JP2009264829A - In-vehicle navigation system and map displaying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an "in-vehicle navigation system and map displaying method" which enable plain display for a user of route guidance at the start of running of a vehicle. <P>SOLUTION: The in-vehicle navigation system equipped with functions of searching for a guiding route to the destination and guiding the vehicle along the guiding route has a display means, a storage means wherein map data are stored, a driver's own vehicle location detecting means which detects the current location of a driver's own vehicle and a control means which makes the display means display on a screen a detailed map image which is formed, with a reduced scale adjusted, of a map of the area around the current location of the driver's own vehicle wherein the guiding route is shown, for a prescribed period from the start of the driver's own vehicle. The prescribed period may also be a period till a prescribed time passes, a period till the vehicle runs over a prescribed distance or a period till the vehicle runs along the guiding route. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an in-vehicle navigation device and a map display method for guiding a vehicle to a destination according to a guidance route, and more particularly to an in-vehicle navigation device and a map display method adapted to display an easy-to-understand map at the time of departure. .

  Conventional typical vehicle-mounted navigation devices include a control device such as a CPU that controls all processes related to navigation, a storage device such as a DVD (Digital Versatile Disk) -ROM or an IC memory card that stores map data in advance, It has a display device, a GPS (Global Positioning System) receiver, a detection device for detecting the current position and current direction of the vehicle, such as a gyroscope and a vehicle speed sensor. Then, the control device reads out map data including the current position of the vehicle from the storage device, displays a map image around the vehicle position on the display device screen based on the map data, and indicates the current position of the host vehicle. The vehicle position mark to be displayed is superimposed on the map image, and the map image is scrolled according to the movement of the vehicle, or the map image is fixed on the screen and the vehicle position mark is moved to show where the vehicle is currently located. You can see at a glance whether you are driving.

  In-vehicle navigation devices are usually equipped with a function (route guidance function) that guides the user so that the user can easily travel on the road without making a mistake. According to this route guidance function, the CPU calculates the optimal route from the departure point (typically the current position of the vehicle) to the destination using map data, such as a horizontal search method or a Dijkstra method. The route searched is stored as a guide route, and the route can be distinguished from other roads on the map image while traveling (for example, the color is changed or the line width is increased). When the vehicle approaches a predetermined distance to the intersection whose course should be changed on the guidance route, a guide map of the intersection on the map image (an enlarged view of the intersection, the direction of travel at the intersection) Display an arrow, a distance to the intersection, the name of the intersection, etc.) so that the user can know which road to drive and which direction to proceed at the intersection. It has become.

  When searching for a route, the user sets a destination in advance, and sets a waypoint on the way to the destination as necessary. If necessary, various conditions (whether toll road priority or general road priority) are also set. In the navigation device, a plurality of routes to the destination are searched based on these set data, and the searched routes are displayed in different colors, for example, according to one route selected by the user. Give guidance.

  In such a navigation device, the guidance route is displayed on the map in an easy-to-understand manner. However, even if the guidance route is searched, it is difficult to understand, or depending on the location, the guidance route is not searched and any road may be traveled. You may not know.

  An example where the guidance route is not searched is a road in a facility such as a golf course or a shopping mall. In general, the connection relationship between the roads inside the facilities and the roads outside the facilities is not grasped by the navigation device.

On the other hand, Patent Document 1 describes a navigation device that searches and guides a route from a vehicle position to a guidance route using map data in a facility.
JP 2005-37275 A

  As described above, in a region where a guidance route is not searched, if map data relating to the region can be acquired, a new route can be searched for guidance based on the map data.

  However, even when the guidance route is searched and displayed on the map, depending on the setting of the map scale, the driver may be misunderstood and the vehicle may be driven in the wrong direction. The map display scale can be switched to the detailed display when the vehicle is driven, but the map set in the wide area display is switched to the detailed display at the time of departure, and then the map is displayed at the scale set by the driver. To the driver, which is troublesome for the driver and may hinder safe driving.

  When a destination is set and a guidance route is searched and the vehicle is driven along the guidance route, intersections where the traveling direction is difficult to understand are enlarged and displayed in an easy-to-understand manner. However, the enlarged display of the map around the host vehicle is not performed when the vehicle is driven from the state where the engine is stopped after being parked or stopped.

