JP2777484B2 - In-vehicle navigator route guidance method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route guidance method for an in-vehicle navigator, and more particularly to a route guidance method for an in-vehicle navigator that provides route guidance from an origin to a destination along an optimal guidance route.

[0002]

2. Description of the Related Art There is an on-vehicle navigator that provides guidance for driving a vehicle so that a driver can easily reach a desired destination. In this in-vehicle navigator, a vehicle position is detected, map data around the vehicle position is read from a CD-ROM, a map image is drawn on a V-RAM, and a vehicle position mark is superimposed on a predetermined position on the map image. Draw,
While converting the image in the V-RAM into a video signal, the image is output to a CRT display device and displayed on a screen. Then, as the current position changes due to the movement of the vehicle, the vehicle position mark on the screen is moved, or the vehicle position mark is fixed at the center of the screen and the map is scrolled, so that the map around the vehicle position is always displayed. Information can be understood at a glance.

The map stored in the CD-ROM is divided into regions of appropriate longitude and latitude widths according to the scale level, and roads are represented by vertices (nodes) represented by longitude and latitude coordinates. ). A portion connecting two or more nodes is called a link. As shown in FIG. 9, the road data included in each map is road link data RLDT,
The road link data RLDT is provided with node data NDDT and intersection data CRDT. Among them, the road link data RLDT gives attribute information of the road link.
It is composed of data such as a number on the DT, a road name, and a road type. The intersection data CRDT is, for each intersection on the map, a set of numbers on the node data NDDT of nodes closest to the intersection on the link connected to the intersection (referred to as an intersection configuration node), and the node data NDD.
T is a list of all nodes on the map, coordinate information (longitude, latitude) for each node, an intersection identification flag indicating whether or not the node is an intersection, and indicates intersection data if the node is an intersection; It is composed of a pointer or the like indicating the road link to which the node belongs.

Some in-vehicle navigators have a route guidance function of providing route guidance along an optimal guidance route from a departure point to a destination. In such route guidance,
If the driver sets the departure point and destination before traveling, the CD-
A simulation calculation is performed with reference to the map data in the ROM, and for example, an optimal guide route connecting the departure place and the destination at the shortest distance is obtained, and a node sequence constituting the guide route, the starting departure place data at the head and the tail end The guidance route data combined with the destination data is stored in the guidance route memory.

During driving, the driver searches for a guidance route in the map display area of the screen from the node sequence in the guidance route memory and displays the guidance route in a different color from other roads. Is trying to figure out which road to drive.

[0006]

However, if the scale of the map displayed on the screen is large or the roads are complicated, the vehicle may not be displayed simply by displaying the guidance route in a different color from other roads. In some cases, it is not possible to know in which direction to travel at an intersection existing ahead of the traveling direction.

Accordingly, an object of the present invention is to provide a route guidance method for an in-vehicle navigator in which a driver can easily and surely know which direction to travel at each intersection on a guidance route. is there.

[0008]

According to the present invention, the present invention refers to, based on vehicle position information, a node sequence of a guidance route storage device or a node sequence of a guidance route storage device and map data of a map data storage device. Means for determining a direction to travel at an intersection closest to the vehicle position as viewed in the vehicle traveling direction on the guidance route, and means for providing a predetermined intersection traveling direction guide based on the determined traveling direction Means for detecting the last node through which the vehicle has passed, based on the vehicle position information, and whether the detected node matches the intersection in the intersection traveling direction guidance or the intersection in the node row of the guidance route storage means The present invention is characterized in that a means is provided for ending the current intersection traveling direction guidance when it coincides with the preceding node on the guidance route.

[0009]

According to the present invention, based on vehicle position information, referring to the node sequence of the guidance route storage means or the node sequence of the guidance route storage means and the map data of the map data storage means, the vehicle is guided on the guidance route. The direction to travel at the intersection closest to the vehicle position in the traveling direction is determined, and based on the determined traveling direction, a predetermined intersection traveling direction guidance is performed. The node that has passed last is detected, and the detected node matches the intersection in the intersection traveling direction guidance or the node that is earlier on the guidance route than the intersection in the node row of the guidance route storage means. At this time, the current intersection driving direction guidance ends.
With this, the driver can be guided in the direction to travel at the next intersection in the vehicle traveling direction on the guidance route, and when the vehicle passes the intersection, the vehicle position information jumps over the intersection and changes. Also, after completing the current intersection driving direction guidance, new driving direction guidance for the next intersection can be performed, so that the driving direction guidance for each intersection on the guidance route can be reliably executed, and the driver can It is possible to easily and surely know in which direction to travel at each intersection on the route.

