JP2019106000A - Method and program for determining safety of a flight course of aircraft - Google Patents

Abstract

To provide a technology capable of easily determining safety of a flight course of an aircraft.SOLUTION: A method for determining safety of a flight course of an aircraft includes the steps of: acquiring a first model including height information of a ground object in each of multiple regions dividing a predetermined area (step S2010); generating a second model by expanding the height information of the ground object in each region specified in the first model due to a predetermined distance (step S2040); receiving input of the flight course of an aircraft scheduled in the predetermined air (step S2050); comparing the second model to the flight course to determine whether a distance between the flight course and the ground object is less than the predetermined distance (step S2060); and outputting a determination result (step S2070).SELECTED DRAWING: Figure 20

Description

  This disclosure relates to aircraft, and more particularly, to techniques for determining flight path safety of an aircraft.

  In recent years, with the development and spread of aircraft technology represented by unmanned aerial vehicles, various usage methods of aircraft have been realized and proposed. For example, aerial photography and pesticide spraying using unmanned aerial vehicles have already been realized. In addition, research and development for the realization of passenger transportation and goods transportation by automatic flight of small aircraft are being promoted.

  In addition, aviation laser surveying which examines the shape of a feature (all things on the ground regardless of natural and artificial) using an aircraft has been put to practical use (patent documents 1 to 3). In the aviation laser survey, a laser scanner mounted on an aircraft emits a laser beam to the ground, and the distance to the feature calculated from the time taken to receive the laser beam reflected from the feature and the position information of the aircraft It is a technology to check the shape (height) of a feature based on it.

Unexamined-Japanese-Patent No. 2016-212000 JP, 2011-158278, A JP 2004-144524 A

As noted above, the momentum for industrial use of aircraft in a wider range of fields is growing. In this way, as the range of use of aircraft expands, it is necessary to set a flight route with a sufficient distance to features in view of legal requirements or safety when actually operating the aircraft. is there.
On the other hand, if the distance between the aircraft and the feature is too large, it may be inconvenient in light of the purpose of the operation. For example, if the detour is made larger than necessary to avoid the feature, the flight time is extended by that amount, which is inconvenient for the operation for the purpose of a short flight, such as transportation. In addition, if you climb higher than necessary to avoid features, the altitude to the ground will be increased by that much, which is inconvenient for the operation for the purpose of air flight and other low air flight. Therefore, in order to ensure safety and efficiently and effectively satisfy the operation purpose, it is necessary to appropriately set the distance between the aircraft and the feature.

  The present disclosure has been made to solve the problems as described above, and an object in one aspect is to provide a technology capable of easily determining the safety of a planned flight path of an aircraft.

  According to an embodiment, a method is provided for determining flight path safety of an aircraft. This method comprises the steps of acquiring a first model including height information of features of each of a plurality of regions dividing a predetermined area, and each of the regions defined in the first model based on a predetermined distance. Step of expanding the feature height information of each to generate a second model, receiving an input of a flight path of an aircraft scheduled in a predetermined area, and comparing the second model with the flight path Determining whether the distance between the flight path and the feature is less than a predetermined distance, and outputting the determination result.

  The method according to an embodiment may simply determine whether the flight path of the aircraft is safe.

  The above and other objects, features, aspects and advantages of the disclosed technical features will be apparent from the following detailed description of the invention taken in conjunction with the accompanying drawings.

It is a figure showing an example of the composition of the system according to an embodiment. It is a block diagram showing an example of composition of a computer. Represents an ortho image. It is a figure which represents the data structure of a numerical surface layer model typically. It is a figure showing an example of a data structure of a numerical surface model. It is a figure which expresses a numerical surface model visually. It is a figure showing the flight path typically. It is a figure showing an example of the data structure of a flight path. It is a figure for demonstrating the outline | summary of the method of judging the safety of a flight path. It is a figure showing an example of the data structure of a buffer model. It is a figure which represents the buffer model shown by FIG. 10 visually. It is a figure showing the other example of the data structure of a buffer model. It is a figure which represents the buffer model shown by FIG. 12 visually. It is a figure showing typically an example of processing which generates an extended model. It is a figure for demonstrating the specific example of the process shown by FIG. It is a figure which compares a numerical surface model and an extended model visually. It is a figure showing typically another example of processing which generates an extended model. FIG. 18 is a diagram for describing a specific example of the process shown in FIG. 17; It is a figure showing an example of the user interface displayed on a display. It is a flowchart showing an example of the processing which judges the safety of a flight path.

  Hereinafter, embodiments of this technical concept will be described in detail with reference to the drawings. In the following description, the same components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description about them will not be repeated. In addition, each embodiment and each modification which are explained below may be combined suitably suitably.

[Technical thought]
First, technical ideas in accordance with the present disclosure will be described. The technology according to the embodiment acquires a numerical surface model (first model) of an observation area by a test flight of an aircraft or the like. The numerical surface layer model includes the heights of features of each of a plurality of regions constituting the observation area. The altitude of the test flight is set high (for example, 100 m). This reduces the possibility of a collision between the aircraft and the feature.

