JP3570457B2 - Vehicle navigation system - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention belongs to the technical field of a vehicle navigation device that provides a driver with information to a destination when traveling on an unfamiliar road.
[0002]
[Prior art]
The vehicle navigation device performs a route search from a current position or a designated departure point to a destination based on input of a destination or the like, and displays a road map on a display screen based on the searched optimum route. By displaying the route and the current position of the vehicle on a map, the driver is provided with information to the destination when traveling on an unfamiliar road.
[0003]
The conventional method related to this screen display displays a wide range map centering on the current position of the vehicle, displays the current position with an arrow or the like, and moves and drives the map as the current position of the vehicle moves. In general, a method of providing map information centering on a current position to a user is provided.
[0004]
[Problems to be solved by the invention]
However, the conventional screen display is a method in which the map information is displayed on the screen in a form viewed from directly above, like the map of the printed matter, so that the current position of the vehicle, the traveling destination, and the traveled route are all at the same magnification. When displayed, it is difficult for the driver to determine necessary information in the latest guidance, and because it displays more information than necessary in addition to the current position information, it is not easy to recognize information on the current position, It is not always satisfactory in terms of visibility. Accordingly, as shown in FIG. 14, the applicant changes the map information to the conventional map information while driving the vehicle, displays the road as a line having one width and three-dimensionally, and turns right and left on the route. Japanese Patent Application No. 7-217865 proposes a system that displays the traveling direction at a certain point on a display screen. In such a system, the shape of the road on which the vehicle travels is always displayed as a straight line, so it is difficult for the driver to determine the shape of the nearest road, for example, whether the road is a curved road or not. There is a problem that determination is difficult.
[0005]
The present invention solves the above-described problem, and expresses the route information around the current position of the vehicle three-dimensionally based on the road shape, thereby providing the current position of the vehicle and the route information ahead of the current position of the vehicle. It is an object of the present invention to provide a navigation device for a vehicle, which is displayed as the vehicle moves, and in which the route information at the time of driving can be easily recognized.
[0006]
[Means for Solving the Problems]
For this purpose, the vehicle navigation device according to the present invention includes a current position detecting unit that detects a current position of the vehicle, a unit that inputs a destination, an information storage unit that stores road data for searching a route, Route search means for searching for a route to a destination based on the road data stored in the information storage means; and route information around the current position of the vehicle based on the road shape searched by the route search means. A route information conversion unit configured to convert the route information into a three-dimensional route information visually; and an output display unit configured to output and display the route information converted by the route information conversion unit. the angle between the current position and the predetermined distance ahead of the position of the vehicle calculated at a period of, said angle performs curve drawing of a road in the case of more than a predetermined value, and when the angle is less than the predetermined value straight Performs drawing, has a conversion means for converting the line connecting the current position and a predetermined distance ahead of the position in both the curve drawing and straight line drawing lateral line and the left and right center line of the road, a road width by the converting means It is characterized in that the image is drawn so as to be gradually narrowed upward from the output display means.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram showing one embodiment of a vehicle navigation device to which the present invention is applied. The vehicle navigation device according to the present invention includes an input / output device 1 for inputting and outputting information relating to route guidance, a current position detecting device (current position detecting means) 2 for detecting information relating to the current position of the own vehicle, and is necessary for calculating a route. Storage device (information storage means) 3 which stores various navigation data and display / voice guidance data and programs (OS and / or applications) necessary for route guidance, necessary for route search processing and route guidance. It comprises a central processing unit 4 that performs display / voice guidance processing and controls the entire system. First, each configuration will be described.
[0008]
The input / output device 1 performs navigation processing according to the driver's will so that the driver can input guidance information and output guidance information from at least one of a voice and / or a screen when necessary. And a function to print out the processed data and the like. As means for realizing the function, the input unit includes a touch switch 11 and an operation switch (input means) for inputting a destination as a telephone number or coordinates on a map, and for requesting route guidance. Have. Of course, an input device such as a remote controller may be used. The output unit includes a display (output display unit) 12 that displays input data on a screen and automatically displays route guidance on a screen in response to a driver's request, and stores data and information processed by the central processing unit 4. A printer 13 for printing out data stored in the device 3 and a speaker 16 for outputting route guidance by voice are provided.