  The present invention has been made in view of the problems of the prior art, and an object thereof is to provide an in-vehicle navigation device and a map display method capable of displaying easy-to-understand route guidance at the time of departure of vehicle travel. And

  In order to solve the above-described problems of the prior art, according to the basic form of the present invention, there is provided an in-vehicle navigation device having a function of searching for a guidance route to a destination and guiding the vehicle along the guidance route. Display means, storage means storing map data, own vehicle position detection means for detecting the current position of the own vehicle, and the guidance route is displayed for a predetermined period from when the own vehicle departs. There is provided a vehicle-mounted navigation device, comprising: a control unit that displays a detailed map image in which a scale of a map around the current position of the host vehicle is adjusted on a screen of the display unit.

  In the in-vehicle navigation device according to this aspect, the predetermined period is until the predetermined time has elapsed, until the own vehicle travels a predetermined distance, or until the own vehicle travels on the guidance route. You may make it either.

  Moreover, in the vehicle-mounted navigation device according to this aspect, the control means displays the detailed map image on the screen of the display means when a scaled map image according to a user instruction is displayed on the screen of the display means. The control means may divide the screen of the display means into two screens when one of the map images is displayed on the screen of the display means. The map image of the scale may be displayed, and the detailed map image may be displayed on the other screen. When the screen of the display unit is divided into two screens, the control unit displays the two screens. The detailed map image may be displayed on one screen, and the control means may display the details on one screen when the screen of the display means is divided into two screens. It may be caused to display the map image.

  Further, in the in-vehicle navigation device according to this aspect, the control means is configured to display the pre-departure screen on which a scale map image according to an instruction from the user is displayed on the screen of the display means when the predetermined period has elapsed. The control means may display the detailed map image with the scale adjusted when the scale of the map image displayed on the screen of the display means is a wide area display having a predetermined value or less. You may make it display on the screen of a means.

  According to the in-vehicle navigation device of the present invention, when a vehicle is departed, a detailed map is displayed only for a predetermined period after the departure when a map around the host vehicle is displayed with a smaller map than a predetermined scale value. Is displayed on the screen. For example, the wide area map has a scale of 200 m scale or less, and the detailed map displayed at the time of departure has a scale of 50 m scale, for example. Further, the predetermined period is a time after departure of the vehicle (for example, 5 seconds), a distance traveled after the departure (for example, 100 m), or until the vehicle gets on the guidance route. In this way, by displaying the detailed map when the vehicle departs, it is possible to guide an appropriate travel route that is easy to understand at the time of departure. In particular, it is possible to eliminate the burden of changing the scale in order for the driver to display a detailed map at the start of traveling, thereby contributing to safe traveling.

  Moreover, according to the other form of this invention, the map display method implemented in the vehicle-mounted navigation apparatus which concerns on said form is provided. The map display method according to the embodiment is a map display method implemented in an in-vehicle navigation device having a function of searching for a guidance route to a destination and guiding a vehicle along the guidance route. Detecting the current position of the vehicle; obtaining map data around the current position of the host vehicle; adjusting the map data to detailed map data of a predetermined scale; and When starting and leaving, a step of displaying a detailed map image based on the detailed map data instead of a map image of a scale specified by the user displayed on the screen of the display means; Returning the screen of the display means to the screen on which the map image of the scale specified by the user is displayed after the period of time elapses.

  In the map display method according to this aspect, the predetermined period is a period until a predetermined time elapses until the host vehicle travels a predetermined distance or until the host vehicle travels on the guidance route. It may be either one.

  In the map display method according to this aspect, the step of displaying the detailed map image based on the detailed map data may display the image on one screen of the display means, and the details based on the detailed map data. The step of displaying the map image includes the step of dividing the screen of the display means into two screens, displaying the map image of the scale specified by the user on one screen, and displaying the detailed map image based on the detailed map data on the other screen And displaying the detailed map image based on the detailed map data when the screen of the display means is divided into two screens, the screen is divided into two screens. A detailed map image based on the detailed map data may be a step of displaying a detailed map image based on the detailed map data. Displaying the detailed map image based on the detailed map data on the screen on which the map image with a small scale is displayed when the screen of the display means is divided into two screens. The step of displaying the detailed map image based on the detailed map data may include the step of detecting the scale of the map image displayed on the screen of the display means, and when the scale is a wide area display with a predetermined value or less, And displaying a detailed map image based on the detailed map data on the screen of the display means.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(Configuration of in-vehicle navigation system)
FIG. 1 is a block diagram showing a configuration of an in-vehicle navigation device according to an embodiment of the present invention.

