JP3498542B2 - Vehicle route guidance system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle route guidance system for performing data communication between a vehicle and an external center using a telephone line.

[0002]

2. Description of the Related Art Conventionally, as a route guidance system for a vehicle for performing data communication between a vehicle and an external center using a telephone line, there is known a "wireless guidance type navigation system" described in JP-A-2-79200. Has been. In this system, the vehicle position data and the destination position data are transmitted from the vehicle-mounted device to the external center, and the guidance information obtained by calculating the route at the external center is returned to the vehicle-mounted device.

[0003]

However, in such a conventional "wireless navigation system", the route calculation is performed on the vehicle side depending on the distance between the vehicle position data and the destination position data. In some cases, a large amount of communication time was required on the external center side.
The present invention has been made in view of the above, and an object thereof is to provide a vehicle route guidance system that can quickly calculate a recommended route.

[0004]

The invention according to claim 1 is
In order to solve the above problems, a route guidance device provided on the vehicle side transmits a vehicle position and a destination position to an external center via a telephone line, and a route calculation device provided at the external center receives the received vehicle position. A route guidance system for a vehicle that returns route guidance information, which is the calculation result, to a route guidance device on the vehicle side after the route is calculated based on the destination position and the route guidance device on the vehicle side. Comparing the time required for route calculation with the time required for transmitting and receiving information between the vehicle side and the external center and the time required for route calculation at the external center The gist is to have a means and a device selecting means for selecting one of the devices that can not calculate the route in a shorter time based on the comparison result.

In order to solve the above-mentioned problems, the route guiding device provided on the vehicle side transmits the vehicle position and the destination position to an external center via a telephone line, and the route is transmitted to the external center. The route calculation device provided is a route guidance system for a vehicle that returns the route guidance information, which is the calculation result, to the route guidance device on the vehicle side after performing route calculation based on the received vehicle position and destination position. The route calculation device on the side of the external center, in contrast to the time required for route calculation on the vehicle side, the time required for transmitting and receiving information between the vehicle side and the external center and the route calculation on the side of the external center. And a time selecting means for comparing the time summed up with the time, and a device selecting means for selecting either one of the devices based on the comparison result so that the route can be calculated in a shorter time. And effect.

[0006]

According to the first aspect of the present invention, in the route guidance device on the vehicle side, information is transmitted and received between the vehicle side and the external center with respect to the time required for route calculation on the vehicle side. The time required for route calculation and the time required for route calculation on the external center side are compared, and based on the comparison result, it is possible to calculate the route in a shorter time. Since the recommended route is calculated in a shorter time, the recommended route can be promptly displayed on the vehicle side.

According to the second aspect of the present invention, in the route calculation device on the side of the external center, the information about the time required for route calculation on the side of the vehicle is provided between the side of the vehicle and the external center. Compare the time required for sending and receiving and the time required for route calculation at the external center side, and select either one of the devices that can not calculate the route in a shorter time based on this comparison result. Since the recommended route is calculated in a shorter time, the recommended route can be promptly displayed on the vehicle side.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a diagram showing a system configuration of a vehicle route guidance system according to a first embodiment of the present invention. As shown in FIG. 1, the vehicle side has a vehicle route guidance device 11, a communication adapter 13, and a telephone 15.

The vehicle route guidance device 11 is a device for calculating a recommended route from the vehicle position to the destination position and displaying it together with map information. The communication adapter 13 is arranged between the vehicle route guidance device 11 and the telephone 15, and is for performing data communication with an external center via a telephone line. On the other hand, the external center side has a telephone 21, a communication adapter 23, a route calculation unit 25, and a destination position search unit 27.
And have.

The route calculator 25 is a device for calculating a recommended route from the vehicle position to the destination position. When the driver of the vehicle obtains the information on the destination to some extent by using the telephone 21 from the driver of the vehicle to the operator of the external center, the destination position search unit 27 determines the destination position data based on the information on the destination. Is a data search device for searching for and acquiring.

FIG. 2 is a diagram showing a detailed structure of the vehicle route guide device 11 provided on the vehicle side. In the figure, a GPS (Global Positioning System) receiver 41
Is a receiver for measuring the current position and azimuth represented by latitude and longitude based on the radio waves from the satellite received via the antenna, and the current position data measured by the GPS receiver 41 is It is given to the system control unit 43.

