JP2007263791A - Navigation device, control method therefor and control program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a navigation device, a navigation method and a navigation program capable of providing detailed congestion information required by user, by displaying the degree of congestion provided in three stages, in the divided state into finer sections, concerning road traffic information acquired from the outside. <P>SOLUTION: A road traffic information analysis part 32 extracts only link traveling time information from VICS information, reads out the link length of the link in a map database stored in a storage device 11, based on the link travel time information, and calculates the average passing time of the link from the link length, corresponding to the link travel time information. A congestion degree calculation part 33 determines the average passing time of each link from the result, and classifies it in detail (for example, into five sections), and calculates the degree of congestion. A display control part 34 displays, regarding each degree of congestion in display modes changed, on a map screen. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technology for providing detailed and useful traffic jam information to a user based on road traffic information obtained from the outside in a navigation device.

  In recent years, navigation devices typified by in-vehicle use have become widespread as devices for assisting safe and comfortable driving, and are equipped with various functions. For example, there is provided a function of notifying a user by acquiring traffic information (location and length of a traffic jam) related to a guidance route to a destination and displaying the traffic information on a screen or reading it out by voice. VICS (Vehicle Information and Communication System) information is well known as traffic information. As information levels of VICS information, there are traffic congestion information in characters (level 1), simple figure information of main national roads (level 2), and information (level 3) for displaying traffic congestion sections and emergency evacuation points on the screen. Moreover, it is divided roughly into information by FM multiplexing, and information by an electric wave beacon or an optical beacon according to a transmission form.

In such VICS information, for example, traffic information by FM multiplexing is transmitted to the entire area under the jurisdiction of the broadcasting station, so that the user can acquire a wide range of information regardless of the traveling direction of the vehicle. On the other hand, it has the disadvantage of providing unnecessary information to the user. Therefore, as a technique for utilizing such VICS information conventionally, for example, only the traffic information related to the route selected by the user and the guide route is extracted from the acquired traffic information, and traffic is extracted based on the extracted traffic information. One that displays changes in the situation has been proposed (see Patent Document 1). Further, a technique for providing traffic information suitable for the traveling direction of the vehicle by specifying the direction of the vehicle and appropriately grasping the road targeted for the provided traffic information has been proposed (Patent Document 2). reference). Thereby, it is possible to appropriately present only useful traffic information required by the user.
JP 2002-310694 A Japanese Patent Laid-Open No. 5-120597

  By the way, among the information provided by VICS, regarding the traffic jam information, the traffic jam status is provided for each link as “traffic congestion”, “congested” and “smooth” in three stages. In the navigation device, the level of traffic congestion on the map screen is indicated by the level 3 information, with “congestion” as a red line, “congestion” as an orange line, and “smooth” as a green line. It is supposed to be displayed along.

Each degree of congestion is classified according to the average passing speed as shown in the table of FIG. 7 and the following.
(1) Traffic jam: 10km / h or less for general roads, 20km / h or less for urban highways, 40km / h or less for intercity highways
(2) Congestion: 10 to 20km / h for general roads, 20 to 40km / h for urban highways, 40 to 60km / h for intercity highways
(3) Smooth: General roads are 20km / h or more, urban highways are 40km / h or more, intercity highways are 60km / h or more. In addition, urban highways here mean urban highways, For example, the metropolitan expressway is indexed. The intercity expressway is an intercity expressway, for example, Tomei Expressway.

  However, in the current three-stage classification, as described above, the range of average speed is wide, with “traffic jam” ranging from 0 to 20 km / h and “smooth” being 40 km / h or higher (in the case of urban high speeds). Therefore, for example, traffic closures (average speed is almost 0 km / h) and traffic concentration traffic jams (average speed about 20 km / h) may both be displayed as “traffic congestion (red)” or even at 40 km / h. There is a problem that the actual traffic situation cannot be accurately expressed in the three-stage classification, such as being displayed in “smooth (green)” even at 80 km / h.

  Conventionally, information required by a user is extracted from information obtained from VICS and provided, but the obtained information is not acquired as more detailed information. Then, this problem has not been solved.

  The present invention solves the above-described problems of the prior art, and its purpose is to display the traffic congestion degree provided in three stages in road traffic information obtained from the outside by dividing it into finer sections. Accordingly, an object of the present invention is to provide a navigation device capable of providing more detailed traffic jam information required by a user, a control method thereof, and a control program.

