JP2818992B2 - Terrain information analysis device and terrain information analysis method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terrain information analysis device and a terrain information analysis method, and more particularly, to a method for forming a detailed analysis diagram of a necessary and sufficient area based on contour line information and ancillary information of a wide area. It relates to a means to quickly create and display.

[0002]

2. Description of the Related Art In a conventional terrain information analysis method, for example, a normalized mesh is created for an analysis target area, and elevation values at all intersections of the mesh, that is, all grid points are obtained from contour line information and stored in advance.
When display is actually required, the topography is analyzed based on the stored elevation values of each grid point in order to obtain a sectional view between two designated points and to display the three-dimensional shape of the designated area. Was.

In order to improve the accuracy of this analysis method, it is necessary to subdivide the mesh and increase the number of grid points.
As described above, the amount of calculation increases as the mesh is subdivided, and the memory for storing analysis results and the like also has a disadvantage of having a large capacity.

In addition, there is a problem that the analysis accuracy is the same in a short distance region and a long distance region from an analysis target point, and extra calculations are performed at a long distance point where not so detailed display is required.

On the other hand, Japanese Patent Application Laid-Open No. 61-148576 discloses a method of three-dimensionally displaying the shape and the like of the ground surface based on high-density pixel information such as high-altitude photographed image data. Specifically, when forming a ground surface approximated by a triangle from high-density pixel information, if the pixel information exists in a plurality of approximated triangles, high-speed display is realized by thinning out display target pixels. doing. However, this is not a method of three-dimensionally displaying the shape and the like of the ground surface based on vector information.

[0006] Japanese Patent Application Laid-Open No. 61-267778 proposes a method for displaying a detailed map near the current position and a coarse map for the rest in an on-vehicle map display device.

Further, Japanese Patent Application Laid-Open No. 2-61690 discloses that
On the in-vehicle map display device, the area near the current point is
We have proposed a method of connecting a small scale at a distance and a medium scale at the middle.

Japanese Unexamined Patent Publication No. 1-106270 proposes a system in which a perspective view is created in consideration of the influence of the terrain, and whether or not a view can be seen is displayed on a map.

[0009]

In the above-described normalized mesh method, since the analysis accuracy in the analysis target area is uniform,
Analysis with high accuracy requires a large amount of calculation and takes time, and the memory for storing analysis results and the like has a large capacity.

The system disclosed in Japanese Patent Application Laid-Open No. 61-148576 proposes a thinning method based on bitmap information, and cannot be easily applied to terrain analysis based on vector information.

In the method disclosed in Japanese Patent Application Laid-Open No. 61-267778, a detailed map display range is set irrespective of parameters such as the speed of a car or a helicopter using the analyzed terrain information. However, there is a problem that the unnecessary display area behind the already passed is increased.

In the system disclosed in Japanese Patent Application Laid-Open No. 2-61690,
The unnaturalness of the display of the connection zone connecting the middles at the medium scale is noticeable, and in some cases, the conventional method in which some scales are switched is better in visibility.

In the method disclosed in Japanese Patent Application Laid-Open No. 1-106270, an operation is performed with the same accuracy as that of a visible area even in an invisible area, which is wasteful.

An object of the present invention is to optimize the number of grid points, reduce unnecessary computations as much as possible, and reduce the amount of calculations.
It is an object of the present invention to provide a terrain information analysis device and a terrain information analysis method provided with means for shortening the analysis time and reducing the memory capacity for storing analysis results and the like.

[0015]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides means for detecting an attribute such as a traveling direction speed of an object such as an automobile using the analyzed terrain information; proceedable direction, the distance from the analysis point, near the analysis point on the basis of various attributes such as the analysis target area is densely analysis from the analysis point where physical attributes and object in accordance with the analysis object such as a process velocity there was Means for sparsely setting a point to be analyzed as the distance from the point, means for analyzing map information consisting of vector data at the set point to be analyzed, and elevation by combining the analysis result and terrain information
A terrain information analysis device comprising means for calculating and displaying value information and the like is proposed.

The analysis target point setting means includes means for excluding an analysis target point existing in a portion which becomes a shadow of the terrain among the analysis target points which have been temporarily set in consideration of a direction and a distance from the analysis point; It can include a means for displaying the portion to identifiably the display means and other portions
You.

