JP4345255B2 - Navigation center apparatus and navigation apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention provides a navigation center device suitable for providing data necessary for route guidance from the center side to the moving side.And navigation deviceIt is about.
[0002]
[Background]
In a navigation system that is generally widespread, a navigation device is mounted for each moving body, for example, a vehicle, and route guidance is performed using map data stored in a CD-ROM or the like for each vehicle. ing. However, in such a system, it is necessary to constantly purchase new CD-ROMs corresponding to new construction or abolition of roads. Further, if the type of media is different as in a DVD-ROM or the format is different even if the type is the same, the navigation device itself must be replaced.
[0003]
On the other hand, Japanese Patent Laid-Open No. 10-19588 discloses a navigation system that transmits map images and optimum route data necessary for guiding a vehicle to a destination from the center (base) side to the vehicle side. It is disclosed. According to this system, communication is performed between the data transmission system on the center side and the vehicle navigation apparatus on the moving side. The data transmission system has a database that stores data necessary for guiding a vehicle to a destination. The data transmission system reads out necessary data from a database based on a request from a vehicle navigation device and creates a map image. In addition, route search is performed to create optimum route data. The created map image and data indicating the optimum route are transmitted to the vehicle side. In the vehicle navigation apparatus, corresponding display is performed based on the map image and the optimum route data transmitted from the system side.
[0004]
[Problems to be solved by the invention]
By the way, in the background art described above, route data and a map image from the departure point to the destination obtained on the center side are transmitted to the moving side as they are. For this reason, on the moving side, from departure to arrival at the destination, map images corresponding to the travel position are sequentially displayed on the display of the navigation device.
[0005]
However, a driver who is driving a car does not always look at the display of the navigation device while driving, but often refers to a point on a route such as an intersection that turns right or left. If the vehicle goes straight even at an intersection, it is not necessary to refer to the navigation device. From this point of view, if there is only data of important points that require guidance, such as intersections and turning points that turn right and left in the route data and map data, the function as navigation can be achieved. Further, if only necessary data is sent from the center side to the moving side in this way, the amount of data to be accumulated on the moving side is considerably reduced, and the moving side device can be simplified.
[0006]
The present invention pays attention to the above points, and its object is to reduce the amount of data transmitted from the center side to the moving side. Another object is to provide good route guidance even if the amount of data transmitted to the mobile side is reduced. Yet another object is to simplify the mobile device.
[0007]
[Means for Solving the Problems]
  The navigation center apparatus of the present inventionA navigation center device for providing road data and guidance data necessary for route guidance from a departure place to a destination for a navigation device having no means and data for performing a route search, the road data and route guidance. Data storage means for storing data, reception means for receiving data relating to a departure place and a destination from the navigation device, and route search based on data received by the reception means by using data of the data storage means A route search unit, a route change point extraction unit that extracts a route change point on the route searched by the route search unit, and a peripheral region around the route change point extracted by the route change point extraction unit Peripheral area setting means and route guidance data in the peripheral area set by the peripheral area setting means are stored in the data A transmission for transmitting the guidance data acquisition means obtained from the steps, the road data of the route searched by the route search means, and the route guidance data in the peripheral area obtained by the guidance data acquisition means to the navigation device, respectively. Means,It is provided with.
  The navigation device of the present invention includes a data storage means for receiving and storing data transmitted from the navigation center device, a position measurement means for measuring a current position, and data of a peripheral region corresponding to a measurement result thereby. It comprises a route guidance unit that reads out from the data storage unit and performs route guidance based on the data.The above and other objects, features and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail. In the following embodiments, a case where a vehicle is assumed as the moving side and the present invention is applied to an in-vehicle navigation device will be described as an example. The operation of route guidance for guiding the vehicle to the destination will be mainly described.
[0009]
First, the outline of the following form will be described. On the center side, a route search is performed with reference to a database, and further a route change point such as a right or left turn existing in this route is extracted. Detailed guidance data is transmitted to the moving side around the route change point. On the moving side, map display and voice guidance are performed based on the route / guidance data transmitted from the center side. These route guidances are performed in detail at the route change point and the vicinity thereof, and are simplified in the middle of other routes. Since the route search is performed on the center side and not on the moving side, it is not necessary to have map data or the like on the moving side, and the apparatus configuration is simplified. Further, since only the main data necessary for route guidance is transmitted, the amount of data transmitted from the center side to the moving side is reduced. However, detailed guidance data is transmitted for the route change point and its surroundings, so that route guidance is performed well.
[0010]
Embodiment 1
(1) Overall Configuration First, the overall configuration of this embodiment will be described with reference to FIG. FIG. 1 shows a configuration of a navigation system according to the present embodiment. The navigation system of this embodiment is configured by a center device 150 on the center side and an in-vehicle navigation device 100 on the moving side.
[0011]
First, from the center device 150, the communication control unit 151 is a communication device including a modem, a terminal adapter, etc.In-vehicleThis is for transmitting / receiving data to / from the navigation device 100. A communication system such as a car phone, a mobile phone, or a PHS may be used. The system control unit 152 includes an arithmetic processing unit that includes a CPU and a memory. The memory stores various programs executed by the center device 150, such as a route search program for searching for a route from the designated departure point to the destination, and a program for extracting route / guide data to be transmitted to the vehicle. Has been. The memory also has a working area used for executing these programs.
[0012]
The database 153 is a large-capacity storage medium such as a hard disk and stores data necessary for route search and route guidance, such as route data representing routes, search data for searching routes, and guidance data for guiding routes. Yes. Specific examples are as follows.
(1) Map data: Data for displaying a map on the display of the navigation device.
(2) Road data: As shown in FIG. 2 (A), road number string, node point number and position (longitude / latitude) set on each road, road name, road type, road length, drawing data Etc. The road drawing data may be vector data composed of a plurality of drawing coordinates, or may be bitmap image data.
(3) Intersection data: As shown in FIG. 2 (B), intersection number string, intersection name, position (longitude / latitude), guidance voice for instructing the course change direction of the intersection, so-called land that serves as a guide mark Data such as marks and landscapes of major buildings. The intersection includes a branch point.
▲ 4 ▼Search data: Data for specifying the location (longitude and latitude) of the destination from the telephone number, address, name, etc.