  In order to solve the above-described problems, the invention of claim 1 is directed to a storage unit that stores in advance road map data for route search and map display and facility data including the location of the facility, and a display for displaying information. And receiving means for receiving road traffic information obtained from outside the vehicle, and the road traffic information includes at least a link travel time, and the link corresponding to the link travel time received by the reception means. Road traffic information analysis means for reading out the link length from the road map data, calculating the average transit time of the link from the link travel time and the link length, and determining the degree of congestion at multiple stages based on the average transit time And a display control means for outputting to the display unit so as to be distinguished for each congestion degree.

  The invention of claim 4 captures the invention of claim 1 from the viewpoint of a method, and stores a road map data for route search and map display and facility data including the location of the facility in advance, In a method for controlling a navigation device comprising a display unit for displaying information, a process for receiving road traffic information obtained from outside the vehicle, and the road traffic information includes at least a link travel time, and the reception A road traffic information analysis process for reading out the link length of the link corresponding to the link travel time received by the means from the road map data, and calculating an average transit time of the link from the link travel time and the link length; A table for outputting to the display unit so that it can be distinguished for each congestion degree, and a congestion determination process for determining a plurality of congestion degrees based on the average transit time And a control process, the control unit or a computer and executes.

  The invention of claim 7 captures the inventions of claims 1 and 4 from the viewpoint of a computer program, and stores road map data for route search and map display and facility data including the location of the facility in advance. In a control program for a navigation device comprising a storage unit and a display unit for displaying information, the program includes at least reception processing for receiving road traffic information obtained from the outside of the vehicle, and the road traffic information. Link travel time is included, the link length of the link corresponding to the link travel time received by the receiving means is read from the road map data, and the average transit time of the link is calculated from the link travel time and the link length. The road traffic information analysis process that calculates the traffic level and the traffic level determination process that determines the multiple levels of traffic level based on this average transit time When, wherein the display control processing for output to the display unit so as to be distinguished for each of the congestion degree, that is executed by a computer or controller.

  In the aspect as described above, the road traffic information analyzing means calculates the link length of the link stored in the road map data based on the link travel time information included in the road traffic information obtained from outside the vehicle such as VICS information. Read out, calculate the average transit time of each link from here, and the congestion degree calculation means obtains the link passing speed based on the average transit time for each link from this calculation result, and subdivides this to determine the congestion degree Ask. The display control means displays each of the obtained congestion levels on the map screen by changing the display mode according to the congestion level. As a result, the traffic congestion degree that has been divided into the three conventional sections is divided into smaller sections and displayed, so that more detailed traffic congestion information corresponding to the traffic congestion speed can be provided to the user.

According to a second aspect of the present invention, in the first aspect of the present invention, the congestion degree determining means determines the congestion degree in five stages of a congestion 1, a congestion 2, a congestion, a smooth 1, and a smooth 2. .
The invention of claim 5 captures the invention of claim 2 from the viewpoint of a method. In the invention of claim 4, the congestion degree determination processing is performed by changing the congestion degree to congestion 1, congestion 2, congestion, and smoothness. It includes a process of determining 1 level and 5 levels of smoothness.
The invention of claim 8 captures the inventions of claims 2 and 5 from the viewpoint of a computer program. In the invention of claim 7, the process of determining the degree of traffic congestion is the traffic jam, It is characterized in that it is determined in five stages of traffic jam 2, congestion, smoothness 1 and smoothness 2.

  In the above-described aspect, the degree of congestion is divided into five levels of traffic jam 1, traffic jam 2, congestion, smooth 1 and smooth 2, and each of them is displayed with different display modes, so that the traffic congestion has been divided into three categories in the past. Can be divided and displayed in more detailed sections. In particular, in the case of traffic information on an expressway in a city in VICS information, the range of average speed is wide such that “traffic jam” is 0 to 20 km / h and “smooth” is 40 km / h or more. Both traffic closures due to accidents and traffic congestions with an average speed of about 20 km / h were both displayed as “traffic”, or “smooth” at either 40 km / h or 80 km / h. In the stage division, these average speed ranges can be divided in half.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the road traffic information includes traffic congestion level information, and is obtained from the traffic congestion level determined by the traffic congestion level determining means and the road traffic information. Congestion degree determination means for determining a difference from the congestion degree, and the display control means is the congestion degree determined by the congestion degree determination means by the congestion degree determination means and the congestion degree obtained from the road traffic information. And the traffic congestion degree determined by the traffic congestion degree determining means is output to the display unit, and when the traffic congestion degree obtained from the road traffic information does not match, the traffic congestion degree is obtained from the road traffic information. The degree of traffic congestion is output to the display unit.