  The technology according to the embodiment is that each height defined in the numerical surface model is based on the distance between the aircraft and the feature (hereinafter also referred to as “safety distance”) set according to the safety standard (for example, the aviation law). Correction (expansion) to generate an expanded model.

  Next, the technology according to the embodiment receives an input of a flight path of an aircraft to fly in the observation area. The altitude of this flight path is set lower than the altitude of the test flight. The technique according to the embodiment compares the altitude at each point of the input flight path with the altitude defined in the extended model corresponding to the point, and determines whether the input flight path secures a safe distance. And output the judgment result.

  The technology according to such an embodiment can easily determine whether the flight path of the aircraft is safe. Hereinafter, specific configurations and processes necessary to realize the technology will be described.

  Hereinafter, although the unmanned aerial vehicle is described as an example of the aircraft according to the present disclosure, the above technical idea is naturally applicable to the determination of the safety of the planned flight path of a manned aircraft. In addition, the aircraft may include one having an engine such as an airplane or a helicopter, one not having an engine such as a balloon, a flying object, and the other generally moving in the air. The projectile may include, for example, a rocket, a drone, a flying object operated by a radio control, and the like.

[System overview]
FIG. 1 is a diagram illustrating an example of a configuration of a system 100 according to an embodiment. System 100 includes an unmanned aerial vehicle 110 and a computer 120.

  The unmanned aerial vehicle 110 and the computer 120 are configured to be connectable wirelessly or by wire. The computer 120 stores the flight path in storage (not shown) of the unmanned aerial vehicle 110. The unmanned aerial vehicle 110 observes features with a camera (not shown) and a laser scanner (not shown) while flying along this flight path.

  When performing aerial photography and surveying using such unmanned aerial vehicle 110, it is necessary to set the unmanned aerial vehicle 110 a flight path with a sufficient distance to a feature in view of legal requirements or safety.

  On the other hand, if the distance between the unmanned aerial vehicle 110 and the feature is too large, the resolution of the observation result is lowered. Therefore, in order to obtain observation results with high resolution while securing safety, it is necessary to appropriately set the distance between the unmanned aerial vehicle 110 and the feature. Hereinafter, techniques that can solve such problems will be described.

[Computer 120]
FIG. 2 is a block diagram showing an example of the configuration of the computer 120. As shown in FIG. The computer 120 includes a central processing unit (CPU) 210, a random access memory (RAM) 220, a read only memory (ROM) 230, a hard disk drive (HDD) 240, an input device 250, a display 260, and an input. An interface (I / F) 270 and a communication I / F 280 are included. These devices are connected to one another by a bus.

  The ROM 230 stores a control program 232. The HDD 240 stores a numerical surface layer model 242, an orthoimage 244, and a flight path 246. Details of these data will be described later.

  The CPU 210 functions as a control device that controls the operation of the computer 120. The CPU 210 further executes a control program stored in the ROM 230 to determine whether the flight path 246 is safe. Details of this process will be described later.

  The RAM 220 functions as a working memory when the CPU 210 executes a program.

  The input device 250 receives user input. The input device 250 is realized by, for example, a mouse, a keyboard, or another input device.

  The input I / F 270 is configured to be able to read information stored in a CD (Compact Disc), a DVD (Digital Versatile Disc), a USB (Universal Serial Bus) memory, and other external storage devices.

  The communication I / F 280 is, for example, a wireless local area network (LAN) card. The computer 120 is configured to be communicable with the unmanned aerial vehicle 110 connected to a LAN or a wide area network (WAN) via a communication I / F 280 and an external device.

  The above-described numerical surface model 242, ortho image 244 and flight path 246 may be stored in HDD 240 via input I / F 270 or communication I / F 280.

[Numerical surface model 242]
FIG. 3 depicts ortho image 244. The ortho image 244 is an aerial photograph of an area (hereinafter also referred to as “observation area”) that the unmanned aircraft 110 will observe from now on.

  In ordinary aerial photography, due to the difference in the distance from the center of the lens to the object, the object appears to be inclined outward from the center of the photograph from the center of the photograph toward the periphery. An ortho image obtained by orthographic conversion of a normal aerial photograph shows an object without tilt as viewed from directly above.

  FIG. 4 is a view schematically representing the data structure of the numerical surface layer model 242. As shown in FIG. The numerical surface model 242 includes height information of features of each of a plurality of regions dividing the observation area horizontally. That is, the numerical surface model 242 can be said to be a model of the height of the earth surface including buildings and trees in the observation area. The numerical surface model is also referred to as DSM (Digital Surface Model). This height information represents the height above sea level, ellipsoidal height, or some other reference plane.

  As an example, the numerical surface layer model 242 includes information on the height of each area (pixel) arranged in a matrix in the row direction (x direction) and the column direction (y direction) in the observation area. The area of each region may be set to be the same as one another.