The system control unit 43 has a timer for measuring time intervals, and controls the entire apparatus according to a predetermined control program stored in the ROM in the memory unit 45.
The ROM also stores an execution program corresponding to the navigation function, control data, and the like. The vehicle speed sensor 47 detects the traveling speed of the vehicle by generating a pulse signal corresponding to the rotation speed of the mission by a rotary encoder provided in the mission. Azimuth sensor 4
A built-in geomagnetic sensor or gyroscope 9 detects the azimuth angle.

The CD-ROM drive unit 51 is a CD-RO.
It has a drive mechanism that drives M, and the latitude and longitude recorded in the CD-ROM or a format corresponding to it (hereinafter,
It is a device that drives and reads map data that represents a position using map coordinates). The map data recorded in the CD-ROM drive device 51 is sent to the system control unit 43 using a transmission method such as serial communication or parallel communication.

The display control unit 53 exchanges image data between the system control unit 43 and the VRAM unit 55, draws the image data, stores the image data in the VRAM unit 55, and stores the image data in the VRAM unit 55. The image data is read at the display rate and displayed on the display unit 57. VRAM
The (Video Random Access Memory) unit 55 has a display unit 57.
Expand and store map data and traffic jam data that can be displayed in. The display unit 57 has a liquid crystal display panel or the like, and displays the display data created by the display control unit 53.

The screen touch panel unit 59 is a touch panel arranged on the screen of the display unit 57, and is a device for inputting position data when a contact is made in association with the position on the screen. The screen touch panel unit 59 inputs the touch of the fingertip of the operator as position data using a well-known electronic system, electrostatic system, optical system, or the like. Further, by displaying the operation guide information on the display unit 57 and touching a desired portion on the screen touch panel unit 59, for example, destination data necessary for route search is input.

Next, the operation of the vehicle route guidance system will be described with reference to the flow chart shown in FIG. In advance, the system control unit 7 reads the menu screen data for setting the destination from the memory unit 45, stores it in the VRAM unit 55 via the display control unit 53, and from the VRAM unit 55 via the display control unit 53. It is assumed that the menu screen data is read at the display rate and displayed on the display unit 57.
The display unit 57 displays touch switch images such as a destination setting switch, a guide information switch, and a navigation mode switch as a menu screen.

First, in step S10, the system control unit 43 acquires the vehicle position data measured by the GPS receiver 41 and the destination position data input via the screen touch panel unit 59. That is, the current position data detected by the GPS receiver 5 is loaded into the system control unit 7,
Next, the destination data designated by the operator via the screen touch panel unit 23 is loaded into the system control unit 7.

Next, in step S20, the system controller 43 calculates the distance (d) formed by the vehicle position data and the destination position data. Next, in step S30, the system control unit 43 calculates the vehicle-side required time (Tm) required when calculating the route on the vehicle side.

[0019]

Next, in step S40, the system control unit 43 calculates the time required for transmitting the vehicle position data and the destination position data from the vehicle side to the external center side, and the route calculation on the external center side. The time required for the center side (Tf) is calculated by summing the time required for the above and the time required for returning the data of the route calculation result to the vehicle side.

The time required for transmitting the vehicle position data and the destination position data from the vehicle side to the external center side and the time required for returning the route calculation result data to the vehicle side are added. The time taken may be considered as the time required for transmitting and receiving data between the vehicle side and the external center. On the external center side, a database structure optimized for route calculation will be used. The route calculation time at the external center side is 4 to 5 seconds or less at the maximum.

[0022] In step 50, the system control unit 43
Compares the calculated required time on the center side (Tf) with the calculated required time on the vehicle side (Tm), and determines whether or not Tf <Tm. As a result, when the vehicle-side required time (Tm) is longer than the center-side required time (Tf), the process proceeds to step S60. On the other hand, when the vehicle-side required time (Tm) is shorter than the center-side required time (Tf), the routine proceeds to step 80.

In step S60, the vehicle-side required time (T
When m) is larger, the vehicle position data and the destination position data are transmitted from the system control unit 43 to the external center side via the communication adapter 13 and the telephone 15 in order to perform the route calculation on the center side.

On the other hand, on the external center side, the vehicle position data and the destination position data are received by the route calculation section 25 via the telephone 21 and the communication adapter 23. In the route calculation unit 25,
The route from the vehicle position data to the destination position data is calculated using the database structure optimized for route calculation. For example, based on the well-known Dijkstra method, the nodes and road links recorded in this database are searched to create route data of the recommended traveling route. Next, the route calculation unit 25 on the external center side gives the route calculation result to the communication adapter 23 when the route calculation is completed.
It is transmitted to the vehicle side via the telephone 21.