  The invention of claim 6 captures the invention of claim 3 from the viewpoint of a method. In the invention of claim 4 or 5, the road traffic information includes congestion degree information, and the congestion degree determination processing is performed. A congestion degree determination process for determining a difference between the congestion degree determined by the traffic degree and the congestion degree obtained from the road traffic information, and the display control process is determined by the congestion degree determination process by the congestion degree determination process. When the traffic congestion level obtained matches the traffic congestion level obtained from the road traffic information, the traffic congestion level determined by the traffic congestion level determination process is output to the display unit, and the traffic congestion obtained from the road traffic information When the degree does not match, it includes a process of outputting the degree of congestion obtained from the road traffic information to the display unit.

  The invention of claim 9 captures the inventions of claims 3 and 6 from the viewpoint of a computer program. In the invention of claim 7 or 8, the road traffic information includes congestion degree information, A congestion degree determination process for determining a difference between the congestion degree determined by the process for determining the congestion degree and the congestion degree obtained from the road traffic information, and the display control process includes the congestion degree determination process, When the congestion level determined by the congestion level determination process matches the congestion level obtained from the road traffic information, the congestion level determined by the congestion level determination process is output to the display unit, and the road When the traffic congestion degree obtained from the traffic information does not match, the traffic congestion degree obtained from the road traffic information is output to the display unit.

  In the above-described aspect, the congestion degree determination means checks the congestion degree uniquely calculated by the congestion degree calculation means by comparing with the congestion degree obtained from the external road traffic information. By displaying the obtained traffic level with priority, the accuracy of the traffic level information display can be improved, and more accurate traffic information can be provided to the user.

  According to the present invention, in road traffic information obtained from the outside, the degree of congestion provided in three stages is divided and displayed in finer sections, thereby providing more detailed congestion information required by the user. A possible navigation device, a control method thereof, and a control program can be provided.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings.

[1. Constitution〕
In this embodiment, a navigation device that guides a route to a destination (hereinafter referred to as “this device”) will be described. It can also be grasped as a control method and a control program. The configuration of this device is shown in FIG. Shown in

  That is, 1 is an FM multiplex reception and processing unit for acquiring VICS information, and 2 is a beacon reception and processing unit for acquiring VICS information. Here, the road traffic information communication system center generally divides the area into service areas (secondary meshes) of about 10 km × 10 km, and traffic information of each mesh is transmitted in order, and this is received as an FM multiple reception and processing unit. 1 or beacon reception and processing unit 2 will receive. The traffic information for each mesh includes (1) the link travel time of each link in the mesh, (2) the degree of traffic congestion of each link in the mesh (by three categories: traffic jam, congestion, and smooth), (3) within the mesh The link type (intercity expressway, intracity expressway, general road) of each link is included.

  Reference numeral 3 denotes a main CPU (central processing unit) that controls the entire system and its peripheral circuits, and is a control unit that performs information processing including control of each part of the apparatus. 4 is a dynamic RAM (DRAM) for loading the main program, 5 is a static RAM (SRAM) with battery backup for holding memory contents such as settings while the main power is off, 6 Is a ROM that is accessed by the control unit 3 at the time of startup or the like.

  Reference numeral 7 denotes a display unit for drawing and displaying information such as a map, and has a display screen such as a liquid crystal display panel. Reference numeral 8 denotes a video RAM (VRAM) provided for the display unit 7. 9 is a TV reception and processing unit for receiving TV (various television broadcasts), and 10 is a vehicle information acquisition unit that detects operations and states such as illumination (lighting of instrument panels, etc.), vehicle speed pulses, and parking. It is.

  11 records road map data (typically, route search data and map display data), other search data, map-related data, and the like using a drive such as an HDD, DVD-ROM, or CD-ROM. This is a map data storage device.

  12 is an input unit that receives input of information and operations, and is a control device that detects an input from a touch key or the like. However, the configuration and type of the input unit are arbitrary, in addition to the operation switches around the display unit 7, A remote control unit, a touch sensor integrated with a display panel, or the like may be used alone or in combination. Reference numeral 15 denotes a positioning unit that obtains navigation information relating to the behavior of the host vehicle such as the current position, direction, and speed by using a positioning technique (for example, GPS, gyroscope, geomagnetic sensor, acceleration sensor, vehicle speed pulse).

