JP3471128B2 - Car 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 vehicle-mounted navigation device, and more particularly to a vehicle-mounted navigation device with reduced power consumption.

[0002]

2. Description of the Related Art A vehicle-mounted navigation device reads out map data corresponding to the current position of an automobile from a map data storage unit such as a CD-ROM, draws a map on the display screen based on the map data, and displays the position of the automobile. The mark (location cursor) is fixedly displayed at a fixed position on the display screen (for example, the center position of the display screen), and the map is scrolled according to the movement of the automobile.

For turning on / off the power supply in such a conventional vehicle-mounted navigation device, after turning on the Acc switch of the vehicle or turning on the Acc switch,
The operation is started by a simple key operation, and the operation is stopped by turning off the Acc switch. Alternatively, the screen display may be turned off by a key operation.

[0004]

While the power is on,
The current device configuration consumes a current of several amperes, and this value cannot be said to be sufficiently small, and the power consumption of the navigation device side has been reduced due to the recent energy conservation tendency of the car itself and cost reduction. Is considered to be essential. An object of the present invention is to provide a vehicle-mounted navigation device that can save electric power.

[0005]

According to the present invention, there is provided a map storage medium storing map data, a vehicle position detecting means for detecting a current position of a vehicle, and guidance to a desired destination. A guide route storage unit that stores a route, a current position of the vehicle detected by the vehicle position detection unit, road data corresponding to the current position read from the map storage medium, and a guide read from the guide route storage unit. A map image drawing unit that draws a map image based on a route, a video RAM that stores the map image drawn by the map image drawing unit, and image data output by the video RAM that is converted into a predetermined video signal. An image conversion unit, a display device that displays an image output from the image conversion unit, the map image drawing unit, the video RAM, the image conversion unit, and the display. A) Power source control means for controlling the power supply to the device, and when the guide route ahead of the current position of the vehicle detected by the vehicle position detection means is required to run along the road, the power source control means performs the map image. Even when the power supply to the drawing unit, the video RAM, the image conversion unit, and the display device is cut off, and then when it is detected that the vehicle approaches a point requiring guidance, it is also detected that the traveling route deviates from the guidance route . Also in this case , the map image drawing unit and the video RA are controlled by the power supply control means.
M, the video conversion unit, and a guide unit for starting power supply to the display device.

Further, according to the present invention, the above-mentioned problems are stored in a map storage medium storing map data, a vehicle position detecting means for detecting the current position of the vehicle, and a guide route to a desired destination. Guide route storage means and the vehicle position detection hand
The current position of the vehicle detected by the step and the map storage medium
Road data corresponding to the current position read from
Based on the guide route read from the guide route storage means
A map image drawing unit for drawing a map image and the map image drawing unit.
A video RAM for storing the map image drawn by the image section,
The image data output from the video RAM is transferred to a predetermined video signal.
Video conversion unit for converting into a video signal and output from the video conversion unit
A display device for displaying an image, a voice synthesizing unit for generating a guide voice signal, an amplifier for amplifying the guide voice signal generated by the guide voice synthesizing unit, the map image drawing unit,
The video RAM, the image conversion unit, the display
In the case where the device, the voice synthesizer, and a power supply control unit that controls the power supply to the amplifier, and the guide route ahead of the current position of the vehicle detected by the own vehicle position detection unit can be driven along the road, wherein the said power supply control means
A map image drawing unit, the video RAM, the video conversion unit,
Said display device, the voice synthesis unit, and cut off the power supply to the amplifier, then, even if it detects that it has approached the point that requires induction, even when detecting that the travel route from the navigation route is out, the The map image drawing unit, the video RAM, and the screen are controlled by a power supply control unit.
This can be solved by providing an image conversion unit, the display device, the voice synthesis unit, and a guide unit that starts power supply to the amplifier.

[0007]

The power supply control unit turns on / off the power supply of the unit concerning the screen display and the synthetic voice output. The guide unit displays a screen on the power supply control unit when it is determined that the vehicle position detected by the vehicle position detection means is a simple part of the guide route, that is, a part that does not require guidance, and a composite display is displayed. Turn off the power supply to the unit for audio output. Vehicle position detection and map matching continue.

