JP2002296065A - Navigation device and program for road guiding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inform a driver without imparting feeling of wrongness of a spot to which attention is to be aroused. SOLUTION: This device has a present place detection means for detecting the present place, a road state information acquiring processing means 91 for acquiring road state information, a determination processing means of a road to be followed 92 for determining a road to be followed relative to prescribed crossings in the range from the present place to the spot to which attention is to be aroused based on the road state information, an attention arousing level setting processing means 93 for setting an attention arousing level based on the form of each road to be followed, and an attention arousing processing means 94 for executing attention arousing by a guiding method corresponding to the attention arousing level. In this case, determination of the roads to be followed is executed relative to the prescribed crossings in the range from the present place to the spot to which attention is to be aroused, and the attention arousing level is set based on the form of each road to be followed, and attention arousing is executed by the guiding method corresponding to the attention arousing level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation device and a program for a road guidance method.

[0002]

2. Description of the Related Art Conventionally, in a navigation device,
The current location of the vehicle by the current location detection means,
The current location is detected, and the direction of the vehicle,
The own vehicle direction is detected, and based on the map data read from the data recording unit, a map screen is set on the display of the display unit, and the current location, the own vehicle direction, and a map of the surrounding area are displayed on the map screen. It has become. The navigation device is used as a route search device, and when an operator, for example, a driver operates an input unit to input a destination, a route search process is performed, and a route from the current location to the destination is determined. The searched route, that is, the searched route, that is, the searched route is displayed and guided on the map screen. Therefore, the driver can drive the vehicle according to the map or the searched route.

[0003] By the way, when the search route is not guided or when the vehicle is traveling outside the search route, a point to call attention such as a sharp curve in the direction of the road, that is, a point to call attention is called. In some cases, a navigation device has been provided that notifies the driver of the fact (see Japanese Patent Application Laid-Open No. 2000-18959).

[0004]

However, in the conventional navigation apparatus, the direction of the road is determined uniformly, and the fact that there is an alert point is uniformly reported. If the driver does not travel on the road, the driver may feel uncomfortable with the notification.

[0005] The present invention solves the above-mentioned problems of the conventional navigation device, and provides a navigation device and a road guidance method capable of notifying a driver of a point to call attention without giving a sense of incongruity. The purpose is to provide the program.

[0006]

For this purpose, in the navigation device according to the present invention, a current position detecting means for detecting a current position, a road condition information acquisition processing means for acquiring road condition information, and a navigation device based on the road condition information. , For a given intersection from your current location to a point to alert you,
Road-road determination processing means for determining a road-road, alert level setting processing means for setting an alert level based on the form of each road-road, and alerting by a guidance method corresponding to the alert level. Alert processing means for performing the following.

In another navigation device of the present invention, the alert processing means determines a guidance method based on the lowest alert level among alert levels for each intersection.

In still another navigation device according to the present invention, the alert processing means executes the alert when the vehicle reaches an alert execution point set before the alert point.

In still another navigation device of the present invention, the alert level setting processing means further comprises:
The alert level is set when the vehicle reaches the alert information creation point.

[0010] In the program of the road guidance method of the present invention, the computer is provided with a road condition information acquisition processing means for acquiring road condition information, based on the road condition information, a predetermined distance from a current position to a point to be alerted. For the intersection, road-road determination processing means for determining a road-road, an alert level setting processing means for setting an alert level based on the form of each road-road, and a guidance method corresponding to the alert level. It is made to function as alerting processing means for executing alerting.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a functional block diagram of a navigation device according to an embodiment of the present invention.

In the figure, reference numeral 21 denotes a GPS as a current position detecting means for detecting a current position; 91, a road condition information obtaining means for obtaining road condition information; 92, a warning is issued from the current position based on the road condition information. A road-road determination process means for determining a road-road for a predetermined intersection to a power point, a warning level setting processing means 93 for setting a warning level based on the form of each road-road, a 94 This is an alert processing means for executing alert by a guidance method corresponding to the alert level.

FIG. 2 is a block diagram of the navigation device according to the embodiment of the present invention.