[0013]
Further, the position correction unit 154 is for correcting position data by GPS (or hybrid navigation in consideration of autonomous navigation) transmitted from the vehicle side using so-called D-GPS. Although such a function can be provided on the vehicle side, the facility burden on the vehicle side is reduced by providing the function on the center side.
[0014]
Next, the in-vehicle navigation device 100 will be described. The arithmetic processing unit 101 is configured mainly with a CPU. The program storage unit 102 is a center device150A memory for storing a program executed by the arithmetic processing unit 101 such as a program for displaying a route on the display unit 106 based on route / guidance data transmitted from the voice, a program for outputting voice of route guidance from the voice output unit 107 It is.
[0015]
The data storage unit 103 functions as a working area that is appropriately used when executing the program, and stores, for example, the following data.
(1) Center device150Route / guide data (route data and guide data) sent from
(2) ID data unique to the vehicle,
(3) Vehicle position data (longitude / latitude) measured by the position measurement unit 104)
[0016]
Among these, the vehicle position data includes a plurality of past position data in addition to the current position data measured at predetermined time intervals by the position measurement unit 104. For example, position data of measurement points included in a certain distance or position data of a certain number of measurement points is stored. When the position measurement unit 104 newly performs measurement, the latest position data is stored, and the oldest stored position data is deleted. By connecting the plurality of position data, a travel locus of the vehicle can be obtained. As will be described later, this travel locus is used for so-called map matching for specifying the road on which the vehicle is traveling.
[0017]
Next, the position measuring unit 104 is for measuring the position of the vehicle using so-called GPS, and receives a signal from a plurality of GPS satellites to measure the absolute position of the vehicle. Are provided with a speed sensor, an orientation sensor, and the like. Speed sensors and azimuth sensors are used for autonomous navigation. The relative position measured by these sensors is used to obtain the position in a tunnel where the GPS receiver cannot receive radio waves from the satellite, or to correct the positioning error of the absolute position measured by the GPS receiver. .
[0018]
The input unit 105 includes various switches, a touch panel attached to the display surface of the display unit 106, a remote controller, a data input device using voice recognition, and the like. On the touch panel, when a user touches an icon or the like displayed on the display unit 106 with a finger, corresponding data and commands are input. In a data input device using voice recognition, corresponding data and commands are input when a user utters a voice.
[0019]
The display unit 106 is a display using liquid crystal, CRT, or the like, and includes a touch panel as described above. The transmission / reception unit 108 is a communication device for transmitting / receiving data to / from the center device 150 side, and includes a modem. A system such as a car phone, a mobile phone, or a PHS may be used.
[0020]
(2) Operation on the center device side ... Next, a schematic operation of the center device 150 will be described. FIG. 3 is a flowchart showing route / guidance data extraction and transmission processing by the center device 150.
[0021]
(2-1) Determining destination and starting point: First, the starting point and destination determining operation necessary for route search will be described. In this case, along with the route search request from the in-vehicle navigation device 100, the vehicle ID, the current location of the vehicle (longitude / latitude, east longitude / north latitude in Japan), destination data (phone number corresponding to the facility at the destination, Address etc.) is transmitted to the center apparatus 150. These data are received by the communication control unit 151 of the center apparatus 150 and sent to the system control unit 152. Then, the system control unit 152 determines that there is a route search request (Yes in step S1).
[0022]
The system control unit 152 determines a departure place and a destination (step S2). First, as the starting point of the route search, the current position data of the vehicle transmitted from the in-vehicle navigation device 100 is corrected by the position correction unit 154 if necessary. Based on the corrected current position data, the current position of the vehicle or an intersection near itPoint of departureSet as On the other hand, for the destination, the database 153 is referred to, and the location of the facility corresponding to the telephone number or address transmitted from the in-vehicle navigation device 100 is read from the database 153. Next, the read facility location or an intersection near the facility location is set as a destination for route search. When a plurality of destinations are applicable, the vehicle side is notified as described later and either one is selected.
[0023]
(2-2) Route Search ... Next, the system control unit 152 executes a route search program based on the position data of the departure point and the destination, and recommends from the set departure point to the destination. A route is searched (step S3). As a route search method, for example, the distance from the departure point to the destination is the shortest, the travel time is the shortest, the transit point is taken into account, the traffic congestion data obtained from VICS, etc. and the road construction data are taken into account. Various methods are known, such as.
[0024]
The searched route is represented by an intersection number or a road number included from the departure point to the destination. FIG. 4 shows an example of a route searched for by the system control unit 152. In FIG. 4, the part indicated by the solid line is the searched route. R1 to R9 represent road numbers, and C1 to C8 represent intersection numbers. For example, the road number R2 represents a road between the intersections C1 and C2. The same applies to other roads. As shown in FIG. 2, the road data of each road number includes data such as node point data for road drawing and road length. Further, the intersection data of each intersection number includes position data, name, and the like. These data are stored in the database 153 together with the numbers. The road number of the route searched in this way is as shown in FIG. 5 (A), and the intersection number is as shown in FIG. 5 (B). Further, the relationship between the approach path and the exit path at each intersection is as shown in FIG. These search results are temporarily held in the system control unit 152.
[0025]
(2-3) Identification of route change point ...... Next, in the system control unit 152, an intersection on the route searched as described above is an intersection (or branch) where the route should be changed such as a right or left turn. Point), that is, an intersection determination process for identifying whether or not it is a course change point, and a process for counting the total number of course change points is performed (step S4). The determination of the course change point is made based on whether or not the intersection existing on the searched route enters or exits along the road in a straight line or a gentle curve. That is, when the angle between the approach path and the exit path is equal to or less than a predetermined value, the intersection is determined to be a course change point.
[0026]
As an example, FIG. 6 shows a processing method for determining whether or not the intersection C3 in FIG. 4 is a course change point. In the example of FIG. 4, the approach path to the intersection C3 is R3, and the exit path is R4. In the system control unit 152, the data of these approach paths and exit paths are obtained from the search results shown in FIG.
[0027]
On the other hand, the data shown in FIG. 2 is stored in the database 153 as described above. The system control unit 152 refers to the database 153 and reads out the longitude and latitude data of the node points DT3 and DT4 adjacent to the intersection C3 and the longitude and latitude data of the intersection C3 among the node points of the approach route R3 and the exit route R4. It is. Then, using these longitude and latitude data, the angle θh between the approach path R3 and the exit path R4 is obtained. When this angle θh is smaller than a preset reference angle θT, that is, if θh <θT, it is determined that the vehicle changes the course at the intersection C3, and the intersection is determined to be a course change point. To do. The determination as to whether or not the route is changed is made for all intersections on the searched route.