[0009]
Here, a voice recognition device for enabling voice input and a recording card reader for reading data recorded on an IC card or a magnetic card can be added. Further, a data communication device for exchanging data with an information source such as a personal computer in which driver-specific data such as map data and destination data are stored in advance can be added.
[0010]
The display 12 is composed of a color CRT or a color liquid crystal display, and includes all screens necessary for navigation, such as a route setting screen, a section map screen, and an intersection map screen based on map data and guidance data processed by the central processing unit 4. Are displayed in color, and buttons for setting route guidance, performing guidance during route guidance, and performing a screen switching operation are displayed on this screen. In particular, the passing intersection information such as the passing intersection name is displayed in color in a pop-up on the section map screen at any time.
[0011]
The display 12 is provided in the instrument panel near the driver's seat, and the driver can confirm the current position of the vehicle by looking at the displayed map and can obtain information on a route from now on. . The display 12 is provided with a touch switch 11 corresponding to the display of the function button, and is configured to execute the above-described operation based on a signal input by touching the button. The input signal generating means including the button and the touch switch constitutes an input section, but a detailed description thereof will be omitted here.
[0012]
The current position detecting device 2 detects or receives information on the current position of the vehicle, and includes an absolute direction sensor 24 including a geomagnetic sensor, a relative direction sensor 25 including a steering sensor, a gyro, and the like. It has a distance sensor 26 for detecting the traveling distance from the rotation speed of the GPS, a GPS receiver 21 using a satellite navigation system (GPS), and a communication device 5. The communication device 5 includes a VICS receiving device 22 and a data transmitting / receiving device 23, which are traffic information acquiring means. A VICS (Road Traffic Information System; Vehicle Information & Communication System) performs FM multiplexing (text) on road traffic information in real time. Broadcasting), radio beacons, and optical beacons are transmitted to vehicles. FM multiplexing transmits coarse information over a wide area, and information on radio beacons and optical beacons is detailed in a narrow area within a radius of about 10 km around the beacon. Information that can be received when the vehicle passes the beacon. The VICS transmission data includes the degree of congestion (for example, the degree of congestion such as impassability, congestion, congestion, heavy traffic, or normal congestion), the start position of congestion, the length of congestion, It is composed of regulations (construction information, road closures, etc.) and travel time (time required at a predetermined speed). The data transmitting / receiving device 23 is, for example, a mobile phone or a personal computer, and exchanges information necessary for navigation with a traffic information center (for example, ATIS) at the request of the driver.
[0013]
The information storage device 3 is an external storage device that stores a navigation program and data in an external storage medium such as a CD-ROM (hereinafter, simply referred to as a CD), an optical CD, an IC card, or the like. The program includes a map drawing unit, a route search unit, a route guidance unit, a current position calculation unit, a destination setting operation control unit, and the like, and an application unit for performing signal processing of navigation, an OS unit, and the like. A program for performing processing such as, display output control necessary for route guidance, a program for performing voice output control necessary for voice guidance and data necessary for the same, and display information required for route guidance and map display Data is stored. The data stores all data necessary for navigation, such as map data, intersection data, road data, and various types of guidance data.
[0014]
More specifically, a program (route searching means) for setting a destination and a passing point based on position information from the current position detecting device 2 and an input signal from the input device 11 and executing a route search using the searched road data. A program for converting the searched road data based on the traffic information acquired from the communication device 5 to execute the route search again, and a program for converting the searched route into a three-dimensional drawing (route information converting means) Alternatively, programs for determining map output, map matching, voice output timing and voice phrase content along a route are stored, and by activating the programs stored in the information storage device 3, the present invention provides Each function of the navigation is executed. That is, in the present embodiment, a program for realizing the functions of the present invention is stored in the information storage device 3 which is an external storage medium.