In FIG. 1, reference numeral 14 denotes a navigation device. The navigation device 14 includes a current position detection processing unit 15 for detecting a current position, a data recording unit 16 as a recording medium on which road data and the like are recorded, and a computer. A navigation processing unit 17, an input unit 34, a display unit 35, a voice input unit 36, and a voice output unit that function as various processing units and perform various arithmetic processing such as navigation processing based on input information. 37 and communication unit 3
A vehicle speed sensor 41 is connected to the navigation processing unit 17.

The current position detection processing unit 15
GPS21, geomagnetic sensor 2 as current location detecting means
2. It comprises a distance sensor 23, a steering sensor 24, a beacon sensor 25, a gyro sensor 26, an altimeter not shown, and the like.

The GPS 21 detects a current position on the earth by receiving a radio wave generated by an artificial satellite, the geomagnetic sensor 22 detects an azimuth of the vehicle by measuring geomagnetism, and 23 detects the distance between predetermined positions on the road and the like. Examples of the distance sensor 23 include a sensor that measures a rotation speed of a wheel (not shown) and detects a distance based on the rotation speed, a sensor that measures an acceleration, and detects a distance by integrating the acceleration twice. Can be used.

The steering sensor 24 detects a rudder angle.
For example, an optical rotation sensor, a rotation resistance sensor attached to a rotating portion of a steering wheel (not shown),
An angle sensor or the like attached to a wheel is used.

The beacon sensor 25 receives position information from a radio beacon, an optical beacon or the like disposed along the road to detect the current location. The gyro sensor 26 detects a rotational angular velocity of the vehicle, that is, a turning angle. As the gyro sensor 26, for example, a gas rate gyro, a vibration gyro, or the like is used. Then, by integrating the turning angle detected by the gyro sensor 26, the azimuth of the own vehicle can be detected.

The GPS 21 and the beacon sensor 25 can independently detect the current location.
The current position can also be detected by combining the distance detected by the distance sensor 23 with the vehicle direction detected by the geomagnetic sensor 22 or the turning angle detected by the gyro sensor 26. Also,
The current position can also be detected by combining the distance detected by the distance sensor 23 and the steering angle detected by the steering sensor 24.

The data recording unit 16 stores a map data file, an intersection data file, a node data file,
A database including a road data file, a photograph data file, and a facility information data file in which facility information such as hotels, gas stations, parking lots, and tourist spot information in each region are recorded. In addition, in each of the data files, in addition to data for searching for a route, a guide map is displayed along a searched route on a screen set on a display of the display unit 35, and a characteristic at an intersection or a route is displayed. Various kinds of data are recorded for displaying various pictures, frame diagrams, etc., displaying the distance to the next intersection, the traveling direction at the next intersection, and displaying other guidance information. The data recording unit 16 also records various data for outputting predetermined information by the audio output unit 37.

The intersection data file records intersection data relating to each intersection, the node data file records node data relating to node points, and the road data file records road data relating to roads. And road condition data as road condition information representing a road condition is constituted by the road data. The node data constitutes at least the position and shape of a road in the map data recorded in the map data file, and includes actual branch points (including intersections, T-shaped roads, etc.) and node points. And data indicating a link between the node points connecting the respective node points.

According to the road data, the width of the road itself, the gradient, the cant, the bank,
The condition of the road surface, the number of lanes on the road, the point where the number of lanes decreases, the point where the width decreases, etc.
Intersections, T-shaped roads, corner entrances, etc., road attributes are downhill roads, uphill roads, etc., and road types are national roads, general roads, expressways, etc. Furthermore, according to road data, railroad crossings, highway exit rampways,
Highway toll gates are also constructed.

The navigation processing unit 17
CPU 3 for controlling the entire navigation device 14
1. In addition to the RAM 32 used as a working memory and a control program when the CPU 31 performs various arithmetic processes, the CPU 31 searches for a route to a destination, guides traveling on the route, and determines a specific section. The ROM 33 as a recording medium on which the various programs are recorded. The input unit 34, the display unit 35, the audio input unit 36, the audio output unit 37, and the communication unit 38 are connected to the navigation processing unit 17. .

