JP3708372B2 - Route display method for in-vehicle navigation system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a route display method for an in-vehicle navigation device that guides a vehicle to a destination along a guidance route, and more particularly, to a route display method for an in-vehicle navigation device that makes it easy to see the road state ahead of the traveling direction of the vehicle.
[0002]
[Prior art]
The vehicle-mounted navigation device includes a map data storage device such as a CD-ROM or DVD-ROM (hereinafter simply referred to as “CD-ROM”) on which map data is recorded, a display device, a GPS (Global Positioning System) receiver, It has a sensor for detecting the current position and current direction of the vehicle, such as a gyro and a vehicle speed sensor, reads out map data including the current position of the vehicle from the map data storage device, and a map around the vehicle position based on the map data While drawing the image on the display screen, the vehicle position mark (location) is displayed superimposed on the display screen, the map image is scrolled and displayed as the vehicle moves, and the map image is fixed on the screen and the vehicle position mark is displayed. Or move it so that you can see at a glance where the vehicle is currently driving.
[0003]
In general, the in-vehicle navigation device is equipped with a route guidance function that allows the user to easily travel to a desired destination without making a mistake on the road. According to this route guidance function, the lowest cost route connecting from the starting point to the destination using map data is automatically searched by performing simulation calculation such as horizontal search method or Dijkstra method, and the searched route is guided. Memorize it as a route and draw a guidance route on the map image with a different color from other roads and display it on the screen while driving, or a fixed distance to the intersection where the vehicle should change the route on the guidance route When the user approaches the inside, the user is guided to the destination by drawing an arrow indicating the route at the intersection where the route on the map image should be changed and displaying it on the screen.
[0004]
Cost is based on distance, road width, road type (general road or highway, etc.), a value multiplied by a constant according to right turn and left turn, etc., estimated travel time of vehicle, etc. The degree of appropriateness as a numerical value. Even if there are two routes with the same distance, the cost differs depending on whether the user uses a toll road or not, whether to prioritize travel distance or travel time, etc. Become.
[0005]
Maps stored in a map data storage device such as a CD-ROM have the appropriate longitude and latitude width according to the scale level such as 1/12500, 1/25000, 1/50000, and 1/100000. The roads and the like are stored as coordinate sets of vertices (nodes) expressed by longitude and latitude. A road is formed by connecting two or more nodes, and a portion connecting two nodes is called a link.
[0006]
In-vehicle navigation devices generally display a map by a display method called north up that displays north on the upper side and a display method called head up that displays the traveling direction of the vehicle on the upper side. There is also a display method called front wide that displays the vehicle position shifted from the center of the screen so that the traveling direction of the vehicle is widely displayed. Front wide is used in combination with North Up or Front Up.
[0007]
[Problems to be solved by the invention]
When a map is displayed in front wide, for example, as shown in FIG. 11, a map image, a vehicle position mark 30, and a guidance route (indicated by broken line arrows in the figure) are displayed. In this case, if the road is a road with two or more lanes on one side, it may be difficult to determine which lane to drive after turning right at the intersection. For example, when the guidance route is shown in FIG. 12 (a), it is necessary to turn to the right and then travel on the left lane. Further, when the guidance route is shown in FIG. 12B, it is necessary to drive the right lane after turning right at the intersection.
[0008]
Accordingly, an object of the present invention is to provide a route display method for an in-vehicle navigation device that displays as many guidance routes as possible and easily confirms the state of the road ahead of the vehicle.
[0009]
[Means for Solving the Problems]
In the route display method of the in-vehicle navigation device that guides the vehicle to the destination along the guidance route, the above-described problem is: (a) determining the size of the vehicle position mark display range; and (b) determining the current position of the vehicle. The position of the vehicle position mark display range is determined so as to include, and (c) the i th (where i is a variable) guidance in the vehicle position mark display range in front of the current position of the vehicle and the traveling direction of the vehicle It is determined whether or not the route node is included. (D) When it is determined that the route node is included, the value of i is incremented and the processing from (c) is continued. When it is determined that the route node is not included, (e ) By changing the position of the vehicle position mark display range, it is determined whether or not the current position of the vehicle and the i-th guidance route node are included in the vehicle position mark display range; Judged to be When the vehicle position mark is displayed, the position of the vehicle position mark display range is changed, the value of i is incremented, and the processing from (c) is continued. The problem is solved by the route display method of the in-vehicle navigation device, wherein the range of the map to be displayed on the display device is determined in accordance with the position of the range.
