JP3152051B2 - Navigation system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation system and, more particularly, to a map display type navigation system.

[0002]

2. Description of the Related Art Conventionally, in a vehicle navigation system of a map display type, the center of the map display is often set as the position of the vehicle, and the mark of the vehicle is always displayed at the center of the screen. The map scrolls. Further, the scale of the map is manually selected and set by a driver operating a panel switch or the like. In many cases, the selected scale is not changed until the driver operates the panel switch again or a situation occurs in which a map stored in a CD-ROM or the like does not have a map of a desired scale. Was adopted. (For example, JP-A-1-202615)

[0003]

In the conventional display method,
The displayed map range is the same range in front of and behind the vehicle, and the display range remains at the selected scale regardless of whether the traveling speed of the vehicle is high or low. However, while the vehicle is traveling, the driver often needs the map information of the traveling direction, and the higher the traveling speed, the wider the range becomes, so that it is difficult to obtain sufficient information.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to improve the inconvenience of the prior art, and in particular, to display appropriate information according to the running state of a vehicle, thereby improving the convenience and operability of use. The aim is to provide a navigation system that can.

[0005]

SUMMARY OF THE INVENTION The present invention provides a map data storage unit for storing map data such as road information, a position detection unit for detecting a current position of a vehicle, and a vehicle speed detection unit for detecting a current vehicle speed. A navigation system comprising: a traveling direction detecting unit that detects a traveling direction of the vehicle; and a system control unit that combines the own vehicle traveling position detected by the position detecting unit with the map data and outputs the combined data to a display unit.

In this navigation system, the system control unit changes the scale of the map data to be output to the display unit in accordance with the vehicle speed detected by the vehicle speed detection unit, and the traveling scale calculated by the traveling direction detection unit. A display center setting means for setting a position separated by a distance L in the direction as a display center position of the map data is provided.

[0007] With this, the above-mentioned object is achieved.
Is what you do.

In this navigation system, the system control section displays a position separated by a distance L in the traveling direction calculated by the traveling direction detection section according to the vehicle speed detected by the vehicle speed detection section as a display center position of the map data. A configuration including a center setting means is adopted. This aims to achieve the above-mentioned object.

Here, the distance L refers to the distance from the center point of the display unit to the display position of the own vehicle.

[0010] By means of these problem solving means, it is intended to achieve the above-mentioned common object of displaying appropriate information in accordance with the running state of the vehicle, in particular, appropriately changing the display area in accordance with the running speed. Is what you do.

[0011]

According to the navigation system of the present invention , during operation, the position detecting section detects the position of the vehicle based on outputs from various sensors.
The current position of the vehicle is constantly detected. In response to this, the system control unit, the vehicle traveling position detected by the position detection unit,
The map data is combined with map data such as road information acquired from the map data storage unit and output to the display unit.

At this time, first, the display scale switching means of the system control unit changes the scale of the map data to be output to the display unit according to the vehicle speed detected by the vehicle speed detection unit. When the vehicle speed increases, map data with a small scale and a large display area is called, and when the vehicle speed decreases, map data with a large scale and a small display area is called. Since the width of the switching speed is set corresponding to the number of map data for each scale, for example, if the map data storage unit has map data for each of the eight scales, the map data of the eight scales is used. A speed area is set in advance, and the display scale is switched when the speed area changes.

[0013] Next, the display center setting means displays, on the display, a point on the display at a point separated from the current position of the own vehicle by the distance L in the traveling direction based on the traveling direction of the vehicle detected by the traveling direction detecting section. Point.

Further, the system control unit calls the map data switched by the display scale switching unit based on the center point set by the display center setting unit, combines the map data with the own vehicle position, and outputs it to the display unit.

Further, in the present navigation system, during the operation of the navigation system, the own vehicle display maintaining function of the display center setting means changes the distance L in accordance with the vehicle speed on a reduced scale map set by the driver.

When the vehicle speed increases, the distance L must be increased.
Conversely, if the speed is low, take a short time.

Next, the distance L calculated according to the vehicle speed
However, for example, half of the largest circumference that can be drawn on the screen
When the distance exceeds the distance L1 such as the diameter, the scale of the map data is reduced.
change.

