JPH11287665A - Altitude calculating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an altitude calculating device of an on-vehicle navigation system enabling to accurately acquire the altitude of the current vehicle position. SOLUTION: An altitude calculating device uses a computing means 14 to calculate the altitude of the current vehicle position from map information stored in a map information storage means 11 and the current vehicle position obtained from a vehicle position detection means 13. A control means 16 displays the altitude on a display means 17 and outputs the voiced altitude to a voice output means 18, whereby the user can acquire the altitude value of the current vehicle position. The map displayed on the display means 17 is generated by a map generation means 12 from the map information stored in the map information storage means 11. Instructions from the user are given by a control means 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an altitude calculating apparatus mounted on a vehicle such as an automobile and calculating an altitude.

[0002]

2. Description of the Related Art Heretofore, it has been mounted on vehicles such as automobiles,
Global Positioning System
2. Description of the Related Art An in-vehicle navigation device that presents a user with a three-dimensional position of a vehicle using a three-dimensional position measuring device called (GPS) is known.

However, if the vehicle moves to a place where the radio waves of the four positioning satellites cannot be received, it becomes impossible to measure the altitude value. In addition, since the arrangement of the positioning satellites in which the two-dimensional position of the vehicle is obtained with high accuracy is different from the arrangement of the positioning satellites in which the altitude value is obtained with high accuracy, the altitude value of the vehicle obtained by GPS has an error Was big.

[0004]

As described above, the conventional on-vehicle navigation device for obtaining the altitude value of the current position of the vehicle using only GPS has a problem that the error of the altitude value is large.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and uses a map data stored in a map information storage means to accurately determine an elevation value of a current vehicle position. It is an object of the present invention to obtain an altitude value calculating device for calculation.

It is another object of the present invention to provide an altitude calculating apparatus which allows a user to easily recognize the altitude of the current vehicle position.

[0007]

According to the present invention, there is provided an altitude information calculating apparatus comprising: a map information storing means for storing altitude information corresponding to an area or a point; a vehicle position detecting means for detecting a current vehicle position; Means for calculating an altitude value at a current vehicle position based on the position of the area or point, the current vehicle position, and altitude information of the area or point.

[0008] Further, map information storage means for storing altitude information corresponding to the area, vehicle position detection means for detecting the current vehicle position, and selecting an area near the area including the current vehicle position. Means for calculating an altitude value at the current vehicle position based on the position of the area including the current vehicle position, the current vehicle position, and the altitude information of the selected area. is there.

Further, map information storage means for storing altitude information corresponding to a point, vehicle position detection means for detecting a current vehicle position, and two points close to the current vehicle position are selected. Means for calculating an altitude value at the current vehicle position based on the selected two positions, the current vehicle position, and the altitude information of the selected two points.

[0010]

According to the present invention, there is provided an altitude information calculating apparatus comprising: map information storing means for storing altitude information corresponding to an area or a point; vehicle position detecting means for detecting a current vehicle position;
Means for calculating an altitude value at a current vehicle position based on the position of the region or point, the current vehicle position and altitude information of the region or point,
By using the position of the area or point where the altitude information is stored in the map information storage means and the current vehicle position, even when the area or point where the altitude information is stored and the current vehicle position are different. The altitude value at the current position of the vehicle can be calculated.

Further, map information storage means for storing elevation information corresponding to the area, vehicle position detection means for detecting the current vehicle position, and selecting an area near the area including the current vehicle position. Means for calculating an altitude value at the current vehicle position based on the position of the area including the current vehicle position, the current vehicle position and the altitude information of the selected area, By using the position of the area where the elevation information is stored in the map information storage means and the current vehicle position, the current vehicle position is determined based on the positional relationship between the position of the area where the elevation information is stored and the current vehicle position. The altitude value at the position is calculated.

