JP2001324342A - Navigation system, route cost displaying method, and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a navigation system properly displaying a route cost of each of routes branching at an intersection and the like. SOLUTION: A process controlling part obtains a present position of an own vehicle (step S11) according to position information fed from a GPS module so as to produce a navigation image (step S12). The process controlling part determines whether it is before a guide point or not (step S13). If it is determined to be before the guide point, the process controlling part carries out route cost computing for computing route costs necessary for reaching a destination via respective routes branched in the guide point (step S14). The process controlling part produces a route cost image and an arrow symbol (step S15) so as to combine them into a navigation image (step S16). The process controlling part indicates the combined navigation image in a display part (step S17).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation system, a route cost display method, and a recording medium capable of appropriately displaying the route cost of each route branching at an intersection or the like.

[0002]

2. Description of the Related Art A conventional navigation system is, for example, a vehicle equipped with a navigation system (hereinafter referred to as a vehicle).
It is called "own car". The search for the guidance route from the departure point to the destination is performed, and the retrieved guidance route is displayed together with the map image on a predetermined monitor or the like. Also, the navigation system
A symbol or the like indicating the current position of the vehicle is synthesized and displayed on a map image or the like. Thus, the user can easily reach the destination by driving the own vehicle along the guidance route.

Hereinafter, a conventional navigation system will be described with reference to the drawings. FIG. 6 is a block diagram showing an example of a conventional navigation system. As shown in the figure, the navigation system includes a navigation device 100 that is a device main body and a monitor 200 that displays a map image and the like. Navigation device 1
00 includes, for example, map data 101 recorded on a CD-ROM, and a storage unit 107 including a RAM or the like. A route search function 102, a route guidance function 103, a map display function 104, a position detection function 105, and Screen display function 10
6.

The position detecting function 105 is a GPS (Global P
ositioning System) Receives satellite radio waves sent from satellites and detects the current position of the vehicle (own vehicle position). The map display function 104 reads the map data 101 as appropriate according to the own vehicle position detected by the position detection function 105 and draws a map image. When a destination or the like is input from a predetermined operation unit, the route search function 102 searches the map data 101 to obtain a guidance route from the vehicle position or the like detected by the position detection function 105 to the destination. . This guidance route is a route that can reach the destination in the shortest time, for example.

The route guidance function 103 includes a route search function 10
When the guidance route is searched for by 2, the display color or the like of the searched guidance route is changed and is superimposed on the map image drawn by the map display function 104. The screen display function 106 displays the map image drawn by the map display function 104 or the like on the monitor 20.
Display at 0. For example, the screen display function 106 corresponds to FIG.
As shown in (a), the symbol 201 indicating the vehicle position and the guidance route 20 obtained by the route search function 102
2 is displayed on the monitor 200.

When the vehicle approaches a predetermined guide point (for example, an intersection requiring an instruction to turn left or right), the route guidance function 103 instructs the screen display function 106 to follow the guidance route. It requests the display of an arrow symbol or the like for indicating the direction to go (turn). Then, the screen display function 106 displays, for example, an arrow symbol 203 for instructing a right turn on the map image as shown in FIG. 7B.

Accordingly, the user recognizes the arrow symbol 203 and the like displayed before the guide point, and drives the vehicle according to the arrow symbol 203 and the like.
It is possible to reach the destination without departing from the guidance route 202.

[0008]

As described above, in the conventional navigation system, the guidance route and the like searched by the route search function 102 are superimposed and displayed on the map image. That is, a map image including the guidance route 202 shown in FIG. Then, the user is guided in the order of the points A, B, and F in the figure, and the user can reach the destination. Here, if the section from the current location to the point B via the point A is congested, the user wants to drive to the destination while avoiding the route between the points A and B. In this case, point A is the intersection of a crossroad,
To avoid the route between points A and B,
It is necessary to proceed along the route between the points D.

[0009] However, the conventional navigation system only displays the arrow symbol 203 or the like along the guidance route 202 as shown in FIG. 7B in front of the guide point. It is difficult to determine which route between the points C and points A and D should be selected to proceed.