In order to achieve the above object, the present invention also includes a step of detecting an attribute such as a traveling direction speed of an object such as an automobile using the analyzed terrain information; in the traveling direction speed of the object ranges to be analyzed
Calculating according to an attribute such as degree, and determining an analysis target point by setting grid points from dense to coarse according to the distance and / or speed from the point where the object is present in the analysis target range; Reading terrain information;
The present invention proposes a terrain information analysis method including a step of calculating and storing elevation value information and the like when the reading of terrain information is completed, and a step of displaying the calculated data of the analysis target point .
You.

When the data of the terrain information is managed in a plurality of areas, the step of reading the terrain information includes the step of determining whether or not each grid point is in the same area, and the step of reading the data of the terrain information. Is included in a plurality of areas, a step of searching the plurality of areas and reading out information is included.

[0019]

According to the present invention, such as an automobile that requires a terrain analysis in forming the current position or the grid from the analysis point, objects and eg automobiles or helicopter for mounting using this topographic information analyzer for analysis Depending on the speed and altitude and the attributes of the topography of the analysis target area, the grid points, that is, the density of the analysis target point, are changed according to the distance from the analysis point and the angle from the traveling direction, etc., and the arrangement of the analysis target point is appropriate While sufficient terrain analysis accuracy can be ensured for the necessary directions and distance ranges, the number of analysis target points decreases as the distance increases, so that the total calculation amount can be reduced. Therefore, within the required range, highly accurate elevation value information can be obtained in a short time, the number of the entire analysis target points is optimized, the calculation amount is reduced, and comfortable real-time display is realized.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a terrain information analysis method and a terrain information analysis device according to the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing a configuration of an embodiment of a terrain information analysis device according to the present invention. The terrain information analysis device includes a sensor information processing unit 101 for analyzing information such as the speed, altitude, and current position of a flying object such as a helicopter, which is captured from a sensor 108 (not shown). Terrain information input means 102 for fetching terrain information from an external storage device or the like for storing terrain information
A storage unit 103 for storing processing target terrain information and the like fetched corresponding to the area designated by the input / output unit 106; and an analysis result display unit 1 based on the stored terrain information.
A terrain information display means 104 for converting the information to the information suitable for the display function of 05, an analysis result display means 105 comprising a CRT or the like for displaying an analysis result, and a processing instruction comprising a keyboard, a mouse, a trackball, etc., are inputted. It comprises an input / output means 106 and a terrain analysis means 107 for analyzing and processing terrain information to be processed in accordance with an instruction from the input / output means 106. Since the input / output unit 106 may be realized in a form such as a so-called touch panel on the screen of the analysis result display unit 105, the input / output unit 106 may have not only an input function but also a display / output function. 1
05 and the input / output means 106 are not so strict.

Among them, the terrain analysis means 107 fetches the analysis information from the sensor information processing means 101 to determine the range and quantity of the analysis target point.
1, an analysis area calculation unit 112 for calculating an area to be analyzed among the displayed topographic areas, a topographic information selection unit 113 for selecting topographic information in the analysis target area of the displayed topographic information, An analysis unit 114 that calculates information to be analyzed and a result information editing unit 115 that edits information of an analysis result are included.

The terrain analysis means 107 fetches necessary information from the terrain information input means 102 and develops it in the storage means 103. On the other hand, the analysis result display means 105 also has a function of displaying the information selected by the terrain information selection means 113 in real time.

FIG. 2 is a block diagram showing an example of a system configuration for realizing the terrain information analyzing apparatus of the embodiment of FIG. 1 as a computer system. The terrain information analysis device includes a central processing unit (CPU) 100 and a main memory 200.
, A disk device 103 and a display device 105 such as a CRT.
, Keyboard 106, mouse 106, sensor 10
8 is provided.

The main memory 200 is a central processing unit (CPU)
100 operation programs are stored, and terrain information to be processed is also stored. The central processing unit 100 executes a program stored in the main memory 200 to realize various functions of the terrain information processing device. The disk device 103 is an external storage device that hierarchically stores various terrain information, such as contour lines and roads, and also stores a large amount of information configured for a plurality of scales. The sensor 108 is mounted on a helicopter, a vehicle, or the like on which the terrain information analysis device is mounted or uses the information through a communication line, and is a means for obtaining motion information such as altitude, traveling direction, speed, and position.

