JP2005069770A - Navigation device and route guidance method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a navigation device and a route guidance method capable of performing route guidance even at the communication fault time. <P>SOLUTION: In this navigation device 3, route guidance data based on routes determined by dividing a route from the starting place to the destination into each prescribed section are acquired successively from an external device corresponding to the traveling state of a vehicle, and the route guidance is performed, while displaying the first display screen on a display device 32 based on the acquired each route guidance data. When acquiring the route guidance data, data for displaying the second display screen having fewer display contents than that of the first display screen in a route in a wider range than the divided section are acquired, and display on the first display screen is discontinued and the second display screen is displayed at the communication fault time. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a navigation device and a route guidance method.

  2. Description of the Related Art Conventionally, map information used for a navigation device can be acquired through an information center such as a server due to advances in communication technologies such as Internet communication and mobile communication. Thus, by acquiring map information by communication, it becomes unnecessary to purchase storage media, such as DVD which recorded map information, and the newest map information can be obtained.

  However, there is no problem if the map information is requested from the information center and the map information can be acquired from the information center. However, when radio waves are interrupted in buildings or tunnels, or when communication traffic increases. Because there is no communication with the information center, there is a problem that map information cannot be acquired. As a conventional technique for reducing such problems, a navigation device described in Patent Document 1 has been proposed.

  The navigation device described in Patent Document 1 requests a high-accuracy map from the information center and displays the high-accuracy map on a predetermined display device when approaching an adjacent area of the destination when performing route guidance. When a high-accuracy map cannot be acquired from the information center due to inability to communicate, a map with reduced accuracy is requested from the information center, and the map with reduced accuracy is displayed on the display device to guide the user to the destination. That's it.

Japanese Patent Laid-Open No. 2003-4468

  However, if a pedestrian uses a mobile phone to receive map information and provides route guidance, even if communication with the information center is interrupted, it can continue by stopping and reconnecting to the information center. Map information can be obtained. However, in the in-vehicle navigation device, since the vehicle is moving at a high speed, even if communication is interrupted, it is impossible to stop suddenly and establish a connection with the information center again.

  Also, in places where the radio wave condition is poor such as in a tunnel, it is possible to cope by predicting that communication will be interrupted and acquiring map information of the corresponding area from the information center in advance. In the case of a communication failure due to a change or an increase in communication traffic, since it is impossible to predict these, map information cannot be acquired at the time of communication failure. For this reason, in order to guide the user to the destination, there is a problem that the user must have map information on his / her own.

  Therefore, the present invention has been made to solve these problems, and an object of the present invention is to provide a navigation device and a route guidance method that can perform route guidance even when a communication failure occurs.

  In order to solve the above-described problems, the navigation device of the present invention sequentially receives route guidance data corresponding to a route obtained by dividing a route from a departure point to a destination for each predetermined section from an external device according to the progress of the vehicle. A navigation device that obtains route guidance while displaying a first display screen on a predetermined display device based on each obtained route guidance data, and when the route guidance data is obtained, Data for displaying a second display screen that is a route to the ground and that has a smaller display content than the first display screen is acquired, and the display of the first display screen is interrupted when a communication failure occurs. And a means for displaying the second display screen.

  According to the present invention, during the route guidance, for example, even when a communication failure occurs due to an increase in communication traffic or a change in the radio wave environment, the route guidance cannot be performed on the first display screen. Since the display screen is displayed, route guidance can be performed even when there is a communication failure, so the driver's anxiety can be reduced.

  Further, the present invention is characterized in that, in the above configuration, the means displays at least one of a road name, a traveling direction, and a place name on the route on the second display screen. According to the present invention, it is possible to aim at a destination while referring to a road name, a traveling direction, and a place name in the middle of a route, so that driver's anxiety can be reduced.

  Further, the present invention is characterized in that, in the above configuration, the means displays the road name already displayed on the first display screen in the second display screen. According to the present invention, since the road name displayed on the first display screen is displayed on the second display screen, the route that has already been taken can be grasped.