In recent years, VICS (Vehicle Information and Communication) that provides traffic congestion information and traffic regulation information to users via optical / radio beacons or FM multiplex broadcasting.
System) The system has been developed, but it is limited to urban areas and many other areas are not supported. Also, traffic information and the like supplied by such a VICS system have a certain delay before being sent. Therefore, it is not possible to obtain information on traffic congestion newly generated due to an accident or construction immediately after the accident.

That is, even in a navigation system compatible with the VICS system, there is a case where the driver must deviate from the guidance route and proceed with the own vehicle due to a newly generated traffic jam. Even in such a case, the user may be confused as to which route to select because the user deviates from the guidance route.

The present invention has been made in view of the above situation, and provides a navigation system, a route cost display method, and a recording medium capable of appropriately displaying the route cost of each route branching at an intersection or the like. With the goal.

[0013]

In order to achieve the above object, a navigation system according to a first aspect of the present invention comprises: a map image generating means for generating a map image to be displayed according to predetermined map information; A guide point obtaining means for obtaining a guide point existing on the route in the traveling direction of the own vehicle; and specifying a plurality of branch roads branching from the guide point obtained by the guide point obtaining means, and determining an objective from each of the specified branch roads. Route search means for searching for each route to the ground, route cost calculation means for calculating the route cost of each route searched by the route search means, and information indicating the route cost calculated by the route cost calculation means. And display means for combining and displaying the map image generated by the map image generation means.

According to the invention, the map image generating means includes:
A map image to be displayed is generated according to predetermined map information. The guide point obtaining means obtains a guide point existing on the route in the traveling direction of the own vehicle. The route searching means specifies a plurality of branch roads branching from the guide point obtained by the guide point obtaining means, and searches for each of the routes from each of the specified branch roads to the destination. The route cost calculation means calculates a route cost of each route searched by the route search means. The display unit combines information indicating the route cost calculated by the route cost calculation unit with the map image generated by the map image generation unit and displays the combined image. As a result, the route cost of each route that branches at an intersection or the like can be appropriately displayed.

To achieve the above object, a navigation system according to a second aspect of the present invention includes a road network information storage unit that stores road network information including at least node information and link information, and indicates a current location of the vehicle. Position information acquiring means for acquiring position information, and a map image generating means for identifying a display target area from predetermined map information according to the position information acquired by the position information acquiring means, and generating a map image of the identified area. Guide point obtaining means for obtaining a guide point present on the route in the traveling direction according to the position information obtained by the position information obtaining means; and the guidance from the road network information stored in the road network information storage means. Route search means for searching each route to a destination through a plurality of branch roads branching from the guide point obtained by the point obtaining means,
A route cost calculating means for calculating the required time and distance of each route searched by the route searching means, and information indicating the required time and distance calculated by the route cost calculating means, the map generated by the map image generating means. Display means for combining and displaying the image.

According to the present invention, the road network information storage means stores road network information including at least node information and link information. The position information obtaining means obtains position information indicating the current location of the vehicle. The map image generation means specifies an area to be displayed from predetermined map information according to the position information acquired by the position information acquisition means, and generates a map image of the identified area. The guide point obtaining means obtains a guide point present on the route in the traveling direction according to the position information obtained by the position information obtaining means. The route search means searches for each route from the road network information stored in the road network information storage means to the destination through a plurality of branch roads branching from the guide point obtained by the guide point obtaining means. The route cost calculation means calculates the required time and distance of each route searched by the route search means. The display unit combines the information indicating the required time and the distance calculated by the route cost calculation unit with the map image generated by the map image generation unit and displays it.
As a result, the route cost of each route that branches at an intersection or the like can be appropriately displayed.

To achieve the above object, a route cost display method according to a third aspect of the present invention includes a map image generating step of generating a map image to be displayed according to predetermined map information; A guide point obtaining step of obtaining a guide point existing on the route in the direction, and specifying a plurality of branch roads branching from the guide point obtained in the guide point obtaining step, from the specified branch road to the destination. A route search step of searching for each route to the route, a route cost calculation step of calculating a route cost of each route searched in the route search step, and a route cost calculated in the route cost calculation step. A display step of combining the information with the map image generated in the map image generation step and displaying the information on a predetermined display unit.