[0015]
The central processing unit 4 includes a CPU 40 for executing various arithmetic processing, and a flash memory 41 for reading and storing programs from a CD of the information storage device 3. The flash memory 41 erases an existing program and makes it rewritable even if the program of the CD is changed. Also, a first ROM 43a storing a program (program reading means) for performing a program check and update process of the flash memory 41, the set point coordinates of the destination, the road code No. A RAM 42 for temporarily storing searched route guidance information and data being subjected to arithmetic processing, and a second ROM 43b for storing display information data necessary for route guidance and map display. Note that a program for performing the above-described update processing may be stored in an external storage device.
[0016]
Further, an image memory 44 in which image data to be used for screen display on a display is stored, an image processor 45 for extracting image data from the image memory based on a display control signal from the CPU 40, performing image processing, and outputting the processed image to the display 12. A voice processor 46 for synthesizing voice, phrase, one sentence, sound, etc. read from the RAM 42 based on a voice output control signal from the CPU 40, converting the synthesized voice into an analog signal, and outputting the analog signal to the speaker 16; A communication interface 47 for exchanging output data, a sensor input interface 48 for receiving a sensor signal of the current position detection device 2, a clock 49 for writing date and time in internal diagnostic information, and the like are provided.
[0017]
In the central processing unit 4, when data acquired by each sensor of the current position detection device 2 is fetched from the sensor input interface 48, the CPU 40 calculates the current position coordinates at regular intervals based on the data, and temporarily stores the coordinates. Write to RAM42. The current position coordinates are obtained by performing a map matching process in consideration of detection errors of various data. The output values of the various sensors are constantly corrected. Here, route guidance is performed by screen display and voice output, and the presence or absence of voice output can be selected by the driver.
[0018]
FIG. 2 is a diagram showing a part of a guidance (search) road data file stored in the information storage device 3 which is data necessary for calculating a route by the route search unit and performing route guidance. As shown in FIG. 2 (A), for each of the number of roads n, there are data of road number, length, road attribute data, address of shape data, size, address of guidance data, and size data. The road number is an identification number that is set for each of the roads included in the map, for each of the roads between the branch points such as the intersections, for each of the outbound and return routes. The road attribute data is data indicating a road type such as an elevated road, an underpass, an expressway, a national road, a general road, and a toll road. The shape data is data indicating the shape of the road. As shown in FIG. 2B, when each road is divided into a plurality of nodes (nodes), the number of nodes m is determined from the east longitude and the north latitude. And coordinate data. The guidance data includes an intersection (or junction) name, the presence or absence of a traffic light, landmarks (traffic signs, signboards such as gas stations and convenience stores) data, caution point data (railroad crossings, tunnels, etc.), road name data, and destination data. Consists of
[0019]
FIG. 3 is a diagram for explaining the flow of the entire system of the vehicle navigation device according to the present invention. In step S1, an initialization process is performed. The CPU 40 reads a navigation program from the CD-ROM, stores the navigation program in the flash memory 41, and performs a process of first detecting the current position by the current position detection device 2 according to the navigation program. A map around the position is displayed, and the name of the current position is displayed (step S2). Next, a process of setting a destination using a telephone number, an address, a facility name, a registered point, and the like is performed (step S3), and a route search process from the current position to the destination is performed (step S4). The route up to the destination is set as guide road number data in which the guide road numbers are arranged as shown in FIG. When the route is determined, route guidance / display processing is performed until the vehicle arrives at the destination while tracking the current position by the current position detection device 2 (step S5).