  Further, the numerical surface layer model 242 includes intervals (ΔEx, ΔNx) in the geographical coordinate system of the regions adjacent to each other in the x direction, and intervals (ΔEy, ΔNy) in the geographical coordinate system of the regions adjacent to each other in the y direction. The geographical coordinate system functions as a coordinate system for representing points on the earth, and is represented by longitude and latitude as an example. These intervals substantially represent the size in the geographical coordinate system (real world) of each area. As an example, each area is set to 1 m square.

  In one aspect, the numerical surface model 242 may be defined based on a model having higher resolution than the numerical surface model 242. In such a case, the height information defined in each area of the numerical surface layer model 242 is set to the highest height information among the plurality of height information included in the area.

  The numerical surface model 242 further includes geographical coordinates {E (0, 0), N (0, 0)} in the area located at (x, y) = (0, 0).

In such a case, the geographical coordinates of each area are calculated by the following formula.
E (x, y) = E (0, 0) + ΔEx × x + ΔEy × y
N (x, y) = N (0, 0) + ΔNx × x + ΔNy × y
FIG. 5 shows an example of the data structure of the numerical surface layer model 242. As shown in FIG. The numerical surface layer model 242 has position (x, y) and height information (z) in the matrix for each area, and has information of the geographical coordinate system as a header. As an example, such a numerical surface model 242 is defined in GeoTIFF (Geo Tagged Image File Format) format.

  FIG. 6 is a diagram visually representing the numerical surface layer model 242. As shown in FIG. Although height information is defined as a numerical value (altitude of a feature) in FIGS. 4 and 5, in FIG. 6, height information (a numerical value represented by the height information) is defined as a color (or a mere gradation). Thereby, the user can intuitively understand the height of the feature in the observation area. The image shown in FIG. 6 is also referred to as a raster image.

  The numerical surface layer model 242 representing the height of the feature in the observation area described above is acquired in advance by test flight of the unmanned aerial vehicle 110 set at a high altitude in a certain phase. In another aspect, the numerical surface layer model 242 may be acquired based on a past observation result, a three-dimensional model based on a construction drawing or the like.

[Flight route]
FIG. 7 schematically shows the flight path 246. As shown in FIG. In the example shown in FIG. 7, the flight path 246 is superimposed on the ortho image of the observation area. The flight path 246 is defined by a straight line connecting a plurality of path points P1, P2,.

  FIG. 8 is a diagram illustrating an example of a data structure of flight path 246. Referring to FIG. The flight path 246 has geographic coordinates (E, N) and an altitude Z for each of a plurality of path points. In the example shown in FIGS. 7 and 8, the flight path 246 is configured to connect straight lines extending north to south at a predetermined interval (for example, 15 m).

[How to generate an extension model]
FIG. 9 is a diagram for describing an overview of a method of determining the safety of flight path 246. Referring to FIG. In FIG. 9, in order to make the description easy to understand, the feature is represented by a cross-sectional view when viewed from the horizontal direction.

  The line 910 shown in FIG. 9 represents the shape of the actual feature. Line 920 represents numerical surface model 242. The numerical surface layer model is expressed by the height information of the feature surface in each region (point), and therefore can not represent the concave portion of the feature that is recessed horizontally.

  The CPU 210 expands the feature height information of each area defined in the numerical surface layer model 242 so that the distance to the feature is equal to or more than the safe distance Ds, based on the safe distance Ds. A model obtained by extending the numerical surface model 242 is defined as an extended model 930. That is, the extended model 930 has the same region (x, y) as the numerical surface layer model 242. Further, the geographical coordinate system defined by the extended model 930 is the same as the geographical coordinate system defined by the numerical surface layer model 242.

  If the height at each point (point on the line connecting the route point and the route point) of the flight route 246 is lower than the height (height information) defined in the extended model 930 corresponding to the location, the CPU 210 determines the flight route It is determined that the distance between 246 and the feature is less than the safe distance Ds. The CPU 210 determines that the flight path 246 is not safe when the distance between the flight path 246 and the feature is less than the safe distance Ds. In the example shown in FIG. 9, the height of the portion of the flight path 246 indicated by a two-dot chain line is lower than the height defined in the extended model 930.

  The safety distance Ds is set according to the safety standard, the observation target, the observation purpose, and the like. For example, Japan's aviation law stipulates that the unmanned aircraft and the third party property (features) must be kept at a distance of 30 m or more (the aviation law No. 132). Article 2-3, Article 236-4 of the Ordinance for Enforcement of the Aviation Act. Therefore, the safety distance Ds can be set to 30 m. In one aspect, computer 120 receives an input of safe distance Ds from the user via input device 250. In another aspect, the safety distance Ds may be set in advance.

  In one aspect, the CPU 210 generates a buffer model 940 based on the safe distance Ds. The buffer model 940 includes height correction information for each of a plurality of areas dividing the predetermined shape. Details of the buffer model 940 will be described later. The CPU 210 generates an extended model 930 based on the numerical surface layer model 242 and the buffer model 940.