  Further, the route guidance method of the present invention sequentially obtains route guidance data corresponding to a route obtained by dividing the route from the departure point to the destination for each predetermined section from the external device according to the progress of the vehicle. A route guidance method for performing route guidance while displaying a first display screen on a predetermined display device based on each route guidance data, and when obtaining the route guidance data, a route from the departure place to a destination And a first step of acquiring data for displaying a second display screen with less display content than the first display screen, and interrupting the display of the first display screen in the event of a communication failure And a second step of displaying the second display screen.

  According to the present invention, even when a communication failure occurs during route guidance due to, for example, an increase in communication traffic or a change in the radio wave environment, the route guidance cannot be performed on the first display screen. Since it is possible to compensate for the incapacitating state, the driver's anxiety can be reduced.

  Further, the present invention is characterized in that, in the above configuration, the second step displays at least one of a road name, a traveling direction, and a place name in the middle of the route on the second display screen. To do. According to the present invention, it is possible to aim at a destination while referring to a road name, a traveling direction, and a place name in the middle of a route, so that driver's anxiety can be reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the navigation apparatus and route guidance method which can perform route guidance even at the time of a communication failure can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described.

  FIG. 1 is a configuration diagram of a system according to the present embodiment. The system 1 includes a vehicle 2, a navigation device 3 mounted on the vehicle 2, a GPS satellite 4, a telephone network 5, a provider 6, an IP network 7, and an information center server 8.

  The navigation device 3 requests the map data corresponding to the position of the vehicle 2 to the information center server 8 via the telephone network 5, the provider 6, and the IP network 7 with a mobile phone, and the map sent from the information center server 8 Route guidance based on data. The telephone network 5 includes a mobile network and a public network. The provider 6 is for connecting the navigation device 3 to the information center server 8.

  The information center server 8 includes a database for storing various data such as route search data and map data, and route guidance data for route guidance from the departure point to the destination in response to a request from the navigation device 3. (Arrow navigation display data) is divided into predetermined sections and provided to the navigation device 3.

  The navigation device 3 sequentially acquires the data for arrow navigation display divided from the information center server 8 and performs route guidance while displaying a first display screen (arrow navigation display screen) on a display device described later. Further, when the information center server 8 provides the divided arrow navigation display data to the navigation device 3, the second display screen is a route from the departure point to the destination and has less display content than the arrow navigation display screen. Data (simple display data) for displaying (simple display screen) is provided to the navigation device 3.

  Since the navigation device 3 interrupts the display of the arrow navigation display screen at the time of communication failure and displays the simple display screen based on the simple display data acquired in advance, the navigation device 3 can provide route guidance through the simple display screen even at the time of communication failure. Can do. Thereby, the driver's anxiety can be reduced.

  The timing for providing the simple display data to the navigation device 3 is preferably provided when the divided arrow navigation display data is first provided to the navigation device 3, and the simple display data is provided to the navigation device 3. The timing to do may be at any time.

  Here, the arrow navigation display data includes information on node information, intersection identification flags, intersection names, road names, destination names, leaf data, arrows, and the like. The simple display data includes information on road names, traveling directions, place names along the route, and the like. The simple display data is preferably composed only of text data. The information center server 8 may be directly connected to the telephone network 5 so as to communicate with the navigation device 3 without going through the Internet.

  Next, the navigation device 3 will be described. FIG. 2 is a block diagram of the navigation device 3. The navigation device 3 includes a navigation control unit 31 that controls the entire navigation device 3, a display device 32 that displays a map, a menu, and the like, and a speaker 33 for voice guidance. The navigation device 3 is connected to a mobile phone 46.

  The navigation control unit 31 includes a CPU (Central Processing Unit) 35, a ROM (Read Only Memory) 36, a RAM (Random Access Memory) 37, an operation unit 38, a voice guidance control unit 39, an image drawing unit 40, a communication interface 41, a GPS. A receiver 42, a gyro 43, and a traveling pulse detection sensor 44 are provided. These are connected via a bus 45.