According to the present invention, the map image generating step generates a map image to be displayed according to the predetermined map information. The guide point obtaining step obtains a guide point existing on the route in the traveling direction of the vehicle. In the route search step, a plurality of branch roads branching from the guide point acquired in the guide point acquisition step are specified, and respective routes from each of the specified branch roads to the destination are searched. The route cost calculation step calculates a route cost of each route searched in the route search step. The display step includes information indicating the route cost calculated in the route cost calculation step,
The image is combined with the map image generated in the map image generation step and displayed on a predetermined display unit. As a result, the route cost of each route that branches at an intersection or the like can be appropriately displayed.

To achieve the above object, a recording medium according to a fourth aspect of the present invention comprises: a map image generating step of generating a map image to be displayed according to predetermined map information; A guide point obtaining step of obtaining a guide point present on the route, and specifying a plurality of branch roads branching from the guide point obtained in the guide point obtaining step,
A route search step of searching for a route from each of the specified branch roads to the destination; a route cost calculation step of calculating a route cost of each route searched in the route search step; and a route cost calculation step Combining the information indicating the route cost calculated in the above step with the map image generated in the map image generating step, and displaying the route image on a predetermined display unit. Record the program.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A navigation system according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing an example of a navigation system applied to an embodiment of the present invention.
This system includes a GPS antenna 1, a GPS module 2, a processing control unit 3, a CD-ROM 4, and a storage unit 5.
, An operation unit 6 and a display unit 7. This navigation system is mounted on a vehicle such as an automobile, for example.
The user is appropriately guided to the destination by displaying a guidance route indicating a route to be traveled from the departure point to the destination together with map information and the like. Hereinafter, a vehicle equipped with a navigation system is referred to as “own vehicle”.

The GPS (Global Positioning System) antenna 1 is composed of a helical antenna, a dielectric antenna, a patch type planar antenna, and the like, and receives a spread spectrum modulated satellite wave transmitted from a predetermined GPS satellite.

The GPS module 2 tunes to satellite radio waves transmitted from a plurality of GPS satellites and received by the GPS antenna 1, and despreads and demodulates each satellite radio wave to obtain a plurality of satellite reception signals. The GPS module 2 generates position information including a latitude, a longitude, an altitude, and the like, based on a difference in arrival time of each satellite radio wave calculated according to each of the acquired satellite reception signals. The GPS module 2 supplies the generated position information to the processing control unit 3 at every predetermined timing.

The processing control unit 3 is, for example, a ROM (Read O
nly Memory), RAM (Random Access Memory), CP
A one-chip microcomputer or the like having a U (Central Processing Unit), a position detecting unit 31 and a route searching unit 32
, A route cost calculation unit 33, a map drawing unit 34, a route guidance unit 35, and a display control unit 36.

The position detecting section 31 detects the current position of the own vehicle (own vehicle position) by performing map matching or the like according to the position information sent from the GPS module 2. The position detection unit 31 supplies information defining the detected vehicle position to the route search unit 32, the map drawing unit 34, and the like.

The route search unit 32 searches for a guide route from a departure place to a destination, for example, from road network information stored in a CD-ROM 4 described later. The route search unit 32 stores in the storage unit 5 guidance route information that defines the searched guidance route. Further, the route search unit 32 searches for a route that reaches each destination from each branch road at a guide point such as an intersection at a predetermined timing.

The route cost calculation unit 33 includes a route search unit 32
The route cost (required time and distance) of each route from each branch road of the guide point searched for to the destination is calculated.

The map drawing section 34 appropriately reads out the map information stored in the CD-ROM 4 according to the position of the vehicle detected by the position detection section 31 and draws a map image to be displayed. At this time, the map drawing unit 34 specifies the guidance route according to the guidance route information stored in the storage unit 5, and changes the display color or the like of the guidance route and draws the guidance route. Also, the map drawing unit 3
4 also draws a symbol indicating the position of the vehicle at a corresponding position on the map image. That is, the map drawing unit 34 generates a map image (navigation image) including a guidance route, a vehicle position symbol, and the like.

The route guidance unit 35 generates a route cost image (character image) representing the route cost calculated by the route cost calculation unit 33 when the own vehicle approaches the guide point existing at the destination. In addition, the route guidance unit 35 generates an arrow symbol or the like indicating a direction in which the vehicle should proceed (turn) along the guidance route.

The display control unit 36 displays the map image generated by the map drawing unit 34 on the display unit 7. When a route cost image or the like is generated by the route guidance unit 35, the display control unit 36 combines the route image with the map image and displays the combined image on the display unit 7.