[0028]
(2-4) Setting of peripheral area and extraction of area guidance data ...... Next, the system control unit 152 sets a counter i for the total number n of route change points obtained as described above (step S5). . For each course change point, a certain range including it is obtained as the peripheral area. For example, in the example of FIG. 4, the peripheral area A1 centering on the intersection C3 which is a course change point is obtained. Then, map data, road data, and intersection data corresponding to the peripheral area A1 are read from the database 153 (step S6). The same applies to the intersection C6. If the vehicle goes straight on the road, there will be no inconvenience even if there is no map. However, at the course change point, the course must be changed, such as turning left or right, so it is necessary to display a map or a landscape or to provide guidance by voice. Therefore, detailed route guidance data is extracted from the database 153 for a certain range including the route change point. Data corresponding to these peripheral areas is set as area guide data. This process is performed for all the course change points (steps S7 and S8), and the area guidance data corresponding to the peripheral area is stored in the working area together with the data representing the peripheral area.
[0029]
Next, a method for setting a peripheral area centered on a course change point will be described. The peripheral area is set so as to develop into an appropriate shape such as a circle or a rectangle in front of the approach path, for example, with the course changing point as the center. Even if it is not centered on the course change point, it is sufficient to include it. When the peripheral area is set in a circular shape, the diameter d [Km] of the circle centering on the course change point may be set most simply. However, in-vehicle navigation device100Display part106Is normally rectangular, it is convenient if the surrounding area is also rectangular.
[0030]
When the peripheral area is set in this rectangular shape, it is necessary to set the size n [km] × m [km] of each side of the rectangle and also set the direction thereof. For example, the peripheral area A1 with respect to the course change point C3 indicated by the alternate long and short dash line in FIG. 4 is a square of n [km] × n [km] square. The value of n that determines the size of the peripheral area A1 may be set in advance in the program of the system control unit 152, or an arbitrary value is set on the in-vehicle navigation device 100 side and the center device 150 side You may make it transmit to. In any case, the value of n is set in consideration of the map matching viewpoint as will be described later. In the case of n × m, it is necessary to determine the value of m, but for example, it is set by multiplying n by a predetermined coefficient.
[0031]
Next, an n × n rectangular range centering on the intersection C3 which is a course change point is set from the value of n. Then, the rectangular area is rotated around the intersection C3, and a peripheral area is set at an appropriate position. This setting is performed so that, for example, a straight line connecting the intersection position M between the approach path to the intersection C3 and one side of the rectangular range and the intersection C3 is orthogonal to one side of the rectangular range. In other words, the approach path with respect to the intersection C3 and one side of the rectangular range are orthogonalized. Such a range setting takes into account that a map on the side of the in-vehicle navigation device to be described later is displayed in a heading-up manner on a rectangular screen.
[0032]
In the system control unit 152, n × n diagonal positions (Xca3, YCa3), (Xcb3, Ycb3) of the rectangular range are determined by any method and set as the peripheral area A1. The specific values of the diagonal positions (Xca3, YCa3), (Xcb3, Ycb3) are represented by longitude and latitude. In the system control unit 152, area guide data such as map data and road data corresponding to the peripheral area A1 is extracted from the database 153, and the process of the diagonal positions (Xca3, YCa3) and (Xcb3, Ycb3) of the peripheral area A1. It is stored in the working area together with the degree data. The same applies to the peripheral area A4 of the intersection C6.
[0033]
In addition, a peripheral area is set in advance for each combination of an approach path and an exit path at each intersection, and corresponding area guide data is prepared in the database 153 in the form of a table, and the corresponding area is determined from the peripheral area table. You may make it read guidance data. In this way, there is an advantage that it is not necessary to perform arithmetic processing for setting the peripheral area.
[0034]
In the present embodiment, as shown in FIG. 4, the area guidance data is similarly extracted for the peripheral area A2 centered on the departure point PD and the peripheral area A3 centered on the destination PA. The guidance data for each of these areas is not always necessary. For example, when both the starting point and the destination are well known, the area guidance data only near the route change point on the route on the way is sufficient. However, for the departure point PD, it is convenient to have area guidance data when it is unclear which direction it will travel, and for the destination PA, area guidance such as the presence or absence of parking lots and various facilities in the vicinity. It is convenient to have data. These guidance data may be any of vector data, bitmap data, a combination thereof, and the like.
[0035]
Further, the system control unit 152 generates a route schematic diagram along with the creation of the guidance data. This route schematic displays the entire searched route, and displays the route searched using a marker or the like on a reduced scale map including all the routes. This route schematic diagram is used to determine whether or not the user on the vehicle side is appropriate for the searched route.
[0036]
(2-5) Route map and transmission of route / guide data: Route / guide data including the route map, road data, intersection data, and area guide data obtained as described above is controlled by the in-vehicle navigation device 100. Transmitted by the unit 151 (step S9). At this time, with reference to the vehicle ID received at the time of the route search request in step S1, data is transmitted to the corresponding vehicle. First, a route map is transmitted.
[0037]
FIG. 7 shows the main contents of the route / guide data transmitted to the in-vehicle navigation device 100. First, FIG. 7A shows the position data of the departure place and the destination, and is expressed by longitude and latitude. FIG. 7B shows road data included in the searched route, and includes a road number and various data corresponding thereto (see FIG. 2A). FIG. 7 (C) is the intersection data included in the searched route. The intersection number and various data corresponding thereto (see FIG. 2 (B)) and the approach route and the exit route shown in FIG. 5 (C) are shown. Contains data.
[0038]
FIG. 7D shows area guidance data regarding a course change point in the search route and its surrounding area. The intersection number corresponding to the route change point, the diagonal position data of the surrounding area corresponding thereto, the corresponding guidance data, the road number of the approach route and the exit route are included. The guidance data includes map data, voice guidance data, landmark data as landmarks for guidance, landscape image data, and the like corresponding to intersections of course changes and surrounding areas. In addition, data indicating the travel direction or travel route to the first course change point as viewed from the guidance start position is also added as necessary. These are in-vehicle navigation devices100If displayed on the map on the side, more accurate guidance is possible. Each of these data is transmitted to the in-vehicle navigation device 100 alone or in combination as appropriate.