  Moreover, the control part 3 implement | achieves and performs the process means (30, 31 ... shown in FIG. 1) corresponding to the following functions and an effect | action by a predetermined control program. Note that navigation processing common to the past (for example, destination designation reception, route search, guidance guidance output, etc.) is not an element peculiar to the present invention except for the guidance point output. Omitted.

[2. Effect)
[2-1. (Overview)
In this embodiment, first, the VICS information is received from the FM multiplex reception and processing unit 1 and the beacon reception and processing unit 2, and the road traffic information reception unit 31 stores the VICS information in the main memory M. Here, VICS provides the required time (link travel time) for passing the link in addition to the degree of congestion of the link as described above.

  More specifically, the VICS information from the road traffic information communication system center is provided as traffic congestion information of each mesh by dividing the area into service areas (secondary meshes) of about 10 km × 10 km. And as described above, the traffic information for each mesh includes (1) the link travel time for each link in the mesh, and (2) the traffic congestion level for each link in the mesh (separated into three categories: traffic jam, congestion, and smooth). (3) It includes information such as the link type (intercity expressway, intracity expressway, general road) of each link in the mesh.

  Therefore, the road traffic information analysis unit 32 extracts only the link travel time from the VICS information, and reads the link length corresponding to the link travel time from the map database stored in the storage device 11. Then, the average transit time of the link is calculated from the link length corresponding to the link travel time information.

Based on this calculation result, the congestion degree calculation unit 33 calculates an average passing time for each link, and calculates the congestion degree by finely classifying it. The classification by the congestion degree calculation unit 33 can be expressed in, for example, five levels as shown in FIG. 3 and the following.
(1) Traffic jam 1: 5km / h or less for ordinary roads, 10km / h or less for urban highways, and 20km / h or less for intercity highways
(2) Traffic jam 2: 5 to 10km / h for general roads, 10 to 20km / h for urban highways, 20 to 40km / h for intercity highways
(3) Congestion: 10-20km / h for general roads, 20-40km / h for urban highways, 40-60km / h for intercity highways
(4) Smooth 1: General road 20-30km / h, urban highway 40-60km / h, intercity highway 60-80km / h
(5) Success 2: General road is 30km / h or more, urban highway is 60km / h or more, intercity highway is 80km / h or more

Next, the display control unit 34 changes the display mode and displays the traffic congestion levels (1) to (5) on the map screen. Here, as an example of this display mode, the normal VICS traffic information display is based on “red” for congestion, “yellow” for congestion, and “green” for smooth traffic. Colors can be assigned and displayed as follows.
(1) Traffic jam 1: Red line with black frame
(2) Traffic jam 2: Red line
(3) Congestion: Orange line
(4) Normal 1: Green line
(5) Success 2: Green line with black frame

  In this way, for the three categories (2) to (4), the color scheme is the same as the traffic information provided in the past, and the traffic congestion level is higher than that (1) “Congestion 1” and the highest traffic congestion level. Low (5) For “smooth 2”, the middle three categories are the display modes changed. Note that such a display mode is merely an example, and any mode may be used as long as the user can recognize the degree of congestion. For example, it is also possible to configure the highest color (1) and the lowest traffic level (5) with “black lines” instead of (2) or (4) with the same color “wave line”. .

  In the present embodiment as described above, the road traffic information analysis unit 32 reads the link length of the link in the map database based on the link travel time information obtained from the VICS information, and calculates the average transit time of each link from here. calculate. Next, the congestion degree calculation unit 33 obtains the link passing speed based on the average passage time for each link from the calculation result, and obtains the congestion degree by finely classifying this. In accordance with the degree of traffic congestion, the display control unit 34 displays each of the traffic congestion degrees (1) to (5) on the map screen while changing the display mode.

  In this way, the traffic congestion degree that has been divided into three categories in the past is divided into smaller categories such as five categories as shown in this embodiment, for example, thereby providing more detailed traffic information according to the traffic speed. Can do.

[2-2. Example of processing procedure)
An example of the processing procedure in the present embodiment as described above is shown in the flowchart of FIG. In this example, first, the road traffic information receiving unit 31 receives from the VICS via the FM multiplex reception and processing unit 1 and the beacon reception and processing unit 2 and stores them in the main memory M (STEP 1). Next, the road traffic information analysis unit 32 extracts only the link travel time information from the VICS information, and based on the link travel time information, calculates the link length of the link in the map database stored in the storage device 11. The average transit time of the link is calculated from the read and the link length corresponding to this link travel time information (STEP 2).