  In the figure, 1 is a DVD-ROM drive, and 1a is a storage medium in which map data and other guidance data are stored. In the present embodiment, the DVD-ROM 1a is used as a storage medium for storing such data, but a hard disk or other storage medium may be used. The map stored here is divided into longitude and latitude widths of appropriate sizes according to each scale level such as 1/1500, 1/25000, 1 / 50,000, 1/10000, etc. Roads, buildings, facilities, and other various properties included in are stored as a coordinate set of points (nodes) expressed in longitude and latitude. Map data includes (1) a road layer composed of a road list, a node table, an intersection configuration node list, etc., (2) a background layer for displaying roads, buildings, parks, rivers, etc. on a map image, (3) It consists of a character / symbol layer or the like for displaying a letter indicating a administrative division name such as a municipality name, a road name, an intersection name, or a map symbol.

  The DVD-ROM 1a stores road data representing the shape of the road used for map matching. This road data is composed of a shape node and a link between shape nodes having different distances between nodes according to the shape of the road.

  An operation unit 2 is provided with operation buttons and the like for operating the navigation apparatus body 10. In this embodiment, the operation unit 2 includes a remote control transmitter, and the user can also operate the navigation apparatus body 10 with the remote control transmitter at hand.

  Also, 3 receives GPS signals sent from a plurality of GPS satellites and generates and outputs GPS data such as longitude, latitude, PDOP (Position DOP) value and HDOP (Horizontal DOP) value of the current position of the vehicle. A GPS receiver is shown. Reference numeral 4 denotes a self-contained navigation sensor. The self-contained navigation sensor 4 is composed of an angle sensor such as a gyro that detects a vehicle rotation angle, and a travel distance sensor that generates a pulse at every constant travel distance.

  Reference numeral 5 denotes a communication device such as an in-vehicle telephone for communicating with various service centers, and 6 denotes a VICS receiver that receives VICS (road traffic information communication system) information transmitted from a radio wave beacon or an optical beacon. These beacons are installed on the roadside and connected to police stations, road managers and integration centers to provide information on traffic jams in the vicinity.

  Reference numeral 7 denotes a display device such as a liquid crystal panel. The navigation device main body 10 displays a map around the current position of the vehicle on the display device 7, guide routes from the departure point to the destination, vehicle marks, Other guidance information is displayed. Reference numeral 8 denotes a speaker for providing guidance information to the user by voice.

  The navigation device body 10 is composed of the following. Reference numeral 11 denotes a buffer memory that temporarily stores map data read from the DVD-ROM 1 a via the DVD-ROM drive 1.

  Reference numeral 12 denotes a control unit constituted by a microcomputer. The control unit 12 has a built-in navigation program, and calculates the current position of the vehicle based on a signal output from the GPS receiver 3 or a signal output from the self-contained navigation sensor 4 according to the program. Or the map data to be displayed is read from the DVD-ROM 1a to the buffer memory 11 via the DVD-ROM drive 1 or from the departure place under the search conditions set using the map data read to the buffer memory 11. Various processes such as searching for a guidance route to the destination are executed. Further, as will be described later, when the vehicle starts and starts (departs) by starting the engine from a parked or stopped state, a process of displaying a detailed map of a predetermined scale on the display device 7 is performed.

  13 is a map drawing unit for generating a map image using the map data read out to the buffer memory 11, and 14 is for generating various menu screens (operation screens) and various marks such as vehicle position marks and cursors according to the operation status. This is the operation screen / mark generator.

  Reference numeral 15 denotes a guide route storage unit that stores the guide route searched by the control unit 12, and 16 denotes a guide route drawing unit that draws the guide route. The guidance route storage unit 15 stores all the nodes of the guidance route searched by the control unit 12 from the departure point to the destination. When displaying the map, the guide route drawing unit 16 reads the guide route information from the guide route storage unit 15 and draws the guide route with a color and line width different from those of other roads.

  Reference numeral 17 denotes a storage unit composed of a hard disk or the like, and display information of the map image displayed on the display device 7 (for example, whether it is a single screen display or a two screen display, or the scale of the displayed map). Value, etc.) are stored. Further, display information saved when the vehicle is parked or stopped is stored.

  An audio output unit 18 supplies an audio signal to the speaker 8 based on a signal from the control unit 12. Reference numeral 19 denotes an image composition unit, which overlays the map image drawn by the map drawing unit 13 with various marks and operation screens generated by the operation screen / mark generation unit 14, the guide route drawn by the guide route drawing unit 22, and the like. Display on the display device 7.