[0018]

Next, an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, the display center is set to a distance away from the own vehicle position by a distance corresponding to the traveling speed in the traveling direction of the vehicle, and the traveling vehicle is thereby increased in speed and deviated from the display map. In such a case, the display scale is automatically reduced by one step from the current display map scale, and conversely, when the speed is reduced, the display map is automatically raised by one step to the first display map scale. This is a navigation system.

FIG. 1 is a functional block diagram for explaining the conceptual configuration of the present embodiment. The navigation system is
Map data storage unit 2 storing map data such as road information
A position detector 4 for detecting the current position of the vehicle, a vehicle speed detector 8 for detecting the current vehicle speed, a traveling direction detector 6 for detecting the traveling direction of the vehicle, The system control unit 10 combines the vehicle travel position and the map data and outputs the combined data to the display unit 16.

Further, the system control unit 10 changes the scale of the map data to be displayed according to the vehicle speed detected by the vehicle speed detection unit 8, and the display scale switching unit 12. Display center setting means 14 for setting a position separated by a distance L as a display center position of map data
It has.

The display scale switching means 12 of the system control unit 10 has a vehicle display maintaining function of changing the distance L according to the vehicle speed and changing the scale of the map data when the distance exceeds a predetermined distance L1. ing.

FIG. 2 is a block diagram showing a hardware configuration of this embodiment, and FIG. 3 is a perspective view showing an example of installation in a vehicle. The navigation system includes a display / operation unit 20, a map data storage unit 24, and a group of sensors 26 for detecting a position, a traveling speed, and a traveling direction of the vehicle, with a system control unit 22 at the center.

This will be described in detail. The display unit 16 is controlled by the system control unit 10, receives image data from the map data storage unit 2, and displays the image data. The display unit 16 here uses a liquid crystal display (LCD), and displays an image by applying a voltage to a liquid crystal material sealed between two glasses. The display unit 16 first displays the road image data transmitted by the system control unit 10 in the R
It is stored in each image memory for each GB. Next, a voltage according to the gradation of the stored image data is output to the LCD.
The glass on the display side is provided with filters for each color of RGB, and the display unit 16 displays color image data by applying a voltage based on the image data for each position of the filter.

When displaying the road data, north is usually displayed at the top of the screen, but when the traveling direction of the own vehicle is at the top of the screen, the process of receiving the road data from the map data storage unit 2 and storing it in the image memory. The image information is rotated during the process of outputting the voltage to the LCD. The system control unit 10 is, for example, when the vehicle is traveling south, by performing <br/> mark pressurizing the voltage After rotating the coordinates for displaying the image data 180 degrees, rotates the display image Let me.

The display unit 16 may be configured using a cathode ray tube or a projector instead of an LCD, because a large display may be suitable for a rear seat, a passenger of a large vehicle, or the like.

An input unit 18 is provided near the display unit 16. The input unit 18 receives a driver's key operation. The received settings and the like are transmitted to the system control unit 10, and the system control unit 10 sets the destination and switches the map scale received from the driver. The display / operation unit 20 includes the display unit 16 and the input unit 18.

Here, the map data storage unit 2 stores a CD-
ROM is adopted. The CD-ROM is an optical disk and is mainly used as a read-only memory. The capacity is usually about 550 Mbytes, which is used for music reproduction and as a storage medium for text and image data. Here, the CD-ROM stores road map data of a plurality of scales, place names, and data indicating the relationship between each place name and a position on the road map. Further, information on a golf course, a repair shop, and the like may be stored. The map data storage unit 8 may be any nonvolatile storage medium having a large storage capacity other than the CD-ROM as long as it can be installed in the vehicle. For example, a magneto-optical disk or a memory card is used. Further, the map data may be transmitted from outside the vehicle.

In this embodiment, the map data unit 24
Includes a map data storage unit 2 and a driving unit for driving the map data storage unit 2. For example, if the storage unit 2 is a CD-ROM, the driving means is a CD-ROM drive. The map data unit 24 includes a plurality of CD-Rs.
It has an OM drive. A drive in which a CD-ROM required by the navigation system is always installed, and a drive in which a music CD player is shared and a CD-ROM storing special road information and the like can be used.