  The CPU 35 controls the entire navigation device 3. In addition, when the CPU 35 acquires the arrow navigation display data and the simple display data from the information center server 8, the CPU 35 writes them in a predetermined area of the RAM 36.

  The ROM 36 stores various control programs including a route guidance program. The RAM 37 is used as a work memory for the CPU 35 and stores arrow navigation display data and simple display data downloaded from the information center server 8. The operation unit 38 includes various switches and performs operation input. The voice guidance control unit 39 controls the speaker 33 when performing voice guidance.

  The image drawing unit 40 generates a map image based on the leaf data acquired from the information center server 8, and displays the generated map image on the screen of the display device 32. The image drawing unit 40 reads the arrow navigation display data sent from the information center server 8 from the RAM 37, generates an image for arrow navigation display, and displays the arrow navigation display screen on the display device 32.

  Further, the image drawing unit 40 reads from the RAM 37 simple display screen display data for displaying a simple display screen having a display content smaller than that of the arrow navigation display screen acquired when the arrow navigation display data is acquired. And a simple display screen is displayed on the display device 32.

  The communication interface 41 is connected to a GPS receiver 42, a gyro 43, a travel pulse detection sensor 44, and a mobile phone 46. The GPS receiver 42 receives a signal from the GPS satellite 4 and measures the absolute position of the vehicle. The gyro 43 is for detecting the direction of the vehicle. The travel pulse detection sensor 44 detects a pulse generated at every predetermined travel distance and measures the travel distance.

  Next, the guidance route provided by the information center server 8 will be described. FIG. 3 is a diagram for explaining a guide route provided by the information center server 8. In FIG. 3, a guide route IRT from the departure point A to the destination B is shown. Further, symbol A indicates a departure point, B indicates a destination, a solid line indicates a guide route, and each black circle indicates a node.

In the guidance route shown in FIG. 3, the vehicle departs from the departure point A, passes through the nodes N ₁ and N ₂ of the “National road XX line”, turns right at the node N ₃ that is “XX intersection”, and then turns to the node N _4. turn left through a plurality of nodes, further turn right node N _i, enters a "national road ×× line" shows an example of reaching the destination B through a plurality of nodes. The information center server 8 performs a route search as shown in FIG. 3 in response to a request from the navigation device 3.

Next, arrow navigation display data will be described. FIG. 4 is a diagram for explaining arrow navigation display data, which corresponds to the route search result of the information center server shown in FIG. As shown in FIG. 4, the arrow navigation data includes (1) position information (longitude and latitude) of all nodes N _{0 to} N _m on the guide route IRT, (2) an intersection identification flag, (3) an intersection name, ( 4) Includes road names.

The node N ₀ is the departure place A, the intersection identification flag is “0”, and the road name is “National road XX line”. The nodes N ₁ and N ₂ have an intersection identification flag “0”. In the node N _3, the intersection identification flag is “1”, and the intersection name is “XX intersection”. In the node _Ni, the intersection identification flag is “1”, the intersection name is “ΔΔ intersection”, and the road name is “national road ×× line”.

The node N _m is a destination, and the intersection identification flag is “0”. A node with an intersection identification flag “1” indicates that there is an intersection, and a node with an intersection identification flag “0” indicates that there is no intersection. The navigation device 3 displays the arrow navigation display screen on the display device 32 by acquiring the data for arrow navigation display shown in FIG. 4 from the information center server 8.

  Next, the display method of the arrow navigation display screen and the simple display screen will be described with reference to FIGS. FIG. 5 is a diagram showing a search route from the departure point A to the destination B. When a route guidance request from the departure point A to the destination B is input via the operation unit 38 of the navigation device 3, the information center server 8 searches for a guidance route as shown in FIG.