[0010]

1 is a block diagram of a main part of an on-vehicle navigator embodying a route guidance method for an on-vehicle navigator according to the present invention.

In FIG. 1, reference numeral 1 denotes a CD-ROM serving as map data storage means, and reference numeral 2 denotes an operation panel, which includes left, right, up, and down cursor keys, a route guidance mode setting key, a departure place setting key, and a destination. A setting key, a key for map search, enlargement / reduction, a start key, and the like are provided. Reference numeral 3 denotes an azimuth sensor that detects the azimuth of the vehicle traveling direction viewed from a predetermined reference azimuth and outputs an azimuth signal. 4 denotes a distance sensor that outputs a pulse indicating that the vehicle has traveled a certain distance each time the vehicle travels a certain distance. The vehicle position calculation CPU by navigation calculates the current position (longitude, latitude) of the vehicle by integrating from the departure point using the respective signals input from the direction sensor 3 and the distance sensor 4. Reference numeral 6 denotes a CRT display device, which inputs a video signal and displays a map on a screen together with a cursor mark, a vehicle position mark, an enhanced guidance route, an intersection guidance image, and the like.

Numeral 10 denotes a navigation controller having a microcomputer structure, which determines an optimal guidance route from a departure point and a destination by simulation calculation, or displays a map image around the vehicle position as necessary with a cursor mark, a vehicle position mark, and enhanced guidance. CR with route, intersection guidance image, etc.
The information is displayed on the screen of the T display device 6, and the intersection guidance information is output as voice. Among them, 11 is CD-R
A buffer memory 12 for temporarily storing map data read from the OM 1, a current position correction unit 12 for correcting the current position by map matching based on a projection method, and each time the current position data is input from the vehicle position calculation CPU 5, Correct on a nearby road by referring to the map data. Reference numeral 13 denotes an existing link detection unit which inputs corrected current position data from the current position correction unit 12 and an azimuth signal from the azimuth sensor 3,
With reference to the road data in the map data (see FIG. 9), nodes existing immediately before and immediately after the vehicle position on the road on which the vehicle is currently traveling as viewed in the vehicle traveling direction are defined as front nodes and rear nodes, respectively. , An existence link composed of a pair of the front node and the rear node is detected. The front node and the rear node consist of longitude and latitude coordinates.

Reference numeral 14 denotes a cursor position calculation unit, which corresponds to the center of the map on the screen when a map selection operation or a cursor operation is performed by a cursor key on the operation panel 2, a key for map search, an enlargement / reduction key, or the like. Calculate the longitude and latitude to be output as the cursor position. Reference numeral 15 denotes a map drawing control unit which stores desired map data (may include peripheral map data) selected by a key for map search, enlargement / reduction, etc. on the operation panel 2 before starting traveling. The map data is read from the ROM 1 to the buffer memory 11 and a map image is drawn on a first V-RAM, which will be described later, and new map data is added as necessary as the cursor position input from the cursor position calculator 14 changes in response to the cursor operation. To CD-ROM
While reading from 1 to the buffer memory 11, the map image in the first V-RAM is rewritten so that the cursor position is always at the center, and a cursor mark is drawn at the center of the first V-RAM. Further, the map drawing control unit 15 is running (after the start key of the operation panel 2 is pressed), and
As the corrected current position data output from the CPU changes, new map data is read out from the CD-ROM 1 to the buffer memory 11 as needed, and the map image in the first V-RAM is rewritten so that the current position becomes the center. In addition, the map drawing control unit 15 draws a vehicle position mark in the center of the first V-RAM based on the corrected current position data during traveling, and in the route guidance mode, stores the guidance position data stored in the guidance route memory described later. From among them, guide route data that falls within the range of the map image currently drawn on the first V-RAM is input, and a guide route highlighted in a color different from that of other roads is drawn.

Reference numeral 16 denotes a departure / destination setting unit, which is set to a route guidance mode on the operation panel 2 before starting traveling, and after the cursor at the center of the screen coincides with the departure point by operating the operation panel 2, When the departure place setting key is pressed, the output of the cursor position calculation unit 14 at that time is set as the departure place data, and after the cursor at the center of the screen is matched with the destination by operating the operation panel 2, the destination is set. When the setting key is pressed, the output of the cursor position calculator 14 at that time is set as destination data.