After that, when the guide section detects that the destination, the intersection or the like is approaching or that the traveling path has deviated from the taxiway, it determines that guidance is necessary, and the power source control section displays the screen and outputs a unit related to synthesized voice output. Turn on the power supply of to restore the operation. Therefore, the power can be saved without any trouble in the induction.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of a vehicle-mounted navigation device according to the present invention, in which 1 is a CD constituting a road map.
A map storage medium such as a ROM. Map data is (1)
It is composed of a road layer, (2) a background layer for displaying objects on a map, (3) a character layer for displaying names of cities, towns and villages, and the like.

The map stored in the map storage medium 1 is divided into regions of a longitude width and a latitude width of appropriate sizes according to the scale level, and a road has a vertex represented by coordinates of longitude and latitude ( Node). A part that connects two or more nodes is called a link. The road data included in each map is road link data RLDT and node data N.
It is composed of DDT and intersection data CRDT. Among them, the road link data RLDT gives the attribute information of the road link. The number of all nodes on the link and the number on the node data NDDT of each node forming the link. , Road name, road type, and the like. Further, the intersection data CRDT is a set of numbers on the node data NDDT of a node (referred to as each intersection node) closest to the intersection on the link connecting the intersections on the map, and the node data NDDT is the map. It is a list of all the above nodes, and coordinate information (longitude,
Latitude), an intersection identification flag indicating whether or not the node is an intersection, a pointer pointing to the intersection if the node is an intersection, and a road link to which the node belongs if the node is not the node.

A CRT display device 2 inputs a video signal and displays a map on a screen together with a vehicle position mark, an intersection guidance image and the like. Reference numeral 3 is a vehicle position detecting means for calculating the current position based on the traveling distance and direction of the moving vehicle, and a GPS receiver and a direction sensor (geomagnetic sensor, optical gyro, vibration gyro, etc.) for detecting the traveling direction of the vehicle. And a vehicle speed sensor (speed pulse detection, etc.) that detects the traveling distance.

4 is a map search key, a map scroll key,
An operation unit 5 including a route search mode key, a set key, a search start key, etc. is a navigation controller,
It generates a map image (background, characters) around the current location and also generates a car position mark and the like.

In the navigation controller 5,
Reference numeral 5A is a buffer memory for temporarily storing the map data read from the map storage medium 1, and 5B is a map drawing unit, which is based on the current position of the vehicle and around the current position, and
Data wider than the screen display range (for example, map data for 9 screens) is read from the map storage medium 1 to the buffer memory 5A, and a map image is drawn in the video RAM 5C described later. The video RAM 5C stores the map image drawn by the map drawing section 5B.

The CPU 5D calculates the current position (longitude, latitude) of the vehicle by the vehicle position detecting means 3 and synthesizes the vehicle position on the map around the current position read from the map storage medium 1 to the buffer memory 5A. The map matching unit 5E is a guide unit, and when an approach of a vehicle to an intersection (for example, approaching within 100 meters) is detected, the map matching unit 5E is provided in a V-RAM (not shown) based on the intersection node of the buffer memory 5A. Also, the enlarged shape image of the intersection is read from the intersection information storage means (not shown) and drawn.

The guide unit 5E reads the enlarged shape image of the intersection from the intersection information storage means and displays it, and also obtains the node number of the other end node of the link forming the intersection of the obtained node. Reference numeral 5I is a video conversion unit that converts the image data output from the video RAM 5C into a predetermined video signal and outputs the video signal to the CRT display device 2.

Reference numeral 5J is a voice synthesizing unit, which generates various types of guidance output from the guide unit 5E, for example, the name of the city where the intersection turns right or left and the like by a voice signal. 5K is a D / A converter for converting the audio signal which is digital data into analog, 5L is an amplifier for amplifying the audio signal input to the D / A converter 5K, 6 is an audio conversion of the audio signal after being amplified by the amplifier 5L Speaker.

Reference numeral 5N designates a destination setting portion for setting the cursor position at the time when the destination input key of the operation portion 4 is pressed as the destination, and 5M designates a map required from the map storage medium 1 when the destination is set. Read the data to the buffer memory 5A,
A route search unit that searches for the shortest route connecting the current position to the destination from the current position to the destination by the horizontal search method using the map data read to the buffer memory 5A.
Reference numeral 5P is a guide route storage unit that stores, as route guide data, a node data string in which node data forming the route searched by the route search unit 5M is arranged in the route order.