Next, in step S70, the vehicle side sequentially stores the route calculation results received via the telephone 15 and the communication adapter 13 in the RAM of the memory unit 45. Also,
In step S80, when the vehicle-side required time (Tm) is shorter, the vehicle-side system control unit 43 calculates the route. That is, the system control unit 43 searches for a node or a road link recorded in the CD-ROM based on the vehicle position data and the destination position data based on the well-known Dijkstra method or the like to determine the recommended travel route. Create route data.

After that, the system control unit 43 expands and stores the route data in the VRAM unit 55 via the display control unit 53. Next, the map data corresponding to the wide area map that can display all the routes to the created destination is stored in the CD-ROM.
Wide area map data is read out from the CD-ROM via the drive unit 51 and expanded in the VRAM unit 55 via the display control unit 53. Next, the system control unit 43 controls the display control unit 5
The route data is overlaid on the map data stored in the VRAM unit 55 via 3 and read at the display rate to display the recommended route on the display unit 57.

In the present embodiment, the vehicle route guidance apparatus 11 on the vehicle side obtains the route calculation result, as compared with the conventional case where data is transmitted to the vehicle side after the route calculation is performed on the external center side. It is possible to reduce the time required up to about 8 seconds at the maximum. As described above, in the vehicle-side route guidance device 11, the vehicle position data and the destination position data are transmitted from the vehicle side to the external center side with respect to the vehicle-side required time (Tm) required to calculate the route on the vehicle side. Center-side required time (Tf), which is the sum of the time required for sending, the time required for route calculation at the external center side, and the time required for returning the route calculation result data to the vehicle side
Is calculated and compared, and based on this comparison result, it is possible to calculate the recommended route in a shorter time by selecting one of the devices that can not calculate the route in a shorter time. The recommended route can be displayed on the vehicle side.

(Second Embodiment) The second embodiment is applicable to the vehicle route guidance system according to the first embodiment shown in FIG. The operation of the vehicle route guidance system will be described below with reference to the flowchart shown in FIG.

First, in step S210, the route calculation unit 25 on the external center side acquires vehicle position data and destination position data from the vehicle route guidance device 11 provided on the vehicle side via a telephone line. That is, the current position data detected by the GPS receiver 5 of the vehicle route guiding apparatus 11 provided on the vehicle side is taken into the system control unit 7, and then specified by the operator via the screen touch panel unit 23. The destination data is taken into the system control unit 7, and then the vehicle position data and the destination position data are transmitted from the system control unit 43 to the external center side via the communication adapter 13 and the telephone 15.

On the other hand, on the external center side, the vehicle position data and the destination position data are received by the route calculation unit 25 via the telephone 21 and the communication adapter 23 and acquired. Next, in step S220, the route calculation unit 25 calculates the distance (d) between the acquired vehicle position data and the destination position data. Next, in step S230, the route calculation unit 25 calculates a vehicle-side required time (Tm) required when the route is calculated on the vehicle side.

Next, in step S240, the route calculation unit 25 calculates the time required for transmitting the vehicle position data and the destination position data from the vehicle side to the external center side and the route calculation on the external center side. The time required for the center side (Tf) is calculated by summing the time required for the above and the time required for returning the data of the route calculation result to the vehicle side. In addition,
Similar to the first embodiment, it is necessary to transmit the vehicle position data and the destination position data from the vehicle side to the external center side, and to return the route calculation result data to the vehicle side. The time obtained by adding the above time may be considered as the time required for transmitting and receiving data between the vehicle side and the external center.

Here, in step S250, the route calculator 25 compares the calculated required time on the center side (Tf) with the calculated required time on the vehicle side (Tm) to determine whether Tf <Tm. As a result, when the vehicle-side required time (Tm) is larger than the center-side required time (Tf), the process proceeds to step S260. On the other hand, when the vehicle-side required time (Tm) is shorter than the center-side required time (Tf), the process proceeds to step S280.

In step S260, if the vehicle-side required time (Tm) is longer, the route calculation unit 25 uses the database structure optimized for route calculation to reach the destination position data from the vehicle position data. Calculate the route. For example, based on the well-known Dijkstra method, the nodes and road links recorded in this database are searched to create route data of the recommended traveling route.