  The congestion degree calculation unit 33 calculates the average passing speed of the link using the link travel time and the link length read from the map database, and divides the value to obtain a five-stage congestion degree (STEP 3). Specifically, the average passing speed is calculated from the formula “average passing speed = link length / link travel time”, and the degree of congestion is assigned from the average passing speed−congestion degree conversion table of FIG.

  This process is repeated until the congestion level for all links on the route is calculated (NO in STEP 4). When the congestion level data for all links is calculated (YES), the data is transferred to the display control unit 34. . Based on this traffic jam level, the display control unit 34 displays a traffic jam level line on the display unit 7 in association with the display mode for each traffic jam level (STEP 5), and ends the process (END).

[3. Other embodiments]
In addition, this invention is not limited to the said embodiment, The following example and another example are included. For example, since the configurations, processing procedures, examples, and the like shown in the above embodiment are schematic examples, they can be embodied or changed as appropriate. For example, in the above embodiment, three types of traffic information (link travel time, link traffic level, link type) obtained from VICS information are listed, and the traffic level is calculated using only the link travel time. . The present invention is not limited to such a mode, and as shown in FIG. 4, in addition to the configuration of the above embodiment, a congestion degree determination unit 35 is provided. Here, the congestion for each link obtained by the congestion degree calculation unit 33 is provided. It is also possible to compare the degree of “link congestion degree” with respect to all links in the congestion information obtained from the VICS information.

  The flow of processing in this case is as shown in FIG. 5, but STEP 1 to STEP 4 are the same as the processing of the above-described embodiment shown in FIG. 2, so the processing after STEP 5 will be described. That is, the congestion degree determination unit 35 checks whether or not the congestion degree for each link on the route calculated by the congestion degree calculation unit 33 matches the congestion degree of each link obtained from the VICS information (STEP 5 ).

  In this case, as described above, the congestion degree obtained from the VICS information is divided into three stages, whereas the congestion degree calculated by the congestion degree calculation unit 33 is five stages. As shown in the figure, each of the “congestion 1” and “congestion 2” of the congestion degree calculated by the congestion degree calculation unit 33 is “congestion” of the congestion degree obtained from the VICS information, and “smooth 1” and “smooth 2”. Each of “” is “smooth” and “congestion” is checked to see if it matches “congestion” as it is.

  If the congestion degree calculated by the congestion degree calculation unit 33 matches the congestion degree obtained from the VICS information (YES in STEP 5), the congestion degree calculated by the congestion degree calculation unit 33 is displayed and controlled. The display control unit 34 displays a traffic congestion level line on the display unit 7 in association with the display mode for each traffic congestion level based on the traffic congestion level (STEP 6), and ends the processing (END).

  On the other hand, when the congestion level calculated by the congestion level calculation unit 33 and the congestion level calculated by the congestion level calculation unit 33 do not match (NO in STEP 5), the congestion level determination unit 35 obtains from the VICS information. The displayed traffic congestion level is handed over to the display control unit 34, and the display control unit 34 displays a traffic congestion level line on the display unit 7 in association with the display mode for each traffic congestion level based on the traffic congestion level (STEP 7) and ends the processing. (END).

  In this case, the congestion degree calculated by the congestion degree calculation unit 33 and the congestion degree obtained from the VICS information are checked for coincidence and mismatch for each link, and only the matching links are calculated by the congestion degree calculation unit 33. It is also possible to display the traffic congestion degree obtained, and for the links that do not match, the traffic congestion degree obtained from the VICS information can be displayed.

  By such processing of the traffic jam level determination unit, it is possible to provide more accurate traffic jam information to the user.

The functional block diagram which shows the structure of embodiment of this invention. The flowchart which shows the process in embodiment of this invention. The table | surface which shows the classification of the congestion degree in embodiment of this invention. The functional block diagram which shows the structure of other embodiment of this invention. The flowchart which shows the process in other embodiment of this invention. The conceptual diagram which shows an example of the congestion degree determination process in other embodiment of this invention. The table | surface which shows the classification of the congestion degree obtained from VICS information.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... FM multiplex reception and processing part 2 ... Beacon reception and processing part 3 ... Control part (Main CPU and its peripheral circuit)
DESCRIPTION OF SYMBOLS 30 ... Navigation part 31 ... Road traffic information receiving part 32 ... Road traffic information analysis part 33 ... Congestion degree calculation part 34 ... Display control part 35 ... Congestion degree determination part 4 ... Dynamic RAM (DRAM)
5. Static RAM (SRAM)
6 ... ROM
7 ... Display 8 ... Video RAM (VRAM)
DESCRIPTION OF SYMBOLS 9 ... TV reception and processing part 10 ... Vehicle information acquisition part 11 ... Storage device 12 of road map data / search data and map related data ... Input part (touch key control device)
15 ... Positioning part M ... Main memory