[0039]
As described above, according to the flowchart of FIG. 2, data necessary for route search and guidance of the searched route is obtained and transmitted to the vehicle side using a mobile phone or the like. The transmitted route map and guidance data are received by the transmission / reception unit 108 of the in-vehicle navigation device 100 and further stored in the working area of the data storage unit 103.
[0040]
(3) Operation of In-vehicle Navigation Device Next, the operation in the in-vehicle navigation device 100 will be described. 8 and 9 are flowcharts showing the operation of the in-vehicle navigation device 100. In FIG. 8, steps S130 and S131 will be described in a later embodiment.
[0041]
(3-1) Determination of Departure Point and Destination ... The in-vehicle navigation device 100 first acquires GPS data by the position measurement unit 104 and measures the current position (longitude / latitude) of the vehicle (step S101). On the other hand, the user of the in-vehicle navigation device 100 uses the input unit 105 to input a destination facility name, a telephone number, an address, or the like, and requests a route search (step S132). Then, the vehicle current position is transmitted to the center apparatus 150 together with the vehicle ID as the departure point data and the destination telephone number and address as the destination data.
[0042]
In the center device 150, first, a correction process by D-GPS is performed on the current position by the position correction unit 154, and a departure position or an intersection in the vicinity thereof is determined as a departure point based on the corrected current position data. On the other hand, the destination is determined for the destination facility or an intersection in the vicinity thereof from the transmitted telephone number, address or facility name. The determined destination and departure point data are transmitted from the center device 150 to the in-vehicle navigation device 100 and displayed on the display unit 106 (step S133).
[0043]
In this case, for example, when the input telephone number is only the first few digits and there are a plurality of corresponding facilities, a plurality of destinations corresponding to them are transmitted and displayed. The user looks at this display and determines whether the starting point and the destination are appropriate, or selects a corresponding one from a plurality of destinations (No in step S134, S138). The result is sent from the transmission / reception unit 108 to the center device.150Will be notified. In this way, the starting point and destination for route search are determined.
[0044]
(3-2) Route Search: The center device 150 performs a route search based on the starting point and destination determined as described above, and further creates a route schematic. On the display unit 106, the searched route is displayed as a route schematic diagram (step S135). An example of this display is shown in FIG. 10A, for example. The illustrated example corresponds to the searched route of FIG. 4, and intersections C3 and C6 exist in the route as route change points. The distance from the departure point PD to the intersection C3 is LA [km], the distance from the intersection C3 to the intersection C6 is LB [km], and the distance from the intersection C6 to the destination PA is LC [km]. The user determines whether the route is a desired route by referring to such a route schematic diagram, and if there is any inconvenience, requests the search again (No in step S136, S137). For example, conditions such as time priority, distance priority, and waypoint designation are added. If the search result is good (Yes in step S136), the center device 150 is notified of this. Then, the corresponding route / guide data (see FIG. 7) is transmitted to the in-vehicle navigation device 100 and stored in the data storage unit 103.
[0045]
(3-3) Around the destination: As the vehicle departs and moves, the position measurement unit 104 measures the vehicle position at every elapse of a predetermined time or every movement of a predetermined distance, and the measurement result is stored as data. Stored in the unit 103 (step S106). The arithmetic processing unit 101 refers to the route / guidance data in the data storage unit 103, and outputs the route / guidance data corresponding to the current position, if any. That is, the map data is displayed on the display unit 106, and the audio data is output to the audio output unit 107 (step S107). Referring to the example of FIG. 4, immediately after departure, the route / guidance data of the peripheral area A <b> 2 of the departure point PD is stored in the data storage unit 103, and is read from the data storage unit 103. Then, a map around the departure point PD is displayed on the display unit 106, and route guidance voice is reproduced by the voice output unit 107. The arithmetic processing unit 101 performs so-called map matching on the route / guide data, and also displays the current vehicle position on the display unit 106.
[0046]
FIG. 10B shows an example of a map display. As shown in the figure, a map around the departure point PD is displayed. On this map, the road R1 is emphasized by the mark MA, indicating that this is the searched route. An arrow mark MB indicating the traveling direction is also displayed. A vehicle position mark MC by map matching is also displayed. Such a display is performed until the vehicle deviates from the departure position peripheral region (No in step S108).
[0047]
(3-4) On-the-route route: When the vehicle travels the search route and the arithmetic processing unit 101 determines that the vehicle has escaped from the departure point peripheral area A2 (Yes in step S108), map matching is also interrupted. . Then, a simple guidance screen as shown in FIG. 11A is displayed on the display unit 106 (step S109). In FIG. 11A, the contents of the display “Lv [km] to XX intersection” and “Lw [km] to destination” are the data of each road transmitted as route / guide data from the center device 150. The calculation processing unit 101 calculates the distance traveled since the departure.
[0048]
As described above, the road and intersection data in the route searched for on the center device 150 side includes the numbers arranged in the order of the route and the data corresponding to each number as shown in FIG. . The road data includes the road length, and the intersection data includes the position. On the other hand, the current position is measured, and the travel distance from the departure place can also be calculated. By using these data, the distance from the current position to the next course change point or destination can be calculated.
[0049]
The display of FIG. 11A is a simple one including an arrow mark MD indicating the traveling direction, a vehicle position mark ME, a background image MF, and a distance display MG. The arrow mark MD indicates the course change direction at the next course change point as seen from the vehicle position. In the example of FIG. 4, since the right turn is made at the course change point C3, the arrow mark MD is directed to the right. The image data necessary for display may be included in the route / guidance data and transmitted from the center device 150 to the in-vehicle navigation device 100, or may be stored in the data storage unit 103 in advance by the in-vehicle navigation device 100. May be.
[0050]
In this way, a simple display only displays a guidance screen on a midway route where no detailed guidance data exists. However, there is no particular inconvenience because the vehicle only needs to travel along the road. Such simple display is performed until it enters the peripheral area A1 of the course change point C3 (No in step S110).
[0051]
(3-5) Around route change point: When the vehicle travels the search route and enters the peripheral area A1 of the route change point C3 (Yes in step S110), map matching is started (step S111). The map of the peripheral area A1 is the dataStorage unit 103Is displayed on the display unit 106. Corresponding audio data is output from the audio output unit 107. Then, when approaching the course change point C3 (Yes in Step S112), an enlarged view of the intersection C3 is displayed on the display unit 106 (Step S113). Alternatively, a simplified display as shown in FIG. The user can turn right at the intersection C3 according to the map display and the voice guidance, and can proceed on the searched route. The display around the intersection C3 is performed until the surrounding area A1 is escaped (No in step S114). After exiting the peripheral area A1 of the route change point C3, the route on the way shown in FIG. 11A is displayed again (No in step S115). The same applies to the peripheral area A4 around the course change point C6.
