JP2006275673A - Navigation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide "a navigation system" displaying presumed positions of other vehicles on a map, when no information on the positions of the other vehicles can be received. <P>SOLUTION: The navigation system displays the position M of a vehicle on which the system is attached and the positions T of the other vehicles on a map. When receiving no information on the positions of the other vehicles via a communication means, the positions of the other vehicles are presumed and these are displayed on a map, on the basis of information on their courses up to destinations in information received in the past, elapsed time when reception is disabled, and estimated vehicle speeds of the other vehicles. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a navigation device that searches for a route to a destination and guides the searched route, and particularly relates to a function of displaying the position of another vehicle on a display map.

  The navigation system detects the current position of the vehicle, reads out map data around the vehicle position from the map database, draws it on the display, displays the vehicle mark on the map, and changes the vehicle position. Then, the map is scrolled accordingly, and the road to the destination is guided.

  In recent years, navigation devices with communication functions have been put into practical use, and it is possible to obtain real-time location information of other vehicles, road / traffic information, etc. using a network or inter-vehicle communication, etc. It is possible to obtain updated data.

  For example, Patent Literature 1 discloses a navigation device that displays a position of another vehicle on a display using a communication function. In this navigation device, when the position information of another vehicle cannot be received, the display form is changed by changing the color or shape of the other vehicle position mark or blinking the other vehicle position mark. It is possible to display the elapsed time from the reception time of the previous other vehicle position information, or to display the travel locus of the other vehicle.

JP-A-9-210698

  When displaying the position of another vehicle on the navigation device, if you travel in an area where communication is impossible or where the reception of radio waves is poor, you will not be able to receive other vehicle position information and you can display the position of the other vehicle on the map. Disappear. In such a case, in Patent Document 1, the display form of the other vehicle position is changed, or the elapsed time from the last received time is displayed, thereby presenting the wrong other vehicle position information to the user. I try not to. However, when the reception is recovered, the position of the other vehicle may be far away from the previous reception, and it may be difficult for the user to cope with the sudden change of the position of the other vehicle on the map. Furthermore, if the amount of movement of the other vehicle position is too large, it cannot be displayed on the map scale of the display, and when the reception is restored, the display of the other vehicle position may disappear from the map.

  SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a navigation device that solves the above-described conventional problems and can display an estimated position of another vehicle on a map when other vehicle position information cannot be received.

  An electronic device having a navigation function capable of displaying a position of a host vehicle and a position of another vehicle on a map according to the present invention, a display for displaying a map, a position of the host vehicle, a position of the other vehicle, etc. Enabling communication means, receiving means for receiving other vehicle position information via the communication means, and when no other vehicle position information can be received, the other vehicle based on the other vehicle position information received in the past at least Other vehicle position estimating means for estimating the position, and display control means for displaying the estimated other vehicle position on a map of the display are provided.

  Preferably, the other vehicle position information includes guidance route information to the destination of the other vehicle, and the other vehicle position estimation means includes the guidance route information of the other vehicle, an elapsed time since the reception is disabled, and the other vehicle. The other vehicle position is estimated based on the estimated vehicle speed. The expected vehicle speed can be calculated with reference to the type of road on which the other vehicle travels, the road traffic situation, the weather situation, the terrain situation, and the like.

  Further, the display control means may vary the map scale according to the estimated other vehicle position. Thereby, even when the estimated other vehicle position is away from the own vehicle position, both the own vehicle position and the other vehicle position can be displayed.

  The display control means may display so that the estimated position of the other vehicle can be identified as being in the estimated state. As a result, the user can recognize whether the position of the other vehicle is estimated or actually received. Furthermore, when starting the estimation of the position of the other vehicle and correcting the estimated position of the other vehicle, it is also possible to notify that fact. Thereby, the user can recognize the estimation start time and the estimation end time of the other vehicle position.

  According to the electronic device equipped with the navigation function of the present invention, when the reception is impossible or difficult, the other vehicle position is estimated, and the estimated other vehicle position is displayed on the map. The user can recognize the area where the other vehicle is traveling. Furthermore, even when the reception is resumed, the position of the other vehicle can be corrected and displayed smoothly without a sense of incongruity.

  The best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram illustrating a configuration of an in-vehicle navigation system 1 according to the present embodiment. The GPS receiver 10 receives radio waves from GPS satellites and measures the current position and current direction of the vehicle. The self-contained navigation sensor 12 detects a vehicle speed sensor that detects a moving distance of the vehicle and a rotation angle of the vehicle. The VICS / FM multiple receiver 16 sequentially receives current road traffic information outside the vehicle via the antenna 14. The user input interface 20 includes an operation panel 22, a voice input unit 24, and a remote control operation unit 26, and transmits these inputs to the navigation device 1. The operation panel 20 includes a touch panel of the display 52, for example.