Reference numeral 17 denotes a guide route search unit, which inputs departure place data and destination data from the departure place / destination setting unit 16 when a departure place and a destination are set in the route guidance mode. , Read various map data from the starting point to the destination from the CD-ROM 1 to the buffer memory 11 and perform simulation calculations on various routes with reference to the read map data, for example, using the shortest distance as an index, An optimal guidance route from the departure point to the destination is determined, and a series of node trains (each node includes longitude and latitude coordinates and an intersection identification flag indicating whether or not the intersection exists) constituting the guidance route is determined as the departure point. Along with the data and the destination data, it is stored in a later-described guidance route memory as guidance route data. Each node in the node sequence is extracted from a node list of map data (see NDDT in FIG. 9).

Reference numeral 18 denotes a guidance route memory for storing guidance route data. The node sequence obtained by the guidance route search unit 17 is, for example, 16 except for the departure place data and the destination data.
³ when composed -2 nodes, as shown in FIG. 2, the departure point data is stored in the address F000 _H, address F
001 _H ~FFFE The _H, closest node departure on the guide route to the address F001 _H, address F002 _H
The node sequence is sequentially stored in the order of the node closest to the departure place on the guidance route. Then, the destination data is stored at the end of the address FFFF _H.

In this embodiment, the guidance route memory 1 is used.
As shown in FIG. 3, the departure point data and the destination data stored in the departure point / destination 8 are the actual departure point S and destination O set by the departure point / destination setting section 16 (these are usually map data. shall be the node N _S and N _O extension on the nearest guide route to the node do not match) (longitude, including intersection identification flag indicating whether or not coordinate and the intersection of latitude).

Reference numeral 19 denotes a collating unit, and the existence link detecting unit 1
3, the existing link (front node and rear node) is input and collated with the guidance route data stored in the guidance route memory 18, and it is determined whether or not there is the same node as the front node and the rear node. Determine if it is above.

Reference numeral 20 denotes an extraction unit, which refers to the node sequence stored in the guidance route memory 18 based on the forward node input from the presence link detection unit 13 when the vehicle is on the guidance route, and determines the vehicle traveling direction. , The intersection node closest to the vehicle position as seen in the above, and the entry node and the exit node for the intersection node are extracted. Specifically, the intersection identification flag in the node column is checked, and when the intersection identification flag of the same node as the preceding node is set, this node is extracted as the intersection node closest to the vehicle position, If the intersection identification flag of the same node as the front node is off, the node with the first intersection identification flag that has the higher address than the same node as the front node is set to the intersection closest to the vehicle position. Extract as a node. Then, the node at the address before the extracted intersection node is set as the entry node, and the node at the address after the extracted intersection node is set as the exit node.

It should be noted that in the node row of the guidance route memory 18,
When the intersection identification flag is not included, the guidance route memory 1
8 is read out sequentially from the node at each address after the same node as the front node, and the node list ND in the map data
The same node in the DT (see FIG. 9) is searched to check the intersection identification flag, and the node where the intersection identification flag is set first is extracted as the intersection node closest to the vehicle position.

Reference numeral 21 denotes a traveling direction calculator, and an extractor 20
Based on the intersection node, the entry node, and the exit node extracted in (1), the direction to travel at the intersection (straight, left turn, right turn) is detected from these positional relationships. In particular,
As shown in FIG. 4, the angle θ of the escape node is determined clockwise with the intersection node as the center and the half-line extended from the intersection node in the direction of the entry node as the reference direction. When 0 ° ≦ θ ≦ 135 °, turn left. When 135 ° <θ <225 °, go straight. When 225 ° ≦ θ <360 °, turn right.

Reference numeral 22 denotes a distance calculation unit. When the vehicle is on a guidance route, the guidance route memory 1 is based on the corrected current position data and the forward node detected by the existing link detection unit 13.
The distance along the guidance route from the vehicle position to the intersection node extracted by the extraction unit 20 is obtained with reference to the node sequence No. 8.

Reference numeral 23 denotes a passage determination unit, and the vehicle is connected to the extraction unit 2
It is determined whether or not the vehicle has passed the intersection node extracted at 0. Specifically, the backward node detected by the existence link detecting unit 13 matches the intersection node extracted by the extracting unit 20, or the backward node is selected by the extracting unit 20 in the node sequence of the guidance route memory 18. It is determined that the vehicle has passed through the intersection when it matches a node ahead of the extracted intersection node on the guidance route (a node having a larger address than the intersection node extracted by the extraction unit 20).