[0052]
(3-6) Around Destination: When the arithmetic processing unit 101 determines that the vehicle has traveled the search route and entered the surrounding area A3 of the destination PA (Yes in step S115), map matching is resumed. And the map of the surrounding area A3 is dataStorage unit 103Are displayed on the display unit 106 (step S116). Corresponding audio data is output from the audio output unit 107. The user can travel on the searched route according to the map display and the voice guidance, and can arrive at the destination PA. In this case, an enlarged view of the vicinity of the destination PA may be displayed on the display unit 106 at a point in time before reaching a predetermined distance before the destination PA. Then, when the vehicle arrives at the destination PA, the route guidance operation ends (step S117).
[0053]
As described above, according to this embodiment,
(1) A route search is performed on the center side, and a route change point and its surrounding area are extracted. And about guidance data, such as a map and an audio | voice, only the surrounding area containing a course change point and the surrounding area of a departure place and a destination are sent to the vehicle side.
(2) On the vehicle side, the route / guidance data sent from the center side is used, and a detailed map is displayed and guidance is provided for the departure point, route change point, and destination in detail. .
[0054]
For this reason, the amount of data transmitted from the center side to the vehicle side is reduced, and the navigation device on the vehicle side is simplified such as a reduction in memory capacity. Even if the amount of data is reduced, route guidance is performed well.
[0055]
Embodiment 2
Next, Embodiment 2 of the present invention will be described. This form 2 provides the technique for obtaining the guidance data for the peripheral area centered around the route change point, that is, the operation of step S6 in FIG. The peripheral region is an n × n rectangular range in the example of FIG. 4, but in this embodiment, this range is set in consideration of the map matching viewpoint.
[0056]
(1) Map matching: As described above, at the departure point, the route change point, and the destination, a map of the surrounding area is displayed, and map matching is performed by the in-vehicle navigation device 100 so that the vehicle is displayed on the map. The position is displayed. First, a simple example of map matching will be described with reference to FIG. Map matching is a process for applying and displaying the current vehicle position on a route (road) in a displayed map, as already known. The vehicle position obtained by the position measurement unit 104 of the in-vehicle navigation device 100 generally includes a certain amount of measurement error. Therefore, if the position is displayed as it is based on the measured data, the vehicle position may not be displayed on the route, for example, the corresponding part is off the road. For this reason, such an error is corrected by performing map matching in the in-vehicle navigation device 100 so that the current vehicle position can be displayed on the map.
[0057]
FIG. 12 shows a simple example of map matching. As described above, the road data on the searched route is transmitted from the center device 150 to the vehicle-mounted navigation device 100 together with the number and corresponding data, and stored in the data storage unit 103. Since the road data includes the longitude and latitude values of each node point, the road can be drawn by plotting this value. FIG. 12A shows a road plotted by plotting the node point data DT. On the other hand, in the in-vehicle navigation device 100, the vehicle position is measured by the position measurement unit 104 and stored in the data storage unit 103. When this measurement point DS is plotted, the traveling locus of the vehicle can be drawn as shown in FIG.
[0058]
Comparing these two patterns, the road pattern in the section ΔK from the node DTm to DTn in FIG. 12A is similar to the traveling locus pattern from the measurement point DSm to DSn in FIG. Also, assuming that the latest measured vehicle position is DSn, as described above, from the data such as the travel distance and the road length, which position the vehicle is on the current route, that is, in FIG. It is possible to know where the road is located. From this, for example, the position of the vehicle on the road can be determined to be, for example, the left end DTn of the section ΔK. Thus, in the in-vehicle navigation device 100, the current position of the vehicle is displayed on the road of the map displayed on the display unit 106.
[0059]
By the way, in order to perform the map matching described above, the length of the route included in the route / guidance data of the peripheral area transmitted from the center device 150 is longer than the length of the travel locus held in the in-vehicle navigation device 100. It needs to be long. In view of this, in the second embodiment, a rectangular range including a route having a length that enables map matching by the in-vehicle navigation device 100 is set.
[0060]
(2) Range setting method according to this embodiment: The rectangular range setting processing according to this embodiment 2 will be described below with reference to the flowchart of FIG. 13 and FIG. This process is performed by the system control unit 152 of the center apparatus 150 and corresponds to step S6 in the flowchart of FIG.
[0061]
First, the length (distance) Lm of the approach path to the intersection extracted as the course change point is read from the database 153 (step S61). Next, the length Lm of this road is compared with the minimum distance Mmin that can be used for map matching (step S62). If Lm <Mmin, map matching cannot be performed by the in-vehicle navigation device 100, so the length Ln of the adjacent road is added to Lm.(Step S67). In such a calculation, the total road length is the minimum distance Mmin.AboveRepeat until.
[0062]
If this condition is satisfied, the total road length is now compared with a predetermined maximum distance Mmax (step S63). If the surrounding area is large, map matching is easy, but the data amount of route guidance transmitted from the center device 150 to the in-vehicle navigation device 100 also increases. Therefore, in order to prevent the amount of data necessary for map matching from being exceeded, such a limitation by the maximum distance Mmax is added. As a result of the comparison, the total road length is the maximum distance Mmax.More thanIf so, a temporary intersection is set at the position of the maximum distance Mmax (step S64). Then, a value obtained by doubling the distance between the temporary intersection and the course change point is set as a value of one side n of the rectangular range (step S66). Conversely, when the total road length is smaller than the maximum distance Mmax, a value obtained by doubling the linear distance between the starting intersection of the road and the route change point added last is set as the value of one side n of the rectangular range ( Step S68).