The data recording unit 16 and the ROM 3
Reference numeral 3 includes a magnetic core (not shown), a semiconductor memory, and the like. The data recording unit 16 and the ROM 3
3, magnetic tape, magnetic disk, floppy (registered trademark) disk, magnetic drum, CD, MD, DVD,
Various recording media such as optical disks, MOs, IC cards, and optical cards can also be used.

In this embodiment, the ROM 33
Various programs are recorded in the data recording unit 16.
Although various types of data are recorded on the external storage medium, programs, data, and the like can be recorded on the same external recording medium. In this case, for example, a flash memory (not shown) can be provided in the navigation processing unit 17, and the program, data, and the like can be read from the external recording medium and written to the flash memory. Therefore, the program, data, and the like can be updated by exchanging an external recording medium. Further, a control program or the like of the automatic transmission control device (not shown) can be recorded on the external recording medium. In this way, the programs recorded on various recording media are started,
Various processes can be performed based on the data.

The communication section 38 is for transmitting and receiving various programs, data, and the like to and from an FM multiplex transmission apparatus, a telephone line, a communication line, and the like. In addition to traffic information including traffic congestion information, regulation information, parking lot information, and the like, received by a receiving device such as a GPS receiver, various data such as traffic accident information and D-GPS information for detecting a GPS 21 detection error are received. I do.

Further, a program for realizing the functions of the present invention, other programs for operating the navigation device 14, data, and the like are transmitted from an information center (an Internet server, a navigation server, etc.) to a plurality of base stations (such as a server for navigation). It can also be transmitted to an Internet provider terminal, a communication station or the like connected to the communication unit 38 via a telephone line, a communication line, or the like), and from each base station to the communication unit 38. In that case, when at least a part of the program and data transmitted from each base station is received, the CPU 31 downloads to a recording medium such as a readable / writable memory, for example, a RAM 32, a flash memory, and a hard disk, By starting the program, various processes can be performed based on the data.
It should be noted that the program and the data can be recorded on different recording media, or can be recorded on the same recording medium.

Also, using a personal computer for home use, the program, data, etc. transmitted from the information center are downloaded to a recording medium such as a memory stick or a floppy disk which is detachable from the personal computer, and the program is started. Various processes can be performed based on the data.

The input unit 34 is used to correct the current position at the start of traveling and to input a destination. Operation keys displayed as images on a screen set on the display are provided. It consists of operation switches such as an operation menu. Therefore, input can be performed by pressing (touching) the operation switch. In addition, as the input unit 34, a keyboard, a mouse, a barcode reader, a light pen, a remote control device for remote operation, and the like, which are provided separately from the display unit 35, can be used.

On the screen set on the display, operation guidance, an operation menu, operation key guidance, a route from the current location to the destination, guidance information along the route, and the like are displayed. As the display unit 35, a display such as a CRT display, a liquid crystal display, and a plasma display can be used. In addition, a hologram device that projects a hologram on a windshield can be used.

The voice input unit 36 is constituted by a microphone (not shown) or the like, and can input necessary information by voice. Further, the audio output unit 37
Includes a voice synthesizer and a speaker (not shown), and outputs sound information, for example, guide information and speed change information composed of voice synthesized by the voice synthesizer from the speaker.
In addition to the speech synthesized by the speech synthesizer,
Various sounds, various kinds of guidance information recorded in advance on a tape, a memory, or the like can be output from a speaker.

Next, the navigation device 14 having the above-described configuration is used.
Will be described.

First, when the input unit 34 is operated by the driver and the navigation device 14 is activated, the CPU 3
The navigation initialization processing means (not shown) performs navigation initialization processing, and in the navigation initialization processing, the initialization processing means of the navigation initialization processing means performs initialization processing for determining the own vehicle direction.

Subsequently, a matching processing means (not shown) of the CPU 31 performs matching processing to read out matching data such as the current position, own vehicle direction, node data, map data, and the like. The determination processing means performs the own vehicle direction determination processing. For this purpose, the vehicle direction detecting means (not shown) of the CPU 31 integrates the turning angle detected by the gyro sensor 26 and detects the vehicle direction. In the present embodiment, the matching processing unit reads node data, map data, and the like from the data recording unit 16, but can also read the data via the communication unit 38.