  The storage device 30 is preferably composed of a large capacity hard disk drive (HDD). The hard disk stores a program and a database for executing various navigation functions. The database includes map data and facility data, and the map data includes road link data and intersection data. The link data is data relating to a road connecting the intersection and the intersection data, and includes node data indicating the coordinates of the start point and the end point of the road and type data indicating the type of road (national road, ordinary road, prefectural road, etc.).

  The data communication control unit 32 enables network communication to a server or the like or vehicle-to-vehicle communication. This communication may be built in the navigation device or may be an external connection of a communication terminal such as a mobile phone. In the present embodiment, the other vehicle position information is received or the own vehicle position information is transmitted to the other vehicle by inter-vehicle communication or network communication.

  The voice output unit 40 includes a speaker 42 and outputs, for example, voice such as intersection guidance when guiding a route. The display control unit 50 is connected to the display 52 and displays map data and the like read from the storage device 30 or the data memory 70 on the display 52. In addition, the vehicle mark indicating the current position of the vehicle, the route to the destination, the guidance display of the intersection, or the landmark is synthesized and displayed on the map.

  The program memory 60 stores various programs executed in the navigation device 1, and the control unit 80 operates according to these programs. The program memory 60 may store a program in advance or may load a program from the storage device 30. The program memory 60 includes, for example, a program 62 for searching for a route to the destination, a program 64 for guiding the searched route, a program 66 for acquiring other vehicle position information and displaying the position of the other vehicle, and unreceivable Alternatively, it includes a program 68 that estimates the position of the other vehicle when it is difficult to receive and corrects the estimated position of the other vehicle based on the information on the position of the other vehicle reacquired when the reception is resumed.

  The data memory 70 includes processing results of various operations processed by the control unit 80, map data 72 read from the storage device 30, guidance route data 74 to the destination, and other vehicles acquired from the data communication control unit 32. Temporary storage of the predicted vehicle speed and elapsed time 78 of other vehicles calculated when the position information 76 and other vehicle position information cannot be received is temporarily stored. The data memory 70 can be a DRAM, SRAM, flash memory or the like, and the contents of the data memory 70 may be transferred to the storage device 30. Further, an external memory that can be attached to the navigation device 1 may be used in combination with the data memory 70.

  Next, a preferred operation example when displaying the position of another vehicle in the navigation device will be described. First, when the destination is set by the user in the own vehicle, the control unit 80 searches for a guidance route to the destination and starts route guidance (step S101). Next, the control unit 80 displays whether or not to display the position of the other vehicle on the display 52 or outputs it by voice, and in response to this, the user inputs an indication to display the position of the other vehicle. (Step S102), the control unit 80 checks whether data communication is possible by the data communication control unit 32 (Step S103). When the radio wave reception sensitivity is below a certain level, or in the case of inter-vehicle communication, it is determined that communication is not possible when there is no other vehicle within the communicable range from the own vehicle.

  When it is determined that data communication is possible, the control unit 80 receives the other vehicle position information via the data communication control unit 32 (step S104). The target other vehicle may be registered in advance by user setting, or may be appropriately specified according to an instruction from the user. In addition, as long as the vehicle-to-vehicle communication is used, it may be all other vehicles that are within a communicable range from the own vehicle, or may be another vehicle specified by the user. Here, the other vehicle position information includes latitude, longitude, speed at which the other vehicle is currently traveling, guidance route information to the destination, and the like. The other vehicle position information received via the data communication control unit 32 is stored in the data memory 70 (step S105).

  As shown in FIG. 3, the control unit 80 displays the host vehicle position mark M on the map of the display 52 and displays the other vehicle position mark T based on the received other vehicle position information. The reception of other vehicle position information is performed at regular time intervals, and each time it is confirmed whether the reception state is good (step S107). If the reception state is good, the other vehicle position information is continuously received, the stored other vehicle position information is updated, and the change of the other vehicle position T is displayed on the display (steps S104 to S106).

  On the other hand, if it is determined that the other vehicle position information cannot be received or is difficult to receive (step S107), the control unit 80 starts estimating the other vehicle position (step S108). The control unit 80 estimates the position of the other vehicle based on the guidance route information to the destination included in the other vehicle position information received immediately before, the predicted vehicle speed of the other vehicle, and the elapsed time from the point of time when reception becomes impossible. At this time, the control unit 80 can provide voice guidance from the speaker 42 that the estimation of the position of the other vehicle is started, or can display that effect on the display 52. Thereby, the user can recognize that it switched to the other vehicle position estimated from the display of the actual other vehicle position.