  The reason why the buffer model 940 is used is that, if a model obtained by simply adding the safety distance Ds to the height information of each area specified in the numerical surface model 242 is used as the extension model, And the distance between the two and may be less than the safety distance Ds.

  In the example shown in FIG. 9, the value obtained by adding the safety distance Ds to the height information z1 of the area (x, y) = (x1, y1) close to the building of the numerical surface layer model 242 is the area (x1, x1 in the extended model When the height information Z1 ′ of x1) is set, the distance between the coordinates (x1, y1, Z1 ′) and the building becomes less than the safety distance Ds.

  Therefore, the CPU 210 sets the height information of the area (x1, x1) in the extended model 930 to Z1 based on the buffer model 940. In such a case, the distance between the coordinates (x1, x1, Z1) and the building is equal to or greater than the safety distance Ds. Specific processing for generating the extended model 930 will be described later.

  According to the configuration, the CPU 210 can make the flight path 246 safe only by comparing the altitude at each point of the flight path 246 with the altitude (height information) defined in the extended model 930 corresponding to the point. It can be easily determined whether there is any.

  In one aspect (e.g., when flight path 246 is determined to be unsafe), flight path 246 is changed. In such a case, the CPU 210 can determine whether or not the flight path 246 after the change is safe by merely performing the above comparison processing on the flight path 246 after the change using the expanded model 930 already generated.

  As a comparison of the method according to the embodiment, a method of determining whether the distance between the flight path 246 and the feature is less than the safe distance Ds without generating the extended model 930 (hereinafter, also referred to as “comparison method”) explain. In such a case, the CPU 210 must specify, for each point in the flight path 246, the range of the sphere whose radius is the safe distance Ds, and determine whether or not there is a feature within the range. In the example shown in FIG. 9, the CPU 210 determines that the point 960 is equal to or greater than the safety distance Ds because the ball 970 whose radius is the safety distance Ds and the numerical surface model 242 do not contact with the point 960 of the flight path 246. It is determined that

  The amount of calculation in the comparison method is much larger (for example, 100 times or more) than the amount of calculation in the method according to the embodiment. Also, the comparison method needs to execute this huge calculation again when the flight path 246 is changed.

[How to generate an extension model]
Hereinafter, specific processing of the method of generating the extension model will be described. First, the buffer model will be described.

(Buffer model)
FIG. 10 is a diagram illustrating an example of the data structure of the buffer model. FIG. 11 is a view visually representing the buffer model shown in FIG. 10 using the same method as that of FIG. 6 described above. The buffer model shown in FIG. 10 includes height correction information for each of a plurality of areas for dividing a circle. The regions constituting the buffer model are arranged in the row direction (Δx direction) and the column direction (Δy direction). An area at the center of this circle is defined as (Δx, Δy) = (0, 0), that is, as an origin. The size of each area in the geographic coordinate system is set to the same size (eg, 1 m square) as each area of the numerical surface layer model 242.

  The height correction information (Δz) defined in each region corresponds to the height of a hemisphere whose center is (Δx, Δy) = (0, 0) and whose radius is the safe distance Ds. In this sense, the buffer model shown in FIG. 10 can also be said to be a hemispherical model with the safe distance Ds as the radius.

  In the example shown in FIG. 10, the safe distance Ds is set to 4 m. Therefore, the height correction information (Δz) of the area (Δx, Δy) = (0, 0) is defined as 4, and the number of areas extending in the axial direction from the center of the circle is set to 4 ( The size of each area is set to 1 m square). Further, the height correction information defined in each area becomes smaller according to the inclination of the hemisphere (semicircle) as it goes away from the center.

  When an extended model 930 is generated by performing processing to be described later using such a hemispherical model, the distance between each coordinate specified in the extended model 930 and the feature surface defined in the numerical surface layer model 242 is a safety distance Become a Ds.

  The buffer model is not limited to the hemispherical model shown in FIG. FIG. 12 is a diagram illustrating another example of the data structure of the buffer model. FIG. 13 visually represents the buffer model shown in FIG. The buffer model shown in FIG. 12 includes height correction information for each of a plurality of areas dividing a rectangle (here, a square). The respective regions constituting the buffer model are arranged in a matrix in the row direction (Δx direction) and the column direction (Δy direction). An area at the center of this rectangle is defined as (Δx, Δy) = (0, 0), that is, as an origin.

  The height correction information (Δz) defined in each area is set to the safety distance Ds. In this sense, the buffer model shown in FIG. 12 can be said to be a rectangular parallelepiped model whose height is the safe distance Ds.

  In the example shown in FIG. 12, the safety distance Ds is set to 5 m. In addition, the size of each area is set to 5/3 m square. Therefore, the height correction information (Δz) of each area is defined as 5, and the number of areas extending in the axial direction from the center of the rectangle is set to three.