[0063]
The above processing will be described with reference to FIG. 14. In the case of FIG. 14A, the total length L2 + L3 of the roads R2, R3 is larger than the maximum distance Mmax. For this reason, a temporary intersection CK is set at the position of Mmax. Then, twice the linear distance Δn between the temporary intersection CK and the intersection C3 which is the course change point is the length n of one side of the peripheral area A1. Note that when the roads R2 and R3 are continuous in a straight line, n = Mmax × 2. On the other hand, in the case of FIG. 14B, the total length L2 + L3 of the roads R2, R3 is smaller than the maximum distance Mmax. For this reason, twice the linear distance Δm between the starting point intersection C1 of the road R2 and the intersection C3 which is the course change point is the length n of one side of the peripheral area A1. When roads R2 and R3 are continuous in a straight line, n = (L2 + L3) × 2.
[0064]
In the center device 150, when there is no intersection within the range of the minimum distance that can be matched with the map and the maximum allowable distance, a temporary intersection is set at the position of the maximum distance, and the course of the temporary intersection is changed. The length n of one side of the peripheral region is set using a linear distance from the point. On the other hand, when there is an intersection within the range of the minimum distance and the maximum distance, the length n of one side of the peripheral area is set using the linear distance between the intersection and the course change point. Further, guidance data for the surrounding area is transmitted to the in-vehicle navigation device 100 based on this value. By such processing, the vehicle-mounted navigation device 100 can perform map matching before the course change point. In addition, you may make it perform the same process about the escape route side of a course change point. Compare the values of n on the intrusion road side and the escape road side, and select the larger one.
[0065]
Embodiment 3
Next, a third embodiment of the present invention will be described. In this form 3, return route data is extracted and transmitted to the in-vehicle navigation device 100 so that the vehicle can return to the searched route even if the vehicle deviates from the route transmitted from the center device 150. is there. For example, as shown in FIG. 15, when the length of the road R3 is shorter than the guidance start distance GL of the course change point C3, guidance to C3 before the intersection C2, for example, “the next intersection is in the right direction” Voice guidance will be started. For this reason, the user (driver) on the vehicle side may turn right at the intersection C2. However, depending on road conditions, return route guidance data (at least drawing data of roads Ra and Rb in FIG. 15) is extracted and included in the route / guidance data so that the recommended route can be returned even if the route is incorrect. It is possible to transmit to the vehicle side.
[0066]
FIG. 16 shows a procedure of return path processing in the system control unit 152 of the center device 150. This process is performed, for example, between steps S61 and S62 in FIG. In the system control unit 152, it is determined whether or not the length L3 of the approach path R3 of the course change point C3 is greater than a predetermined guidance start distance GL (step S70). As a result, if L3 is larger than GL, there is no fear of changing the course at the intersection C2, so no return path is set (No in step S70). However, conversely, L3 is GLbelowWhen there is a possibility that the route is wrong, it is determined whether or not there is a return route (step S71). That is, it is determined whether or not a road that goes in the same direction as the escape route R4 of the route change point C3 is at the intersection C2 before the route change point C3.
[0067]
In the example of FIG. 15, there is a road Ra that branches from the route change point C3 in the same direction as the escape route R4 at the intersection C2 before the route change point C3. Therefore, the road Ra and another road Rb for returning to the searched route are set as the return route (step S72).
[0068]
In the above description, a route that branches from the intersection C2 before the route change point C3 and returns to the recommended route is extracted. However, as shown in FIG. 4, the route change point C3 is erroneously passed. The return path may be extracted. In the example in the figure, the intersection just after passing the route change point C3CgThe return paths Rc, Rd, and Re can be set. The return route data obtained in this way is also included in the route / guide data and transmitted to the in-vehicle navigation device 100.
[0069]
Embodiment 4
Next, a fourth embodiment of the present invention will be described. This form 4 relates to a display method of a simple map displayed in the middle of a route. As described above, detailed route guidance is not performed in the middle of the route excluding the area around the route change point, and simple display as shown in FIG. However, when performing route guidance from the departure point to the destination, providing the driver with the data of the next intersection to be changed next and the next intersection to be changed in advance is how and at which intersection in the future. This makes it possible to predict route changes that will change, which is extremely useful for safe driving. In general, the object can be sufficiently achieved by providing data on the course change points up to two points ahead. In this embodiment, a simple map in the middle of a route is to be obtained from such a viewpoint.
[0070]
FIG. 17 shows an example of a simple map according to this embodiment, and FIG. 18 shows a processing method for displaying a simple map. In the example of FIG. 17, there is an intersection Cb that is a course change point from a departure point Ca to La [km], and there is an intersection Cc that is a next course change point from this intersection Cb to Lb [km]. This display is a midway route from exiting the peripheral area of the departure point Ca to entering the peripheral area of the intersection Cb and from exiting the peripheral area of the intersection Cb to entering the peripheral area of the intersection Cc. It is what is displayed.
[0071]
In the arithmetic processing unit 101, the coordinate values (longitude / latitude) of the departure point Ca that is the display start point, the intersection Cb that is the next route change point, and the intersection Cc that changes the next route are read from the route / guidance data. . Then, each point is plotted on the longitude and latitude coordinates with reference to the coordinate values. Next, coordinate conversion for translation is performed so that the starting point Ca, which is the display starting point, is the origin of the coordinate system xy (lower case). For example,Point of departureIf the longitude and latitude coordinates of Ca are (x0, y0), the coordinate value on the coordinate system xy is (x, y) = (x0−x0, y0−y0) = (0, 0). Similar processing is performed for the intersections Cb and Cc. If the longitude and latitude coordinates of the intersection Cb are (xx1, yy1), the coordinate values on the coordinate system xy are (x1, y1) = (xx1-x0, yy1-y0). If the longitude and latitude coordinates of the intersection Cc are (xx2, yy2), the coordinate value on the coordinate system xy is (x2, y2) = (xx2).−x0, yy2−y0). In FIG. 18A, the position of each point on the xy coordinates and the path connecting them are indicated by bold lines.
[0072]
next,Point of departureAssuming a line segment Ha connecting Ca and the next intersection Cb, coordinate rotation (affine transformation) is performed so that this line segment is directed upward on the screen as shown in FIG. That is, a new coordinate system XY (upper case) with the line segment Ha as the Y-axis direction is set on the screen, and the coordinate transformation is performed by rotating the coordinate system xy by an angle θ.
[0073]
Since the starting point Ca is located at the center in any coordinate, the coordinate value is (0, 0). On the other hand, the coordinate values (X1, Y1) of the intersection Cb are
X1 = x1 · cosθ−y1 · sinθ (= 0), Y1 = x1 · sinθ−y1 ・ cosθ
It becomes. Similarly, the coordinate value (X2, Y2) of the intersection Cc is
X2 = x2 ・ cosθ−y2 · sinθ, Y2 = x2 · sinθ−y2 ・ cosθ
It becomes. θ is expressed by θ = arctan (x1 / y1), where the clockwise coordinate rotation direction is positive.
