JPH08339494A - Map display device for vehicle - Google Patents

Abstract

PURPOSE: To switch the display format of a road map according to the speed of a vehicle. CONSTITUTION: When a road map is displayed on a display device 7, a vehicle speed sensor 1 detects the vehicle speed and displays a plane map when the vehicle speed is zero and a bird's-eye map when not. While the bird's-eye map is displayed, the overlooking angle from a viewpoint is variable and made smaller and smaller as the vehicle speed becomes higher and higher. Consequently, a wide bird's-eye map can be displayed as the vehicle travels at a high speed. Therefore, when the display of the road map of the periphery of the vehicle is meaningless during a travel on a highway, etc., a wide-range road map in the direction to a destination can be displayed and a rough path to the destination can easily be grasped. When the vehicle is at a stop, the normal plane map can be displayed, so the road shape, distance relation, etc., of the periphery of the vehicle position can easily be grasped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle map display device capable of displaying a road map within a set range from a present location to a destination on a display device.

[0002]

2. Description of the Related Art When a road map is displayed on a display device, a road map is displayed in a so-called bird's-eye view display format in which the road map around the vehicle's current location is displayed in an enlarged manner compared to a distance. Is known (see, for example, Japanese Patent Laid-Open No. 2-244188). The device disclosed in the above publication places a viewpoint behind the current position of the vehicle and displays a state of looking down the traveling direction of the vehicle from this viewpoint on the screen of the display device. When such a bird's-eye view display is performed, the map information around the current location can be enlarged and displayed, and a wide range from the current location to the distant area can be displayed, so that it becomes easy to visually grasp the connection state of the road network. Also,
It is possible to display a realistic road map as if the driver himself is looking down on the road map.

[0003]

However, when a road map is displayed in a bird's-eye view, the map scale continuously changes from the lower side to the upper side of the screen, which makes it difficult to grasp the sense of distance. Therefore, it is difficult to accurately grasp the positional relationship between the roads around the intersection by stopping the vehicle at the intersection or the like.

Further, since a driver who is traveling at a high speed is often more interested in the road map in the direction of the destination than the road map around the vehicle position, it is desirable to display the road map in the widest possible range. On the other hand, since a driver who is traveling at a slow speed is often interested in intersections and the like around the vehicle position, it is desirable to display a detailed road map around the vehicle position.

It is an object of the present invention to provide a vehicle map display device capable of automatically switching the display format of a road map displayed on the display device.

[0006]

The present invention will be described with reference to FIG. 1 showing an embodiment. In the present invention, a road map storage means 3 for storing road map data relating to a road map and a current position on the road map. A road map data of a predetermined range is read out from the road map storage means 3 so that a bird's-eye view of a viewpoint placed above the surrounding sky and looking down the road map at a predetermined look-down angle and spread angle from this viewpoint is displayed on the display device 7. And bird's eye view data conversion means for converting to bird's eye view data,
A vehicle map display device comprising a display control means 4 for displaying a road map based on bird's-eye view data on a display device 7, comprising vehicle speed detection means 1 for detecting a vehicle speed, and looking down angle according to the detected vehicle speed. The above object is achieved by configuring the bird's-eye view data conversion means so as to change. The invention according to claim 2 is, in the map display device for a vehicle according to claim 1, a plane map which creates road map data by reading road map data in a predetermined range including the current location of the vehicle from the road map storage means 3. When the vehicle speed is less than the first speed, a road map based on the plane map data is provided with the data creating means and the bird's-eye view data converting means for changing the looking-down angle so that the farther distance can be seen as the vehicle speed increases. The display control means 4 is configured to display the road map based on the bird's-eye view data on the display device 7 when the vehicle speed is equal to or higher than the first speed. According to a third aspect of the present invention, in the map display device for a vehicle according to the first or second aspect, the bird's-eye view data conversion means is configured so as to keep the looking-down angle constant when the vehicle speed becomes equal to or higher than the second speed. is there. According to a fourth aspect of the present invention, a road map storage means 3 for storing road map data relating to a road map, a viewpoint is placed above the current position on the road map, and the road is viewed from this viewpoint at a predetermined look-down angle and spread angle. A bird's-eye view data conversion unit that reads road map data in a predetermined range from the road map storage unit 3 and converts it into bird's-eye view data so that the bird's-eye view looking down at the map is displayed on the display device 7, and a road map based on the bird's-eye view data is displayed. A map display device for a vehicle, comprising display control means 4 to be displayed on the device 7, comprising a setting means 5 for setting a gaze angle when displaying a bird's-eye view, and a bird's-eye view looking down on a road map at the set gaze angle. A bird's-eye view for reading road map data in a predetermined range from the road map storage means 3 so as to be displayed on the display device 7 and converting it into bird's-eye view data. It is intended to provide a chromatography data conversion means.