The CD-DOM 4 stores predetermined map information for display and also stores road network information including information such as road links and road nodes. The road link is predetermined section information constituting each road, and includes position coordinates, distance,
It consists of the required time. The road node is information on intersections (branches) and the like, and is composed of position coordinates, connection destination road links, and the like.

A predetermined road link and a road node are searched from such road network information to obtain, for example, a combination of a route connecting a departure point and a destination to minimize a distance or a required time. Determines the guidance route. The CD-ROM 4 supplies map data, road network information, and the like to the route search unit 32, the map drawing unit 34, and the like via a driver unit (not shown). The storage unit 5
It is composed of a RAM or the like, and stores, for example, guidance route information that defines a guidance route that defines a route to go from a departure place to a destination. The guide route information is a road link, a road node, and the like searched by the route search unit 32 from the road network information stored in the CD-ROM 4.

The operation unit 6 comprises a predetermined operation panel and the like, and supplies various information to the processing control unit 3 according to an input operation by a user. For example, the operation unit 6 inputs coordinate information or the like specifying a destination according to a user operation, and supplies the coordinate information to the processing control unit 3.

The display unit 7 is a liquid crystal display (LCD).
Play) or a CRT (Cathode Ray Tube), and displays a map image in which a route cost image and the like are combined according to control from the display control unit 36.

Hereinafter, the operation of the navigation system according to the embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a flowchart for explaining the navigation processing. The navigation process shown in FIG. 2 is started, for example, after a guidance route from a departure point to a destination is searched and guidance information defining a guidance route is stored in the storage unit 5.

First, the processing control section 3 acquires the current position of the own vehicle according to the position information sent from the GPS module 2 (step S11). That is, the position detector 31
, Map matching and the like are performed, and the position of the own vehicle is detected.

The processing control section 3 generates a navigation image (step S12). That is, the map drawing unit 34
The CD-ROM contains the map information including the acquired vehicle position at
4, a navigation image is generated in which symbols indicating the position of the vehicle, guidance routes, and the like are combined on the map image. For example, as shown in FIG. 3A, the map drawing unit 34 generates a navigation image obtained by synthesizing a symbol 71 indicating the vehicle position, a guidance route 72 with a predetermined display color, and the like on a map image. I do.

The processing control section 3 determines whether or not it is before the guide point (step S13). That is, the processing control unit 3
Is a CD-intersection where you need to give instructions such as turning left and right.
The vehicle is specified in accordance with the road network information stored in the ROM 4, and it is determined whether or not the own vehicle has arrived a predetermined distance before the specified intersection or the like.

If the processing control section 3 determines that the point is not before the guide point, the processing advances to step S17 described later.
On the other hand, if it is determined that it is before the guide point, the processing control unit 3 executes a route cost calculation process (step S1).
4). That is, the process control unit 3 executes a route cost calculation process for calculating a route cost (required time and distance) when traveling to the destination through each route branched at the guide point. The details of the route cost calculation processing will be described later.

The processing control section 3 generates a path cost image and an arrow symbol (step S15). That is, the route guidance unit 35 generates a route cost image (character image) for displaying the calculated route costs, and an arrow symbol image indicating the direction in which the vehicle should proceed along the guidance route.

The processing control section 3 combines the navigation image with the route cost image and the like (step S16). That is, the display control unit 36 combines the navigation image generated by the map drawing unit 34 with the route cost image generated by the route guidance unit 35 and the arrow symbol.

For example, as shown in FIG. 3B, the display control unit 36 generates a route cost image 73 corresponding to each route branching from the guide point A, and an arrow indicating the direction in which the vehicle should proceed along the guide route 72. The symbol 74 is combined with the navigation image.

The processing control section 3 displays the navigation image on the display section 7 (step S17). That is, after the display controller 36 converts the navigation image into a predetermined video signal, the navigation image is displayed on the display 7.

The processing control section 3 determines whether or not the vehicle has arrived at the destination (step S18). If the process control unit 3 determines that the vehicle has not arrived at the destination, the process returns to step S11, and repeats the processes of steps S11 to S18 described above. On the other hand, when it is determined that the vehicle has arrived at the destination, the processing control unit 3 ends the navigation processing.