Further, map information storage means for storing altitude information corresponding to a point, vehicle position detection means for detecting a current vehicle position, and two points close to the current vehicle position are selected. Means for calculating an altitude value at the current vehicle position based on the determined two positions, the current vehicle position, and the altitude information of the selected two points, the map information storage means By using the position of the point where the altitude information is stored and the current vehicle position, the altitude value at the current position of the vehicle can be obtained even when the point where the altitude information is stored and the current vehicle position are different. It can be calculated.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a block diagram showing an on-vehicle navigation device including an altitude information calculation device according to Embodiment 1 of the present invention. In FIG. 1, reference numeral 11 denotes a map information storage unit that stores map information including road information, background information, altitude information, and the like. 12 extracts map information in a predetermined area from the map information included in the map information storage unit 11. Map generating means for generating a map composed of roads, backgrounds and the like; 13, a vehicle position detecting means for detecting the current vehicle position by various sensors; 14, map information and vehicle position detecting means included in the map information storage means 11 A calculating means for calculating the altitude value of the current vehicle position from the vehicle position information obtained from 13; an operating means 15 for inputting an instruction from a user; 16 controlling information to be output to generate a video signal and an audio signal The control means 17 is a display means for displaying a map and an altitude value according to the video signal from the control means 16, and the reference numeral 18 is an audio signal from the control means 16. Therefore it is an audio output means for outputting altitude values and the like.

FIG. 2 shows an example of the configuration of a vehicle-mounted navigation device according to the first embodiment of the present invention. In FIG. 2, reference numeral 21 denotes a control unit for performing various calculations and control of the entire apparatus, and reference numeral 22 denotes a CD in which map information is stored.
A ROM and CD-ROM driver, 23 a GPS receiver for measuring the current vehicle position, 24 an input panel for inputting instructions given by the user to the device, and 25 a liquid crystal display for displaying an image sent from the control unit, Reference numeral 26 denotes a speaker that outputs a sound sent from the control unit. Control unit 21
Are a CPU 21A, a ROM 21B storing a program and information essential to the operation of the program, a CPU 21A,
RAM 21C used when the arithmetic unit 21A performs an operation, I / O2 for inputting / outputting between the control unit 21 and the outside
1D and a control unit 21E that generates signals to be sent to the liquid crystal display 25 and the speaker 26.

FIG. 3 shows an example of a storage form of the altitude information in the map storage means 11. FIG. 3A shows an expression form of the altitude information. The map information is stored in units called meshes separated by straight lines parallel to the parallels and meridians. In addition, each mesh
And n in the meridian direction, a total of m × n small areas. Then, the i-th subregion R in the meridian direction and the j-th meridian direction
Let altitude information of i, j be h (Ri, j).

FIG. 3B shows a storage form of the altitude information in the map information storage means 11. h (Ri,
j) are arranged in ascending order in the latitudinal direction i, and those having the same i are arranged in ascending order in the meridian direction j.

FIG. 4 shows another example of a storage form of the altitude information in the map storage means 11. FIG. 4A shows an expression form of the altitude information. For the roads included in each mesh, the intersections n0 to n4 and the dead end point n4
Are called nodes, and the roads l0 to l5 are called links. The start point and end point of each link are always any node.
Further, points s0 to s2 provided for convenience to express the shape and attributes of the road are referred to as interpolation points.

FIG. 4B shows a storage form of the altitude information in the map information storage means 11. The link information includes link information 41, component information 42, and structure information 43. The link information 41 includes a link number uniquely assigned to the link, a road type indicating a type of road such as a national road and a prefectural road, a road number indicating a road line number of the road,
Component information indicating the width, the number of lanes, traffic regulations such as one-way traffic, the number of components indicating the total number of nodes forming the link and the number of interpolation points for expressing the shape of the link, and component information indicating the address of the component information 42 A pointer, a structure number indicating the number of structures such as a tunnel or a bridge when the link exists, and a structure information pointer indicating an address of the structure information 43.

The component information 42 includes the XY of the starting point of the link.
It is composed of each Z coordinate, each XYZ coordinate of the interpolation point, and each XYZ coordinate of the end point of the link.