  FIG. 6 is a view showing a display example of the arrow navigation display screen. In FIG. 6, reference numeral 3 denotes a navigation device, and 32 denotes a display device. As shown in FIG. 6, the traveling direction, the distance to the intersection, the direction of turning at the intersection, and the destination B are displayed on the arrow navigation display screen (first display screen). The navigation device 3 displays an arrow navigation display screen as shown in FIG. 6 on the display device 32 when no communication failure has occurred.

  Next, a display example of the simple display screen will be described. FIG. 7 is a diagram showing a display example of a simple display screen. As shown in FIG. 7, on the simple display screen, only the road names “National Route 4”, “Prefectural Road 521”, and “Destination B” are displayed. When a communication failure occurs, the navigation device 3 displays a simple display screen as shown in FIG. 7 on the display device 32 based on the data for simple display acquired in advance. Even if the arrow navigation display screen cannot be displayed on the simple display screen, route guidance can be performed, so that the driver's anxiety can be reduced.

  In addition, the road name is added to the display data for arrow navigation, the route digestion state is calculated by comparing with the route information when the route search is performed, and the name of the road that has already passed at the time of communication failure is displayed on the simple display screen. You may do it. As a result, the driver can grasp the route that has already been taken.

  FIG. 8 is a diagram for explaining display switching when a communication failure occurs. In FIG. 8, reference numeral A denotes a departure place, B denotes a destination, P denotes a location where a communication failure has occurred, 32 denotes a display device, and 32 a denotes a screen of the display device 32. Further, FIG. 8 shows an example in which a route is selected from the departure point A to reach the destination B through “National road 6”, “National road 4”, and “Prefectural road 521”. .

  The navigation device 3 displays an arrow navigation display screen on the display device 32 based on the arrow navigation display data provided from the information center server 8 from the departure point A to the communication failure occurrence point P. In the first section of the guide route, the first navigation device 3 displays “straight arrow”, “5 km”, and “left turn arrow” on the screen 32 a of the display device 32, In the section, the characters “straight arrow”, “1 km”, and “right turn arrow” are displayed on the screen 32a of the display device 32. In the third section, “straight arrow”, “10 km” are displayed. The character, “left turn arrow”, is displayed on the screen 32 a of the display device 32.

  After passing the communication failure occurrence point P, the navigation device 3 switches to a simple display screen and displays the characters “National Route 4”, “Prefectural Road 521”, and “Destination: B” on the screen 32a of the display device 32. To do. Thus, since the navigation device 3 displays a simple display screen when the arrow navigation display screen cannot be displayed, the navigation device 3 can compensate for a state in which the guidance cannot be recovered until the communication failure is recovered. Can be reduced.

  FIG. 9 is a diagram for explaining display switching when a communication failure occurs. (A) is a diagram showing a route, (b) is a diagram showing an arrow navigation display screen, (c) is a diagram showing a first simplified display screen, and (d) is a second simplified display screen. It is a figure which shows an example. As shown in FIG. 9 (a), the guidance route starts from the departure point A and reaches the destination B through "National highway 6", "National highway 4", and "Prefectural road 521". Being explored.

  As shown in FIG. 5B, when displaying the arrow navigation display screen, the navigation device displays “straight arrow”, “5 km” characters, “left turn arrow” in the first section from the left, and “left turn arrow” in the second section. , “Straight arrow”, “5 km”, “right turn arrow”, in the third section “straight arrow”, “10 km”, “left turn arrow”, in the fourth section, “straight arrow”, The characters “1 km”, “Right turn arrow”, “Line arrow”, “5 km”, “Left turn arrow” in the fifth section, “Line arrow”, “Destination B” in the sixth section Display each character.

  Further, as shown in FIG. 5C, when the navigation apparatus 3 displays the first simplified screen, the “starting place A”, “National highway 6”, “National highway 4” are displayed in the first section from the left. In the second section, the characters “National highway No. 6,” “National highway No. 4,” and “Prefectural road 521” are used, and in the third section, “National highway No. 4,” “Prefectural road 521,” and “Destination B”. In the fourth section, the characters “National Route 4”, “Prefectural Road 521” and “Destination B” are used. In the fifth section, the characters “Prefectural Road 521” and “Destination B” are displayed. In the section, “Destination B” is displayed.