Next, display processing means (not shown) of the CPU 31 sets a map screen on the display by performing display processing, displays a peripheral map on the map screen in accordance with the map data, and performs detection. The determined current position and the determined own vehicle direction are displayed.

When the navigation device 14 is used as a route search device, when the driver operates the input unit 34 to input a destination, the CPU 31 operates.
The destination setting processing means (not shown) performs a destination setting process to set a destination. Further, a current location update processing unit (not shown) of the CPU 31 performs a current location update process,
Update the current location as the vehicle travels. Then, CPU
A route search processing unit 31 (not shown) performs a route search process to search for a route from the current location to the destination.

When the route is searched, the display processing means performs a display process, sets a map screen on the display, and displays the current location, the own vehicle direction, a map of the surrounding area, and a search route on the map screen. Display and guide. Therefore,
The driver can drive the vehicle according to the search guidance.

When the search route is not guided or when the vehicle is traveling outside the search route, the CP
The alerting point notification processing means (not shown) of U31 performs alerting point notification processing, notifies the driver that there is an alerting point, and alerts the driver. For this purpose, the traveling route prediction processing means of the alerting point notification processing means performs a traveling route prediction process to predict a route on which the vehicle travels.

Next, the operation of the traveling route prediction processing means will be described.

FIG. 3 is a flowchart showing the operation of the traveling route prediction processing means in the embodiment of the present invention.

First, the road condition information acquisition processing means 91 (FIG. 1) of the traveling route prediction processing means is connected to the data recording section 16.
The road data of the current location is read and obtained from (FIG. 2),
A predetermined intersection is recorded in the RAM 32 in the traveling direction from the current position based on the road data. In the present embodiment, each intersection is specified, and the intersection data for the next intersection is specified from the data recording unit 16. Is read and obtained, and recorded in the RAM 32. Note that the road condition information acquisition processing means 91 can also acquire road data and intersection data via the communication unit 38.

The intersection data includes data such as the number of the intersection, whether there is a signal at the intersection, the number of roads connected to the intersection, that is, the number of connecting roads, the angle between the roads, and the like. For each road, it is connected to the road number, road type, width, whether or not the road is the target of route guidance, whether it is a narrow street that is not the target of route guidance (a road with a width of 3 m or less), facilities, etc. The data includes whether the road is an attachment road, whether there is a restriction such as no entry, and whether the road is a road on a database.
The intersection includes not only an intersection on an actual road but also a boundary point on a road between adjacent division regions when the road data is divided by a secondary mesh. Whether or not the road is a road on the database is determined by a field survey or the like.

The road-road determination processing means 92 of the traveling route prediction processing means performs road-road determination processing, and the alert level setting processing means 93 of the travel path prediction processing means executes the alert level setting processing. Then, it is determined whether the first to fourth prediction conditions are satisfied for each intersection, and a road is determined based on the determination result. In addition, the alert levels LB0 to LB4 for the alert points are set based on the form of the road at each intersection, and the alert levels LB0 to LB4 are attached to the road at each intersection. Note that the alert levels LB0 to LB4 are recorded by being added to link data constituting road data for the roadside road.

For this purpose, the roadside road determination processing means 92 determines whether the first prediction condition is satisfied based on whether the number of connecting roads excluding the approach road at the next intersection is 1 or less. If the number of connecting roads is 1 or less and the first prediction condition is satisfied, the road-road determination processing means 92 determines the road on which the vehicle is traveling as a road-road, and sets the alert level setting processing. Means 93
Set the alert level LB to 0. In addition, the number of connecting roads is 1
If the first prediction condition is not satisfied, the road-road determination processing means 92 determines whether or not the number of roads targeted for route guidance, that is, whether the number of connection-target roads is equal to or less than one, is equal to or less than one. It is determined whether the prediction condition is satisfied.