The structure information 43 indicates a structure type indicating the type of the structure, and the number of the node or interpolation point where the section in which the structure exists starts from the start point of the link and ends with the number of the node or interpolation point. It consists of a start point number and an end point number.

FIG. 5A shows a display example on the display means 17 according to the first embodiment of the present invention. On screen 51,
The altitude value of the current vehicle position is displayed as a numerical value 52.

FIG. 5B shows a display example on the display means 17 according to another embodiment of the present invention. On the screen 53, the altitude value of the current vehicle position is displayed as a bar graph-shaped figure 54. The upper end of the graphic 54 represents the altitude value of the current vehicle position.

Next, the operation will be described with reference to the flowcharts of FIGS. FIG. 6 is a flowchart showing the operation of the vehicle-mounted navigation device according to the present invention. In step 61, the vehicle position detecting means 13
In, the current vehicle position is specified. In step 62, the arithmetic means 14 calculates the elevation value of the current vehicle position from the map information extracted from the map information storage means 11 and the current vehicle position specified in step 61. In step 63, the control means 16 generates a video signal as shown in FIG. 5A or FIG. 5B from the elevation value of the current vehicle position calculated in step 62,
Output to display means 17. The display means 17 displays this on a screen. In step 64, it is determined whether or not to end the operation of the present apparatus. If the end of the operation is instructed by the user through the operation means 15, the operation ends. Otherwise, the process returns to step 61.

FIG. 7 is a flowchart showing the operation for calculating the altitude value of the current vehicle position. In step 71, the elevation information of the mesh including the current vehicle position and the eight neighboring meshes is extracted from the map information storage unit 11. In step 72, several pieces near the current vehicle position are selected from the altitude information extracted in step 71. In step 73, the altitude value of the current vehicle position is calculated from the altitude information selected in step 72.

FIG. 8 shows an example of the calculation of the altitude value when the altitude information is expressed and stored in the map storage means 11 in the form as shown in FIG. The altitude information of the small area Ri, j including the current vehicle position C and three small areas in the vicinity thereof is selected. At this time, the method of selecting the three nearby small areas is such that the center point of Ri, j is ri, j and the current vehicle position C
Is at the lower left when viewed from ri, j, Ri-1, j-
1, Ri, j-1, Ri-1, j, R at lower right
i, j−1, Ri + 1, j−1, Ri + 1, j, and at the upper left, Ri−1, j, Ri−1, j + 1, Ri, j
+1; when it is on the upper right, Ri + 1, j, Ri, j + 1,
Ri + 1 and j + 1.

For example, as shown in FIG. 8, the length of the small area around the current vehicle position C in the meridian direction is X, the length in the latitude line is Y, and the current vehicle position C is viewed from ri, j. In the meridian direction x (> 0) and the latitude line direction y (> 0) at the upper right. At this time, the altitude value H at the current vehicle position is calculated as follows.

[0027]

(Equation 1)

FIG. 9 shows an example of calculating an altitude value when the altitude information is represented and stored in the map storage means 11 in a form as shown in FIG. In the vehicle position detecting means 13, the link li which is assumed to be currently driving the vehicle
To identify. Then, two interpolation points sj and sj + 1 closest to the current vehicle position C are selected, and elevation values zj and zj + 1 at these points are extracted. At this time, sj and sj
Assuming that the distance of +1 is D and the distance between C and sj is d, the altitude H at the current vehicle position C is calculated as follows. H = (dzj + (D−d) zj + 1) / D

Embodiment 2 When displaying the altitude value of the current vehicle position on the display means 17, it may be difficult for the user to recognize the value at a glance while driving the vehicle. Therefore, it is conceivable to change the display color according to the altitude value.

FIG. 10 shows a display example on the display means 17 according to the second embodiment of the present invention. On the screen 101, the elevation value of the current vehicle position is displayed as a bar-graph-like figure 102,
03 and 104, which are represented in different colors. The upper end of the figure 104 represents the altitude value of the current vehicle position.