  When the extended model 930 is generated by performing processing to be described later using such a rectangular parallelepiped model, the distance between each coordinate specified in the extended model 930 and the surface of the feature specified in the numerical surface layer model 242 is a safety distance It becomes more than Ds.

(Process of generating extended model)
<First method>
FIG. 14 is a diagram schematically illustrating an example of a process of generating an extended model. In the example shown in FIG. 14, the buffer model 940 is a hemispherical model.

  The CPU 210 executes the following calculation with each region of the numerical surface layer model 242 as a reference. Hereinafter, an area used as a reference of the calculation is defined as a "area of interest". The CPU 210 adds the height information zn (xn, yn) of the attention area (xn, yn) to each of the height correction information Δz (Δx, Δy) defined in each area of the buffer model 940. The CPU 210 sets the height of each of a plurality of regions corresponding to the shape of the buffer model 940 with the addition result zn (xn, yn) + Δz (Δx, Δy) as a reference region (xn, xn) of the extended model 930. It is set as information Z (xn + Δx, yn + Δy).

  In one aspect, height information may already be set in a predetermined area of the expansion model 930. In such a case, the CPU 210 updates the height information of the predetermined area to the addition result only when the calculated addition result of the predetermined area is higher than the already set height information.

  The CPU 210 generates the extended model 930 by repeatedly executing the above-described processing, with each region constituting the numerical surface layer model 242 as a region of interest.

  FIG. 15 is a diagram for describing a specific example of the process shown in FIG. In one aspect, it is assumed that a buffer model 940 and a numerical surface model 242 are defined as shown in FIG. The buffer model 940 shown in FIG. 15 has five (Δx, Δy) = (0, 0), (1, 0), (0, 1), (−1, 0) and (0, −1). It is a hemispherical model having a region.

  The CPU 210 first sets a region of (x, y) = (0, 0) of the numerical surface layer model 242 as a region of interest. In this case, the CPU 210 sets height information of a plurality of areas corresponding to the shape of the buffer model 940 based on the area (x, y) = (0, 0) of the expansion model 930 corresponding to the area of interest. . The plurality of regions are expressed by (0 + Δx, 0 + Δy). Also, x and y are not set to negative values. Therefore, the plurality of regions are (x, y) = (0, 0), (1, 0), (0, 1).

  The CPU 210 corrects the height information of the area (x, y) = (0, 0) in the extended model 930 and the height correction of the area (Δx, Δy) = (0, 0) of the buffer model 940 corresponding to the area. It is set to "5" which added height information "3" of attention area to information "2". Similarly, the CPU 210 sets the height information of the area (x, y) = (0, 1) in the extended model 930 to the area (Δx, Δy) = (0, 1) of the buffer model 940 corresponding to the area. It sets to "4" which added height information "3" of attention area to height correction information "1" of. The CPU 210 corrects the height information of the area (x, y) = (1, 0) in the extended model 930 and the height correction of the area (Δx, Δy) = (1, 0) of the buffer model 940 corresponding to the area. It sets to "4" which added height information "3" of attention area to information "1". As a result, an expanded model 930 shown in state 1530 is obtained.

  Next, the CPU 210 sets (x, y) = (1, 0) of the numerical surface layer model 242 as a region of interest. In this case, the CPU 210 sets a plurality of areas (x, y) = (corresponding to the shape of the buffer model 940) based on the area (x, y) = (1, 0) of the expanded model 930 corresponding to the area of interest. Set the height information of (1, 0), (2, 0), (1, 1), (0, 0).

  The CPU 210 corrects the height of the area (Δx, Δy) = (0, 0) of the buffer model 940 corresponding to the area as height information of the area (x, y) = (1, 0) in the extended model 930 The height information “7” of the attention area is added to the information “2” to calculate “9”. The height information “4” of the area (x, y) = (1, 0) in the extended model 930 is already set by the above-described processing. Therefore, the CPU 210 compares the calculation result "9" with the height information "4" already set, and determines that the calculation result "9" is higher. Therefore, the CPU 210 updates the height information of the area (x, y) = (1, 0) in the extended model 930 to the calculation result “9”.

  Similarly, the CPU 210 sets height information of areas (x, y) = (2, 0), (1, 1), (0, 0) in the extended model 930 to “8”, “8”, “ Set each to 8 ". As a result, an expanded model 930 shown in state 1540 is obtained. The CPU 210 generates the extended model 930 by repeating the above-described process.

  The process of generating the above-described extended model can be generalized as follows. The CPU 210 defines height information of each of a plurality of areas corresponding to a predetermined shape (for example, a circle, a rectangle) of a buffer model based on a predetermined area (corresponding to the area of interest) of the extended model in the corresponding buffer model. Height information is added to the height information of the region of interest of the numerical surface layer model. At this time, when height information has already been set in any of a plurality of regions of the extended model, the CPU 210 has already set height information corresponding to the addition result of the region. When the height is higher than the height, height information corresponding to the addition result is set as height information in the area.