FIG. 3 and FIG. 4 are views for explaining an example of a management method of the terrain information. In this embodiment, the entire topographical information is divided into a plurality of substantially equal sections and managed. The hatched area of the section shown on the map in the upper part of FIG. 3 is further divided and stored into, for example, nine areas having substantially the same area as in the lower part of FIG.

As shown in FIG. 4, the terrain information Ni of each area is managed as a pair with index information I for searching the area. The terrain information Ni includes terrain information N1 to Nn of a plurality of scales (for example, 1/20000, 1/50000,...) For the same area, and corresponding index information I1 to In.
have. The terrain information Ni of a certain scale is managed by being divided into area units, that is, areas 1 to k, defined for each scale. The index information Ii is the XY of the position information of the lower left corner.
The coordinates include a relative distance from the X coordinate, a relative distance from the Y coordinate, and a pointer indicating a storage address of an area of the terrain information corresponding to the area. The XY coordinates of the position information are represented by absolute coordinates and are continuous with the terrain information of different areas. With this management method, index information is searched for the designated scale and area, the topographical information of the corresponding area is read out, expanded in the main memory 200, and sent to the topographical information display means 104. Will be displayed.

FIG. 5 is a diagram for explaining an example of the hierarchical structure of the terrain information in units of areas and the structure of contour line information which is a part thereof. The terrain information of the area R includes header information and a plurality of types of information (topographic map elements:
Water system information, road information, contour line information, etc.). The header information includes lower left corner coordinates (XL, YL), upper right corner coordinates (XU, YU) indicating the area of the terrain information of the area, and type information 1
, And a type information index indicating the storage address of .about.k. The content of each type information is, for example, in the case of contour line information,
The number of contour lines and line information 1 to m. Each line information is composed of the number of constituent points P, attached information D (altitude value in the case of a contour line), and each constituent point.

FIG. 6 is a flowchart showing an example of the basic procedure of the analysis processing of the present invention. In this example, when a flying object such as a helicopter flies at a low altitude on the ground, an analysis of an obstacle is performed in order to display collision prevention guidance in the aircraft.

The terrain analysis means 107 starts a terrain analysis routine shown in FIG. 6 based on, for example, an obstacle display command from the keyboard 106 and executes the following processing. Step 601: A region to be analyzed, that is, a range, among the displayed topographic regions is calculated. Step 602: The analysis target point is determined as a grid point in the analysis target range. Step 603: When the terrain information data is managed in a plurality of areas, it is determined whether or not each grid point is in the same area. Step 604: If included in a plurality of areas, search in the plurality of areas and read information. Step 605: When the analysis target point is in the same area, or when the analysis target point is in a plurality of areas and the reading of the information from the plurality of areas is completed, for example, the elevation value information is calculated and the present apparatus is calculated. If the purpose of use is to prevent flying objects from collision, select the highest elevation in each area,
Remember. Step 606: It is determined whether or not the information calculation of the entire range has been completed.
If completed, the process proceeds to the display data conversion process. Step 607: Convert the calculated data of the analysis target point into displayable data. Step 608: Display on a display device such as a CRT.

FIG. 7 is a view for explaining an example of a main menu screen for inputting an analysis point. In this example, the sensor information processing unit 101 sends the sensor information to an arbitrary scale, for example, 1/50000 terrain information displayed on the main menu of the display device 105 via the terrain information display unit 104.
For example, information such as the traveling direction, speed, and altitude of the helicopter is fetched from 8, and the traveling direction and speed are displayed on the same screen in the form of a vector.

FIG. 8 is a diagram for explaining an example of a factor for limiting the analysis target range when calculating the analysis target range in the displayed terrain region in step 601.
Here, in order to determine a range to be analyzed, an analysis point (in this case, the current position of the helicopter) S, an effective distance D from the analysis point, and an effective turning angle θ are used as key information with speed information obtained from the sensor 108 as key information. Set.

FIG. 9 is a view for explaining an example of a method of managing information on the effective turning angle of the helicopter. As the speed information, a value that is graded stepwise at a fixed rate is used.
The turnable angle is determined accordingly. For example, when hovering, i.e., hovering in the air and stopping, 36
Although it is possible to turn 0 °, the angle at which it can be turned is limited as the speed increases. Conversely, when the speed is low, the effective distance of the range to be analyzed may be short, but as the speed increases, the distance must be analyzed.