Then, the road-road determination processing means 92 is executed.
When the number of connection roads to be guided is 1 or less and the second prediction condition is satisfied, the road to be route-guided is determined to be a road-like road, and the alert level setting processing means 93
Sets the alert level LB to 1. When the number of connected roads to be guided is greater than one and the second prediction condition is not satisfied, the road-road determination processing means 92 determines whether there is a road-road in the database among the roads connected to the intersection. Then, it is determined whether the third prediction condition is satisfied. In addition, there is a road on the database.
If the prediction condition is satisfied, the road determination processing means 9
No. 2 judges the road or road on the database as a road or road, and the alert level setting processing means 93 sets the alert level LB to 2. Then, when there is no road road on the database and the third prediction condition is not satisfied, the road road determination processing means 92 determines whether there is a road road determined by logic among the roads connected to the intersection. Then, it is determined whether the fourth prediction condition is satisfied.

The determination by the logic means that the road is estimated from the information such as the road type, the width, the presence or absence of the traffic light, the intersection, etc. (however, the road information on the database is excluded). It is.

In addition, the road-road determination processing means 92
If there is a road that is estimated by the logic and the fourth prediction condition is satisfied, the road or road estimated by the logic is determined as the road or road, and the alert level setting processing unit 93 performs The level LB is set to 3, and if there is no road estimated by the logic and the fourth prediction condition is not satisfied, the alert level LB is set to 4. The alert level LB is 0, 1, 2,
It is lowered in the order of 3, 4.

Subsequently, the not-shown road determination processing means of the traveling route prediction processing means performs a not-shown road determination process to determine each of the notable roads from the current position to the alerting point, and to determine each of the notable roads. A route composed of a set of roads is predicted as a traveling route in a road direction.

As described above, the roadside road determination processing means 92 determines whether or not the first to fourth prediction conditions are satisfied for each intersection from the current position to the alert point, and based on the determination result. Then, the alert level setting processing means 93 sets the alert levels LB0 to LB4. Then, it is determined whether there is an alerting point on the road, and if there is an alerting point, the data of the alerting point is added to the link data and recorded, and the process is terminated. If not, read the next intersection data. The travel route prediction processing is sequentially performed for each intersection within a predetermined range (for example, the length of the travel route in the road direction is 10 [km]). However, when there is no next intersection of the traveling route in the traveling direction, that is, when there is no traveling road, the prediction of the traveling route is terminated at that point.

The traveling route prediction processing is performed each time the vehicle travels a predetermined distance and every time a predetermined time elapses. Therefore, when the vehicle does not enter the road determined as the road-by-road, the traveling route prediction processing is performed again based on the updated current location.

The roads on the database and the roads determined by the logic are roads for which it is determined that driving guidance is unnecessary in view of the normal driving mode of the vehicle. Point),
If the angle between the approach road and the exit road is close to 180 [°], the exit road is a road-side road. Also,
Not only the angle but also the road type and the like are considered. For example, at an intersection where a prefectural road with a small width is connected to a national road with a large width, the national road is curved, and the prefectural road is connected to a portion where the curve starts to be curved, and from the current traveling direction of the vehicle, a person entering the prefectural road Even if the road is almost straight ahead, the national road becomes a road.

Next, the flowchart will be described. Step S1 The road data at the current location is read. Step S2: Read the next intersection data. Step S3: Determine whether there is a next intersection.
If there is a next intersection, the process goes to step S4. If there is no next intersection, the process ends. Step S4: It is determined whether or not the number of connecting roads is one or less. If the number of connecting roads is 1 or less, step S5
On the other hand, if the number of connecting roads is more than 1, the process proceeds to step S6. Step S5: The alert level LB is set to 0. Step S6: It is determined whether or not the number of connection roads to be guided is 1 or less. If the number of guidance target connection roads is one or less, the process proceeds to step S7, and if the number of guidance target connection roads is more than one, the process proceeds to step S8. Step S7: The alert level LB is set to 1. Step S8: It is determined whether or not there is a road on the database among the roads connected to the intersection. If there is a road on the database, go to step S9.
If there is no road, the process proceeds to step S10. Step S9: Set 2 to the alert level LB. Step S10: It is determined whether or not there is a road that is determined by the logic among the roads connected to the intersection. If there is a road determined by the logic, the process proceeds to step S11. If there is no road, the process proceeds to step S12. Step S11: 3 is set to the alert level LB. Step S12: The alert level LB is set to 4. Step S13: A road determination process is performed. Step S14: It is determined whether or not there is an alert point on the determined road. If there is an alerting point on the determined road, the process ends, and if there is no alerting point, the process returns to step S2.