  A process for displaying a detailed map of a predetermined scale when the vehicle departs in the vehicle-mounted navigation device 100 configured as described above will be described with reference to FIGS. 2 and 3 show the screen 20 of the display device 7. FIG. 2 and FIG. 3 show an example in which a guidance route to the destination is searched, the vehicle is driven along the guidance route, and after stopping at a certain point, the vehicle is again departed toward the destination. . In the present embodiment, “at the time of departure” of the vehicle is targeted when the vehicle engine is started from a state where the vehicle engine is turned off and parked or stopped.

  FIG. 2A shows an example in which the screen 20 of the display device 7 is one screen, and the map image 21 is displayed on the screen 20 at a scale (200 m scale) designated by the user. FIG. 2A shows a case in which the vehicle stops at a point A such as a store while traveling according to the guide route 23. The route from the guide route 23 to the point A is searched for and searched by the reroute function. The case where the route 24 (also referred to as the reference route 24) is displayed is shown.

  The control unit 12 of the vehicle-mounted navigation device 100 replaces the map image 21 shown in FIG. 2A displayed on the screen 20 with the map image 21 shown in FIG. As shown in b), a detailed map image 22 (for example, 50 m scale) of a predetermined scale is generated and displayed on the screen 20. In FIG. 2B, since a detailed map around the host vehicle is displayed, a reference route 24 from the host vehicle position CM to the guide route 23 is displayed.

  When leaving the vehicle again, instead of displaying the screen 20 of FIG. 2 (a) with the display of two screens (20a, 20b), a map image 21a with a scale specified by the user as shown in FIG. 2 (c) is displayed. The detailed map image 22a may be displayed on one screen (the left screen 20a in FIG. 2C) and the other map (the right screen 22a in FIG. 2C).

  Note that if the scale of the map shown in FIG. 2A is larger than a predetermined value and is not displayed in a wide area, it is considered that the driver can determine which direction the vehicle should travel from the current position. The detailed map may be displayed only when the wide area map is displayed without displaying the map.

  The detailed map displayed at the time of departure of the vehicle is returned to the original scale map (map screen in FIG. 2A) set by the user after a predetermined period has elapsed. The predetermined period is until a path that is difficult to understand at the time of departure, for example, a predetermined time (for example, 5 seconds), a predetermined travel distance (for example, 100 m), or until the vehicle travels on the guidance path The detailed map is displayed during this period.

  FIG. 3 shows an example in which a map image around the host vehicle is displayed on two screens (20a and 20b) of the display device 7. A map image 21a having a scale of 200 m is displayed on one screen 20a, and a map image 31 having a scale of 150m is displayed on the other screen 20b.

  FIG. 3 (a) shows a case where the vehicle travels along the guide route 23 and stops at a certain point A in the same way as FIG. 2 (a). A case where the route is searched and the searched route (reference route 24) is displayed is shown.

  When the engine of the host vehicle is turned on and the vehicle is started again, the control unit 12 of the in-vehicle navigation device 100 changes the screen of the display unit 7 to one screen 20 and displays the map screen 21a and the screen 20b displayed on the screen 20a. The detailed map image 22 (for example, 50 m scale) is generated and displayed as shown in FIG. In FIG. 3B, since a detailed map around the host vehicle is displayed, a reference route 24 from the host vehicle position CM to the guide route 23 is displayed.

  Further, as shown in FIG. 3C, the setting of the two-screen display is not changed, the detailed map image is displayed on the screen on which the map image with a small scale value is displayed, and the map image with a large scale value is displayed as it is. You may make it do. In FIG. 3A, since the left side of the two screens is 200 m scale and the right side is 150 m scale, the detailed map image 22a is displayed on the left screen 20a.

  After the enlarged map is displayed as shown in FIG. 3B or 3C, the map display screen of FIG. 2B or 2C is returned to the map display screen of FIG. 2A. Similarly to the above, after the lapse of a predetermined period, the original map display screen (FIG. 3A) is restored.

  Also in the case of FIG. 3, as in FIG. 2, when the scale of the map screen displayed on the screen is displaying a wide area map having a predetermined value or less, a detailed map is generated and displayed on the screen. It may be.

  As described above, when the vehicle departs from the guidance route 23 and then departs again, a detailed map around the vehicle is displayed, and not only the guidance route 23 but also the reference route 24 is displayed. The travel route that was unclear on the map becomes clear, and it is possible to prevent the vehicle from traveling in the wrong direction. In addition, it is possible to save the driver from changing to the detailed map at the time of departure, thereby contributing to safe driving.