[0007]

According to the first aspect of the invention, the look-down angle at the time of displaying the bird's-eye view is changed according to the vehicle speed detected by the vehicle speed detecting means 1. As a result, the road map range displayed on the display device 7 changes according to the vehicle speed. In the invention according to claim 2, the vehicle speed is the first speed (for example, 20 km /
If it is less than h), a plane map is displayed on the display device 7, and if it is the first speed or more, a bird's-eye view of the road map is displayed on the display device 7. Further, when displaying the bird's-eye view, the gaze angle is changed so that a farther distance can be seen as the vehicle speed increases. As a result, a wide range road map is displayed while traveling at high speed, and a detailed map around the vehicle position is displayed while traveling at slow speed. According to the third aspect of the invention, when the vehicle speed becomes equal to or higher than the second speed (for example, 140 km / h), the overlooking angle is made constant to simplify the processing. In the invention according to claim 4, the bird's-eye view is displayed based on the preset looking-down angle. That is, the road map range displayed on the display device 7 can be changed by changing the look-down angle by setting by the operator, for example.

Incidentally, in the section of means and action for solving the above-mentioned problems for explaining the constitution of the present invention, the drawings of the embodiments are used to make the present invention easy to understand. It is not limited to.

[0009]

1 is a block diagram of an embodiment of a vehicle map display device according to the present invention. In FIG. 1, 1 is a vehicle speed sensor that detects the traveling speed of the vehicle, and 2 is a current location detection device that detects the current location of the vehicle. The current position detection device 2 detects the current position of the vehicle using a vehicle speed sensor 1, a direction sensor that detects the traveling direction of the vehicle, a GPS sensor that detects a GPS signal from a GPS (Global Positioning System) satellite, or the like. Reference numeral 3 denotes a map storage memory for storing road map data, which is composed of, for example, a CD-ROM and its reading device. The road map data stored in the map storage memory 3 mainly includes road data, name data, background data, and the like.

Reference numeral 4 is a control circuit for controlling the entire apparatus,
It consists of a microprocessor and its peripheral circuits. Reference numeral 5 is an input device for inputting a destination of the vehicle, 6 is a plane map data memory for temporarily storing road map data used when displaying a plane map of the road map viewed from directly above on the display device 7, A bird's-eye view data memory 8 temporarily stores road map data used when displaying a bird's-eye view of a road map. An image memory 9 stores image data to be displayed on the display device 7. The image data stored in the image memory 9 is appropriately read and displayed on the display device 7.

FIG. 2 is a flow chart showing the main processing of the control circuit 4, and the operation of this embodiment will be described below based on this flow chart. The control circuit 4 starts the process of FIG. 2 when the ignition key is operated to the ignition on position.

In step S1 of FIG. 2, a recommended route and a destination are set. The destination is set by the operator via the input device 5, and the recommended route is automatically set by calculation using, for example, the well-known Dijkstra method. Alternatively, a recommended route candidate is stored in advance in a ROM or the like,
Either of them may be selected as the recommended route.
Note that the recommended route may not be set if there is no particular need.

In step S2, the display screen mode is set. The display screen mode set here is, for example, 1
There are a mode for displaying only road maps of different display formats, a mode for simultaneously displaying road maps of different display formats, and the like, and the setting of these modes is performed by the operator via the input device 5.

In step S3, the display environment is set.
The display environment set here, for example, the display color of the screen,
There is a map scale etc. of the road map displayed. The operator selects the display environment via the input device 5.

In step S4, the current position of the vehicle is detected by using the current position detection device 2. In step S5, the vehicle speed sensor 1 is used to detect the traveling speed of the vehicle. In step S6, a map display process whose details are shown in FIGS.
Details of this map display processing will be described later.

In step S7, the current position of the vehicle is detected as in step S4. In step S8, it is determined whether the road map on the screen is updated, that is, whether the road map is rewritten. Here, it is determined that the road map is updated, for example, when the vehicle has traveled for a predetermined distance or more, or when the operator instructs scrolling via the input device 5.