Reference numeral 24 denotes an intersection guidance control unit,
9, when the vehicle has been detected on the guidance route or when the passage determination unit 23 determines that the vehicle has passed through a certain intersection while riding on the guidance route, an extraction command is output to the extraction unit 20. Then, referring to the road data in the map data based on the intersection node input from the extraction unit 20, all other nodes (intersection constituent nodes) forming a link with the intersection node are obtained, and the traveling direction calculation is performed. The travel direction information is input from the unit 21 and the distance information is input from the distance calculation unit 22. The second V-RAM described later stores an enlarged shape of the intersection based on the intersection node and the intersection configuration node, and a predetermined traveling based on the traveling direction information. Direction arrow pattern and travel direction characters (one of "straight ahead", "left turn", "right turn"), approach distance to intersection based on distance information (such as "あ と m") Draw the intersection running direction guide image including, to output to the combining unit, which will be described later. Also, the intersection guidance control unit 24 determines that the distance to the intersection is 150 m, 100 m.
When the vehicle passes either point m or 50m, please go straight ahead (or turn left or right) 150m ahead, go straight ahead (or turn left or right 100m ahead), " Please go straight (or turn left or right) at a distance of 50 m ”to a voice synthesizing unit to be described later.

Reference numeral 25 denotes a first V-RAM, which is a map image drawn by the map drawing control unit 15 (including a cursor mark when a cursor is operated before starting driving, and a vehicle position mark when driving in the route guidance mode). , And other guidance routes that are different in color from other roads). 26 is the second V-RA
M, and stores the intersection traveling direction guidance image drawn by the intersection guidance control unit 24. Reference numeral 27 denotes a synthesizing unit which normally outputs a map image read from the first V-RAM 25, and when a synthesis command is input from the intersection guidance control unit 24, a second map image is read from the first V-RAM 25.
The intersection traveling direction guidance image read from the V-RAM 26 is synthesized and output.

It is assumed that the intersection traveling direction guide image drawn on the second V-RAM 26 has a size of, for example, one-twelfth of the screen and is synthesized by the synthesizing unit 27 at the upper left corner of the map image.

Reference numeral 28 denotes a video conversion unit that converts the image data output from the synthesis unit 27 into a video signal and outputs the video signal to the CRT display device 6.

Reference numeral 29 denotes a voice synthesizing unit. When a voice output command is input from the intersection guidance control unit 24, according to the type of the voice output command, "go straight (or turn left or right) at 150 m ahead by voice synthesis". Please "or" 1
Go straight ahead (or turn left or right) at a distance of 00 m "or" Go straight (or turn left or right) at a distance of 50 m ". Reference numeral 30 denotes an amplifier for amplifying the audio signal input from the audio synthesis unit 29;
Is a speaker for converting the audio signal amplified by the amplifier 30 into sound.

FIGS. 5 and 6 are flowcharts showing the operation of the navigation controller 10, FIG. 7 is an explanatory diagram of an intersection traveling direction guidance operation by the navigation controller 10, and FIG. 8 is an explanatory diagram of a display screen of the CRT display device 6. Hereinafter, description will be made with reference to these figures.

First, when a map of a desired area is selected at a desired scale by operating a map search and a key for enlargement / reduction on the operation panel 2, the map drawing control unit 15 reads the desired map from the CD-ROM 1. The data is read into the buffer memory 11 and a map image is drawn on the first V-RAM 25. The map image data drawn on the first V-RAM 25 is output to the video conversion unit 28 via the synthesizing unit 27, and is converted into a video signal by the video conversion unit 28, so that the CRT display device 6
Output to The CRT display device 6 displays a map on the screen based on the input video signal (steps 101 and 102 in FIG. 5). Subsequently, when the cursor key of the operation panel 2 is operated after the setting operation of the route guidance mode is performed on the operation panel 2, the cursor position calculation unit 14 calculates the cursor position (longitude and latitude coordinates) (step S1). 103-10
6) In accordance with the change in the cursor position, the map drawing control unit 15 reads the predetermined map data from the CD-ROM 1 to the buffer memory 11 and draws the map image in the first V-RAM 25 so that the center is always the cursor position. At the same time, a cursor mark is drawn at the center of the first V-RAM 25. As a result, the map on the screen moves in accordance with the cursor operation while the cursor mark is displayed at the center of the screen (steps 107 and 108).

When the cursor mark on the screen reaches the destination, the cursor operation is temporarily stopped, and the destination setting key of the operation panel 2 is pressed. Is set and registered as destination data (steps 109 and 110). Subsequently, the cursor is operated again to move the map on the screen, and when the cursor mark comes to the departure place, the cursor operation is temporarily stopped, and the departure place setting key of the operation panel 2 is pressed. Part 1
6 sets and registers the cursor position data output from the cursor position calculator 14 at that time as departure point data (steps 112 and 113).