  Further, as shown in FIG. 4D, when the navigation apparatus 3 displays the second simplified screen, the character “XX” is displayed in the first section from the left, and “XX” is displayed in the second section. "Direction", "Ox direction", in the third section, "Ox direction", "△ □ direction" characters, and in the fourth segment, "X direction", "△ □ direction" characters In the fifth section, the characters “Δ □ direction” and “B direction” are displayed, and in the sixth section, the characters “B direction” are displayed.

  When the navigation device 3 can acquire the data for arrow navigation from the information center server 3, the navigation device 3 displays the arrow navigation display screen on the display screen as shown in the first to third sections in FIG. In the fifth and sixth sections after a communication failure occurs at a point, simple display such as the first simple display screen and the second simple display screen is performed based on the simple display data acquired from the information center server 8 in advance. As a result, it is possible to make up for the inability to guide until the communication failure is recovered, and to reduce the driver's anxiety. Note that the arrow navigation display screen, the first simple display screen, and the second simple display screen may be switched by operating the operation unit 38.

  Next, the operation of the system according to the present embodiment will be described. FIG. 10 is a diagram illustrating an operation flowchart of the system according to the present embodiment. In step S101, the CPU 35 determines whether or not there is a route search request by operating the operation unit 38 of the user. If there is a route search request, the process proceeds to step S102, and the mobile phone 46 is passed through in step S102. Then, a route acquisition request including information such as the vehicle position and destination is transmitted to the information center server 8.

  In step S103, when the information center server 8 receives the route acquisition request from the navigation device 3, the information center server 8 proceeds to step S104, performs a route search according to the route acquisition request with reference to the database, and is shown in FIG. 3 and FIG. Create route information from the starting point to the destination. In step S105, the information center server 8 divides the route from the departure place to the destination after a predetermined section. For example, as shown in FIG. 9, the route from the departure place to the destination is divided into six sections such as a first section to a sixth section.

  In step S106, the information center server 8 refers to the route and database divided in step S105, creates arrow navigation display data and simple display data of all routes, and transmits the generated data to the navigation device 3. At this time, the information center server 8 creates the data of the first divided portion in the divided route for the arrow navigation display data, and the remaining arrow navigation display data corresponds to the current position information sent from the navigation device 3. Create sequentially in divided units. On the other hand, the simple display data is not created for each divided route, but data for all routes is created.

  In step S <b> 107, when the CPU 35 receives the arrow navigation display data for the first section and the simplified display data for all routes, the CPU 35 stores them in a predetermined area of the RAM 36. In step S108, the image drawing unit 40 generates an arrow navigation display image based on the arrow navigation display data for the first section stored in the RAM 36, and displays the image on the display device 32 in FIGS. ) Display an arrow navigation display screen as shown in the first section. At this time, the CPU 35 calculates the distance to the intersection using the current position of the vehicle 2 and the intersection position. When the vehicle 2 approaches the intersection, the voice guidance control unit 39 passes the speaker 33 to the intersection. Distance guidance, intersection guidance such as left turn, right turn, straight ahead at the intersection, etc. is performed by voice.

  The CPU 35 requests the information center server 8 to transmit the next arrow navigation display data while monitoring the position of the vehicle 2 every predetermined period, acquires the next arrow navigation display data from the information center server 8, and acquires the RAM 37. Is stored in a predetermined area. The image drawing unit 40 generates an arrow navigation display image based on the arrow navigation display data of the next section, and displays an arrow navigation display screen as shown in the second section of FIG. 9B on the display device 32.

  In step S109, the CPU 35 monitors the output from the communication interface 41 every predetermined period, determines whether a communication failure has occurred with the information center server 8, and determines that no communication failure has occurred. Proceeds to step S113, and if it is determined that a communication failure has occurred, the process proceeds to step S110.