If the determination in step S8 is affirmative, the process returns to step S5, and if the determination is negative, the process proceeds to step S9. In step S9, it is determined whether to continue the main process of FIG. For example, if a power switch (not shown) is turned off, or a switch for stopping the process is operated, the determination in step S9 is denied and the main process of FIG. 3 is ended.

If the determination in step S9 is affirmative, the process proceeds to step S10, the display of the attached information is updated, and then the process returns to step S7. Here, the attached information refers to, for example, a vehicle position mark displayed at the current position of the vehicle, and in step S10, the display position of the attached information such as the vehicle position mark is changed according to the traveling distance of the vehicle.

3 to 6 are flow charts showing details of the map display processing in step S6 of FIG. In step S101 of FIG. 3, it is determined whether the vehicle speed is zero. If zero, that is, if the vehicle is stopped, step S
In step 102, a plan view display process of FIG. 6 described later is performed to display a plan map. On the other hand, if it is determined that the vehicle speed is not zero in step S101, the process proceeds to step S103, and a process of determining the looking-down angle φ from the viewpoint when displaying the bird's-eye view according to the vehicle speed (hereinafter referred to as the looking-down angle setting process). To do. Details of the looking-down angle setting processing in step S103 will be described later. In step S104, the bird's-eye view display process of FIG. 5 described later is performed to display the bird's-eye view.

When the process of step S102 or S104 is completed, the process proceeds to step S105, and the auxiliary information such as the vehicle position mark is superposed on the display screen and the process returns.
FIG. 4 is a detailed flowchart of the looking-down angle setting process in step S103 of FIG. Step S151 of FIG.
Then, the vehicle speed V detected in step S5 of FIG. 2 is fetched. In step S152, it is determined whether the vehicle speed V is equal to or higher than a predetermined speed (for example, 140 km / h). When it is determined that the speed is equal to or higher than the predetermined speed, the process proceeds to step S153, the looking-down angle φ is set to the first angle (for example, 20 degrees with respect to the horizontal direction), and the process returns. On the other hand, if it is determined in step S152 that the speed is less than the predetermined speed, the process proceeds to step S154, the viewing angle φ is set to φ = 90−0.5 × V, and the process returns.

As described above, in the looking-down angle setting process of FIG. 4, the value of the looking-down angle φ is decreased as the vehicle speed V increases, and the looking-down angle φ is made constant when the vehicle speed V becomes equal to or higher than a predetermined speed.

FIG. 5 is a flow chart showing details of the bird's-eye view display processing of step S104 of FIG. In step S201 of FIG. 5, the display direction angle when performing the bird's-eye view display is calculated.

FIG. 7 is a diagram for explaining a method of calculating the display direction angle α. The XY axes shown in the figure indicate the road map plane, the origin O indicates the starting point of the vehicle, the coordinates G (X0, Y0) indicate the current position of the vehicle, and the coordinates P1 (X1, Y1) indicate the destination. As shown in the figure, the display direction angle α is the angle between the X-axis and the line segment (the dotted line in the figure) connecting the current position G and the destination P1 and is represented by the equation (1).

Tan α = {(Y1−Y0) / (X1−X0)} (1) In step S201, the display direction angle α is obtained based on the equation (1).

In step S202, step S in FIG.
Road map data around the current position is read from the map storage memory 3 based on the current position detected in step 4 and the display direction angle α calculated in step S201. For example, the road map data of several 10 km square including the current location is read.

In step S203, step S202
The data used when displaying the bird's-eye view is selected from the road map data read in step 3, and the selected data is stored in the bird's-eye view data memory 8. Here, in order to reduce the data amount of the road map information displayed on the display device 7, only the data whose data type satisfies a predetermined condition is extracted and stored in the bird's-eye view data memory 8. In step S204, the road map data selected in step S203 is converted into bird's-eye view data.

FIG. 8 is a diagram for explaining the conversion to bird's-eye view data. The road map is the XY plane, the viewpoint M is placed on the Z-axis orthogonal to the XY plane, and the angle of looking down from the viewpoint M is φ.
Here is an example. The rectangle abcd shown in the figure shows the display range of the display device 7 as enlargedly displayed in FIG. 9, and the trapezoid ABCD of FIG. 8 shows the road map range displayed on the display device 7.