  FIG. 16 is a diagram visually comparing the numerical surface layer model 242 and the extended model 930. In FIG. 16, the height of the bright part is high and the height of the dark part is low. It can be seen from FIG. 16 that the extended model 930 is brighter as a whole, that is, the altitude is higher than that of the numerical surface model 242.

<Second method>
FIG. 17 is a diagram schematically illustrating another example of the process of generating the extension model. In the example shown in FIG. 17, the buffer model 940 is a hemispherical model.

  The CPU 210 specifies height information z (xn + Δx, yn + Δy) of each of a plurality of regions (xn + Δx, yn + Δy) corresponding to the shape 1710 of the buffer model 940 based on the region of interest (xn, yn) of the numerical surface layer model 242 Do. The CPU 210 adds the corresponding height correction information Δz (Δx, Δy) of the buffer model to each of the height information. The CPU 210 sets the height information of the region of interest (xn, yn) of the extended model 930 to the highest height information among the addition results z (xn + Δx, yn + Δy) + Δz (Δx, Δy).

  The CPU 210 generates the extended model 930 by repeatedly executing the above-described processing, with each region constituting the numerical surface layer model 242 as a region of interest.

  FIG. 18 is a diagram for describing a specific example of the process shown in FIG. The buffer model 940 and the numerical surface model 242 shown in FIG. 18 are the same as those shown in FIG.

  The CPU 210 first sets a region of (x, y) = (0, 0) of the numerical surface layer model 242 as a region of interest. The CPU 210 specifies a plurality of areas corresponding to the shape of the buffer model 940 based on the area of interest. The plurality of regions are expressed by (0 + Δx, 0 + Δy). Also, x and y are not set to negative values. Therefore, the plurality of regions are (x, y) = (0, 0), (1, 0), (0, 1).

  The CPU 210 adds the corresponding height correction information of the buffer model 940 to the height information defined in each of the plurality of specified areas, to generate an intermediate model 1810.

  More specifically, the CPU 210 corrects the height of the area (0, 0) of the buffer model 940 corresponding to the height information “3” of (x, y) = (0, 0) of the numerical surface layer model 242 Information “2” is added to set height information of area (x, y) = (0, 0) of the intermediate model 1810 to “5”. The CPU 210 adds the height correction information “1” of the area (1, 0) of the corresponding buffer model 940 to the height information “7” of (x, y) = (1, 0) of the numerical surface layer model 242 Then, height information of the area (x, y) = (1, 0) of the intermediate model 1810 is set to “8”. The CPU 210 adds the height correction information “1” of the area (0, 1) of the corresponding buffer model 940 to the height information “2” of (x, y) = (0, 1) of the numerical surface layer model 242 Then, height information of the region (x, y) = (0, 1) of the intermediate model 1810 is set to “3”.

  The CPU 210 sets “8”, which is the highest among the height information set in each area of the intermediate model 1810, to the height information of the attention area (0, 0) of the extended model 930. As a result, an expanded model 930 shown in state 1820 is obtained.

  Next, the CPU 210 sets an area of (x, y) = (1, 0) as the area of interest. The CPU 210 specifies a plurality of areas corresponding to the shape of the buffer model 940 based on the area of interest. The plurality of regions are (x, y) = (1, 0), (2, 0), (1, 1), (0, 0).

  The CPU 210 adds the corresponding height correction information in the buffer model 940 to the height information defined in each of the plurality of specified areas, and generates an intermediate model 1830. Specifically, the CPU 210 sets the height information of the area (x, y) = (1, 0), (2, 0), (1, 1), (0, 0) of the intermediate model 1830 to “9”. , "8", "7" and "4" respectively.

  The CPU 210 sets “9”, which is the highest among the height information set in each area of the intermediate model 1830, as the height information of the attention area (1, 0) of the extended model 930. As a result, an expanded model 930 shown in state 1840 is obtained. The CPU 210 generates the extended model 930 by repeating the above-described process.

  In the above, the area of the intermediate model is defined in order to make the description easy to understand, but the CPU 210 expands only the plurality of height information defined in the intermediate model in the RAM 220 or the like, and the plurality of height information Can be configured to select the highest height information among them.

  The process of generating the above-described extended model can be generalized as follows. The CPU 210 adds the corresponding height correction information of the buffer model to the height information defined in each of the plurality of areas corresponding to the predetermined shape of the buffer model based on the attention area of the numerical surface layer model. The CPU 210 sets the height of the region of interest in the extended model to the highest height information among height information of each of the plurality of regions corresponding to the predetermined shape after the addition.

  The above-described buffer model 940 is configured in line symmetry with each of the Δx axis and the Δy axis. In such a case, an extended model obtained by the method (also referred to as “the second method”) described in FIGS. 17 and 18 and an extended model obtained by the method (also referred to as the “first method”) described in FIGS. It will be the same as the model.