Next, the operation will be described with reference to the flowcharts of FIGS. FIG. 11 is a flowchart showing the operation of the vehicle-mounted navigation device according to the present invention. In step 111, an altitude value-display color correspondence table for determining a display color corresponding to the altitude value is created. In step 61, the vehicle position detecting means 13 specifies the current vehicle position. In step 62, the arithmetic means 14 calculates the elevation value of the current vehicle position from the map information extracted from the map information storage means 11 and the current vehicle position specified in step 61. In step 112, the control means 16 executes step 62
The video signal as shown in FIG. The display means 17 displays this on a screen. In step 64, it is determined whether or not to end the operation of the present apparatus. If the end of the operation is instructed by the user through the operation means 15, the operation ends. Otherwise, the process returns to step 61.

FIG. 12 is an example of an altitude-display color correspondence table. Elevation value H is H0 or less, H0 to H1, H1 to H
,..., Hn−1 or more, the code numbers CC of the display colors are designated as CC0, CC1, CC2,.
Cn.

FIG. 13 is a flowchart showing the operation of displaying the altitude value of the current vehicle position. Step 131
Then, the magnitudes of H and H0 are compared. If H is larger than H0, the process proceeds to step 132a. Otherwise, in step 132b, a bar graph-like graphic corresponding to 0 to H is generated with a display color of code number CC0 and output to the display means 17. The display means 17 displays this on the screen. Then, the operation ends. In step 132a, 0
From the bar graph to the code number C
It is generated with a display color of C0 and output to the display means 17.
The display means 17 outputs this to the screen.

In step 133, the magnitudes of H and Hi are compared. If H is greater than Hi, the process proceeds to step 134a; otherwise, Hi-1 is determined in step 134b.
From the bar graph to the code number CC
It is generated in a display color i and output to the display means 17. The display means 17 displays this on a screen. Then, the operation ends. In step 134a, a bar-graph-like graphic corresponding to Hi-1 to Hi is generated in a display color having a code number CCi and output to the display means 17. Display means 17
Will output this to the screen. In step 135, steps 133 and 134a are defined as i = 1, 2,.
., N-1. If i = n-1, go to step 136; if not, return to step 133.

In step 136, a bar-graph-like graphic corresponding to Hn−1 to Hn is generated in a display color having a code number CCn and output to the display unit 17. Display means 1
7 outputs this to the screen. Then, the operation ends.

Embodiment 3 In an in-vehicle navigation device, it is generally considered that a user is often driving a vehicle. Therefore, it is useful not only to display the altitude value of the current vehicle position but also to output the altitude value as audio.

The operation will be described with reference to the flowchart of FIG. FIG. 14 is a flowchart showing the operation of the vehicle-mounted navigation device according to the present invention. In step 61, the vehicle position detecting means 13 specifies the current vehicle position. In step 62, the arithmetic means 14 calculates the elevation value of the current vehicle position from the map information extracted from the map information storage means 11 and the current vehicle position specified in step 61. In step 141, the control means 16 executes step 62.
A voice signal is generated from the altitude value of the current vehicle position calculated in the step (1), and is output to the voice output means 18. The audio output means 18 outputs this to a speaker. In step 64, it is determined whether or not to end the operation of the present apparatus. If the end of the operation is instructed by the user through the operation means 15, the operation ends. Otherwise, the process returns to step 61.

The voice is output when the user requests an altitude value through the operation means 15, and is output at regular time intervals or at regular distances. It is also conceivable that the output is made when the altitude value of the current vehicle position matches some preset values.

Embodiment 4 If only the altitude value of the current vehicle position is displayed on the display means 17 for a long time, the user may not be able to recognize the current vehicle position. Therefore, if the current altitude value of the vehicle is displayed so as to be superimposed on the map generated by the map generating means 12, it is possible to associate the altitude value with the map while recognizing the current vehicle position.

FIG. 15 shows a display example on the display means 17 according to the fourth embodiment of the present invention. On the screen 151, a map around the current vehicle position C is displayed. further,
The altitude value of the current vehicle position is displayed superimposed on the map.