When the setting and registration of the departure place data and the destination data have been completed in this way, the guidance route search section 17 uses the CD-ROM 1 to change from the departure place to the destination based on the departure place data and the destination data. The simulation calculation is repeated while reading out the map data to the buffer memory 11 to search for an optimal guidance route using, for example, the shortest distance as an index. It is stored in the guidance route memory 18 together with the node N _s (see FIG. 3) and the last destination data (here, the node N _O , see FIG. 3) (steps 114 to 116). When there are 16 ³ -2 nodes (excluding the departure place data and the destination data) constituting the guide route, the contents of the guide route memory 18 are as shown in FIG.

Next, when the start key is pressed on the operation panel 2, the map drawing control unit 15 reads out the map data around the departure place from the CD-ROM 1 to the buffer memory 11, and sets the first V-map so that the center becomes the departure place. A map image is drawn on the RAM 25, and a vehicle position mark is drawn on the center of the first V-RAM 25. At this time, a map around the departure point with the vehicle position mark at the center departure point is displayed on the screen (steps 117 to 119). Then, the map drawing control unit 15 reads out nodes (including departure place data) included in the map display area of the screen from the guidance route data stored in the guidance route memory 18 and based on these data, other roads. The emphasis guidance route for route guidance is drawn on the first V-RAM 25 in a color different from that of the first V-RAM 25 (step 12).
0). As a result, the guidance route is displayed in a color different from that of the other roads on the screen, so that it is possible to see at a glance which road should be run.

When the vehicle starts running, the vehicle position calculating CPU 5 calculates the current position of the vehicle and outputs the current position data to the current position correction unit 12 every time the vehicle travels a predetermined distance. Each time the current position data is input, the current position correction unit 12 corrects the current position to be on the road by map matching by the projection method, and sends the corrected current position data to the map drawing control unit 15 and the existing link detection unit 13. Output (steps 121, 1
22). Upon input of the corrected current position data, the map drawing control unit 15 reads predetermined map data including the corrected current position data from the CD-ROM 1 into the buffer memory 11 so that the center is the vehicle position on the first V-RAM 25. A map image is drawn, and a vehicle position mark is drawn in the center of the first V-RAM 25. Then, of the guidance route data stored in the guidance route memory 18, the node and the departure place data in the map display area of the screen are read out, and the first V-RAM 25 is displayed in a color different from other roads based on these data. The guide route is drawn above. As a result, the map on the screen moves so that the center is always the vehicle position as the vehicle travels (steps 123 to 1).
25).

On the other hand, the existing link detecting unit 13 which has input the corrected current position data refers to the road data in the map data stored in the buffer memory 11 together with the azimuth signal input from the azimuth sensor 3 to check the vehicle. Is a node that exists on the road on which the vehicle is currently traveling and is located immediately before when viewed in the vehicle traveling direction,
A node that exists immediately after the vehicle is viewed in the vehicle traveling direction is searched, and an existing link composed of a pair of the front node and the rear node is detected as a front node and a rear node, respectively, and a matching unit 19, an extraction unit 20, a distance calculation unit 22, and outputs it to the passage determination unit 23 and the like (step 126). First, the forward node node N _1, the rear node becomes node N _S (see FIG. 7).

Upon input of the existence link, the collating unit 19 collates the forward node and the backward node with the guidance route data stored in the guidance route memory 18, and the same node exists in each of the forward node and the backward node. It is determined whether the vehicle is on the guidance route by checking whether the vehicle is on the route (step 201 in FIG. 6). When it is determined that the vehicle is on the guidance route, the intersection guidance control unit 24 has not guided the intersection in the traveling direction (NO in step 202).
Determination), and gives an extraction command to the extraction unit 20. Upon receiving the extraction instruction, the extraction unit 20 refers to the node sequence stored in the guidance route memory 18 based on the front node input from the existence link detection unit 13 and moves to the nearest vehicle position in the vehicle traveling direction. An intersection node related to a certain intersection and an entry node and an exit node for the intersection are extracted (step 203). Here, as shown in FIG. 7, the intersection as viewed in the vehicle traveling direction is closest to the vehicle position is CP _1, shall intersection node N _3, ingress node N _2, is escaped node N ₄ is extracted (Wakashi, when intersection as viewed in the vehicle traveling direction is closest to the vehicle position is the node N _1, enters node N _S, the escape node N _2).

When the extraction operation by the extraction unit 20 is completed, the traveling direction calculation unit 21 performs a predetermined calculation based on the intersection node N ₃ , the entry node N ₂ , and the exit node N ₄ to determine the positional relationship between these nodes. Then, the direction to travel at the intersection is determined by dividing the cases as shown in FIG. 4 (step 204). Here, the determined traveling direction is a left turn. Further, the distance calculation unit 22 refers to the node row of the guidance route memory 18 based on the corrected current position data input from the current position correction unit 12 and the forward node detected by the existing link detection unit 13, and calculates the intersection from the vehicle position. determining the distance along the guide route to CP ₁ (step 205). Here, it is assumed that the distance is 106 m.