The vehicle speed detector 8 has a wheel speed sensor, and there are various types of wheel speed sensors such as a magnetic type, an electric type, and a mechanical type. Here, the rotation proportional to the rotation of the front wheel is taken out, and this rotational force is replaced with speed. The vehicle speed is converted into a digital quantity by the vehicle speed detection unit 8 as needed.

The traveling direction detector 6 detects the direction of the vehicle. The method is a geomagnetic sensor, the difference between the left and right wheel speeds,
There are various types such as a gyroscope. Here, a geomagnetic sensor and a rate gyroscope are employed. The geomagnetic sensor is attached substantially at the center of the roof, and determines the current direction of the vehicle by detecting geomagnetism. The geomagnetic sensor includes an AC power supply, an annular coil, an X-direction detection coil, and a Y-direction detection coil. When an AC magnetic field is applied to the annular core, an equal induced voltage is generated in the two detection coils that intersect vertically due to a change in the magnetic field from the annular coil. Occurs. By replacing the difference between the induced voltages with the bearing, the geomagnetic sensor outputs the bearing of the vehicle. Further, here, the turning angular velocity output by the rate gyro is integrated, and the azimuth of the own vehicle is corrected based on the integrated value.

The position detecting section 4 detects the position of the host vehicle based on signals from the sensors 5. In the present embodiment, a hybrid navigation system is used in which the current position of the vehicle is recognized using a geomagnetic sensor or a rate gyro and a wheel speed sensor, and the position of the vehicle is corrected when a GPS signal is properly received. The position detector 4 detects the traveling distance of the own vehicle from the rotation of the wheels and the circumference of the tire of the own vehicle. Further, a traveling route from the defined position is calculated from the azimuth and the traveling distance of the vehicle, and this is output as the current position of the own vehicle. When the vehicle is traveling in an area where GPS signals can be received well, the current position detected from the azimuth and travel distance of the vehicle is compared with the current position calculated from three or four GPS signals. Is corrected.

The position detector 4 may employ various sensors other than the above-described configuration as long as the configuration detects the traveling position of the vehicle. For example, a configuration may be used in which the position of the vehicle is detected from a road traffic information beacon or the like using a facility such as a sign post.

The position detecting section 4 functions as described above by the sensors 26 and the system control unit 22.

Next, various data processing in the system control unit 22 will be described with reference to FIGS.
The system control unit 22 is electrically, optically, magnetically, or mechanically connected to the various sensors 26 and receives outputs from the various sensors 26. The system control unit 22 includes various sensors 26, a map data storage unit 24, a connector to the display / operation unit 20, a power supply unit, and the system control unit 10.

As shown in FIG. 7, the system control section 10 executes various processes periodically and according to conditions.
Here, an example of processing for changing the scale selected by the driver to the display scale of the map according to the change in vehicle speed will be described.
The sensor signal from each sensor group 26 is taken into the system control unit 22 at regular intervals, and the position detection unit 4 and the system control unit 10 determine the traveling speed v, the traveling distance Lg,
The traveling direction d and the current position P (x, y) are calculated. Here, the x- and y-coordinates of the current position P (x, y) are the current position P of the vehicle read from the map data storage unit 24.
It is a coordinate value on the map data including (x, y).

When the current position of the vehicle is calculated, the map data and the current position are displayed on the display unit 16 at regular intervals, for example, at one second intervals. At this time, the display center setting means 14 sets the center of the display screen at a position Q separated from the current position of the vehicle by a distance L corresponding to the traveling speed in the traveling direction of the vehicle.
(X, y). (FIG. 4). The relationship between Q (x, y) and P (x, y) is, for example, as shown in the following equation 1.

[0037]

(Equation 1)

Here, L = f (υ) = υ · α

Where υ is the running speed and α is a constant. d is the traveling direction, which is 360 degrees with the x-axis direction being 0 degree.
Degrees.

The scale of the displayed map is basically the scale selected by the driver's operation. However, when the traveling speed of the vehicle increases and the current position of the vehicle is more than a predetermined distance L1 from the display center, the vehicle may deviate from the screen, and the scale is automatically reduced by one step and displayed ( (Fig. 5). The constant distance L1 is set, for example, as in Expression 2 according to the scale of the display map.