Further, the above-described problems are: (a) the size of a vehicle position mark display range is determined in a route display method of an in-vehicle navigation device that guides a vehicle to a destination along a guidance route, and (b) the vehicle position. A calculation range based on the current position of the vehicle is determined according to the size of the mark display range, and (c) a guidance route node that is ahead of the vehicle in the traveling direction and is included in the calculation range is extracted. (D) Finding the position of the vehicle position mark display range that includes the current position of the vehicle and that contains the largest number of extracted guidance route nodes, and (e) displays the position according to the position of the vehicle position mark display range. The problem is solved by a route display method for a vehicle-mounted navigation device, wherein the range of a map to be displayed on the device is determined.
[0010]
The operation of the present invention will be described below.
In the present invention, first, the size of the vehicle position mark display range is determined. In order to confirm the road condition ahead of the vehicle traveling direction, it is preferable to display as many guidance routes as possible in front of the vehicle traveling direction. However, if the vehicle position mark is arranged at the end of the screen, the current position of the vehicle is displayed. It becomes difficult to grasp the surrounding road conditions. For this reason, the vehicle position mark display range is determined in a range smaller than the entire range displayed on the screen so that the vehicle position mark does not become an end portion of the screen.
[0011]
Thereafter, the position of the vehicle position mark display range is determined so as to include the most guidance routes that include the current position of the vehicle and forward in the traveling direction of the vehicle. And the range of the map displayed on a display apparatus is determined according to this vehicle position mark display range. Specifically, the range of the map displayed on the display device is determined as follows.
[0012]
First, the position of the vehicle position mark display range is provisionally determined so as to include the current position of the vehicle. Thereafter, an i-th guide route node (where i is a variable and the initial value is 1) in front of the current position of the vehicle and the vehicle traveling direction within the vehicle position mark display range (nodes constituting the guide route) ) Is included. When both the current position of the vehicle and the i-th guide route node are included in the vehicle position mark display range, the value of i is incremented and the next guide route node is included in the vehicle position mark display range. Check whether or not
[0013]
On the other hand, when the current position of the vehicle or the i-th guide route is not included in the vehicle position mark display range, the current position of the vehicle and the i-th guide route are changed by changing the position of the vehicle position mark display range. It is determined whether or not both can be included in the vehicle position mark display range. And when it determines with it being included, the position of a vehicle position mark display range is changed, the value of i is incremented, and said process is repeated. If it is determined that it is not included, the range of the map to be displayed on the display device is determined in accordance with the vehicle position mark display range at the present time.
[0014]
Moreover, the range of the map displayed on the display device can be determined as follows.
That is, after determining the size of the vehicle position mark display range, a calculation range based on the current position of the vehicle is determined according to the size of the vehicle position mark display range. For example, the calculation range is centered on the current position of the vehicle, and the size in the vertical and horizontal directions is twice the range of the vehicle position mark display range. Thereafter, a guidance route node that is in front of the traveling direction of the vehicle and is included in the calculation range is extracted. Then, the position of the vehicle position mark display range including the current position of the vehicle and including the largest number of extracted guide route nodes is obtained, and the range of the map displayed on the display device according to the position of the vehicle position mark display range is determined. decide.
[0015]
In this way, in the present invention, as many guidance routes as possible are displayed on the display screen, it becomes easier to confirm the state of the road ahead of the vehicle, and safety is improved.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
(First embodiment)
FIG. 1 is a block diagram showing the configuration of an in-vehicle navigation device that implements the route display method of the present invention.
[0017]
Reference numeral 1 denotes a CD-ROM storing map data. The map data stored in the CD-ROM 1 includes (1) a road layer including a road list, a node table, and an intersection configuration node list, and (2) a road, a building, a facility, a park, a river, and the like on the map screen. It consists of a background layer for displaying, (3) a character name / symbol layer for displaying characters such as administrative division names such as city names, road names, intersection names, building names, and map symbols. .