  The predicted vehicle speed of the other vehicle can be calculated based on road type information on which the other vehicle is traveling, terrain status, weather information, road traffic information, and the vehicle speed of the other vehicle received immediately before. The road type is a type such as an expressway or a national road. For example, the speed can be set in advance to 80 km if the road on which the other vehicle is traveling is an expressway, 60 km if it is a national road, and 40 km if it is a prefectural road or a city road. Alternatively, the speed limit set on the road (link) may be used.

  The terrain situation is information on the terrain of the road. For example, if the running road is at an altitude of 500 meters or more, it is determined that the road is a mountain road with many curves, ups and downs, and a predetermined speed is set so that the vehicle speed is lower than that on other plains. You may make it multiply by a coefficient (for example, 0.8).

  For example, when it is snowing or raining according to the weather information, the speed is expected to be slow, so a coefficient that reduces the vehicle speed is multiplied. Further, the road traffic information is multiplied by a coefficient that reduces the vehicle speed even when an accident or failure exists on the travel route. Furthermore, the vehicle speed of the other vehicle received immediately before may be referred to.

  The controller 80 calculates the travel distance of the other vehicle from the product of the elapsed time and the predicted vehicle speed on the road specified by the guide route information to the destination of the other vehicle, and estimates the position of the other vehicle. For example, as shown in FIG. 3, when the last acquisition point of the other vehicle position information is the point A, a position or locus (broken line) estimated on the guidance route based on the calculated moving distance is displayed (step). S109). The display of the estimated other vehicle position may be performed every predetermined period, or may be performed every time the moving distance exceeds a certain value. Furthermore, the color of the other vehicle position mark T may be changed, blinked, or the shape may be changed so that the user can easily recognize the estimated position of the other vehicle. Good.

  In parallel with the estimation of the position of the other vehicle, the controller 80 checks whether or not the reception state has been recovered (step S110). When the reception state is restored, a message to that effect is displayed on the voice guidance or display to inform the user that the estimation of the position of the other vehicle has been completed.

  When the reception state is recovered, the control unit 80 reacquires other vehicle position information, compares the reacquired other vehicle position information with the estimated other vehicle position, and corrects the difference (step S111). As shown in FIG. 3, if the other vehicle position estimated last is the point B and the other vehicle position based on the re-obtained other vehicle position information is the C point, the difference S is corrected, and the C point The other vehicle position mark is moved and displayed (step S112).

  When the other vehicle position display is not desired by the user or when communication is not possible, the other vehicle position display is not performed, and when there is an instruction from the user to end the other vehicle position display (step S113), The other vehicle position display ends. There may be a plurality of other vehicle positions to be displayed. In this case, the same display is performed for each other vehicle position.

  Next, a second embodiment of the present invention will be described. When the other vehicle position is estimated and displayed, the estimated other vehicle position is far away from the own vehicle position, and there is a possibility that it cannot be displayed on the current map scale on the display. Therefore, in the second embodiment, automatic switching of the map scale is enabled. FIG. 4 is a diagram showing an operation flow of automatic map scale switching.

  First, the control unit 80 reads a map scale set in the display 52 from a data memory or the like (step S201), and calculates a displayable area on the display when the vehicle position is used as a reference (step S202). For example, as shown in FIG. 5, the coordinate point A1 (x1, y1), the coordinate point A2 (x2, y2), the coordinate of each corner of the displayable area based on the coordinate M (xm, ym) of the vehicle position A point A3 (x3, y3) and a coordinate point A4 (x4, y4) are calculated.

  Next, the control unit 80 compares the estimated coordinates T (xt, yt) of the other vehicle position with the displayable area surrounded by the coordinates A1, A2, A3, A4 of the displayable area (step S203). Then, it is determined whether or not the estimated coordinates of the other vehicle position are included in the displayable area (step S204). When it is determined that it is not included, the next largest map scale is read from the data memory (step S205), the coordinate points B1, B2, B3, B4 of the displayable area are calculated again and compared with the estimated coordinates of the other vehicle position. Then, it is determined whether or not the estimated other vehicle position is included in the displayable area (step S207). This operation is repeated, and the map scale N determined to include the estimated coordinates of the other vehicle position is set (step S208). As a result, the display control unit 50 displays the map on the map scale N and displays the map on the map. The own vehicle position and the other vehicle position are displayed (step S209).

  By automatically switching the map scale in this way, when the estimated other vehicle position is corrected to the actual position, the map scale is prevented from being suddenly switched, and the map screen is easy to see for the user.

  Next, a third embodiment of the present invention will be described. In the third embodiment, the display of the other vehicle position is varied according to the communication state. For example, as shown in FIG. 6, the host vehicle 200 accesses the server 210 via network communication, provides the host vehicle position information to the server 210, and receives other vehicle position information from the server 210. Similarly, the other vehicle 300 transmits / receives position information to the server 210 via network communication.