[0041]

## EQU2 ## L1 = β.γ... Equation 2.

Where γ is the radius on the map of the largest circle that can be displayed on the display screen at the current scale, and β
Is a coefficient of 1 or less and less than 0.

For this reason, the system control unit can reduce the display to the minimum scale and display it in response to the increase in the vehicle speed. Also, by the processing shown in FIGS. 8 and 9,
When the display speed is lower than the scale 1 selected by the driver and the running speed of the vehicle decreases and the current position of the vehicle is less than a predetermined distance L2 from the display center, the scale is automatically increased by one level. It is displayed (FIG. 6). here,
The relationship between the driver's selected scale and the current display scale level is held as a state number (steps S4 to S8), and the distance L is compared with L1 and L2 for each state number (step S9). To S16), the display scale adjustment variable R is obtained, and the display scale is changed according to the value of R (step S17).

The adjustment variable R of the display scale level is compared with L1 at a fixed distance L2 which is increased by one step, and L1> L2.
In response to the decrease in the vehicle speed, it can be displayed up to the scale 1 selected by the driver. However, if there is no map data of the scale 1 selected by the driver in the map data storage unit depending on the traveling position of the vehicle, the display is performed up to the maximum scale of the storage unit at the traveling position.

Further, an example of processing when the display scale and the distance L are changed only by the traveling speed regardless of the setting from the driver will be described with reference to FIG. FIG. 10 is a chart showing the relationship between the speed area and the display scale. In this case, the map data storage unit stores data from 1 / 500,000 to 1 / 25,000.
Up to four scale maps are stored. By enlarging and displaying the scale map of 1 / 25,000, the system control unit 10 displays map data of five scales. In addition, the map data of the detailed map such as 1/25000 is
Only available for urban areas with more than 100,000 people.

When the vehicle is traveling in an urban area, the display switching means 12 switches the scale according to the five-speed areas corresponding to the five-step map data for the urban area. This speed area is determined according to the map data. For example, when traveling in an urban area while traveling on a highway, a detailed map is often unnecessary, and a wide area map is displayed. In addition, when traveling in an area other than an urban area, the speed area is changed to three levels in order to display map data on a three-step scale.

The display center setting means 14 changes the value of the distance L. When traveling in an urban area, since the map scale is given corresponding to the five speed areas, a function for the speed is determined so as to move between L1 and L2 in each speed area. ing. This automatic scale change functions when the driver instructs the automatic scale mode from the input unit. Therefore, when the driver particularly wants to change the scale of the map data, for example, when displaying a wide-area map while the vehicle is stopped, the mode for changing the display scale based on the driver setting described above is selected.

When character data and road width information are separately stored and can be displayed at any scale, the scale is changed according to the traveling speed, and the value of the distance L is changed at the same time. May be configured. For example, the distance L may be changed in the case of acceleration and deceleration, and the scale may be changed when the vehicle is traveling at a constant speed for a certain period or more. In addition, the scale may be changed in three stages according to the change in the vehicle speed.

As described above, according to the first embodiment, the map information of the traveling direction of the vehicle is given to the driver according to the traveling speed, so that the change of the traveling direction and the selection of the road can be performed quickly. become.

Next, a reference example will be described. FIG. 11 is a functional block diagram showing the configuration of the navigation system according to the reference example. The navigation system includes a map data storage unit 30 storing map data such as road information, a position detection unit 32 for detecting a current position of the vehicle, a vehicle speed detection unit 36 for detecting a current vehicle speed, and a traveling direction of the vehicle. And a system control unit 38 that combines the own vehicle traveling position detected by the position detection unit 32 with the map data and outputs the combined data to the display unit 44.

Further, the system control unit 32 displays a position separated by a distance L in the traveling direction calculated by the traveling direction detection unit 34 according to the vehicle speed detected by the vehicle speed detection unit 36 as a display center position of the map data. A center setting means 40 is provided.

[0052] explaining the operation of the navigation system of the present embodiment. The position detection unit 32 always detects the current position of the vehicle based on outputs from various sensors. In response to this, the system control unit 38 combines the own vehicle traveling position detected by the position detection unit 32 with map data such as road information acquired from the map data storage unit 30 and outputs the combined data to the display unit 44.