Next, the operation will be described with reference to the flowchart of FIG. FIG. 16 is a flowchart showing the operation of the vehicle-mounted navigation device according to the present invention. In step 61, the vehicle position detecting means 13 specifies the current vehicle position. In step 62, the arithmetic means 14 calculates the elevation value of the current vehicle position from the map information extracted from the map information storage means 11 and the current vehicle position specified in step 61. In step 161, a map around the current vehicle position is generated from the map information extracted from the map information storage unit 11 and the current vehicle position specified in step 61. In step 162, the control unit 16 calculates the altitude value of the current vehicle position calculated in step 62 in step 16.
A video signal as shown in FIG. 15 superimposed on the map generated in 1 is generated and output to the display means 17. Display means 17
Displays this on the screen. In step 64, it is determined whether or not to end the operation of the present apparatus. If the end of the operation is instructed by the user through the operation means 15, the operation ends. Otherwise, the process returns to step 61.

Embodiment 5 FIG. When displaying the elevation value of the current vehicle position on the display means 17, the elevation value changes with the movement of the vehicle, but it may be difficult for the user to recognize the value at a glance while driving the vehicle. . When it is desired to know the approximate value of the elevation value, such a small change in the value is not necessary. Therefore, when displaying the altitude value, the value is displayed after being quantized.

Also, by changing the quantization width such that the altitude is relatively dense when the altitude is low and relatively sparse when the altitude is high, an altitude value with necessary and sufficient precision can be more easily obtained. It is possible to do.

Further, when the altitude value is quantized and displayed,
Hunting may occur near the threshold, making it impossible to recognize the altitude value. Therefore, the occurrence of hunting is prevented by giving a hysteresis characteristic when quantizing.

FIG. 17 shows a display example on the display means 17 according to the fifth embodiment of the present invention. The screen 171 displays the altitude value of the current vehicle position as a bar graph-shaped figure 172. The upper end of the figure 172 represents the altitude value of the current vehicle position. On the screen 171, unlike the screen 101, the scale 173 of the altitude value is not linear. Also, FIG.
The upper end of 2 does not take a continuous value from 0 to 3000,
Only the value shown on the scale 173 is taken.

Next, the operation will be described with reference to the flowcharts of FIGS. FIG. 18 is a flowchart showing the operation of the vehicle-mounted navigation device according to the present invention. In step 181, a quantization table for determining the quantization width of the elevation value and its threshold is created. In step 61, the vehicle position detecting means 13 specifies the current vehicle position. In step 182, the calculating means 14
In, the elevation value of the current vehicle position is calculated from the map information extracted from the map information storage means 11, the quantization table created in step 181 and the current vehicle position specified in step 61. In step 63, the control means 16 generates a video signal as shown in FIG. 17 from the altitude value of the current vehicle position calculated in step 62 and outputs it to the display means 17. The display means 17 displays this on a screen. In step 64, it is determined whether or not to end the operation of the present apparatus. If the end of the operation is instructed by the user through the operation means 15, the operation ends. Otherwise, the process returns to step 61.

FIG. 19 shows an example of the quantization table. When the altitude H increases due to the movement of the vehicle, FIG.
.., Hn-1u, the altitude values to be displayed are H0,.
, Hn. When the elevation value H decreases, as shown in FIG. 19B, h0d, h1d,.
At the threshold value of −1d, the altitude value to be displayed is changed to 0, H0,..., Hn−1.

FIG. 20 is a flowchart showing the operation for calculating the altitude value of the current vehicle position. In step 71, the elevation information of the mesh including the current vehicle position and the eight neighboring meshes is extracted from the map information storage unit 11. In step 72, several pieces near the current vehicle position are selected from the altitude information extracted in step 71. In step 73, the altitude value of the current vehicle position is calculated from the altitude information selected in step 72. In step 201, the altitude value calculated in step 72 is quantized according to the quantization table created in step 181.