  As shown in FIGS. 15 and 18, the second method accesses the memory (for example, the RAM 220 and the ROM 230) defining the extended model 930 less frequently than the first method. Therefore, when it takes time to read and write height information of the extended model 930, the second method can shorten the processing time more than the first method.

[Presentation of judgment result]
The CPU 210 compares the generated extended model 930 with the flight path 246 to determine whether the distance between the flight path 246 and the feature is less than the safe distance Ds, that is, whether the flight path 246 is dangerous or not. Do.

  More specifically, CPU 210 converts region (x, y) of extended model 930 into geographic coordinate system (E, N) (that is, the same horizontal coordinate system as flight path 246) by the method described above. The CPU 210 determines whether the altitude at each point of the flight route 246 (point on the line connecting the route point and the route point) is less than the altitude (height information) defined in the extended model 930 corresponding to the point. to decide.

  In another aspect, the CPU 210 converts the geographical coordinate system (E, N) of the flight path 246 into the coordinate system of (x, y), and compares the converted flight path 246 with the expanded model 930. It is also good.

  The CPU 210 outputs the determination result to the user. Hereinafter, although the process which outputs a judgment result to the display 260 as an example is demonstrated, an output method is not restricted to this. For example, the CPU 210 may output the determination result to the user by voice using a speaker (not shown).

  FIG. 19 is a diagram illustrating an example of a user interface displayed on the display 260. In one aspect, the CPU 210 displays the determination result on the display 260.

  The display 260 includes a preview screen 1910, a switch button 1930, a correction button 1940, and a save button 1950.

  In the example shown in FIG. 19, the CPU 210 displays on the display 260 a preview screen 1910 in which the numerical surface layer model 242 represented as an image, the ortho image 244 and the flight path 246 are superimposed.

  The CPU 210 determines that the distance between the path 1925 and the feature in the flight path 246 is less than the safe distance Ds. The CPU 210 displays, on the display 260 (preview screen 1910), a path 1925 in which the distance to the feature is less than the safe distance Ds and another path which is the safe distance Ds or more among the flight paths 246. For example, the CPU 210 displays these in different colors. According to the configuration, the user can understand at a glance the path 1925 in the flight path 246 where the distance to the feature is less than the safe distance Ds.

  The user may select the switch button 1930, the correction button 1940, and the save button 1950 via the input device 250.

  The CPU 210 changes the content displayed on the preview screen 1910 according to the selection of the switching button 1930. As an example, in response to the selection of switching button 1930, CPU 210 sequentially switches the content displayed on preview screen 1910 among the following first content to fourth content. In the first to fourth contents, it is assumed that the numerical surface layer model 242 is represented as an image as shown in FIG.

First content: flight path 246
Second content: ortho image 244 and flight path 246
Third content: Numerical surface model 242 and flight path 246
Fourth content: Numerical surface model 242, ortho image, and flight path 246
In one aspect, the CPU 210 superimposes an image displayed in each content and displays it on the preview screen 1910.

  The CPU 210 receives the correction of the flight path 246 in response to the selection of the correction button 1940. Specifically, the CPU 210 is configured to be able to receive an instruction to correct the position of a route point constituting the flight route 246 or an instruction to newly add a route point.

  For example, the user adds route points to the start point and the end point of the route 1925 while looking at the preview screen 1910, and corrects the heights of these route points to increase the distance between the changed route 1925 and the feature. Set the safety distance Ds or more.

  In response to the selection of the save button 1950, the CPU 210 saves the changed flight path 246 in the HDD 240. In another aspect, CPU 210 may transmit modified flight path 246 to unmanned aerial vehicle 110 connected via communication I / F 280 in response to the selection of save button 1950.

[Other configuration]
In the above example, CPU 210 is configured to accept changes in flight path 246, but may be configured to automatically correct flight path 246 in other embodiments.

  For example, when the CPU 210 determines that the distance between the route 1925 and the feature in the flight route 246 is less than the safe distance Ds, the distance to the feature is equal to or greater than the safe distance Ds based on the extended model 930 Modify path 1925 to

  In one aspect, the CPU 210 changes the height of the path 1925 to the height (height information) of the extended model 930 corresponding to the path. According to the above, it is possible to save the trouble of the user performing the process of changing the flight path.

  In another aspect, the CPU 210 changes geographical coordinates (E, N) while maintaining the height of the path 1925. In the unmanned aerial vehicle, generally, the moving speed in the vertical direction (vertical direction) is set slower than the moving speed in the horizontal direction. Therefore, the CPU 210 can suppress the decrease in the moving speed of the unmanned aerial vehicle 110 by changing the geographical coordinates (E, N) while maintaining the altitude of the route 1925.

Control structure
FIG. 20 is a flowchart showing an example of processing for determining the safety of the flight path. Each process shown in FIG. 20 can be realized by CPU 210 executing control program 232 stored in ROM 230.