Next, the route cost calculation processing in step S14 will be described in detail with reference to FIG. FIG. 4 is a flowchart for explaining the route cost calculation process.

First, the processing control section 3 specifies the number of branches that can be guided at the guide point (step S21). That is, the number of branch roads at which the vehicle can travel at the guide point (excluding the route on which the vehicle is traveling) is specified.

The processing control unit 3 sets the variable i to the initial value “1”.
Is set (step S22). Note that the variable i is used to specify (or count) the branch road during the calculation process.

The processing control section 3 searches for a route from the branch road i to the destination (step S23). That is, the route search unit 32 searches for a plurality of routes that reach the destination through the branch road i.

The processing control section 3 calculates the required time and distance of the shortest route (step S24). That is, the route cost calculation unit 33 specifies the shortest route from the plurality of routes searched by the route search unit 32, and calculates the route cost (required time and distance) of the shortest route.

The processing control section 3 adds 1 to the variable i (step S25). The process control unit 3 determines whether or not the variable i is larger than the number of branches that can be guided at the guide point (step S26).

When the processing control section 3 determines that the variable i is not larger than the number of branch roads (it is equal to or less than the number of branch roads), the processing returns to step S23 and the above-mentioned steps S23 to S23 are performed.
Step 26 is repeated. On the other hand, when it is determined that the variable i is larger than the number of branch roads, the processing control unit 3 finishes the route cost calculation processing and proceeds to step S
The process returns to step 15.

By this route cost calculation processing, respective route costs (required time and distance) when traveling to the destination through each branch road at the guide point are calculated.

Then, in the above navigation processing,
Each route cost image is displayed on the display unit 7 together with the navigation image. As a result, the route cost of each route branching at an intersection or the like is displayed, so that even when the user must proceed to a route different from the guidance route, each route cost displayed together with the navigation image is displayed. , A more appropriate route can be selected.
That is, the user can select a more appropriate route in consideration of the displayed static route cost without acquiring the dynamic route cost based on the VICS information or the like.

In the above embodiment, the case where traffic information such as VICS information is not used has been described.
Similar effects can be obtained in a navigation system compatible with the S system. That is, VIC
Even when the S information cannot be received, or when the appropriate current road conditions cannot be obtained due to the delay of the transmission of the VICS information, the user can check each route cost displayed,
For example, it is possible to select a more appropriate route in consideration of a road condition that can be viewed.

In the above embodiment, the calculated route cost is displayed as a character image. However, the present invention is not limited to the character image, and a symbol or the like for identifying the magnitude of the route cost may be displayed. Furthermore, according to the calculated route cost, the route may be displayed in a different display color or shade. For example,
As shown in FIG. 5A, a route 7 branching from the guide point A
The display colors of 5, 76 and 77 may be changed and displayed according to the route cost.

In this case, since traveling to the destination in the order of points ABF shown in FIG. 5A is the shortest and the shortest distance, the route 75 is displayed in the darkest color. In addition, the next shortest time or the like is required to proceed to the destination in the order of the points ACF, so that the route 76 is displayed in a slightly lighter color than the route 75. Then, traveling to the destination in the order of A-D-E-C-F-F is the longest and longest distance, so that the route 77 is displayed in the lightest color.

In the above embodiment, the route cost image (character image) is displayed near each branch road, but the display position of the route cost image is arbitrary. For example, FIG.
As shown in (b), directions that can be guided (travelable) at the guide point may be displayed by an arrow symbol, and the route cost in each direction may be displayed together. In this case, since the display is simplified, the user can easily visually recognize the route cost of each route.

In the above embodiment, the route cost to the destination is displayed, but the route cost to another target may be displayed. For example, when a waypoint (stop-off point) or the like is set, the route cost from the guide point to the waypoint may be displayed. Further, the route cost from the guide point to the guide point may be displayed.

The navigation system according to the embodiment of the present invention can be realized by using a general computer system without using a dedicated system. For example, by installing the program from a medium (floppy (registered trademark) disk, CD-ROM, or the like) storing a program for executing any of the above-described processes into a computer having a GPS reception function, the above-described processing is performed. A navigation system to execute can be configured.