  In step S110, the image drawing unit 40 reads out simple display data for all paths stored in a predetermined area of the RAM 37 based on an instruction from the CPU 35, generates an image for simple display, and displays the image on the display device 32 as shown in FIG. Alternatively, a simple display screen as shown in FIGS. 9C and 9D is displayed.

  In step S111, the CPU 35 monitors the output from the communication interface 41 every predetermined period, determines whether communication with the information center server 8 is established, and performs communication with the information center server 8. If it is determined that it has not been established, the process returns to step S110, and the display of the simple display screen on the display screen 32 is maintained.

  On the other hand, if the CPU 35 determines in step S111 that communication with the information center server 8 has been established, the CPU 35 outputs a control signal to the image drawing unit 40. In step S112, the image drawing unit 40 reads the arrow navigation display data sent from the information center server 8 from the RAM 37, generates an image for arrow navigation display, and displays the fifth image in FIG. An arrow navigation display image as shown in the section is displayed. In step S113, the CPU 35 determines whether the vehicle 2 has arrived at the destination based on the vehicle position information from the communication interface 41, and determines that the vehicle 2 has arrived at the destination. End the guidance display.

  According to the present embodiment, even when a communication failure occurs during route guidance due to, for example, an increase in communication traffic or a change in radio wave environment, route guidance cannot be performed on the arrow navigation display screen. Since the display is made, it is possible to compensate for the inability to guide until recovery from the communication failure, so the driver's anxiety can be reduced.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims.・ Change is possible.

1 is a configuration diagram of a system according to an embodiment. It is a block diagram of a navigation apparatus. It is a figure for demonstrating the guidance which an information center server provides. It is a figure for demonstrating the data for arrow navigation. It is a figure which shows all the paths from the departure place A to the destination B. It is a figure which shows the example of a display of an arrow navigation display screen. It is a figure which shows the example of a display of a simple display screen. It is a figure for demonstrating display switching when a communication failure generate | occur | produces. It is a figure for demonstrating display switching when a communication failure generate | occur | produces. It is a figure which shows the operation | movement flowchart of the system which concerns on a present Example.

Explanation of symbols

2 Vehicle 3 Navigation Device 8 Information Center Server 31 Navigation Control Unit 32 Display Device 33 Speaker 35 CPU
36 ROM
37 RAM
38 Operation Unit 39 Voice Guidance Control Unit 40 Image Drawing Unit 41 Communication Interface

Claims (5)

Route guidance data corresponding to a route obtained by dividing the route from the departure point to the destination for each predetermined section is sequentially obtained from an external device according to the progress of the vehicle, and a predetermined display device is obtained based on the obtained route guidance data. A navigation device that provides route guidance while displaying the first display screen on the screen,
When obtaining the route guidance data, obtain data for displaying a second display screen that is a route from the departure place to the destination and that has less display content than the first display screen, A navigation device comprising means for interrupting display of the first display screen and displaying the second display screen when a communication failure occurs. The navigation device according to claim 1, wherein the means displays at least one of a road name, a traveling direction, and a place name in the middle of the route on the second display screen. The navigation device according to claim 1, wherein the means displays the road name already displayed on the first display screen in the second display screen. Route guidance data corresponding to a route obtained by dividing the route from the departure point to the destination for each predetermined section is sequentially obtained from an external device according to the progress of the vehicle, and a predetermined display device is obtained based on the obtained route guidance data. A route guidance method for performing route guidance while displaying the first display screen on the screen,
When acquiring the route guidance data, a data for displaying a second display screen that is a route from the departure place to the destination and that has less display content than the first display screen is acquired. 1 step,
And a second step of interrupting the display of the first display screen and displaying the second display screen when a communication failure occurs. 5. The route guidance method according to claim 4, wherein in the second step, at least one of a road name, a traveling direction, and a place name in the middle of the route is displayed on the second display screen.

Images