FIG. 10 is a diagram for explaining an example in which the analysis target range changes according to the speed level. FIG. 10A shows a case where the speed level is 2, and FIG. 10B shows a case where the speed level is 8. d1 and d2 are effective distances.
Note that if FIG. 10A is made the same scale as FIG. 10B, it becomes too small to draw, so it is relatively enlarged here.

FIG. 11 is a diagram for explaining an example of a procedure for obtaining coordinates of a point to be analyzed. In step 602 of FIG. 6, the line segments SB, SC, SD, SE, SF, SG, SH, and the line segment SA indicating the traveling direction from the analysis point S are centered.
Create SI, SJ, SK. At this time, the line segments SA and SB
Is made smaller, and the angle is made larger toward the SF side. The line segments SB and SG are symmetric about the line segment SA. The other line segments are similarly determined. Next, the distances R1 to R6 from the point S are determined so that the distance near the point S is short and the distance far from the point S is long. With this method, a sector having a center S, radii R1 to R6, and line segments SA to SK is formed. The coordinates are obtained by using the intersection, ie, the grid point, formed in the sector as the analysis target point.

FIG. 12 is a diagram for explaining another example of the procedure for obtaining the coordinates of the analysis target point. Here, the analysis point S
A coordinate system using a point as the center coordinates (X0, Y0) is used. (1) Analysis target points P1, P7, P13, P19, P25
Are obtained as follows. Coordinates of point P1 = (X0 + R1, Y0) coordinates of point P25 = (X0 + R5, Y0) (2) When the general angle θ represented by the radial radius SX is in the first quadrant, the coordinates are obtained as follows. Can be Coordinate of point Pn1 = (X0 + Rncosθn, Y0 + Rnsinθn) Rn = distance from analysis target point R1 to R5 θn = angle formed by radial radius SX and X coordinate (3) When general angle θ represented by radial radius SX is in the second quadrant , The coordinates are obtained as follows. The coordinates of the point Pn2 = (X0−Rncos (180 ° −θn), Y0 + Rnsin (180 ° −θn)) (4) If the general angle θ represented by the radial radius SX is in the third quadrant, the coordinates are as follows: Desired. The coordinates of the point Pn3 = (X0−Rncos (θn−180 °), Y0−Rnsin (θn−180 °)) (5) If the general angle θ represented by the radial radius SX is in the fourth quadrant, The coordinates are determined. Coordinates of the point Pn4 = (X0 + Rncos (360 ° −θn), Y0−Rnsin (360 ° −θn)) Even in this case, in step 602, the coordinates of the analysis target point centering on the analysis point are determined in all directions. Desired.

Next, in step 603, it is first determined whether or not the coordinates of the four corners obtained in step 602 are present in, for example, the area 5 shown in FIG.

If it exists in area 5, step 6
At 05, the information on the contour lines included in the area 5 is read onto the main memory 200. The information of the contour line is searched for the calculated blocks at the four corners at the analysis target points, and the elevation value of the block is obtained.

FIG. 13 is a view for explaining contour line information of the analysis target area. FIG. 14 is a diagram illustrating an example of a procedure for enlarging a hatched portion in FIG. 13 and obtaining an intersection between the contour line information and the block in one block in the analysis target area.

As shown in FIG. 14, the contour line information of the elevation value 200 m in the block 3 is composed of the constituent points (Xa1, Ya1) to (Xa3, Ya3) and (Xd1, Yd) representing the position information of the contour line.
1) and (Xd2, Yd2). Based on the coordinates of the constituent points and the coordinates of the four corners, it is determined whether there is an intersection existing in the block 3. When there is only one contour line information, the elevation value of the contour line information is stored in the memory as the elevation value in the block 3.

As shown in FIG. 14, when there are two or more pieces of contour information, the highest elevation value is stored as the elevation value of the area.

On the other hand, when there is no contour information as in the block 20 in FIG. 13, for example, the average value of the elevation values of the upper, lower, left and right blocks is stored in the memory as the elevation value of the corresponding area. In the case of the block 20 in FIG. 13, the length is 160 m.