The quantization table created in step 181 is defined in the control means 16 in advance.
It is conceivable that the user inputs to the control unit 16 through the operation unit 15.

Embodiment 6 FIG. The altitude information stored in the map information storage means 11 is generally the altitude of the terrain itself. Therefore, an altitude value of a vehicle position on a road structure such as a tunnel or a bridge may not be accurately represented. Since a road structure often does not change its altitude, the altitude value is not updated when it is assumed that the vehicle is currently in a tunnel or on a bridge. Thereby, for example, it is possible to prevent the altitude value from going up and down in the tunnel.

The operation will be described with reference to the flowcharts of FIGS. 21 and 22. FIG. 21 is a flowchart showing the operation of the vehicle-mounted navigation device according to the present invention. In step 61, the vehicle position detecting means 1
At 3, the current vehicle position is specified. Step 21
1, the arithmetic means 14 causes the map information storage means 11
The information of the road on which the vehicle is currently traveling is extracted from the map information extracted from the above and the current vehicle position specified in step 61. In step 212, the arithmetic unit 14 extracts the map information extracted from the map information storage unit 11,
The altitude value of the current vehicle position is calculated from the current vehicle position specified in step 61 and the information on the road on which the current vehicle is running extracted in step 211. In step 63, the control means 16 executes step 21
5 from the elevation value of the current vehicle position calculated in FIG.
A video signal as shown in FIG. 5A or FIG. 5B is generated and output to the display means 17. The display means 17 displays this on a screen. In step 64, it is determined whether or not to end the operation of the present apparatus. If the end of the operation is instructed by the user through the operation means 15, the operation ends. Otherwise, the process returns to step 61.

FIG. 22 is a flowchart showing the operation for calculating the altitude value of the current vehicle position. Step 221
Then, it is determined whether or not the road on which the vehicle is currently located is a tunnel or a bridge by referring to the structure information 43. If it is a tunnel or bridge, go to step 222; otherwise go to step 71. In step 222, the altitude value stored in the buffer provided in the arithmetic means 14 is set as the altitude value of the current vehicle position. Then, the operation ends. In step 71, the elevation information of the mesh including the current vehicle position and the eight neighboring meshes is extracted from the map information storage unit 11. In step 72, several pieces near the current vehicle position are selected from the altitude information extracted in step 71. In step 73, the altitude value of the current vehicle position is calculated from the altitude information selected in step 72. In step 223, step 7
The altitude value calculated in 3 is stored in a buffer provided in the arithmetic unit 14. Then, the operation ends.

According to the above embodiments, since the altitude value is calculated from the map information and the current vehicle position, the user can obtain the altitude value with high accuracy.

According to each of the above embodiments, since the altitude value of the current vehicle position is output as a numerical value, the user can easily obtain the altitude value.

According to each of the above embodiments, since the altitude value of the current vehicle position is output as a graphic, the user can easily obtain the altitude value.

According to each of the above embodiments, since the display color is changed according to the altitude value of the current vehicle position, there is an effect that the user can easily obtain the approximate number of the altitude value.

According to the above embodiments, since the altitude value of the current vehicle position is output as a voice, the user can obtain the altitude value while driving the vehicle without distracting the line of sight from the front.

According to each of the above embodiments, since the altitude value of the current vehicle position is superimposed on the map and displayed, the user can obtain the altitude value while confirming the current vehicle position on the map. .

According to each of the above-described embodiments, since the altitude value of the current vehicle position is displayed after being quantized, the user can easily obtain the altitude value with necessary accuracy according to the value. There is.

According to each of the above embodiments, when displaying the altitude value of the current vehicle position after quantizing it, the quantization width is changed, so that the user needs to change the altitude value according to the value. There is an effect that can be obtained with high precision.

According to each of the above-described embodiments, the user obtains an altitude value in which unnecessary fluctuations are suppressed because the hysteresis characteristic is provided when the altitude value of the current vehicle position is quantized and displayed. There is an effect that can be done.