  In the above description, an example in which two map images with different scale values are displayed on each of the two screens during the two-screen display has been described. However, the present invention is not limited to this, and a map image is displayed on one screen. The other screen may display a video or the like different from the map image. In this case, the detailed map image may be displayed on one screen when the vehicle departs, or the detailed map may be displayed on one of the screens.

  In the detailed map display at the time of vehicle departure described above, the case where the vehicle is driven along the guidance route, the engine of the vehicle is stopped at a facility on the way by a break or the like, and then the vehicle starts again is described.

  The detailed map display operates not only in the case of re-starting as described above, but also when the vehicle departs by searching for a guidance route.

  FIG. 4 shows a case where when a vehicle is parked or stopped at the same point as in FIG. 2, a route search is performed by setting the point as the current position of the vehicle and specifying the point B as a transit point. According to the function for displaying the detailed map at the time of departure of the vehicle described in FIG. 2, the detailed map is displayed when the vehicle engine is started after stopping at the point A. In FIG. It is assumed that a map of a scale specified by the user is displayed and a route search is performed.

  In FIG. 4A, a new guide route 43 is searched, and a reference route 44 from the vehicle position CM to the guide route 43 is searched. When the current position of the vehicle is on a narrow street such as a shopping street, the route to the guidance route is searched as a reference route. Such a route for traveling guidance is displayed, but as shown in FIG. 4A, it is difficult to accurately grasp that the map display is a wide area.

  When leaving the vehicle, the map displayed in FIG. 4A is displayed in place of the detailed map as shown in FIG. 4B. Also, as shown in FIG. 4 (c), a two-screen display is performed, and a map image 41a with a scale set by the user is displayed on one screen (the left screen 20a in FIG. 4 (c)), and the other screen is displayed. The detailed map image 42a is displayed on the screen 20b on the right side in FIG.

  The detailed map image shown in FIG. 4B or 4C may be displayed when a predetermined time has elapsed after the route search.

  The period during which the detailed map in FIG. 4B or 4C is displayed is the same as that in FIG. 2B or FIG. 2C, and the cancellation requirements are also the same. That is, the detailed map is displayed until a predetermined time has elapsed from the departure of the vehicle, until the vehicle travels a predetermined distance, or until the vehicle travels on the guidance route. Thereafter, the map display screen of FIG. 4B or 4C is returned to the map display screen of FIG.

  FIG. 5A shows an example in which a map image around the host vehicle is displayed with two screens (20a and 20b) of the display device 7. A map image 41a having a scale of 200 m is displayed on one screen 20a, and a map image 51 having a scale of 150m is displayed on the other screen 20b.

  FIG. 5B shows an example in which a detailed map is displayed on a single screen when the vehicle departs. FIG. 5C shows an example in which the map image of the wider area is displayed instead of the display of the detailed map image 42a among the two-screen display map images.

  When the detailed map is displayed at the time of departure of the vehicle as shown in FIGS. 5B and 5C, the requirement for canceling the detailed display is set as in the case of FIGS. 4B and 4C. When satisfied, the map display is changed to the original scale display as shown in FIG.

  By displaying the detailed map even when the vehicle is departed by searching for the guidance route in this way, it becomes possible to surely understand the travel route that is difficult to understand with the wide area map, and the vehicle is driven in the wrong direction. Can be prevented. Further, it is not necessary for the driver to adjust the scale of the map screen at the time of departure from the vehicle, and the driver can concentrate on driving, thereby contributing to safe driving.

  As described above, according to the in-vehicle navigation device of the present embodiment, when a vehicle is departed, when a wide-area map in which the map around the own vehicle is larger than a predetermined scale is displayed, A detailed map is displayed only during the period. For example, the wide area map has a scale of 200 m scale or less, and the detailed map displayed at the time of departure has a scale of 50 m scale, for example. Further, the predetermined period is a time after departure of the vehicle (for example, 5 seconds), a distance traveled after the departure (for example, 100 m), or until the vehicle gets on the guidance route. In this way, by displaying the detailed map when the vehicle departs, it is possible to guide an appropriate travel route that is easy to understand at the time of departure. In addition, the burden of changing the scale for the driver to display a detailed map at the time of departure can be eliminated, thereby contributing to safe driving.

  Next, a map display method performed in the in-vehicle navigation device 100 according to the present embodiment will be described. An enlarged guidance process at the time of departure in the map display method will be described in detail with reference to the flowcharts of FIGS.