Step 605 for all fan-shaped blocks
In step 606, it is determined whether the calculation of the information of the entire range is completed. As a result, the coordinates, elevation value, and block number of the upper left corner of each block are stored as information of the block.

FIG. 15 is an explanatory diagram when the analysis target point extends over a plurality of areas, that is, when it is determined in step 603 that the analysis target point extends over, for example, the areas 5, 6, 8, and 9 in FIG. is there. In step 604, when the analysis target point M11 is included in the area 8, the contour line information included in the ranges M3, M6, M11, and M5 is read into the memory. Similarly, in the case of area 9,
The contour line information in the range M3, M8, M9, M4 is read, and in the case of the area 6, the range M3, M2, M10, M7
Read the contour information in the memory.

Thereafter, the processing of step 605 is executed for each area based on the read contour line information.

FIG. 16 is a diagram showing a display example of the result of the obstacle analysis processing. Based on the altitude value information obtained in step 606, in step 607, display data is converted so as to display an obstacle in the traveling direction. In step 608, the information is displayed on the display device 105 such as a CRT.

Actually, for example, the analysis point indicating the current position and the analysis target area are displayed in a superimposed manner on the same screen displaying the terrain information. Thereafter, the current altitude acquired from the sensor 108 is compared with the altitude value obtained in step 606, and a portion of the block having an altitude value equal to or higher than the current altitude is painted with, for example, an emphasis color to call the pilot's attention. If there is a portion higher than the current altitude in the traveling direction, an alarm can be sounded and an alarm can be issued to the operator.

FIG. 17 is a diagram showing a display example of the result of the obstacle analysis processing of the directional antenna. The direction and effective range of an antenna having directivity are determined by the performance of the antenna. Create limited analysis target points within the effective range,
Analyze and display.

FIG. 18 is a diagram showing a display example of the result of the analysis processing along the line segment to be analyzed. When the analysis target line segment is road information, when a moving object such as a car moves along a predetermined route, for example, a height difference of a road from a current point to a destination point taken from a sensor at the request of an operator is displayed. . When there is a route change, the new route is stored in accordance with the route change instruction from the operator, and is displayed in the same manner.

FIG. 19 is a diagram showing a display example of the result of the analysis processing for the human visual field and a procedure for excluding the invisible part. Considering human vision and visual field,
High-precision information is required for short distances, but not so accurate information for long distances. In addition, if the visual field is within an angle of about 120 ° left and right from the center, it is considered appropriate as information. In the case of analysis, particularly, an analysis target point in a place where it cannot be seen is excluded from processing targets, and the overall processing is speeded up. In the example of FIG. 19, a hatched portion is a portion not to be processed.

FIG. 20 is a diagram for explaining a procedure for converting display data for analysis processing in consideration of human visual acuity and visual field. A procedure for converting the altitude value information obtained from the analysis result into the display information will be described.

The distance between the two points A and B is determined and is set as H1. Similarly, H2 to H4 are obtained. The sum of H1 to H4 is defined as H14, and the effective viewing angle of human being 120 degrees and H14 are set to the same value in relative ratio. For the point B, the value of the horizontal axis to be displayed is obtained from the following proportional expression. Assuming that the value to be obtained is X, 120: H14 = X: H1, and X = (H1
× 120) / H14 Similarly, for the point C, the following relationship is obtained. X = ((H1 + H2) × 120) / H14 Hereinafter, similarly, the distance obtained from the coordinate value of each block is converted into display data.

As shown in FIG. 20, the horizontal axis in the center is set to 0 degree, and the effective viewing angle is set symmetrically . The vertical axis is the altitude value
(Or altitude) and plot the converted values.
The elevation value of each point on the line segment SA is plotted on a 0 degree line. Thereafter, points at the same distance from the point S are connected by a line segment and displayed on the screen as shown in FIG.

[0053]

According to the present invention, the analysis target point in the analysis processing range of the terrain information can be appropriately selected according to the processing purpose, so that while ensuring sufficient terrain analysis accuracy,
The amount of calculation can be reduced, and effective information can be provided to the user in real time.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a terrain information analysis device according to the present invention.

FIG. 2 is a block diagram showing an example of a system configuration for realizing the terrain information analyzing apparatus of the embodiment of FIG. 1 as a computer system.

FIG. 3 is a diagram illustrating an example of a basic configuration of terrain information.