In order to convert the road map data into the bird's-eye view data, the viewpoint M is first displayed so that all the road map data in the trapezoidal area ABCD shown in the figure can be displayed on the display device 7.
After defining the height Z, the down-looking angle φ from the viewpoint M, and the spread angle θ from the viewpoint, the bird's-eye view data projected on the rectangular area abcd in FIG. 8 is created using these parameters. At this time, the looking down angle φ is set so that the vicinity of the center line connecting the midpoints of the upper side and the lower side of the display screen of the display device 7 becomes the destination direction.

Returning to FIG. 5, in step S205, the bird's-eye view data converted in step S204 is displayed on the display device 7.
After being converted into the final map image data to be displayed on, the image data is stored in the image memory 9 and the process returns.

FIG. 6 is a flow chart showing details of the plane map display processing in step S102 of FIG. In step S301 of FIG. 6, a road map around the current position of the vehicle is read from the map storage memory 3. In step S302,
Data used for displaying a plane map is selected from the road map data read in step S301, and the selected data is stored in the plane map data memory 6 as the plane map data. Note that in step S302, similarly to step S203 in FIG. 5, data or the like having a high priority is selected. In step S303, the plane map data stored in the plane map data memory 6 is converted into map image data and then stored in the image memory 9,
To return.

As described above, in the present embodiment, the vehicle speed is detected when the road map is displayed on the display device 7, the plane map is displayed when the vehicle speed is zero, and when the vehicle speed is not zero. Displays a bird's eye view. Further, when the bird's-eye view is displayed, the view-down angle φ from the view point can be changed, and the view-down angle φ is reduced as the vehicle speed increases. Therefore, a wider bird's-eye view can be displayed when traveling at a higher speed.

FIG. 10 (a) is a road map displayed on the display device while traveling at high speed, FIG. 10 (b) is a road map displayed while traveling at slow speed, and FIG. 10 (c) is stopped. Each of the road maps displayed inside is shown. As shown in the figure, a plane map in which the gaze angle φ is set to 90 degrees is displayed during the stop, and the gaze angle φ is reduced so that the gaze angle can be viewed further as the vehicle speed increases.

As described above, according to the present embodiment, when it is not so meaningful to display the road map around the vehicle position, such as when driving on an expressway, a wide range road map in the direction of the destination is displayed. Is displayed, it is easy to understand the rough route to the destination. On the other hand, when the vehicle is stopped, a normal plane map is displayed, which makes it easier to understand the road shape and distance relationship around the vehicle position. Further, according to this embodiment, even if the driver or the like does not switch the display mode by operating the switch, the display mode is automatically switched according to the vehicle speed, so that the usability is improved.

In the above embodiment, an example of changing the look-down angle φ according to the vehicle speed has been described. However, the look-down angle φ and the spread angle θ and the height M of the viewpoint may be changed. Further, in the above-described embodiment, an example in which the looking-down angle φ is changed based on the formula of φ = 90−0.5 × V has been described, but the formula for changing the looking-down angle φ is not limited to the above formula. Furthermore, the angle of looking down is linearly changed according to the vehicle speed.
May be changed stepwise instead of changing. Further, in the above embodiment, the plane map is displayed only when the vehicle speed is zero, but the vehicle speed is a predetermined speed (for example, 20 k).
A plan map may be displayed in the case of m / h) or less.

In the map display process of FIG. 3, an example of changing the looking-down angle φ from the viewpoint according to the vehicle speed has been described.
The looking-down angle φ may be changed according to an instruction from the operator. FIG. 11 is a detailed flowchart of a modified example of the map display process. In step S401 of FIG. 11, it is determined whether or not the looking-down angle φ set by the operator using the input device 5 is 90 degrees. When 90 degrees is set as the looking-down angle φ, the process proceeds to step S402 and the plan map display process of FIG. 6 is performed to display the plan map. On the other hand, when the looking-down angle φ is other than 90 degrees, the process proceeds to step S403, and the bird's-eye view display process of FIG. 5 is performed based on the looking-down angle φ set by the operator to display the bird's-eye view. When the process of step S402 or S403 is completed, the process proceeds to step S404, the attached information is displayed, and the process returns.

In the above embodiment, the map storage memory 33 is the road map storage means, the control circuit 4 is the display control means, the vehicle speed sensor 1 is the vehicle speed detection means, and the bird's-eye view display processing of FIG. 5 is the bird's-eye view data conversion means. The planar map display processing of FIG. 6 corresponds to the planar map data creating means, and the input device 5 corresponds to the setting means.