The method for supplying the program to the computer is arbitrary. For example, the information may be supplied via a communication line, a communication network, a communication system, or the like. As an example, a bulletin board (BB) of a communication network
The program is posted on S) and distributed via a network. And start this program, O
Under the control of S, the above-described processing can be executed by executing the program in the same manner as other application programs.

[0061]

As described above, according to the present invention,
The route cost of each route branching at an intersection or the like can be appropriately displayed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a configuration of a navigation system according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a navigation process according to the embodiment of the present invention.

3A is a schematic diagram illustrating an example of a navigation image generated by a map drawing unit, and FIG. 3B illustrates an example of a navigation image in which a route cost image and the like are combined by a display control unit; It is a schematic diagram.

FIG. 4 is a flowchart illustrating a route cost calculation process according to the embodiment of the present invention.

5A is a schematic diagram illustrating an example of a route display in which the shading of a color or the like is changed according to a route cost, and FIG. 5B is an arrow symbol indicating a traveling direction at a guide point and a route cost in each direction. It is a schematic diagram which shows an example of a display of.

FIG. 6 is a block diagram showing an example of a conventional navigation system.

7A and 7B are schematic diagrams illustrating an example of an image displayed by a conventional navigation system, in which FIG. 7A is a diagram illustrating a map image including a guidance route, and FIG. It is a figure showing the map image containing the arrow symbol which shows the power direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 GPS antenna 2 GPS module 3 Processing control unit 4 CD-ROM 5 Storage unit 6 Operation unit 7 Display unit 31 Position detection unit 32 Route search unit 33 Route cost calculation unit 34 Map drawing unit 35 Route guidance unit 36 Display control unit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C032 HB22 HB24 HC26 HC27 HD03 HD07 HD21 2F029 AA02 AB07 AB13 AC02 AC09 AC13 AC16 5H180 AA01 BB13 CC12 FF05 FF13 FF22 FF24 FF32 FF35 FF38 5J062 AA03 BB01 CC07 H07

Claims (4)

[Claims] 1. A map image generating means for generating a map image to be displayed in accordance with predetermined map information; a guide point obtaining means for obtaining a guide point present on a route in a traveling direction of a vehicle; A route search unit that specifies a plurality of branch roads branching from the guide point obtained by the point obtaining unit and searches for each route from each of the specified branch roads to the destination; and each of the routes searched by the route search unit. Route cost calculating means for calculating the route cost, and display means for combining and displaying information indicating the route cost calculated by the route cost calculating means with the map image generated by the map image generating means. A navigation system characterized by the following. 2. A road network information storage unit for storing road network information including at least node information and link information; a position information obtaining unit for obtaining position information indicating a current position of the own vehicle; Map image generating means for specifying an area to be displayed from predetermined map information according to the specified position information and generating a map image of the specified area; and a route in a traveling direction according to the position information obtained by the position information obtaining means. A guide point obtaining means for obtaining a guide point present on the road, from the road network information stored in the road network information storage means,
Route search means for searching for each route leading to a destination through a plurality of branch roads branching from the guide point obtained by the guide point obtaining means; required time and distance of each route searched by the route search means And a display unit that combines information indicating the required time and distance calculated by the route cost calculating unit with the map image generated by the map image generating unit and displays the combined information. A navigation system characterized by the following. 3. A map image generating step of generating a map image to be displayed in accordance with predetermined map information; a guide point obtaining step of obtaining a guide point existing on a route in a traveling direction of the vehicle; A route search step of specifying a plurality of branch roads branching from the guide point obtained in the point obtaining step and searching for a respective route from each of the specified branch roads to the destination; and searching in the route search step A route cost calculation step of calculating the calculated route cost of each route, and combining the information indicating the route cost calculated in the route cost calculation step with the map image generated in the map image generation step, and And a display step of displaying on a display unit of (1). 4. A map image generating step for generating a map image to be displayed in accordance with predetermined map information; a guide point obtaining step for obtaining a guide point existing on a route in the traveling direction of the vehicle; A route search step of specifying a plurality of branch roads branching from the guide point obtained in the point obtaining step and searching for a respective route from each of the specified branch roads to the destination; and searching in the route search step A route cost calculating step of calculating the calculated route cost of each route, and information indicating the route cost calculated in the route cost calculating step, and combining the information with the map image generated in the map image generating step, and A computer readable recording program for causing a computer to execute a route cost display method having a display step of displaying on a display unit Recording media.