  FIG. 6 is a flowchart showing an example of processing when the vehicle is departed by searching for a guidance route. FIG. 7 is a processing when the vehicle is stopped along a guidance route and stopped at a certain point and the vehicle is departed again. It is a flowchart which shows an example. FIG. 8 is a flowchart illustrating an example of the enlarged guidance process at departure.

  First, in step S11 of FIG. 6, it is detected that the vehicle engine has been started. In the present embodiment, it is determined that the vehicle is to start when the control unit detects that the vehicle engine is started from a state where the vehicle engine is off.

  In the next step S12, a route search for a guidance route is performed. In the route search, a route search from the current position of the vehicle to the “destination” instructed by the user in setting the route search condition is performed. The controller 12 reads the map data from the DVD-ROM 1a to the buffer memory 11 via the DVD-ROM drive 1 as in the prior art, and automatically uses the search conditions set using the map data read to the buffer memory 11. A guide route from the current position of the car to the destination is searched. The searched route is stored in the route storage unit 15. The “destination” is input by an address, a telephone number, a facility name, or the like. Moreover, you may make it input by touching the destination on the map displayed on the display screen.

  In the next step S13, a “departure expansion guidance process” is performed to display a map around the host vehicle on the screen of the display device 7 at the time of departure, and the process ends.

  FIG. 7 is a flowchart showing an example of processing when the vehicle stops along a guidance route, stops at a certain point in the middle, stops the engine of the vehicle, and starts the vehicle again. Steps S21 and S22 are shown in FIG. This is the same as step S11 and step S12 of FIG.

  In the next step S23, it is detected that the vehicle has stopped or parked halfway, and map image information data such as the travel route until the vehicle stops or parks and the scale of the map displayed on the screen of the display device are stored in the storage unit 17. Saved. It is assumed that the vehicle is parked at a point that is off the guidance route (for example, a facility where meals can be eaten) while traveling along the guidance route searched in step S22. In this case, the reroute function operates to search for a route that leads from the vehicle position to the guidance route and display guidance on the map. In this embodiment, this route is referred to as a reference route, and this reference route is also stored in the route storage unit 15.

  In the next step S24, it is detected that the engine has started. When the engine is started, the control unit 12 acquires the map image information data stored in the storage unit 17 and executes a departure enlarged guidance process in the next step S25 to display an enlarged map and The process ends.

  The “departure expansion guidance process” for displaying a detailed map when the vehicle departs in the flowcharts of FIGS. 6 and 7 will be described with reference to the flowchart of FIG. It is assumed that a map around the vehicle position is displayed on the screen of the display device 7 when this processing is performed.

  First, in step S31, the scale of the map displayed on the screen of the display device 7 is detected. This scale is a scale designated by the user, and is extracted from, for example, the storage unit 17 in which the map image information data is stored.

  When a map is displayed on a one-screen display as shown in FIG. 2A, the scale of the displayed map is extracted. Further, when the map is displayed in the two-screen display as shown in FIG. 3A, the scale of the map displayed on both screens is extracted.

  In the next step S32, it is determined whether or not the map displayed on the screen is in a wide area display. For example, a case where the scale is 200 m or less is defined as wide area display. In the case of one-screen display, it is determined whether or not the displayed map is 200 m scale or less. In the case of two-screen display, it is determined whether or not a map is displayed on any screen at 200 m scale or less. If the map is not displayed in a wide area, it is determined that there is no need to switch from the wide area map to the detailed map, and the departure enlarged guidance process ends. If the map is displayed in a wide area, the process proceeds to step S33.

  In the next step S33, the vehicle position is detected. The vehicle position is detected based on a signal from the GPS receiver 3. In addition, when the vehicle position is detected as the current position when the route search for the guidance route is performed, the information may be used.

  In the next step S34, map data around the vehicle position is acquired. Map data is extracted from map data stored in the DVD-ROM 1a corresponding to the range displayed on the screen at a predetermined scale. The predetermined scale is, for example, a 50 m scale on which a detailed map can be displayed.

  In the next step S35, detailed map data is generated. Based on the map data extracted in step S34, the detailed map data generates image data that displays the vehicle position mark CM and the guidance route in a manner that distinguishes them from other roads. In addition, when displaying on one of the two-screen displays as shown in FIG. 2C, image data is generated by cutting the data on both sides assuming that the generated image data is divided into four in the horizontal direction.

