey as shown in FIG. 13 is secured.

13 is a chart showing the accuracy evaluation result according to an embodiment of the present invention.

As shown in FIG. 13, the deviations of X, Y, and Z components were 0.08 m, 0.07 m, and 0.04 m on the average of the images obtained at Gyeonghyeon-dong. Horizontal errors showed an average value of less than 7.5cm, and vertical direction showed an average deviation of about 4cm. In case of Yongduri, the deviations of X, Y and Z components were 0.07m, 0.02m and 0.02m, respectively. Horizontal errors showed a mean value of less than 4.5cm, and vertical direction showed a deviation of about 2cm. Since both of the generated ortho images can be read on roads and facilities with an image of about 4.0cm class, it can be used for the production of current survey drawings using ortho images. These results suggest that it is possible to conduct survey using UAV.

FIG. 14 is a view comparing immersion traces prepared in the past with immersion traces obtained using the unmanned airplane of the present invention.

Referring to FIG. 14, the flooded damage area for Gyeonghyun member in 2006 was 617,294 ㎡, and in 2008, about 80,433 ㎡ for Yonghui member. In the present invention, the flooded damage areas using the UAV are 590,982㎡ and 88,409㎡, respectively, which is about 4.27% and 9.91%, respectively. This is probably due to the terrain at the time of the flood damage and the current terrain difference due to the construction after the flooding damage.

As described above, the present invention relates to an efficient production of immersion traces in Korea using an aviation technique of a recently-used unmanned aerial vehicle, and an unmanned aerial vehicle system having advantages such as quick data acquisition and low operation cost (VST) were compared with the flooding traces of Anseong city in Gyeonggi province in 2006 and 2008, and the following results were obtained.

First, as a result of evaluation of the accuracy of the results produced by the unmanned aerial vehicle, the horizontal directional errors showed an average deviation of 7.5 ㎝ and 4.5 ㎝ for each of Gyehyeon-dong and Yongduri, and 4 ㎝ and 2 ㎝ for vertical direction, Since both orthoimages can read the roads and facilities with about 4.0cm class image, it can be used for the production of the current survey drawings using the orthoimage, and the user can freely zoom in , Can be reduced. These results suggest the possibility of surveying using UAV.

Second, the flooding range due to the collapse of the embankment in Gyeonggi - do, Gyeonggi - do, Gyeonggi - do, Anhyeon - dong, Gyeonggi - do, is about 4.27%. Therefore, when using an unmanned aerial vehicle, it is possible to drastically shorten the time required for the basic investigation, the field survey, the field shooting and the post-processing result. Therefore, it can be used for the purpose of acquiring rapid data on disasters and disasters, and to grasp the damage situation.

Third, the utilization of the UAV of the present invention is superior to that of the conventional surveying method in that it is precise and accurate, and thus it can contribute to the establishment of unstructured measures against hydrological hazardous areas. The flood trace can be visually expressed by the user. This is due to the difference between the topography and the current terrain at the time of flood damage, and it is considered that the flood range can be predicted in case of natural disaster by acquiring 3 - D high resolution orthoimage in the area where flooding is expected in the future.

Fourth, if the 3D inundation trace is generated by utilizing the unmanned airplane of the present invention, integrated management on the web can be performed. In addition, the user can collect desired contents more easily and quickly and can be utilized as basic data for various disaster prevention projects It is expected.

While the present invention has been described with reference to several preferred embodiments, these embodiments are illustrative and not restrictive. It will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention and the scope of the appended claims.

10 unmanned aircraft 100 computers

Claims (8)

In the submerged trail mapping method in an immersion trail mapping system using an unmanned aerial vehicle (UAV)
Acquiring an image photographed by the unmanned airplane in a selected area among flood damage caused by a natural disaster including typhoon, heavy rain, and tsunami;
Joining the acquired images;
Generating a regular image and a digital surface model (DSM) from the combined image;
Combining the orthoimage and the DSM to generate a 3D topographic map; And
And calculating and displaying the flood damage range of the area in the 3D topographic map.
The method according to claim 1,
In the step of joining the images,
And inserting a ground control point (GCP), which is measured using a GPS (Global Positioning System), in order to reduce an image distortion error caused by the image joining.
The method of claim 2,
Further comprising the step of evaluating the accuracy of the map using a measurement value at the ground reference point and the orthoimage.
The method according to claim 1,
In the step of estimating and displaying the flood damage range,
Wherein the flood damage range including the flooded ground, the flooded water depth, and the flooded time is calculated and displayed.
In a flood traceability system for creating a flood trace, which is a map showing the flooding damage for flood damage caused by natural disasters including typhoon, heavy rain, and tsunami,
Unmanned Aerial Vehicle (UAV) to shoot the area over the selected area; And
Acquiring an image taken by the unmanned airplane, joining the acquired images, generating an orthoimage image and a DSM (Digital Surface Model) from the jointed image, combining the orthoimage and the DSM To generate a 3D topographic map, and calculating and displaying the flood damage range of the area in the 3D topographic map.
The method of claim 5,
The computer may further include a step of inserting a ground control point (GCP), which is measured using a GPS (Global Positioning System), in order to reduce an image distortion error caused by the image joining at the time of the image joining A flood traceability system.
The method of claim 6,
Wherein the computer evaluates the accuracy of the map using the measurement value at the ground reference point and the orthoimage.
The method of claim 5,
Wherein the computer calculates and displays the flood damage range including the flooded ground, the flooded water depth, and the flooded time of the corresponding area.

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