FIG. 4 is a diagram illustrating an example of a management method of terrain information.

FIG. 5 is a diagram illustrating an example of a hierarchical configuration of topographic information in area units and a configuration of contour line information which is a part thereof.

FIG. 6 is a flowchart illustrating an example of a basic procedure of an analysis process according to the present invention.

FIG. 7 is a diagram illustrating an example of a main menu screen for inputting an analysis point.

FIG. 8 is a diagram illustrating an example of an analysis target range limiting factor.

FIG. 9 is a diagram illustrating an example of a management method of information on an effective turning angle of a helicopter.

FIG. 10 is a diagram illustrating an example in which an analysis target range changes according to a speed level.

FIG. 11 is a diagram illustrating an example of a procedure for obtaining coordinates of an analysis target point.

FIG. 12 is a diagram illustrating another example of the procedure for obtaining the coordinates of the analysis target point.

FIG. 13 is a diagram illustrating contour line information of an analysis target area.

FIG. 14 is a diagram illustrating an example of a procedure for obtaining an intersection between a contour line information and a block in one block in an analysis target area.

FIG. 15 is an explanatory diagram when a block in an analysis target area extends over a plurality of areas;

FIG. 16 is a diagram illustrating a display example of a result of the obstacle analysis processing.

FIG. 17 is a diagram illustrating a display example of a result of the obstacle analysis processing of the directional antenna.

FIG. 18 is a diagram illustrating a display example of a result of an analysis process along an analysis target line segment.

FIG. 19 is a diagram illustrating a display example of a result of an analysis process for a human visual field and a process exclusion procedure for an invisible portion.

FIG. 20 is a diagram illustrating a procedure for converting display data of analysis processing for a human visual field.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 Central processing unit (CPU) 101 Sensor information processing means 102 Terrain information input means 103 External memory (disk device) 104 Terrain information display means 105 Analysis result display means (display device) 106 Input / output means (keyboard, mouse, etc.) 107 Terrain Analysis means 108 Sensor 111 Analysis factor selection means 112 Analysis area calculation means 113 Terrain information selection means 114 Analysis means 115 Result information editing means 200 Main memory 601 Analysis range determination processing 602 Analysis target point determination processing 603 Analysis target point area determination processing 604 Multiple Area search and information readout processing 605 Elevation value information calculation and storage 606 Judgment completion of all range information calculation 607 Conversion processing to display data 608 Display processing

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-219084 (JP, A) JP-A-3-229288 (JP, A) JP-A-63-73111 (JP, A) JP-A-61- 26778 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G09B 29/10 G01C 21/00 G08G 1/0969

Claims (4)

(57) [Claims] A means for detecting an attribute such as a traveling direction speed of an object such as an automobile using the analyzed terrain information, a physical attribute such as a detected traveling speed of the object and analysis. Based on the direction in which the object can proceed from the analysis point where the object exists, the distance from the analysis point, and various attributes of the analysis target area, the vicinity of the analysis point is sparser as the distance from the analysis point increases. Means for setting map information; means for analyzing map information consisting of vector data at the set analysis target points; and calculating elevation value information and the like in combination with the analysis results and topographic information.
And a means for displaying information. 2. The terrain information analysis device according to claim 1, wherein the analysis target point setting means sets the front terrain among the analysis target points which are temporarily set in consideration of a direction and a distance from the analysis point. A terrain information analysis device, comprising: means for excluding an analysis target point existing in a shadow portion; and means for displaying the excluded portion on the display means so as to be distinguishable from other portions. Detecting an attribute such as a traveling direction speed of an object such as an automobile using the analyzed terrain information; and determining a range to be analyzed in the displayed terrain region in the traveling direction of the object. Calculating in accordance with an attribute such as speed; and determining a point to be analyzed by setting grid points from dense to coarse according to the distance from the point where the object is present in the analysis target range and / or the speed or the like. Reading the topographical information; calculating and storing altitude information and the like when the reading of the topographical information is completed; and displaying the calculated data of the analysis target point. analysis method. 4. The terrain information analysis method according to claim 3, wherein the step of reading the terrain information includes: when the data of the terrain information is managed in a plurality of areas, the grid points are in the same area. Determining whether or not the area is within the area, and, when the data of the terrain information is included in a plurality of areas, searching the area and reading the information. Information analysis method.