  Here, when the other vehicle position information cannot be received, the control unit 80 determines whether it is a failure in the communication state between the host vehicle 200 and the server 210 or a failure between the other vehicle 300 and the server 210. For example, when the other vehicle position information cannot be received within a certain time even though the reception state of the vehicle's radio wave is good, it is determined that there is a failure in the communication state between the server 210 and the other vehicle 300. On the other hand, when the radio wave state of the own vehicle is bad, it is determined that the communication state between the own vehicle 200 and the server 210 is faulty.

  The control unit 80 identifies and displays the other vehicle position estimated according to the cause location where the reception is impossible. For example, if the cause is a communication failure between the host vehicle and the server, the other vehicle position mark is displayed in blue, and if the cause is a communication failure between the other vehicle and the server, the other vehicle position mark is displayed in red. Of course, in addition to changing the color, the display form and the like can be changed.

  Thereby, the user can recognize immediately the cause location which became impossible to receive by looking at the other vehicle position mark.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Deformation / change is possible.

  The navigation device according to the present invention is used in a vehicle-mounted navigation device or a computer device having a navigation function. Further, the navigation device may be a composite electronic device including an audio function, a video function, and the like.

It is a block diagram which shows the structure of the navigation system which concerns on the Example of this invention. It is a flowchart explaining operation | movement of the navigation system of a present Example. It is a figure which shows the example of a display of an other vehicle position. It is a flow which shows the map scale automatic switching operation | movement in the case of the other vehicle position display which concerns on 2nd Example of this invention. It is a figure explaining the displayable area | region of a display. It is a figure explaining the 3rd Example of the present invention.

Explanation of symbols

1: Navigation device 10: GPS receiver 20: User input interface 30: Storage device 32: Communication control unit 40: Audio output unit 50: Display control unit 52: Display 60: Program memory 70: Data memory

Claims (13)

An electronic device having a navigation function capable of displaying the position of the host vehicle and the position of another vehicle on a map,
A display for displaying a map and the like;
A communication means that enables data transmission and reception with the outside;
Receiving means for receiving other vehicle position information via communication means;
When it is no longer possible to receive other vehicle position information, at least other vehicle position estimation means for estimating the other vehicle position based on the other vehicle position information received in the past,
Display control means for displaying the estimated position of the other vehicle on the map of the display;
An electronic device. The electronic device according to claim 1, wherein the other vehicle position information includes guide route information to a destination of the other vehicle. The electronic device according to claim 1, wherein the other vehicle position estimation means estimates the position of the other vehicle based on guidance route information of the other vehicle, an elapsed time from when reception is disabled, and an expected vehicle speed of the other vehicle. . The electronic device according to claim 3, wherein the predicted vehicle speed is calculated according to a road type on which another vehicle travels. The electronic device according to claim 4, wherein the predicted vehicle speed is calculated based on road traffic conditions, weather conditions, or terrain conditions. The electronic device according to claim 1, wherein the display control unit varies the map scale according to the estimated other vehicle position. The electronic device according to claim 1, wherein the display control means displays so that the estimated position of the other vehicle can be identified. The electronic device further includes a correcting unit that corrects the estimated position of the other vehicle based on the re-obtained other vehicle position information when the other vehicle position information is re-obtained by resuming reception. The electronic device according to claim 1, wherein the displayed position of the other vehicle is displayed on a map. The electronic device further includes a discriminating unit for discriminating whether the cause location where the other vehicle position information cannot be received is on the own vehicle side or the other vehicle side, and the display control unit determines whether the cause location is based on the discrimination result. The electronic device according to claim 1, wherein the position of another vehicle is identified and displayed so as to be identified. The electronic device according to claim 1, further comprising notification means for notifying when the estimation of the position of the other vehicle is started and when the estimated position of the other vehicle is corrected. A method for displaying the position of another vehicle in a navigation device capable of displaying the position of the host vehicle and the position of the other vehicle on a map,
Receiving other vehicle position information via communication means;
Displaying the other vehicle position on a map of the display based on the received other vehicle position information;
Estimating other vehicle position based on other vehicle position information received in the past when it becomes impossible to receive other vehicle position information;
Displaying the estimated position of the other vehicle on the map;
Display method of other vehicle position including The step of estimating the position of the other vehicle estimates the position of the other vehicle based on information on a guide route to the destination of the other vehicle, an elapsed time since the reception is disabled, and an expected vehicle speed of the other vehicle. The display method of the other vehicle position described. The display method of the other vehicle position according to claim 11, further comprising a step of correcting the other vehicle position estimated based on the other vehicle position information reacquired by resuming reception.

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