Subsequently, the alerting means 9 of the CPU 31
No. 4 performs alerting and alerts the driver.

Next, the operation of the alert processing means will be described.

FIG. 4 is a main flow chart showing the operation of the alert processing means in the embodiment of the present invention, FIG. 5 is a diagram showing a subroutine of a current alert level determining process in the embodiment of the present invention, and FIG. It is a figure explaining the alerting method in an embodiment of the invention.

In this case, on the traveling route, a point at which the alert is executed a predetermined distance from the alert point, for example, 200 [m] before, that is, an alert execution point is set. Then, the alert processing means 94 (FIG. 1) determines whether the vehicle has reached the alert execution point. Therefore, the alert level setting processing means 93 determines that the vehicle has reached the alert execution point when the coordinates of the current location match the coordinates of the alert execution point. Then, when the vehicle passes the alert execution point, the current alert level determination processing means (not shown) of the alert processing means 94 performs the current alert level determination process, and alerts the alert location at the current location. Location alert level LB for
Determine m.

For this purpose, the current location alert level determination processing means first initializes comparison data serving as a reference value for determining the current location alert level LBm, and determines whether the alert level is equal to or greater than the comparison data. Judge whether or not. If the alert level is lower than the comparison data, the alert level is set in the comparison data.

The present location alert level determination processing means reads out the link data of each of the roads,
It is determined whether or not the data of the alerting point is added to the link data. If the data of the alerting point is added to the link data, the alerting level LB0 for the road from the current location to the alerting point is determined. LB4
The determination of is ended. In this way, the lowest alert level among the alert levels LB0 to LB4 is determined as the current location alert level LBm.

When the current location alert level LBm is determined, the alert processing means 94 executes alerting by a guidance method corresponding to the current location alert level LBm shown in FIG. In FIG. 6, a first symbol in which a black circle is drawn in a solid rectangle, a second symbol in which a black circle is drawn in a dashed rectangle, and a first symbol in which a dashed white circle is drawn in a dashed rectangle. Although the symbol of 3 is shown,
The degree of alerting is changed by displaying the third symbol on the map screen, and the first symbol has a strong alerting degree following the voice guidance, and the second and third symbols are alerted in order. The degree of is weakened. In addition, ○ indicates that the alert is performed, and X indicates that the alert is not performed.

Then, the alert processing means 94 determines whether or not the current location alert level LBm is 0. If the current alert level LBm is 0, as shown in FIG. The voice guidance by the unit 37 (FIG. 2) is performed, and the first symbol is displayed on a map screen of a display (not shown) of the display unit 35. When the current location alert level LBm is 1, the first symbol is displayed on the map screen. 1 is displayed and the current location alert level LBm is 2
, A second symbol is displayed on the map screen, and if the current location alert level LBm is 3, a third symbol is displayed on the map screen, and the current location alert level LBm is displayed.
If m is 4, no alert is issued. In this manner, the alert point is notified each time the vehicle passes through each intersection until the alert point is reached.

As described above, every time the vehicle passes through each intersection,
Since the degree of alerting can be changed based on the alerting level set in accordance with the determination of the road, the alerting point can be notified to the driver without giving a sense of incongruity.

Further, since the alert is performed only when the vehicle is approaching the alerting point, that is, when the vehicle has reached the alerting execution point, the alerting point which is far away from the current location is not alerted. Do not alert. Therefore, the driver does not feel troublesome to call attention.