[0074]
Next, based on the coordinate values converted as described above, scaling is performed so that all these points are displayed in a predetermined area of the display screen. That is, the display position is set as follows, with the horizontal (X direction) and vertical (Y direction) sizes of the display area set to A and B, respectively, and the lower left corner of the display area as the coordinate origin. . If the display area is set a certain amount smaller than the displayable area of the screen, it is convenient for displaying characters such as intersection names. First, the starting point Ca (0, 0) that is the starting point is displayed as it is in (0, 0) of the display area (X, Y). The intersection Cc (X2, Y2) is set to (A, B), which is the upper right corner of the screen, in order to make maximum use of the display area. Next, the intersection Cb (X1, Y1) between them is set to (0, B · Y1 / Y2) in consideration of the scale. When the route of FIG. 18 (A) is displayed with such setting, it is as shown in FIG.
[0075]
In the case of the route as shown in FIG. 18B, when the starting point is brought to the origin of the display area (X, Y), the intersection Cd is outside the screen. Therefore, the starting point is (0, 0 translated in the Y direction and set to (0, | Y2 |). In this way, the intersection Cb is at the upper left corner of the display area, and the intersection Cd is at the lower right corner of the display area. When the display screen is shown, it is like a one-dot chain line frame in FIG.
[0076]
FIG. 18 shows a case where the second intersections are all present in the positive direction of the X-axis, but if they are present in the negative direction, the starting point may be moved to the right corner of the display area. For example, as shown in FIG. 18A, when the second intersection is Ce, the starting point Ca that is the starting point is displayed at (A, 0) in the lower right corner of the screen. The intersection Ce (-X3, Y3) is set to (0, B) at the upper left corner of the screen in order to make the most of the display area. Next, the intersection (X1, Y1) between them is set to (A, B · Y1 / Y2) in consideration of the scale.
[0077]
After determining the display position of the starting point and intersection as described above, each intersection is connected by line segments Ha and Hb according to the traveling direction, and each intersection name, intersection shape, distance between intersections, and branch direction are indicated. If necessary, the index to be used and the name of the road to be branched are displayed. Furthermore, if necessary, line segments and intersection names can be displayed, such as displaying red as the advance color if the distance between the intersections is within a predetermined range, and blue as the backward color if the distance is greater than or equal to the predetermined distance. Color code.
[0078]
The simple map creation process by the arithmetic processing unit 101 as described above is executed, for example, when it is determined that the vehicle has escaped from the area around the departure point or the route change point. That is, a simple map is created and displayed so as to include the following two course change points starting from the course change point passed immediately after.
[0079]
In addition, you may make it display all the searched processes with this simple map. For example, an intersection where the names of the approach route and the exit route are different at the route change point, an intersection judged to have a high probability of being mistaken in the route change direction (for example, an intersection that can be changed in the same direction) It is convenient to select and display an intersection consisting of a combination thereof.
[0080]
Moreover, you may combine such a whole process display and the partial process display shown in FIG. For example,
(1) The entire route is displayed near the departure point. At this time, the next course change point may be displayed.
(2) When approaching a course change point, display a partial stroke display.
(3) After exiting the area around the course change point, the entire process is displayed again. At this time, the route change point that has already passed may be deleted, and the next route change point may be displayed.
In this way, by switching between the full-stroke display and the partial-stroke display, the remaining full-stroke confirmation and the latest intersection confirmation can be performed alternately, and the whole and part of the searched route can be appropriately adjusted according to the vehicle's progress. I can grasp it.

Embodiment 5
Next, a fifth embodiment of the present invention will be described. In this embodiment, route / guidance data obtained as a result of a route search performed in the past is stored on the center side or the vehicle side. By using this stored data, the amount of data to be transmitted can be reduced.
[0081]
(1) When past route / guidance data is saved on the vehicle side .... The past route / guidance data is saved in the data storage unit 103. The vehicle-mounted navigation device 100 compares the current vehicle position measured by the position measurement unit 104 with the data stored in the data storage unit 103 to determine whether there is route / guidance data corresponding to the current position (see FIG. 8 step S130). This determination is made based on whether or not the current vehicle position is included in any of the areas around the course change point shown in FIG. 7D stored in the data storage unit 103. For example, in the example shown in FIG. 4, the surrounding areas A1, A2, A3 and the vehicle current position are compared.
[0082]
As a result, when it is determined that there is a peripheral area corresponding to the current vehicle position and there is corresponding route / guidance data, the route / guidance data is used. For example, as shown in FIG. 4, when moving from the departure point PD to the destination PA and then moving from the PA to another PC (not shown), the route / guide data of the area around the PA is The data is stored in the data storage unit 103 when searching for a route from the first PD to the PA. Therefore, it is sufficient to use the stored data, and there is no need to newly acquire route / guide data from the center side. On the other hand, if it is determined that there is no corresponding route / guidance data, a flag for requesting route / guidance data corresponding to the current vehicle position is set (step S131).
[0083]
This flag is transmitted to the center device 150 together with the departure point data and destination data. In the center apparatus 150, the presence or absence of this flag is referred to by the system control unit 152. If there is no flag, the corresponding route / guidance data is not transmitted, and if there is a flag, all the extracted route / guidance data is transmitted. On the other hand, in the in-vehicle navigation device 100, the route / guidance data transmitted from the center device 150 and the route / guidance data stored in the data storage unit 103 are combined by the arithmetic processing unit 101, as shown in FIG. Constructed as continuous route / guide data. By doing in this way, the amount of data transmitted from the center side to the vehicle side can be reduced without causing trouble in route guidance.
[0084]
(2) When past route / guidance data is saved on the center side and the vehicle side .... The past route / guidance data is saved in the data storage unit 103 on the vehicle side, and the user is stored in the database 153 on the center side. It is held with the ID. In the center device 150, the stored data of the user with the corresponding ID is referred to before transmission of the route / guidance data in step S9 of FIG. Then, only route / guidance data that is not stored on the vehicle side is transmitted. This method can similarly reduce the amount of data to be transmitted.
[0085]
[Other Embodiments]
The present invention has many embodiments and can be variously modified based on the above disclosure. For example, the following are included.