  In the next step S36, the detailed map generated in step S35 is displayed on the screen. In the case of single-screen display, a detailed map (for example, FIG. 2B) is displayed in place of the scale map (for example, FIG. 2A) designated by the user. At this time, the scale value designated by the user is saved in the storage unit 17. Further, a two-screen display is performed, a scale map specified by the user (for example, the map screen 21a in FIG. 2C) is displayed on one screen, and a detailed map (for example, FIG. 2C) is displayed on the other screen. The map screen 22a) may be displayed.

  In the case of two-screen display, the screen is switched to single-screen display, and a detailed map image (for example, FIG. 3B) is displayed. Further, a detailed map may be displayed on the screen on which the wide area map is displayed instead of the wide area map. Also in this case, the scale value of the wide area map is saved in the storage unit 17.

  In the next step S37, it is determined whether or not the detailed map display release requirement is satisfied. The process waits until the release requirement is satisfied. When the release requirement is satisfied, the process proceeds to step S38. The release requirement is when a predetermined time has elapsed since the vehicle started to travel. The predetermined time may be a time until the section of the route that is difficult to understand on the wide-area map at the time of departure is taken, for example, 10 seconds. The predetermined time may be set as the time required for the guidance route, and the time may be set as the predetermined time. If the vehicle is stopped at a midpoint while traveling along the guide route, measure the time from the guide route until the vehicle stops halfway, and set the time as a predetermined time. Also good.

  Another cancellation requirement may be a case where the vehicle has traveled a predetermined distance after the start of travel. The predetermined distance may be a distance until the section of the route that is difficult to understand on the wide area map at the time of departure, for example, 100 m. The predetermined distance may be a distance to the guide route. When driving along a guide route, if the vehicle is stopped at an intermediate point, measure the distance from the guide route to the place where the vehicle stopped halfway, and set the distance as a predetermined distance. Also good.

  Furthermore, as another release requirement, the vehicle may start traveling on the guidance route. In this case, it is not necessary to display the detailed map any more because the route which has been difficult to understand such as a narrow street has already been taken out. The position of the host vehicle is detected based on a signal input from the GPS receiver, and it is determined whether or not the host vehicle is traveling on the guide route from the guide route information and map data stored in the guide route storage unit. .

  In the next step S38, processing for returning the map display screen to the original map of the scale set by the user is performed. In this case, the map is displayed again at the scale designated by the user based on the scale value saved in the storage unit 17 in step S36, and the detailed map display process at the start of vehicle travel is completed.

  In the above process, the detailed map is displayed when the map displayed on the screen in step S32 is a wide area map. However, the detailed map of a predetermined scale may be displayed uniformly when the vehicle departs. Good.

  As described above, according to the map display method of the present embodiment, when a vehicle is departed, when a wide-area map in which the map around the host vehicle is larger than a predetermined scale is displayed, the predetermined map is displayed after the departure. A detailed map is displayed only for the period. For example, the wide area map has a scale of 200 m scale or less, and the detailed map displayed at the time of departure has a scale of 50 m scale, for example. Further, the predetermined period is a time after departure of the vehicle (for example, 5 seconds), a distance traveled after the departure (for example, 100 m), or until the vehicle gets on the guidance route. In this way, by displaying the detailed map when the vehicle departs, it is possible to guide an appropriate travel route that is easy to understand at the time of departure. In addition, the burden of changing the scale for the driver to display a detailed map at the time of departure can be eliminated, thereby contributing to safe driving.

It is a block diagram which shows the structure of the vehicle-mounted navigation apparatus which concerns on one Embodiment of this invention. FIG. 6 is a diagram (part 1) for explaining an enlarged guidance display at the time of restart after a halfway stop in the in-vehicle navigation device according to FIG. 1; FIG. 6 is a diagram (No. 2) for explaining an enlarged guidance display at the time of re-starting after an intermediate stop in the in-vehicle navigation device according to FIG. 1. FIG. 6 is a diagram (part 1) for explaining an enlarged guidance display at the time of departure in the vehicle-mounted navigation device according to FIG. 1; FIG. 8 is a diagram (part 2) for explaining an enlarged guidance display at the time of departure in the vehicle-mounted navigation device according to FIG. 1. It is a flowchart which shows an example of the guidance display process at the time of the departure in the vehicle-mounted navigation apparatus which concerns on FIG. It is a flowchart which shows an example of the guidance display process at the time of the restart after the middle stop in the vehicle-mounted navigation apparatus which concerns on FIG. It is a flowchart which shows an example of the expansion guidance display process at the time of departure in the flowchart of FIG.6 and FIG.7.