Reference numeral 5Q is a cursor position setting unit, which calculates cursor coordinates that change according to the operation of the scroll key in the map scroll mode. Reference numeral 5R is a power-saving power on / off unit, which turns on / off the supply of power to each of the above-described units described later as necessary.

Reference numeral 7 is the energy-saving unit, which is configured to cut off the power supply when the driver does not see the display or hears the guidance voice even when the Acc is on. Which includes a map image drawing unit 5B, a video RAM 5C, a video converting unit 5I, a voice synthesizing unit 5J, a D / A converting unit 5K, and an amplifier 5L. These parts are the power saving power on / off unit. 5R
Power is turned on and off by.

In the apparatus having the above construction, when the power is turned on, the current position detection section 3 inputs the vehicle position data and the vehicle direction data, and the map image drawing section 5B stores the map data including the vehicle position in the CD-ROM 1. To buffer memory 5
A map image is read out to A, and a map image with the vehicle position as the center and the north facing upward is video RA using the read map data.
It is drawn on M5C, and a vehicle position mark whose vehicle azimuth direction is directed to the center of the map image is drawn. Video RAM 5
The image drawn on C is read by the video conversion unit 5I, converted into a predetermined video signal, output to the CRT display device 2, and displayed on the screen.

Then, the user sets the current position as the starting point,
When you want to travel along the optimal route to your desired destination,
A map scroll operation is performed using the cursor keys of the operation unit 4 and the cursor position setting unit 5Q to search for a destination. At this time, when the operation of the cursor key is started, the map matching unit 5D initializes the current vehicle position as the initial cursor position, and then continuously changes the cursor position according to the operation of the cursor key.

When the destination input key of the operation unit 4 is pressed when the cursor is aligned with the destination, the destination setting unit 5N sets the cursor position at that time as the destination, and the route search unit 5M stores the destination data as destination data. Output. The route search unit 5M, to which the destination data is input, sets the detected current position as the starting point, and outputs the map data in the range from the starting point to the destination from the CD-ROM 1 to the buffer memory 5
The shortest route connecting the starting point to the destination in the read map data is read out using the road layer, and the result is searched for in the guide route storage unit 5.
Let P remember it. After that, the guide route in the area where the map image is drawn centered on the cursor position is read out, and the guide route that is thickly emphasized with a predetermined color is drawn on the map image.

The guide route searched as described above is once displayed as all routes, and when the vehicle starts traveling along the route, first, the route guidance at the present time is given by, for example, a voice saying "It is a road for a while". As described above, the power-saving power on / off unit 5R stops the power supply to the energy-saving unit 7 to save power consumption. In this case, the unit whose power is cut off is not necessary for “road driving”, including the map image drawing unit 5B, the video RAM 5C, the video converting unit 5I, the voice synthesizing unit 5J, the D / A converting unit 5K, and the amplifier 5L. As it is, there is no hindrance to "road driving".

While the power supply to the energy-saving unit 7 is stopped, the other units are still operating, of course, the own-vehicle position is detected by the own-vehicle position detecting means 3, and the guide route storage unit 5P is used. In order to display the position of the vehicle on the guide route read from the guide unit 5E, the guide unit 5E continues to operate by the input from the map matching unit 5D, and immediately when the power supply to the energy saving unit 7 is resumed, the display is immediately displayed. , It is in a state where the voice output can be executed.

When the vehicle travels and the vehicle position detected by the vehicle position detecting means 3 approaches a point such as the next guidance intersection within a predetermined distance, the guide portion 5E determines by the input from the map matching portion 5D. The guide unit 5E issues a signal to the power-saving power-on / off unit 5R to restart the power supply to the energy-saving unit 7, and each unit in the energy-saving unit 7 is supplied with power and restarts its operation. Is executed by the display and voice output.

After the normal passage of the guide point, the route guidance is again performed by voice such as "running on the road for a while", and the power-saving power on / off unit 5R supplies power to the energy-saving unit 7. Stop and save power consumption.

When the vehicle arrives at the destination by repeating the above-mentioned operation process, the user is informed of the fact and the power supply to the energy saving unit 7 is stopped.