Next, in step S270, the route calculation unit 25 on the external center side transmits the route calculation result to the vehicle side via the communication adapter 23 and the telephone 21 when the route calculation is completed. On the other hand, the vehicle side sequentially stores the route calculation results received via the telephone 15 and the communication adapter 13 in the RAM of the memory unit 45.

In step S280, if the vehicle-side required time (Tm) is shorter, a route calculation request signal is sent to the communication adapter 23 and the telephone 21 so that the vehicle-side system control unit 43 can perform route calculation. To the vehicle side via.

Next, in step S290, the vehicle side
The route calculation is performed according to the route calculation request signal received via the telephone 15 and the communication adapter 13. That is, the system control unit 43 uses the CD-ROM based on the vehicle position data and the destination position data and the well-known Dijkstra method or the like.
The route data of the recommended traveling route is created by searching the nodes and road links recorded in.

After that, the system control unit 43 expands and stores the route data in the VRAM unit 55 via the display control unit 53. Next, the map data corresponding to the wide area map that can display all the routes to the created destination is stored in the CD-ROM.
Wide area map data is read out from the CD-ROM via the drive unit 51 and expanded in the VRAM unit 55 via the display control unit 53. Next, the system control unit 43 controls the display control unit 5
The route data is overlaid on the map data stored in the VRAM unit 55 via 3 and read at the display rate to display the recommended route on the display unit 57.

Even if the destination position data is not transmitted from the vehicle side, the driver of the vehicle calls the operator of the external center with some information regarding the destination 15
To transmit the destination position data based on the information of the destination by searching the destination position search unit 27 provided in the external center as shown in FIG. It goes without saying that the above procedure can be performed.

In this way, the route calculation unit 2 on the external center side
5, the time required for transmitting the vehicle position data and the destination position data from the vehicle side to the external center side with respect to the vehicle side required time (Tm) required for calculating the route on the vehicle side, and the external time The time required for calculating the route at the center side and the time required for returning the data of the route calculation result to the vehicle side are calculated and compared, and the result of this comparison is calculated. Based on the above, it is possible to calculate the recommended route in a shorter time by selecting one of the devices that can not calculate the route in a shorter time, so it is possible to quickly display the recommended route on the vehicle side. it can.

[Brief description of drawings]

FIG. 1 is a diagram showing a system configuration of a vehicle route guidance system according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a detailed configuration of a vehicle route guidance device 11 provided on the vehicle side.

FIG. 3 is a flowchart for explaining the operation of the vehicle route guidance system according to the first embodiment of the present invention.

FIG. 4 is a flowchart for explaining the operation of the vehicle route guidance system according to the second embodiment of the present invention.

[Explanation of symbols]

11 Vehicle route guidance device 13,23 Communication adapter 15,21 telephone 25 Route calculator 27 Destination location search section 41 GPS receiver 43 System control unit 45 memory section 47 vehicle speed sensor 49 Azimuth sensor 51 CD-ROM drive 53 Display control unit 55 VRAM section 57 Display 59 screen touch panel

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G01C 21/00 G08G 1/09 G08G 1/137 G09B 29/10

Claims (2)

(57) [Claims] 1. A route guidance device provided on the vehicle side transmits a vehicle position and a destination position to an external center via a telephone line, and a route calculation device provided at the external center receives the received vehicle position and purpose. A route guidance system for a vehicle, which returns route guidance information, which is a calculation result, to a route guidance device on a vehicle side after a route is calculated based on a ground position, and the route guidance device on the vehicle side is a route on the vehicle side. Time comparison means for comparing the time required for calculation with the time required for transmitting and receiving information between the vehicle side and the external center and the time required for route calculation at the external center side A route guidance system for a vehicle, comprising: a device selection unit that selects one of the devices that can calculate a route in a shorter time based on the comparison result. 2. A route guidance device provided on the vehicle side transmits a vehicle position and a destination position to an external center via a telephone line, and a route calculation device provided at the external center receives the received vehicle position and purpose. A route guidance system for vehicles that returns route guidance information, which is the calculation result, to a route guidance device on the vehicle side after the route calculation based on the ground position, wherein the route calculation device on the external center side is Time comparison means for comparing the time required for route calculation with the time required for transmitting / receiving information between the vehicle side and the external center and the time required for route calculation at the external center side A route guidance system for a vehicle, comprising: and a device selection means that selects one of the devices based on the comparison result so that the route can be calculated in a shorter time.