Next, the intersection guidance control unit 24 refers to the road data in the map data based on the intersection node N ₃ input from the extraction unit 20, and all other nodes forming links with the intersection node N _3. (Intersection configuration node)
N ₂ , N ₄ , N _a , and N _b are obtained, the driving direction information (left turn) is input from the driving direction calculation unit 21, and the distance information (106 m) is input from the distance calculation unit 22.
The -RAM26, expanded configuration of intersections CP ₁ based on the intersection node and the intersection configuration node, the direction of travel arrow pattern and direction of travel character "left" represents a left turn based on the traveling direction information, based on the distance information intersection "after 106m" C
After drawing a intersection running direction guide image containing the approach distance character to P _1, and outputs the combined command to the combining unit 27 (step 206). However, intersection guidance control unit 24, the distance is 150m to the intersection CP _1, 100 m, since both the 50m not also pass through the point, the audio output command is not output (determination of NO at step 207).

The synthesizing section 27 which has input the synthesizing command outputs the first V
-A second V-RAM is added to the map image read from the RAM 25.
The intersection driving direction guidance image read out from 26 is synthesized and output to the video conversion unit 28. As a result, on the screen of the CRT display device 6, as shown in FIG. 8A, the intersection traveling direction guidance image is displayed in the map image. Therefore,
Driver is found to be able to travel toward the destination correctly induction path above if left at the intersection CP ₁ in the 106m away. If the traveling direction calculated by the traveling direction calculation unit 21 is straight ahead, the screen becomes as shown in FIG.
(3)

After determining NO in step 207, the navigation controller 10 proceeds to step 121 in FIG.
The next current position data is input from the vehicle position calculation CPU 5 to correct the current position, move the map according to the change in the current position, rewrite the vehicle position mark and the emphasized guidance route, detect the existing link, and the like. Perform (Steps 122 to 12)
6). Here, if Sugire corrected current position is the node N _1,
The front node of the existing link is the node N ₂ , and the rear node is the node N ₁ . Then, moving to the flow of FIG. 6, the collating unit 19 determines again whether the vehicle is on the guidance route (step 201). When it is determined to be YES, the traveling direction of the intersection has already been provided (step 202).
Is YES), the intersection guidance control unit 24 does not output the extraction command. At this time, the passage determination unit 23 determines whether the backward node N ₁ detected this time by the existence link detection unit 13 matches the intersection node N ₃ previously extracted by the extraction unit 20.
Alternatively, the node N in the node row of the guidance route memory 18
₄ by determining whether there is a match since, determines whether passing through the intersection CP ₁ (step 208). Here since NO is subsequently distance calculator 22 based on the forward nodes enter corrected current position data newly input from the current position correction unit 12 from the existing link detecting unit 13, calculates the distance to the intersection CP ₁ (Step 209).
Here, it is assumed that it is 98 m.

Next, based on the distance information (98 m) newly input from the distance calculation unit 22, the intersection guidance control unit 24 rewrites the approach distance character drawn to the intersection drawn in the second V-RAM 26 to "98 m remaining" ( Step 21
0). As a result, the character of the approach distance to the intersection on the screen changes to "98 m remaining", and the driver should turn left at the intersection CP _1.
The distance to can be confirmed in real time.

[0042] Then, the intersection guidance control unit 24, the distance to the intersection CP ₁ has passed the point of 100m, and outputs a predetermined audio output command to the speech synthesis unit 29, "100m
Turn left first. "
0 (steps 211 and 212). The amplifier 30 to which the audio signal is input is amplified and then output to the speaker 31 for sound conversion. As a result, the driver can listen to the intersection traveling direction guidance voice, and even if he does not look at the screen,
m destination of intersection CP ₁ it can be seen that it is sufficient to turn left.

After performing the processing in step 212, the navigation controller 10 returns to step 121 in FIG. 5 and inputs the next current position data from the vehicle position calculation CPU 5 to correct the current position and to change the map according to the change in the current position. Of the vehicle, rewriting of the vehicle position mark and the emphasis guidance route, detection of an existing link, and the like (steps 122 to 126).
Then, the flow moves to the flow in FIG. 6. If the vehicle is on the guidance route (determination of YES in step 201), the vehicle is in the traveling direction guidance of the intersection, so it is determined that the vehicle has passed the intersection (steps 202 and 208), and the vehicle still passes if not, to calculate the distance from the vehicle position to the intersection CP ₁ (step 20
9) For example, if the distance is 90 m, the approach distance character in the intersection traveling direction guide image on the screen is changed to "90 m remaining" (step 210). However, this time, from 98m to 90m
, The intersection guidance control unit 24 does not output the voice output command (NO in step 211).