[0018]
Reference numeral 2 denotes an operation unit provided with various operation buttons and the like for operating the navigation apparatus body 10 to be described later. A GPS receiver 4 receives a GPS signal sent from a GPS satellite and detects the longitude and latitude of the current position of the vehicle. Reference numeral 5 denotes a self-contained navigation sensor, and the self-contained navigation sensor 5 includes an angle sensor 5a such as a gyro that detects a vehicle rotation angle, and a travel distance sensor 5b that generates a pulse every certain travel distance. Reference numeral 7 denotes a liquid crystal display device, and the navigation device body 10 displays a map around the current position of the vehicle on the display device 7, guide routes from the departure point to the destination, vehicle position marks, and other guidance information. Is displayed. Reference numeral 8 denotes a speaker, and the navigation apparatus body 10 transmits various kinds of guidance information to the user through the speaker 8 by voice.
[0019]
The navigation device body 10 is composed of the following. A buffer memory 11 temporarily stores map data read from the CD-ROM 1. Reference numeral 12 denotes an interface connected to the operation unit 2, 14 denotes an interface connected to the GPS receiver 4, and 15 denotes an interface connected to the self-contained navigation sensor 5. Reference numeral 16 denotes a control unit. The control unit 16 detects the current position of the vehicle based on information input from the interfaces 14 and 15, reads predetermined map data from the CD-ROM 1 into the buffer memory 11, and is read into the buffer memory 11. Various processes such as searching for a guidance route from the departure place to the destination are executed under the search conditions set using the map data.
[0020]
A map drawing unit 18 generates a map image using the map data read out to the buffer memory 11. Reference numeral 20 denotes a guidance route storage unit that stores the guidance route searched by the control unit 16, and reference numeral 21 denotes a guidance route drawing unit that draws the guidance route. In the guide route storage unit 20, all nodes of the guide route searched by the control unit 16 are recorded from the departure point to the destination. When displaying the map, the guide route drawing unit 21 reads the guide route information (node sequence) from the guide route storage unit 20 and draws the guide route with a color and line width different from those of other roads.
[0021]
Reference numeral 19 denotes an operation screen / mark generator for generating various menu screens (operation screens) and various marks such as a vehicle position mark and a cursor according to the operation status.
Reference numeral 22 denotes an audio signal generator. A plurality of voice messages are recorded in the voice signal generation unit 22 in advance, and a predetermined voice message is output to the speaker 8 in accordance with a signal from the control unit 16.
[0022]
An image composition unit 23 superimposes various marks and operation screens generated by the operation screen / mark generation unit 19 on the map image drawn by the map drawing unit 18 and the guidance route drawn by the guidance route drawing unit 21. Display on the display device 7.
In the navigation device configured as described above, the control unit 16 detects the current position of the vehicle from the GPS signal received by the GPS receiver 4 and the signal input from the self-contained navigation sensor 5. Then, map data around the vehicle is read from the CD-ROM 1 and stored in the buffer memory 11. The map drawing unit 18 generates a map image based on the map data read into the buffer memory 11 and displays a map image around the vehicle on the display device 7.
[0023]
The control unit 16 detects the current position of the vehicle based on signals input from the GPS receiver 4 and the self-contained navigation sensor 5 as the vehicle moves, and displays the map displayed on the display device 7 according to the detection result. The vehicle position mark is displayed superimposed on the image, and the vehicle position mark is moved as the vehicle moves, or the map image is scrolled.
[0024]
Further, when the user operates the operation unit 2 to set the destination, the control unit 16 sets the map data in the CD-ROM 1 as the route with the lowest cost from the current location of the vehicle to the destination. Use to explore. Then, the route obtained by the search is stored in the guidance route storage unit 20 as a guidance route, and the guidance route is superimposed on the map image and displayed. Further, the control unit 16 appropriately outputs guidance information as the vehicle travels, and guides the vehicle to travel along the guidance route to the destination.
[0025]
FIG. 2 is a flowchart showing a route display method (route wide display) according to the first embodiment of the present invention, and FIGS. 3 to 5 are schematic views showing an outline of the route display method.