[0036]

As described above in detail, according to the present invention, the view angle when the bird's-eye view is displayed is changed according to the vehicle speed, so that the road map in the range suitable for the driving situation can be displayed in the bird's-eye view. . Moreover, since the road map range is automatically changed without providing a dedicated operation member, usability is improved. According to the second aspect of the present invention, when the vehicle speed is lower than the first speed, a plane map looking down on the road map from above is displayed, so that the road condition around the vehicle position can be easily grasped. Also, when displaying a bird's-eye view, as the vehicle speed increases, the gaze angle is changed so that you can look farther away.For example, if you are traveling at high speed, you can display a wide range toward the destination, It becomes easier to understand the general route. On the other hand, when the vehicle is traveling at a slow speed, the road map around the vehicle position can be displayed in detail, and the road condition around the vehicle position can be easily grasped. According to the invention as set forth in claim 3, since the looking-down angle is made constant when the vehicle speed becomes equal to or higher than a predetermined speed, the processing can be simplified. According to the invention as set forth in claim 4, since it is possible to change the setting of the look-down angle at the time of displaying the bird's-eye view, the road map displayed in the bird's-eye view can be arbitrarily changed according to the instruction of the operator.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a vehicle map display device according to the present invention.

FIG. 2 is a flowchart showing main processing of a control circuit.

FIG. 3 is a detailed flowchart of the map display process of step S6 of FIG.

4 is a detailed flowchart of a view angle setting process in step S103 of FIG.

5 is a detailed flowchart of the bird's-eye view display process in step S104 of FIG.

6 is a detailed flowchart of the planar map display process of step S102 of FIG.

FIG. 7 is a diagram illustrating a method of calculating a display direction angle α.

FIG. 8 is a diagram illustrating conversion into bird's-eye view data.

9 is an enlarged view of the rectangular area abcd in FIG.

FIG. 10 is a diagram showing an example of a road map in which the looking down angle is changed according to the vehicle speed.

FIG. 11 is a detailed flowchart showing a modified example of map display processing.

[Explanation of symbols]

 1 Vehicle speed sensor 2 Current location detection device 3 Map storage memory 4 Control circuit 5 Input device 6 Plane map data memory 7 Display device 8 Bird's eye view data memory 9 Image memory

Claims (4)

[Claims] 1. A road map storage means for storing road map data relating to a road map, and a viewpoint is placed above the current location on the road map, and the road map is looked down at a predetermined looking-down angle and spread angle from this viewpoint. A bird's-eye view data conversion unit that reads the road map data in a predetermined range from the road map storage unit and converts the road map data into bird's-eye view data so that the bird's-eye view data is displayed on the display device, and a road map based on the bird's-eye view data display device. A map display device for a vehicle, comprising: display control means for displaying the vehicle speed; and a vehicle speed detection means for detecting a vehicle speed, wherein the bird's-eye view data conversion means changes the look-down angle according to the detected vehicle speed. A map display device for a vehicle characterized by: 2. The vehicle map display device according to claim 1, wherein the road map storage unit reads out the road map data in a predetermined range including the current location of the vehicle from the road map storage unit and creates plane map data. The bird's-eye view data conversion means changes the look-down angle so that a farther view can be seen as the vehicle speed increases, and the display control means is based on the plane map data when the vehicle speed is less than a first speed. A map display device for a vehicle, which displays a road map on the display device, and displays a road map based on the bird's-eye view data on the display device when the vehicle speed is equal to or higher than the first speed. 3. The vehicle map display device according to claim 1, wherein the bird's-eye view data conversion unit keeps the looking-down angle constant when the vehicle speed is equal to or higher than a second speed. Map display device. 4. A road map storage means for storing road map data relating to a road map, a viewpoint is placed above the current location on the road map, and the road map is looked down at a predetermined looking-down angle and spread angle from this viewpoint. A bird's-eye view data conversion unit that reads the road map data in a predetermined range from the road map storage unit and converts the road map data into bird's-eye view data so that the bird's-eye view is displayed on the display device, and a road map based on the bird's-eye view data is displayed on the display device. A map display device for a vehicle, comprising: display control means for displaying on the road; and a setting means for setting the look-down angle at the time of bird's-eye view display, the bird's-eye view data conversion means, the road at the set look-down angle. In order that a bird's-eye view looking down on the map is displayed on the display device, the road within a predetermined range from the road map storage means. Vehicle map display apparatus characterized by converting the bird's-eye view data reads map data.