[0044] In the following, in accordance with in the same way as the vehicle position in the running of the vehicle is approaching the intersection CP _1, will not change the approach distance characters in the intersection traveling direction guide image on the screen in real-time, middle, 50m to the intersection CP ₁ When the vehicle passes the point, a guidance voice of "Please turn left at a distance of 50 m" is output.

[0045] The intersection travel direction guidance by screen and voice, the driver can bend in a direction along the guidance route in exactly intersections CP _1.

When the vehicle turns at the intersection CP ₁ along the guidance route, the existence link detecting unit 13 performs step 1 in FIG.
At 26, the front node N ₄ and the rear node N ₃ are detected. Then, in step 208 of FIG.
Determines that because the rear node matches the intersection node N ₃ extracted by the extraction unit 20 previously, passed through the intersection.
In this case, intersection guidance control section 24 terminates the intersection running direction guidance display outputs a synthetic stop command to the combining unit 27 for the current crossing CP ₁ (step 213). The synthesizing unit 27 that has input the synthesizing stop instruction is in the first V-RAM 2
Only the map image read from 5 is output to the video converter 28. Therefore, the screen temporarily contains only the map image.

After outputting the synthesis stop command, the intersection guidance control unit 24 outputs a new extraction command to the extraction unit 20, and in the same manner as described above, the intersection extraction control unit 24 becomes closest to the vehicle in the vehicle traveling direction on the guidance route. relates is next intersection CP _2, performs display control and the intersection direction of travel voice guidance control of the predetermined intersection running direction guide image, that the vehicle performs a display stop control intersection travel direction guiding image was successfully passed the intersection CP ₂ In the following, the same process is repeated to the destination.

Therefore, the driver can easily travel along the guidance route by simply going straight or turning left or right at each intersection in accordance with the intersection driving direction guidance image and the intersection driving direction guidance voice on the screen.

For example, when passing through the intersection CP ₁ , an error occurs in the map matching by the current position correction unit 12, and the forward node detected by the existing link detection unit 13 changes from the intersection N ₃ to the node N ₅ . skipping, when the rear node flew from node N ₂ to the node N _4, simply, the rear node performs the intersection passage judgment alone or determination matches the intersection node N _3, it can not confirm the pass, the actual despite the vehicle is heading to CP ₂ passes through the intersection CP ₁ is in, the screen becomes a remains of intersection traveling direction guide image on the intersection CP _1, and was left in the driver the wrong intersection misunderstanding or, or it has become impossible to guide about the intersection CP _2. However, in this embodiment, the passage determination unit 23 determines in step 208 of FIG.
The backward node is an intersection node N ₃ previously extracted by the extraction unit 20 in the node sequence stored in the guidance route memory 18.
Since it is determined that also passes through the intersection CP ₁ if they match more 1 Tsuato node N ₄ subsequent nodes, exit the intersection traveling direction guidance regarding intersections CP ₁ of the screen, the intersection direction of travel about the next intersection CP ₂ Guidance can be started, and the situation that the guidance of the driving direction at the intersection does not occur does not occur, and the guidance of the driving direction at each intersection on the guidance route can be reliably provided. Driving along can be performed.

[0050] Further, in a state where the screen is an intersection running direction guide image regarding intersections CP ₁ is displayed, resulting in straight accidentally intersections CP ₁ to be left is the driver, is detected by the existing link detecting section 13 Since the forward node is the node N _b and the backward node is the node N ₃ , the matching unit 19
Determines that the vehicle has deviated from the guidance route in step 201 of FIG. At this time, since the intersection guidance control unit 24 has been displaying the intersection traveling direction proposal image, the intersection guidance control unit 24 gives the combining stop command to the combining unit 27 to erase the intersection traveling direction proposal image (steps 214 and 215). As a result, the driver knows that the vehicle has deviated from the guidance route, and can take appropriate measures such as a U-turn. Thereafter, when the vehicle returns to the guidance route, the intersection traveling direction guidance is resumed in the same manner as described above (steps 201 to 206). Therefore, the driver knows that the vehicle has returned to the guidance route and follows the guidance. For example, it is possible to go to the destination along the guidance route.

In the above-described embodiment, the traveling direction guidance sound is output by one speaker.
Two speakers are provided, and when guiding a left turn, a guidance sound is output from the left speaker, when guiding a right turn, a guidance sound is output from the right speaker, and when guiding straight ahead, guidance sounds are output from both the left and right speakers. You may do so.