In the following example, it is assumed that the search for the guidance route to the destination has been completed and the guidance route data (node data) is stored in the guidance route storage unit 20. Further, when the vehicle position mark 30 is displayed near the edge of the screen, it becomes difficult to understand the road conditions around the vehicle. Therefore, as shown in FIG. 3, when the distance A displayed in the vertical direction of the screen is 100% The vehicle position mark 30 is not displayed within a distance a1 of 15% from each end of the screen. That is, the vehicle position mark 30 is displayed within a rectangular range indicated by a broken line in FIG. This rectangular vehicle position mark display range is hereinafter referred to as a mark display range.
[0026]
In the present embodiment, first, the variable i is initialized (i = 1) in step S11. Next, the process proceeds to step S12, and the size of the mark display range is determined as described above according to the scale of the map image to be displayed. Thereafter, the process proceeds to step S13, and as shown in FIG. 3, the maximum longitude and latitude (Xmax, Ymax) and the minimum longitude (Xmin, Ymin) of the mark display range when the current position of the vehicle is centered are obtained.
[0027]
Next, the process proceeds to step S14, and the guidance route node data stored in the guidance route storage unit 20 and the map data recorded in the CD-ROM 1 are used to move forward from the current position of the vehicle in the traveling direction. The longitude and latitude Xi and Yi of the i-th node Ni (initially i = 1) of the guide route are acquired.
Thereafter, the process proceeds to step S15, and the latitudes and longitudes X0 and Y0 of the current position of the vehicle are acquired based on the signals input from the GPS receiver 4 and the self-contained navigation sensor 5.
[0028]
Next, the process proceeds to step S16, and whether or not the current position of the vehicle and the node Ni are both within the mark display range, that is, Xmin <X0 <Xmax, Ymin <Y0 <Ymax, Xmin <Xi <Xmax, Ymin <. It is determined whether Yi <Ymax. When it is determined that both the current position of the vehicle and the node Ni are within the mark display range, the process proceeds to step S17, and when it is determined that at least one of the current position of the vehicle and the node Ni is outside the mark display range. Proceeds to step S18. Initially, i = 1, and since the longitude and latitude X0 and Y0 of the current position of the vehicle and the longitude and latitude X1 and Y1 of the node N1 are both within the mark display range, the process proceeds to step S17.
[0029]
In step S17, the value of variable i is incremented. Here, i = 2 is obtained by incrementing the value of i. Thereafter, the process proceeds to step S14.
In step S14, the longitude and latitude (X2, Y2) of the node N2 is acquired. And it transfers to step S15, and after acquiring the longitude and latitude (X0, Y0) of the present position of a vehicle, it transfers to step S16. In step S16, whether the current position of the vehicle and the node N2 are within the mark display range, that is, whether Xmin <X0 <Xmax, Ymin <Y0 <Ymax, Xmin <X2 <Xmax, Ymin <Y2 <Ymax. Determine whether. Here, since both the current position of the vehicle and the node N2 are within the mark display range, the process proceeds to step S17. In step S17, the value of i is incremented to i = 3. Thereafter, the process proceeds to step S14.
[0030]
In step S14, the longitude and latitude (X3, Y3) of the node N3 is acquired. And it transfers to step S15, and after acquiring the longitude and latitude (X0, Y0) of the present position of a vehicle, it transfers to step S16. In step S16, whether or not the current position of the vehicle and the node N3 are within the mark display range, that is, whether or not Xmin <X0 <Xmax, Ymin <Y0 <Ymax, Xmin <X3 <Xmax, Ymin <Y3 <Ymax. Determine whether. Here, since both the current position of the vehicle and the node N3 are within the mark display range, the process proceeds to step S17 to increment the value of i to i = 4. Thereafter, the process proceeds to step S14.
[0031]
In step S14, the longitude and latitude (X4, Y4) of the node N4 are acquired. And it transfers to step S15, and after acquiring the longitude and latitude (X0, Y0) of the present position of a vehicle, it transfers to step S16. In step S16, whether the current position of the vehicle and the node N4 are within the mark display range, that is, whether Xmin <X0 <Xmax, Ymin <Y0 <Ymax, Xmin <X4 <Xmax, Ymin <Y4 <Ymax. Determine whether. Here, since the longitude and latitude of the node N4 is outside the mark display range, the process proceeds from step S16 to step S18.