  At step S2010, CPU 210 obtains numerical surface layer model 242 and orthoimage 244 of the observation area. These data are acquired, for example, by the pre-test flight of the observation area by the unmanned aerial vehicle 110.

  In step S2020, CPU 210 receives an input of safe distance Ds from the user via input device 250.

  In step S2030, CPU 210 generates buffer model 940 based on safe distance Ds.

  In step S2040, CPU 210 generates extended model 930 based on numerical surface layer model 242 and buffer model 940.

  In step S2050, CPU 210 receives an input of flight path 246 scheduled for the flight of unmanned aerial vehicle 110 from now. The CPU 210 may receive an input of the flight path 246 via the input device 250, the input I / F 270, or the communication I / F 280.

  The CPU 210 compares the extension model 930 with the flight path 246 to determine whether the distance between the flight path 246 and the feature is less than the safe distance Ds.

  The CPU 210 outputs the flight path 246 and the determination result to the display 260. The CPU 210 may further execute processing of changing the flight path 246 in accordance with the user's instruction, processing of switching the content displayed on the display 260, and the like.

  According to the above, the method according to the embodiment can easily determine (with a small amount of calculation) whether the flight path of the aircraft is safe regardless of unmanned / manned person. Thus, for example, when the aircraft is used for surveying purposes, the user can acquire high resolution observation results while securing safety for the flight of the aircraft. In addition, according to the method according to the embodiment, the user can easily set the shortest flight path to the safe destination.

  It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is indicated not by the above description but by the claims, and is intended to include all the modifications within the meaning and scope equivalent to the claims.

  100 systems, 110 unmanned aerial vehicles, 120 computers, 220 RAM, 230 ROMs, 232 control programs, 242 numerical surface models, 244 ortho images, 246 flight paths, 250 input devices, 260 displays, 910, 920 lines, 930 expansion models, 940 Buffer model, 1910 preview screen, 1925 path, 1930 switch button, 1940 correction button, 1950 save button, Ds safe distance, P1, P2 path point.

Claims (11)

A method for determining the safety of an aircraft flight path, comprising:
Acquiring a first model including height information of features of each of a plurality of areas dividing the predetermined area;
Expanding the feature height information of each of the regions defined in the first model based on a predetermined distance to generate a second model;
Accepting an input of a flight path of the aircraft scheduled in the predetermined area;
Comparing the second model with the flight path to determine whether the distance between the flight path and the feature is less than the predetermined distance;
Outputting the determination result.   The method according to claim 1, wherein the step of outputting the determination result includes displaying the input flight path and the determination result on a display.   The displaying on the display is performed in a manner different from the part in which the distance to the feature in the input flight path is less than the predetermined distance and the part in which the distance is equal to or more than the predetermined distance. The method of claim 2, comprising displaying on a display. The method further comprises the step of acquiring an ortho image of the predetermined area,
The method according to claim 2, wherein displaying on the display includes displaying the acquired orthoimage and the input flight path on the display in an overlapping manner.   The method according to any one of claims 2 to 4, wherein displaying on the display includes overlapping and displaying the second model and the flight path on the display. The step of generating the second model comprises
Generating a buffer model including height correction information for each of a plurality of areas into which a predetermined shape is divided based on the predetermined distance;
6. The method according to any one of the preceding claims, comprising generating the second model based on the first model and a buffer model. Generating the second model based on the first model and the buffer model corresponds to height information of each of a plurality of regions corresponding to the predetermined shape based on the predetermined region of the second model. Setting the height information as a sum of the height correction information defined in the buffer model and the height information of the area corresponding to the predetermined area of the first model;
In setting the height information of each of the plurality of regions corresponding to the predetermined shape based on the predetermined region of the second model, the height information is already set in any of the plurality of regions. If the height information corresponding to the addition result in the area is higher than the height information already set, the height information corresponding to the addition result is set as the height information in the area The method of claim 6, comprising: Generating the second model based on the first model and the buffer model is:
Adding corresponding height correction information of the buffer model to height information defined in each of the plurality of areas corresponding to the predetermined shape with reference to the predetermined area of the first model;
Setting the height of the predetermined area in the second model as the highest height information among the height information of each of the plurality of areas corresponding to the predetermined shape after the addition. Method described.   The method according to any one of claims 6 to 8, wherein the buffer model includes a hemispherical model whose radius is the input distance and a rectangular parallelepiped model whose height is the input distance.   The method may further include the step of correcting the flight path based on the second model when it is determined that the distance between the input flight path and the feature is less than the input distance. The method according to any one of to 9. A program executed by a computer to determine the safety of the flight path of an aircraft,
The program is stored in the computer
Reading from a storage device of the computer a first model including height information of features of each of a plurality of areas dividing a predetermined area;
Expanding the feature height information of each of the regions defined in the first model based on a predetermined distance to generate a second model;
Accepting an input of a flight path of the aircraft scheduled in the predetermined area;
Comparing the second model with the flight path to determine whether the distance between the flight path and the feature is less than the predetermined distance;
Outputting the determination result.