When it is detected that the traveling route has deviated from the guide route, the guide unit 5E issues a signal to the power-saving power-on / off unit 5R to restart the power supply to the energy-saving unit 7, and the energy-saving unit. Each unit in 7 is supplied with power and restarts operation, so that route guidance is executed.

If necessary, it is possible to display the screen by key input by the user while the power supply to the energy saving unit 7 is cut off. Further, in this case, the screen displayed by key input is turned off by a user key input, or is automatically turned off in, for example, 3 minutes by providing a timer.

In the above-described embodiment, the voice guidance by the synthesized voice is provided in addition to the display screen by the display device, but the present invention can be used even if the voice guidance is not provided and only the display screen is provided. It goes without saying that it is possible.

[0031]

As described above, according to the present invention, in a vehicle-mounted navigation device with route guidance, when the route being traveled is "a road", the driver normally displays a display screen. I don't see it, and I don't hear voice guidance. Therefore, during this period, the power supply to the unit related to video and audio is turned off to save the power, so that the power consumption can be suppressed to about 50%. Further, since the video and the audio are restored by detecting the approach of an intersection or the like and the deviation from the route, the guidance can be performed without any trouble and the user can be guided to the destination.

[Brief description of drawings]

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

[Explanation of symbols]

1 Map storage media (CD-ROM, etc.) 2 CRT display device 3 Own vehicle position detection means 4 operation part 5 Navigation controller 5B Map image drawing unit 5C video RAM 5E Information Department 5I video converter 5J voice synthesizer 5H synthesis section 5K D / A converter 5L amplifier 5M route search unit 5N Destination setting section 5P guidance route storage 5R Power saving power on / off unit (power control unit) 7 Energy Saving Department

Claims (2)

(57) [Claims] 1. A map storage medium storing map data, a vehicle position detecting means for detecting a current position of a vehicle, a guide route storing means for storing a guide route to a desired destination, and the vehicle position. A map image drawing unit that draws a map image based on the current position of the vehicle detected by the detection unit, road data corresponding to the current position read from the map storage medium, and the guide route read from the guide route storage unit. A video RAM for storing the map image drawn by the map image drawing unit; a video conversion unit for converting the image data output by the video RAM into a predetermined video signal; and a video output by the video conversion unit. a display device for displaying the map image drawing unit, wherein the video RAM, the image converter, and the power supply for controlling the power supply to the display device And control means, wherein when the guide route from the current position ahead of the vehicle detected by the vehicle position detecting means requires the running of a road, the map image drawing unit by said power supply control means, said video RA
M, the image converter, and cut off the power supply to the display device, then, even if it detects that it has approached the point that requires induction, even when detecting that the travel route from the navigation route is out, the power supply An in-vehicle navigation device, comprising: a map image drawing unit, a video RAM, an image converting unit, and a guide unit for starting power supply to the display device by a control unit. 2. A map storage medium storing map data, a vehicle position detecting means for detecting a current position of a vehicle, a guide route storing means for storing a guide route to a desired destination, and the vehicle position. Current position of the vehicle detected by the detection means
And the current position read from the map storage medium.
Road data read from the guide route storage means
Map image drawing that draws a map image based on the guide route
Section and a view for storing the map image drawn by the map image drawing section.
The video data output from the video RAM and the video RAM is transferred to a predetermined video signal.
A display for displaying the image converter, the video output of the image converter which converts the No.
Device, voice synthesizing section for generating guide voice signal, amplifier for amplifying guide voice signal generated by the guide voice synthesizing section, map image drawing section, video RAM, video conversion
Section, the display device, the voice synthesizing section, and a power supply control means for controlling power supply to the amplifier, and a guide route ahead of the current position of the vehicle detected by the own vehicle position detection means can be driven along the road. In this case, the map image drawing unit and the video RA are controlled by the power control means.
Even when it is detected that the power supply to M, the image conversion unit, the display device, the voice synthesis unit, and the amplifier is cut off, and then the vehicle approaches a point requiring guidance, the traveling route deviates from the guidance route. And a guide unit for starting power supply to the map image drawing unit, the video RAM, the video conversion unit, the display device, the voice synthesis unit, and the amplifier by the power supply control unit. An in-vehicle navigation device characterized in that