[0032]
In step S18, it is determined whether or not the current position of the vehicle and the node (node N4 in this example) can be included in the mark display range by changing the position of the mark display range. That is, if | X0−X4 | <Xmax−Xmin and | Y0−Y4 | <Ymax−Ymin, the current position of the vehicle and the node N4 are displayed as marks by changing the position of the mark display range. Can be displayed within range. In this example, since | X0−X4 | <Xmax−Xmin and | Y0−Y4 | <Ymax−Ymin, the process proceeds from step S18 to step S19.
[0033]
In step S19, the maximum longitude and latitude of the mark display range are changed so that both the current position of the vehicle and the node are included in the mark display range. Here, as shown in FIG. 4, the maximum longitude and minimum longitude of the mark display range are changed from the mark display range indicated by the broken line A0 as indicated by the broken line A1.
Thereafter, the process proceeds to step S17, where the value of i is incremented to i = 5. In step S14, the longitude and latitude (X5, Y5) of the node N5 is acquired. Thereafter, the process proceeds to step S15 to obtain the longitude and latitude (X0, Y0) of the current position of the vehicle. Then, the process proceeds to step S16, and whether or not the current position of the vehicle and the node N5 are within the display range, that is, Xmin <X0 <Xmax, Ymin <Y0 <Ymax, Xmin <X5 <Xmax, Ymin <Y5 <Ymax. It is determined whether or not there is. Here, since it is no, it transfers to step S18 from step S16.
[0034]
In step S18, it is determined whether or not the current position of the vehicle and the node (here, node N5) can be included in the mark display range by changing the position of the mark display range. That is, if | X0−X5 | <Xmax−Xmin and | Y0−Y5 | <Ymax−Ymin, the current position of the vehicle and the node N4 are set within the display range by changing the mark display range. Can be displayed. In this example, since | Y0−Y5 | <Ymax−Ymin is not satisfied, the process proceeds from step S18 to step S20. And as shown in FIG. 5, the range which displays a map image according to the maximum longitude and minimum longitude of the present mark display range is determined.
[0035]
6 and 7 are both conventional front wide map display examples (FIGS. 6A and 7A) and map display examples according to the present embodiment (FIGS. 6B and 7B). FIG. As shown in FIGS. 6 and 7, according to the present embodiment, the mark display range is determined so that a lot of guidance routes in the traveling direction of the vehicle can be displayed, and the display according to the mark display range is displayed. Since the range of the map displayed on the device 7 is determined, there is an advantage that it is easy to confirm the state of the road ahead of the vehicle.
[0036]
(Second Embodiment)
FIG. 8 is a flowchart showing a route display method (route wide display) according to the second embodiment of the present invention. In this embodiment as well, the configuration of the vehicle-mounted navigation device is the same as that of the first embodiment, so that description will be given with reference to FIG.
First, in step S21, as in the first embodiment, the size of the mark display range is determined according to the scale of the map to be displayed (see FIG. 3).
[0037]
Next, it transfers to step S22 and determines a calculation range. As shown in FIG. 9, the calculation range is such that the horizontal distance of the mark display range indicated by the broken line is X, and the vertical distance is Y, and the vertical distance is 2X centered on the current position of the vehicle. The lateral distance is in the range of 2Y.
Next, the process proceeds to step S23, and a guide route node that is ahead of the traveling direction of the vehicle and that is included in the calculation range is extracted. Here, as shown in FIG. 9, it is assumed that nodes N1 to N6 have been extracted.
[0038]
Next, the process proceeds to step S24, and the position of the mark display range including the current position of the vehicle and including the largest number of extracted nodes is determined. For example, a process of determining one of the nodes N1 to N6 as a target node, determining a mark display range including both the current position of the vehicle and the target node, and checking the number of nodes included in the mark display range. The process is executed for each of the nodes N1 to N6, and the mark display range having the largest number of nodes is adopted.