According to each of the above embodiments, if the current vehicle is assumed to be in a tunnel or on a bridge, the altitude value is not updated, so that the user can use the altitude value in which unnecessary fluctuation is suppressed. There is an effect that can be obtained.

[0063]

The altitude information calculating apparatus according to the present invention uses the current vehicle position and the position of the area or point where the altitude information is stored in the map information storage means.
Even when the area or point where the altitude information is stored is different from the current vehicle position, the altitude value at the current position of the vehicle can be calculated, and the altitude information stored in the map information storage means can be reduced. is there.

Further, by using the position of the area where the altitude information is stored in the map information storage means and the current vehicle position, the position of the area where the altitude information is stored and the current vehicle position are used. Since the altitude value at the current position of the vehicle is calculated, the altitude information stored in the map information can be reduced, and the altitude of the current vehicle position can be accurately calculated by using the position of the area. You can do it.

Further, by using the position of the point where the altitude information is stored in the map information storage means and the current vehicle position, when the point where the altitude information is stored differs from the current vehicle position. However, the altitude value at the current position of the vehicle can be calculated, and the altitude of the current vehicle position can be accurately calculated by using the position of the point where the altitude information is stored.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a vehicle-mounted navigation device according to the present invention.

FIG. 2 is an example of the configuration of a vehicle-mounted navigation device according to the present invention.

FIG. 3 is an example of a storage form of elevation information in a map storage unit.

FIG. 4 is an example of a storage form of altitude information in a map storage unit.

FIG. 5 is a display example on a display unit of the first embodiment.

FIG. 6 is a flowchart showing an operation of the first embodiment.

FIG. 7 is a flowchart showing an operation of calculating an altitude value of a current vehicle position.

FIG. 8 is an example of calculating an altitude value of a current vehicle position.

FIG. 9 is a calculation example of an altitude value of a current vehicle position.

FIG. 10 is a display example on a display unit according to the second embodiment.

FIG. 11 is a flowchart showing an operation of the second embodiment.

FIG. 12 is an example of an altitude value-display color correspondence table.

FIG. 13 is a flowchart showing an operation of displaying an altitude value of a current vehicle position.

FIG. 14 is a flowchart illustrating the operation of the third embodiment.

FIG. 15 is a display example on a display unit according to the fourth embodiment.

FIG. 16 is a flowchart showing an operation of the fourth embodiment.

FIG. 17 is a display example on a display unit according to the fifth embodiment.

FIG. 18 is a flowchart showing the operation of the fifth embodiment.

FIG. 19 is an example of a quantization table.

FIG. 20 is a flowchart illustrating an operation of calculating an altitude value of a current vehicle position.

FIG. 21 is a flowchart showing the operation of the sixth embodiment.

FIG. 22 is a flowchart showing an operation of calculating an altitude value of a current vehicle position.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Map information storage means 12 Map generation means 13 Intersection guide map generation means 14 Calculation means 15 Operation means 16 Control means 17 Display means 18 Voice output means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Keiki Kishigami 2-3-2 Marunouchi, Chiyoda-ku, Tokyo In-house Mitsubishi Electric Corporation (72) Inventor Masao Saga 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi (72) Inventor Shigeki Nakane 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Corporation

Claims (3)

[Claims] 1. A map information storage means for storing altitude information corresponding to an area or a point, a vehicle position detecting means for detecting a current vehicle position, a position of the area or the point,
Means for calculating an altitude value at the current vehicle position based on the current vehicle position and altitude information of the area or point. 2. A map information storage means for storing altitude information corresponding to an area, a vehicle position detection means for detecting a current vehicle position, and selecting an area near an area including the current vehicle position. Means for calculating an elevation value at the current vehicle position based on the position of the area including the current vehicle position, the current vehicle position, and the elevation information of the selected area. Calculation device. 3. A map information storage means for storing elevation information corresponding to a point, a vehicle position detection means for detecting a current vehicle position, and two points close to the current vehicle position are selected. Means for calculating an altitude value at a current vehicle position based on the selected two positions, the current vehicle position, and the altitude information of the selected two points.