At this time, the system control unit 38 uses the display center setting means 40 to set a position separated by a distance L corresponding to the vehicle speed in the traveling direction of the vehicle as the display center position of the map data. When the vehicle runs at a high speed, the distance L increases, and as the speed decreases, the distance L decreases. Based on the display center position that changes in this way, the system control unit 40 calls up the map data from the map data storage unit 30, combines it with the own vehicle position, and outputs it to the display unit.

As described above, according to this reference example, as the traveling speed increases, the distance L increases, and the map data in the traveling direction is displayed wider. Conversely, as the traveling speed decreases, Since the surrounding map data is displayed regardless of the traveling direction, it is possible to present information useful for changing the direction of the vehicle.

[0055]

Since the present invention exhibits functions constructed as described above, according to this, in the navigation system,
The display control unit of the system control unit changes the scale of the map data to be output to the display unit according to the vehicle speed detected by the vehicle speed detection unit. Map data can be displayed. Further, for example, if the map data storage unit has map data for each of the eight scales, this switching is performed when the display scale is changed from a certain area to another area in the eight-speed range. A switching operation can be performed. Further, the display center setting means sets a point separated from the current position of the own vehicle by the distance L in the traveling direction based on the traveling direction of the vehicle as a center point to be displayed on the display.
The system control unit can always display the map data in the traveling direction required by the driver widely. In this way, it is possible to display appropriate information according to the traveling state of the vehicle, and the convenience and operability of use are dramatically improved.
It is possible to provide an excellent navigation system that has never existed before.

Further, in the present navigation system, the display center setting means increases the distance L when the vehicle speed increases, and shortens the distance L when the vehicle speed decreases. For this reason, the system control unit can display distant map information as the vehicle speed increases, and widely displays the map information near the own vehicle as the vehicle speed decreases, and also widely displays the map information of the direction change destination. can do. Further, even if the processing is started from the scale set by the driver, the scale of the map data is changed by the own vehicle display maintaining function when the distance L calculated according to the vehicle speed exceeds a predetermined distance L1. Therefore, it is possible to eliminate the possibility that the display of the own vehicle position may not be displayed on the display based on the calculation method of the distance L and the number of display pixels on the display. As described above, by changing the display position of the own vehicle on the display according to the vehicle speed, it is possible to display appropriate information according to the running state of the vehicle, and the convenience and operability of use are dramatically improved. It is possible to provide an improved navigation system that has never been improved.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a hardware configuration according to an embodiment;

FIG. 3 is a perspective view showing an example of installation in a vehicle according to the embodiment.

FIG. 4 is an explanatory diagram showing an example of a distance L.

FIG. 5 is an explanatory diagram illustrating an example of a predetermined distance L1.

FIG. 6 is an explanatory diagram showing an example of a change in display scale.

FIG. 7 is a flowchart showing a process of processing a sensor signal.

FIG. 8 is a flowchart showing processing steps for selecting a display scale.

FIG. 9 is an explanatory diagram showing processing steps for correcting a display scale by distances L1 and L2.

FIG. 10 is a table showing a relationship between a speed range and a scale.

FIG. 11 is a functional block diagram illustrating a configuration of a reference example.

[Explanation of symbols]

 2 map data storage unit 4 position detection unit 6 traveling direction detection unit 8 vehicle speed detection unit 10 system control unit 12 display scale switching unit 14 display center setting unit 16 display unit 18 input unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G01C 21/00 G08G 1/0969 G09B 29/10

Claims (1)

(57) [Claims] 1. A map data storage unit that stores map data such as road information, a position detection unit that detects a current position of a vehicle, a vehicle speed detection unit that detects a current vehicle speed, and detects a traveling direction of a vehicle. And a system control unit that combines the own vehicle traveling position detected by the position detection unit with the map data and outputs the map data to a display unit. Display scale switching means for changing the scale of the map data to be output to the display unit in accordance with the vehicle speed detected by the detection unit; Display center setting means for setting a display center position, wherein the display scale switching means of the system control unit is adapted to respond to vehicle speed.
To change the distance L and exceed the predetermined distance L1
Occasional vehicle display maintenance machine that changes the scale of the map data
A navigation system characterized by having functions .