[0039]
Next, the process proceeds to step S25, and the map display range is determined according to the mark display range.
FIG. 10A shows a conventional map display example using the front wide, and FIG. 10B shows a map display example according to the present embodiment. In the present embodiment, as shown in FIGS. 10A and 10B, even when the guide routes displayed on the screen are not continuous, the display range in which the most guide routes can be displayed can be determined. .
[0040]
Note that the processing shown in the first and second embodiments described above need not always be performed. For example, the display range may be corrected every certain time or every certain distance.
[0041]
【The invention's effect】
As described above, according to the present invention, the position of the vehicle position mark display range that includes the current position of the vehicle and that can display the most guidance routes ahead of the traveling direction of the vehicle is obtained, and the vehicle position mark Since the range of the map to be displayed on the display device is determined in accordance with the position of the display range, it is easy to check the state of the road on which the vehicle travels, and the safety is improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a vehicle-mounted navigation device that realizes a route display method of the present invention.
FIG. 2 is a flowchart illustrating a route display method according to the first embodiment of this invention.
FIG. 3 is a schematic diagram (part 1) illustrating an overview of a route display method according to the first embodiment;
FIG. 4 is a schematic diagram (part 2) illustrating an overview of a route display method according to the first embodiment;
FIG. 5 is a schematic diagram (part 3) illustrating an overview of a route display method according to the first embodiment;
6A is a diagram showing a map display example (part 1) according to a conventional method, and FIG. 6B is a diagram showing a map display example (part 1) according to the present invention.
FIG. 7A is a diagram showing a map display example (part 2) according to the conventional method, and FIG. 7B is a diagram showing a map display example (part 2) according to the present invention.
FIG. 8 is a flowchart illustrating a route display method according to the second embodiment of this invention;
FIG. 9 is a diagram illustrating a relationship between a mark display range and a calculation range.
10A is a diagram showing a map display example (part 3) according to a conventional method, and FIG. 10B is a diagram showing a map display example according to the present invention (part 3).
FIG. 11 is a diagram showing a conventional map display by front wide.
FIGS. 12A and 12B are diagrams showing examples of guidance routes and conventional problems. FIG.
[Explanation of symbols]
1 CD-ROM,
2 Operation part,
4 GPS receiver,
5 Self-contained navigation sensors,
7 Display device,
10 Navigation device body,
11 Buffer memory,
16 control unit,
18 Map drawing part,
19 Operation screen / mark generator,
20 Guide route storage unit,
21 Guide route drawing unit,
23 Image composition part,
30 Vehicle position mark.

Claims (2)

In the route display method of the in-vehicle navigation device that guides the vehicle to the destination along the guide route,
(A) Determine the size of the vehicle position mark display range,
(B) determining the position of the vehicle position mark display range so as to include the current position of the vehicle;
(C) It is determined whether or not the vehicle position mark display range includes the current position of the vehicle and the i-th (where i is a variable) guidance route node ahead of the traveling direction of the vehicle,
(D) When it is determined that it is included, the value of i is incremented and the processing from (c) is continued, and when it is determined that it is not included,
(E) Determining whether the current position of the vehicle and the i-th guidance route node are included in the vehicle position mark display range by changing the position of the vehicle position mark display range;
(F) When it is determined that it is included, the position of the vehicle position mark display range is changed, the value of i is incremented, and the processing from (c) is continued.
(G) A route display method for a vehicle-mounted navigation device, wherein a range of a map to be displayed on a display device is determined in accordance with a position of a vehicle position mark display range at the present time. In the route display method of the in-vehicle navigation device that guides the vehicle to the destination along the guide route,
(A) Determine the size of the vehicle position mark display range,
(B) determining a calculation range based on the current position of the vehicle according to the size of the vehicle position mark display range;
(C) Extract a guidance route node that is ahead of the vehicle in the traveling direction and is included in the calculation range;
(D) Finding the position of the vehicle position mark display range that includes the current position of the vehicle and that includes the largest number of extracted guide route nodes;
(E) A route display method for a vehicle-mounted navigation device, wherein a map range to be displayed on a display device is determined in accordance with a position of the vehicle position mark display range.

Images