[0020]
The present invention relates to a process of converting and displaying the current position of the vehicle and the route information in front of the current position in the guidance / display process of step S5. First, the route information of the present invention will be described with reference to FIGS. One embodiment of the processing in the conversion means will be described. FIG. 5 is a basic flowchart showing one embodiment of the processing in the present invention. In step S11, the current position P 'coordinates and orientation of the vehicle are acquired by the current position detection device 2, and in step S12, the current position P matching on the route searched from the current position P' coordinates is calculated. Next, the coordinates of a point Q located a predetermined distance Lm (for example, 10 to 50 m) ahead of the current position P on the route searched in step S13 are calculated (as shown in FIG. Remembered). Next, in step S14, an azimuth difference D _PQ between the current position P and a point Q on the route ahead of Lm, and an azimuth difference D _pq between the current position p on the previous route and the point q on the route ahead Lm. (Ie, the intersection angle between the straight line PQ and the straight line pq) is equal to or greater than a predetermined angle (for example, 2 to 10 °). If the angle is equal to or larger than the angle, the road curve is drawn in accordance with the angle difference.
[0021]
6 and 7 are flowcharts showing the curve drawing process of FIG. 5, and FIGS. 8 and 9 are diagrams for explaining the process of FIGS. 6 and 7, respectively. FIG. 6 is a process for drawing the center line (X, Y) of the curved road in FIG. 9. In step S21, the absolute coordinates (x ₀ , y ₀ ) and azimuth of the current position P are acquired, and in step S22, The azimuth of the current position Q ahead of the current position P by a predetermined distance is acquired. Then, the current position P in step S23, obtains a misorientation dang of Q, an arbitrary point T (CTRX, CTRY) on x = _{x 0} at step S24 to acquire. Then, calculations in steps S25 to S27 are performed.
[0022]
That is, in FIG. 8, the point S (CRS) of the azimuth difference dang with respect to the point T (CTRX, CTRY). Assuming that the distance to (x, CTRY) is dx, the following equation is established at a point (x, y) on a straight line connecting the point P and the point S.
[0023]
dx = CTRY * Tang dang
CRS x = CTRX−dx
Then, the following equation is used to convert the straight line (x, y) into a curve (X, Y) shown in FIG.
[0024]
X = CRS ^{x + dx * y 2 / CTRY} 2
Y = y
By substituting each point on (x, y) into the above equation, the center line (X, Y) of the road shown in FIG. 9 can be drawn.
[0025]
Next, according to FIG. 7, based on the center line (X, Y) of the road, left and right side lines (X ′, Y) such that the road width converges to 0 toward the point S as shown in FIG. Ask. In FIG. 9, a predetermined point on the Y-axis on the screen is set to k, and a road width at the point k is set to a. This is for drawing a road having a desired width substantially at the center of the screen. In steps S32 to S34,
X '= X ± a * (CTRY-Y) / (CTRY-k)
By substituting the values of Y = _{0 to b} using the equation, the values of X ′ _{0 to} X ′ _b are obtained,
By connecting the values of (X ′ _{0 to} X ′ _b , Y _{0 to} Y _b ), the left and right side lines (X ′, Y) shown in FIG. 9 can be drawn.
[0026]
In FIG. 8, the straight line drawing of the road may be performed by drawing the center line of the road and a plurality of left and right side lines as straight lines toward the lower part of the screen with the predetermined point T as the center.
[0027]
FIG. 10 shows an example of a screen when a road is drawn in a curved line. By drawing a plurality of side lines on the left and right of the center line of the road, the road is displayed three-dimensionally, and the screen is displayed in the same manner as the actual vehicle turns. Above you can see the road bend.
[0028]
FIG. 11 shows an example of a screen when a road is drawn in a straight line. Based on the route information from the current position of the vehicle to a position ahead of a predetermined distance, the road is not only drawn three-dimensionally, but also a plurality of roads are drawn on the drawn map. The route information of is displayed. For example, during high-speed driving, the names to be guided in the direction of travel such as interchanges, junctions, and parking areas may be changed to the remaining distance from the current position of the vehicle to the displayed name and a gas station installed at the displayed name. High-speed information of the facility is displayed. In FIG. 11, high-speed information of "Moriyama PA" closest to the current position of the vehicle is displayed, but the user designates "Kasugai IC" or "Komaki JCT" which is a destination ahead of "Moriyama PA". By doing so, high-speed information of "Kasugai IC" or "Komaki JCT" can be displayed. Therefore, there is no complicated map on the screen, and the current position of the vehicle and the route information ahead of the current position are displayed in three dimensions, so that it is easy to check the map information at hand while driving, and the driver can drive safely and accurately. Be able to operate.