Further, in the intersection traveling direction guidance image, either one of the traveling direction arrow pattern and the traveling direction character may be displayed, and further, the intersection traveling direction guidance image and the intersection traveling direction guidance voice may be displayed. Alternatively, guidance may be provided by only one of them.

The map matching by the current position correction unit is not limited to the projection method, and may be performed by another method such as pattern matching.

[0054]

As described above, according to the present invention, based on the vehicle position information, the guidance route is stored by referring to the node sequence of the guidance route storage means or the node sequence of the guidance route storage device and the map data of the map data storage device. The direction to travel at the intersection that is closest to the vehicle position when viewed in the vehicle traveling direction above is determined, and based on the determined traveling direction, a predetermined intersection traveling direction guidance is performed, and then based on the vehicle position information. , The node that the vehicle has passed last is detected, and the detected node matches the intersection in the intersection traveling direction guidance, or the node that is earlier on the guidance route than the intersection in the node row of the guidance route storage means. When this is the case, the current intersection driving direction guidance ends. With this, the driver can be guided in the direction to travel at the next intersection in the vehicle traveling direction on the guidance route, and when the vehicle passes the intersection, the vehicle position information jumps over the intersection and changes. Also, after completing the current intersection driving direction guidance, new driving direction guidance for the next intersection can be performed, so that the driving direction guidance for each intersection on the guidance route can be reliably executed, and the driver can It is possible to easily and surely know in which direction to travel at each intersection on the route.

[Brief description of the drawings]

FIG. 1 is a block diagram of a main part of an on-vehicle navigator embodying a route guidance method for an on-vehicle navigator according to the present invention.

FIG. 2 is an explanatory diagram showing a configuration of data stored in a guidance route memory of FIG. 1;

FIG. 3 is an explanatory diagram of departure place data and destination data stored in a guidance route memory of FIG. 1;

FIG. 4 is an explanatory diagram illustrating an operation of a traveling direction calculation unit in FIG. 1;

FIG. 5 is a flowchart showing an operation of the navigation controller of FIG. 1;

FIG. 6 is a flowchart showing an operation of the navigation controller of FIG. 1;

FIG. 7 is an explanatory diagram illustrating an intersection guidance operation by the navigation controller of FIG. 1;

FIG. 8 is an explanatory diagram showing a screen display example of the CRT display device of FIG. 1;

FIG. 9 is an explanatory diagram showing a configuration of road data in map data.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CD-ROM 3 Orientation sensor 4 Distance sensor 5 Vehicle position calculation CPU 6 CRT display device 10 Navigation controller 12 Current position correction unit 13 Existing link detection unit 15 Map image drawing control unit 17 Guidance route search unit 18 Guidance route memory 20 Extraction Unit 21 traveling direction calculation unit 24 intersection guidance control unit 26 second V-RAM 29 voice synthesis unit 30 amplifier 31 speaker

Continuation of front page (56) References JP-A-62-32600 (JP, A) JP-A-4-259814 (JP, A) JP-A-62-138719 (JP, A) JP-A-62-95699 (JP) JP-A-63-196813 (JP, A) JP-A-62-74199 (JP, A) JP-A-62-102112 (JP, A) JP-A-2-107018 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) G01C 21/00 G08G 1/0969 G09B 29/10

Claims (1)

(57) [Claims] 1. A map data storage means for storing map data, and guidance for obtaining a node sequence constituting an optimal guidance route from a departure place to a destination with reference to the map data stored in the map data storage means. Route search means, guidance route storage means for storing a node sequence constituting the guidance route determined by the guidance route search means, and vehicle position detection means for detecting the current position of the vehicle, which are stored in the map data storage means. Route guidance of an in-vehicle navigator that displays a map image around the vehicle position together with the vehicle position mark on the display means using the map data obtained and provides a predetermined route guidance using the node sequence stored in the guidance route storage means. The method, comprising: a node sequence of a guidance route storage means based on vehicle position information;
Alternatively, by referring to the node sequence of the guidance route storage means and the map data of the map data storage means, the direction to travel at the intersection closest to the vehicle position when viewed in the vehicle traveling direction on the guidance route is determined. Based on the obtained driving direction, after providing a predetermined intersection driving direction guidance, based on the vehicle position information, detect the node that the vehicle last passed, and match the detected node with the intersection in the intersection driving direction guidance Or the current intersection traveling direction guidance is terminated when a node that is earlier on the guidance route than the relevant intersection in the node row of the guidance route storage means is provided. How to guide.