Claims (9)

In a navigation device comprising a storage unit for storing road map data for route search and map display and facility data including the location of the facility, and a display unit for displaying information,
Receiving means for receiving road traffic information obtained from outside the vehicle;
The road traffic information includes at least a link travel time, the link length of the link corresponding to the link travel time received by the receiving means is read from the road map data, and the link travel time and the link length Road traffic information analysis means for calculating the average transit time of the link;
Congestion level determination means for determining multiple levels of traffic congestion based on this average transit time;
Display control means for outputting to the display unit so that it can be distinguished for each congestion degree;
A navigation device characterized by comprising:   2. The navigation apparatus according to claim 1, wherein the congestion degree determining means determines the congestion degree into five stages of congestion 1, congestion 2, congestion, smooth 1, and smooth 2. The road traffic information includes congestion degree information,
Congestion degree determination means for determining a difference between the congestion degree determined by the congestion degree determination means and the congestion degree obtained from the road traffic information,
The display control means is determined by the congestion degree determination means when the congestion degree determined by the congestion degree determination means matches the congestion degree obtained from the road traffic information by the congestion degree determination means. The traffic congestion degree obtained is output to the display unit, and when the traffic congestion degree obtained from the road traffic information does not match, the traffic congestion degree obtained from the road traffic information is output to the display unit. The navigation device according to claim 1 or 2. In a control method of a navigation device comprising a storage unit that stores road map data for route search and map display and facility data including the location of the facility in advance, and a display unit for displaying information,
Processing to receive road traffic information obtained from outside the vehicle;
The road traffic information includes at least a link travel time, the link length of the link corresponding to the link travel time received by the receiving means is read from the road map data, and the link travel time and the link length Road traffic information analysis processing to calculate the average transit time of the link,
Congestion level determination processing that determines multiple levels of traffic congestion based on this average transit time,
Display control processing to output to the display unit so that it can be distinguished for each congestion degree;
The control method of the navigation apparatus, wherein the control unit or the computer executes.   5. The method of controlling a navigation device according to claim 4, wherein the congestion degree determination process includes a process of determining the congestion degree in five stages of congestion 1, congestion 2, congestion, smooth 1, and smooth 2. The road traffic information includes congestion degree information,
A congestion degree determination process for determining a difference between the congestion degree determined by the congestion degree determination process and the congestion degree obtained from the road traffic information,
The display control process is determined by the congestion degree determination process when the congestion degree determined by the congestion degree determination process matches the congestion degree obtained from the road traffic information by the congestion degree determination process. A process of outputting the traffic congestion degree obtained from the road traffic information to the display unit when the traffic congestion degree obtained from the road traffic information does not coincide with the traffic congestion degree obtained from the road traffic information. The method for controlling a navigation device according to claim 4 or 5, characterized in that: In a control program for a navigation device comprising a storage unit for storing road map data for route search and map display and facility data including the location of the facility in advance, and a display unit for displaying information,
This program
A reception process for receiving road traffic information obtained from outside the vehicle;
The road traffic information includes at least a link travel time, and the link length of the link corresponding to the link travel time received by the receiving unit is read from the road map data, and the link travel time and the link length Road traffic information analysis processing to calculate the average transit time of the link from
Congestion level determination processing that determines multiple levels of traffic congestion based on this average transit time,
Display control processing to be output to the display unit so that it can be distinguished for each congestion degree;
A control program for a navigation device, which causes a computer or a control unit to execute.   8. The control of a navigation device according to claim 7, wherein the processing for determining the degree of traffic congestion is to determine the traffic congestion level in five stages of traffic jam 1, traffic jam 2, congestion, smooth 1 and smooth 2. program. The road traffic information includes congestion degree information,
A congestion degree determination process for determining a difference between the congestion degree determined by the process for determining the congestion degree and the congestion degree obtained from the road traffic information,
The display control process is determined by the congestion degree determination process when the congestion degree determined by the congestion degree determination process matches the congestion degree obtained from the road traffic information by the congestion degree determination process. If the traffic congestion degree obtained from the road traffic information does not match the traffic congestion degree obtained from the road traffic information, the traffic congestion degree obtained from the road traffic information is output to the display unit. 9. The control program for a navigation device according to claim 7,