Explanation of symbols

100: In-vehicle navigation device,
1a ... DVD-ROM (storage means),
2 ... operation part (information input means),
3 GPS receiver (own vehicle position detection means),
4. Self-contained navigation sensor (own vehicle position detection means),
7: Display section (display means),
10 ... navigation device body,
11: Buffer memory (storage means),
12 ... Control part (control means),
15 ... Guidance route storage unit (storage means),
17 ... Storage part (storage means),
20, 20a, 20b ... screen,
21, 21a, 22, 22a, 41, 41a, 42, 42a, 31, 51 ... map image,
23, 43 ... guidance route,
24, 44 ... Reference route.

Claims (15)

A vehicle-mounted navigation device having a function of searching for a guidance route to a destination and guiding a vehicle along the guidance route,
Display means;
Storage means for storing map data;
Own vehicle position detecting means for detecting the current position of the own vehicle;
Control means for displaying on the screen of the display means a detailed map image in which the scale of the map around the current position of the host vehicle on which the guidance route is displayed is adjusted for a predetermined period from when the host vehicle departs;
A vehicle-mounted navigation device comprising:   The predetermined period is either until a predetermined time elapses, until the own vehicle travels a predetermined distance, or until the own vehicle travels on the guidance route. The in-vehicle navigation device according to claim 1.   The said control means displays the said detailed map image on the screen of the said display means when the map image of the scale by a user's instruction | indication is displayed on the screen of the said display means. Car navigation system.   The control means divides the screen of the display means into two screens and displays the map image of the scale on one screen when a scale map image according to a user instruction is displayed on the screen of the display means. The vehicle-mounted navigation device according to claim 2, wherein the detailed map image is displayed on the other screen.   3. The control unit according to claim 2, wherein when the screen of the display unit is divided into two screens, the control unit displays the detailed map image on the one screen with the two screens as one screen. 4. Car navigation system.   The in-vehicle navigation device according to claim 2, wherein when the screen of the display means is divided into two screens, the control means displays the detailed map image on one screen.   7. The control unit according to claim 3, wherein when the predetermined period has elapsed, the screen of the display unit is returned to the pre-departure screen on which a scaled map image is displayed according to an instruction from the user. The in-vehicle navigation device according to any one of the above.   The control means causes the detailed map image adjusted in scale to be displayed on the screen of the display means when the scale of the map image displayed on the screen of the display means is a wide area display with a predetermined value or less. The in-vehicle navigation device according to claim 2, wherein A map display method implemented in an in-vehicle navigation device having a function of searching a guidance route to a destination and guiding a vehicle along the guidance route,
Detecting the current position of the host vehicle;
Obtaining map data around the current position of the host vehicle;
Adjusting the map data to detailed map data of a predetermined scale;
A step of displaying a detailed map image based on the detailed map data instead of a map image of a scale specified by the user displayed on the screen of the display means when the vehicle starts by starting an engine;
Returning the screen of the display means to a screen on which a map image of a scale specified by the user is displayed after a predetermined period of time has passed since the host vehicle departed;
A map display method characterized by comprising:   The predetermined period is either until a predetermined time elapses, until the own vehicle travels a predetermined distance, or until the own vehicle travels on the guidance route. The map display method according to claim 9.   The map display method according to claim 10, wherein the step of displaying a detailed map image based on the detailed map data displays the image on one screen of the display means. Displaying the detailed map image based on the detailed map data, dividing the screen of the display means into two screens;
Displaying a map image of a scale specified by the user on one screen, and displaying a detailed map image based on the detailed map data on the other screen;
The map display method according to claim 10, further comprising:   The step of displaying the detailed map image based on the detailed map data is a step of displaying the detailed map image based on the detailed map data on the screen when the screen of the display means is divided into two screens. The map display method according to claim 10.   In the step of displaying the detailed map image based on the detailed map data, when the screen of the display means is divided into two screens, the detailed map image based on the detailed map data is displayed on the screen on which a small scale map image is displayed. The map display method according to claim 10, wherein the map display method is a step of displaying. The step of displaying a detailed map image based on the detailed map data includes:
Detecting the scale of the map image displayed on the screen of the display means;
A step of displaying a detailed map image by the detailed map data on the screen of the display means when the scale is a wide area display of a predetermined value or less;
The map display method according to claim 10, further comprising:

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