[0029]
12 and 13 show another embodiment of the processing in the route information conversion means in the present invention. FIG. 12 is a flowchart of the display processing, and FIG. 13 is a view for explaining the data configuration. In the present embodiment, as shown in FIG. 13, a conversion map for converting a straight line (x, y) into a curve (X, Y) for each direction difference dang is prepared. 12, steps S51 to S53 are the same as the processing in FIG. In step 54, a corresponding list is selected from the conversion map data shown in FIG. 13 based on the azimuth difference dang. In step S55, (X, Y) is obtained from the list based on (x, y), and in step S56, By connecting the (X, Y) thus obtained and smoothing the line connected in step S57, the center line of the curved road is displayed. For the left and right side lines, (X, Y) obtained in step S56 can be obtained by performing the processing of the above-described flowchart shown in FIG.
[0030]
The embodiments of the present invention have been described above. However, the present invention is not limited to the embodiments, and it is needless to say that various modifications can be made.
[0031]
【The invention's effect】
As is apparent from the above description, according to the present invention, the route information around the current position of the vehicle is three-dimensionally represented based on the road shape, so that the current position of the vehicle and the route information ahead of the current position of the vehicle can be obtained. Is displayed with the movement of the vehicle, so that the route information at hand during driving can be easily recognized.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing an example of a vehicle navigation device to which the present invention is applied.
FIG. 2 is a view showing a guide road data file according to the present invention.
FIG. 3 is a diagram for explaining a flow of the entire system of the vehicle navigation device according to the present invention.
FIG. 4 is a diagram for explaining guide road number data obtained by the route search in FIG. 3;
FIG. 5 is a basic flowchart showing one embodiment of a process in a route information conversion unit of the present invention.
FIG. 6 is a flowchart showing a curve drawing process of FIG. 5;
FIG. 7 is a flowchart showing a curve drawing process of FIG. 5;
FIG. 8 is a diagram for explaining the processing in FIG. 6;
FIG. 9 is a diagram for explaining the process of FIG. 7;
FIG. 10 is a diagram showing an example of a screen when a road is drawn as a curve.
FIG. 11 is a diagram illustrating an example of a screen when a road is drawn in a straight line.
FIG. 12 is a flowchart showing another embodiment of the processing in the route information conversion means of the present invention.
FIG. 13 is a diagram for explaining the data configuration of FIG. 12;
FIG. 14 is a diagram showing a display screen for explaining the problem of the present invention.
[Explanation of symbols]
2 ... current position detecting means, 3 ... information storage means, 11 ... input means 12 ... output display means

Claims (3)

Current position detecting means for detecting the current position of the vehicle,
Means for entering a destination;
Information storage means for storing road data for searching for a route;
Route search means for searching for a route to a destination based on the road data stored in the information storage means;
Route information conversion means for converting the route information around the current position of the vehicle into route information visually and stereoscopically represented, based on the road shape searched by the route search means;
Output display means for outputting and displaying the path information converted by the path information conversion means,
The route information conversion means calculates an angle between the current position of the vehicle and a position ahead of a predetermined distance at a predetermined cycle, and draws a curve of a road when the angle is equal to or more than a predetermined value, and calculates the angle at a predetermined value. In the case where the number is less than or equal to, a straight line drawing is performed, and in both the curve drawing and the straight line drawing, a line connecting the current position and a position ahead of the predetermined distance is converted into a center line of the road and left and right side lines, A vehicle navigation apparatus, wherein the conversion means draws the road width so as to gradually decrease toward the upper side of the output display means. The vehicular navigation device according to claim 1, wherein the conversion means obtains a center line and left and right side lines based on a calculation formula. 2. The vehicular navigation device according to claim 1, wherein the conversion means obtains a center line and left and right side lines based on the conversion map.

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