[0086]
(1) The road data, the intersection data, and the area guidance data shown in the above embodiment are examples, and may be appropriately changed as necessary. Further, the format of the data may be changed as appropriate.
[0087]
(2) In the above embodiment, all of the route / guidance data extracted at the start of route guidance is transmitted from the center side to the vehicle side. However, the data is divided into a plurality of pieces and transmitted according to the traveling position of the vehicle. You may make it do. When the departure point and the destination are very far away, the route / guidance data is also considerable. By dividing and transmitting this, the data storage capacity in the in-vehicle navigation device can be reduced.
[0088]
(3) In the said form, it is supposed that the guidance data of a surrounding area are transmitted not only about a course change point but also about a departure place and a destination. However, there are cases where guidance data is not necessarily required for the departure point and the destination, such as when the home is the destination. Therefore, the surrounding guidance data may not be transmitted for these departure points and destinations, and the surrounding guidance data may be transmitted only for the route change point on the way. Further, the user may select the area guidance data as necessary.
[0089]
(4) Data obtained from VICS or the like may be added to the route / guide data transmitted from the center side. Even if the VICS information is considered at the time of generating the route / guidance data on the center side, the road situation may change when the vehicle actually travels. Therefore, it is convenient to receive the VICS information on the vehicle side during traveling and use it for route guidance.
[0090]
(5) Although the said form applies this invention to a vehicle, it is applicable to various mobile bodies, such as a portable mobile terminal.
[0091]
【The invention's effect】
As described above, the present invention has the following effects.
(1) Since the guidance data corresponding to the area around the route change point is extracted from the guidance data on the searched route and transmitted to the moving side, the amount of data transmitted from the center side to the moving side can be reduced. Can be planned.
(2) Since the guidance data is extracted in the vicinity of the route change point which is the main part on the searched route, the route guidance can be performed satisfactorily even if the amount of data transmitted to the moving side is reduced.
(3) Since data necessary for route guidance is transmitted from the center device, the moving side does not need to have route data, search data, and guidance data, and the device can be simplified.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration according to an embodiment of the present invention.
FIG. 2 is a diagram showing the contents of road data and intersection data stored in a database of the center device.
FIG. 3 is a flowchart showing the operation of the center device.
FIG. 4 is a diagram illustrating an example of a searched route.
FIG. 5 is a diagram showing data contents of a searched route.
FIG. 6 is a diagram illustrating a method for extracting a course change point.
FIG. 7 is a diagram showing the contents of route / guidance data transmitted to the in-vehicle navigation device.
FIG. 8 is a flowchart showing the operation of the in-vehicle navigation device.
FIG. 9 is a flowchart showing the operation of the in-vehicle navigation device.
FIG. 10 is a diagram illustrating an example of a route schematic diagram and an example of a map corresponding to a peripheral area of a departure place.
FIG. 11 is a diagram illustrating an example of a display in the middle of a route and an example of an enlarged intersection display.
FIG. 12 is a diagram illustrating an example of map matching.
FIG. 13 is a flowchart showing a technique for setting a peripheral region capable of map matching.
FIG. 14 is a diagram illustrating a technique for setting a peripheral region in which map matching is possible.
FIG. 15 is a diagram illustrating a technique for setting a return path.
FIG. 16 is a flowchart showing a method for setting a return path.
FIG. 17 is a diagram showing an example of a simple map displayed in the middle of a route.
FIG. 18 is a diagram illustrating a method for creating a simple map.
[Explanation of symbols]
100: In-vehicle navigation device
101 ... arithmetic processing unit
102: Program storage unit
103: Data storage unit
104: Position measuring unit
105 ... Input unit
106 ... Display section
107: Audio output unit
108: Transmitter / receiver
150 ... Center device
151. Communication control unit
152 ... System control unit
153 ... Database
154: Position correction unit
A1 to A4 ... Peripheral area
Ca ... Departure
Cb-Ce, Cp-Cr ... Intersection
C1-C8 ... intersection
CK ... Temporary intersection
DS ... Measurement point
DT ... Node point
GL ... Guidance start distance
M ... Intersection
MA-ME ... mark
MF ... Background image
MG ... Distance display
PA ... Destination
PD ... From
R1-R9 ... Road
Ra to Re: Return path
ΔK ... Section

Claims (8)

A navigation center device for providing road data and guidance data necessary for route guidance from a departure place to a destination for a navigation device having no means and data for performing a route search,
Data storage means for storing road data and route guidance data;
Receiving means for receiving data relating to a starting point and a destination from the navigation device;
Using the data stored in the data storage means, route search means for performing a route search based on the data received by the receiving means;
A route change point extracting means for extracting a route change point on the route searched by the route search means;
A surrounding area setting means for setting a surrounding area around the course changing point extracted by the course changing point extracting means;
Guidance data acquisition means for obtaining route guidance data in the peripheral area set by the peripheral area setting means from the data storage means;
Transmission means for transmitting the road data of the route searched by the route search means and the route guidance data in the peripheral area obtained by the guidance data acquisition means to the navigation device, respectively;
A navigation center device comprising:   The navigation center device according to claim 1, wherein the route search means performs route search by correcting current position data transmitted from the navigation device.   2. The navigation center device according to claim 1, wherein the route change point is extracted in consideration of an angle between an approach route and an exit route.   The navigation center device according to claim 1, wherein the peripheral area is set as a rectangular range centered on the route change point and one side of which is orthogonal to the approach route at the route change point.   2. The navigation center device according to claim 1, further comprising return route search means for searching for a return route from the approach route side to the exit route side of the route change point in a corresponding peripheral region. Data storage means for receiving and storing data transmitted from the navigation center device according to any one of claims 1 to 5 ,
Position measuring means for measuring the current position;
A route guidance unit that reads out data of the peripheral area corresponding to the measurement result thereby from the data storage unit, and performs route guidance based on the data,
A navigation device characterized by comprising: Using the data stored in the data storage means, comprising simple map creation means for creating a simple map for route guidance in the middle of the route other than the surrounding area, the route guidance means comprising the simple map creation 7. The navigation apparatus according to claim 6 , wherein a simple map created by the means is displayed in correspondence with a measurement result by the position measuring means. The navigation apparatus according to claim 6 or 7, wherein the apparatus is provided in a vehicle or a portable mobile terminal.

Images