Next, the flowchart of FIG. 4 will be described. Step S21: It is determined whether or not the alert execution point has been reached. If it has reached the alert execution point, the process proceeds to step S22, and if it has not reached, the process ends. Step S22 The present location alert level determination process is performed. Step S23: A warning is issued using a guidance method corresponding to the current location warning level. Step S24: It is determined whether or not the vehicle has passed the intersection. If the vehicle has passed the intersection, the process proceeds to step S25. If the vehicle has not passed, the process returns to step S23. Step S25: It is determined whether or not the alert point has been reached. If you reach the alert point, end the process,
If not, the process returns to step S22.

Next, the flowchart of FIG. 5 will be described. Step S12-1: Initialize the comparison data. Step S12-2: It is determined whether or not the alert level is equal to or higher than the comparison data. If the alert level is equal to or higher than the comparison data, the process proceeds to step S12-4. If the alert level is lower than the comparison data, the process proceeds to step S12.
Go to -3. Step S12-3: An alert level is set in the comparison data. Step S12-4: Read the next link data. Step S12-5: It is determined whether or not the data of the alert point is added to the link data. If the alert data is added to the link data, the process proceeds to step S12-6; otherwise, the process returns to step S12-2. Step S12-6: The lowest alert level is determined as the current alert level LBm, and the process ends.

Next, an example showing the guidance method will be described.

FIG. 7 is a diagram showing an example of a road according to the embodiment of the present invention, FIG. 8 is a diagram showing a first example of an alerting method according to the embodiment of the present invention, and FIG. FIG. 10 is a diagram showing a second example of the alerting method in the embodiment, FIG. 10 is a diagram showing a third example of the alerting method in the embodiment of the present invention, and FIG. 11 is a diagram of the alerting method in the embodiment of the present invention. FIG. 12 is a diagram showing a fourth example, FIG. 12 is a diagram showing a fifth example of the alerting method in the embodiment of the present invention, and FIG. 13 is a sixth example of the alerting method in the embodiment of the present invention. FIG.

In FIG. 7, SN is the current location, a is a railroad crossing as an alert point, and b is a road r for which route guidance is to be performed.
1, and roads (narrow streets) r2 not subject to route guidance
Are connected, c is an intersection connected to a road r3 as a road on the database, d is an intersection connected to a road r4 as a road determined by logic, and e is a road on the database. And the intersection where the road as the road determined by the logic determination is not connected, and f is a point to call attention (set at a predetermined distance from the attention point, for example, 200 [m] in front). is there.

In this case, in the section AR1 from the point f to the intersection e, since the road at the intersection e is not set, the current location alert level LBm is 4. Therefore, no voice guidance is performed, and as shown in FIG. 8, a symbol for alerting is not displayed on the map screen.

A section A from the intersection e to the intersection d
In R2, since the road r4 at the intersection d is set as a road by logic determination, the current location alert level LBm becomes 3. Therefore, no voice guidance is performed, and a third symbol m3 for alerting is displayed on the map screen as shown in FIG.

In the section AR3 from the intersection d to the intersection c, since the road r3 at the intersection c is set as a road in the database, the current location alert level LBm becomes 2. Therefore, no voice guidance is performed, and a second symbol m2 for alerting is displayed on the map screen as shown in FIG.

A section A from the intersection c to the intersection b
At R4, since the road r1 is subject to route guidance at the intersection b and the road r2 is not subject to route guidance, the current location alert level LBm becomes 1. Therefore, no voice guidance is performed, and as shown in FIG. 11, the first symbol m for alerting is displayed on the map screen.
1 is displayed.

Section A from intersection b to level crossing a
At R5, there is no intersection and the number of connecting roads is 0, so the current location alert level LBm becomes 0. Therefore, voice guidance is performed, and as shown in FIG.
A message such as "There is a crossing ahead of XXm" is sent to the driver, and a first symbol m1 for alerting is displayed on the map screen. In the section AR5, the voice guidance is performed only once, and thereafter, as shown in FIG. 13, the first symbol m for alerting is displayed on the map screen.
1 is displayed.

By the way, in the above embodiment, the alert level setting processing means 92 judges the road on each intersection from the current position to the alert point, and sets the alert levels LB0 to LB4. Since the alert levels LB0 to LB4 are added to the link data constituting the road data of each road, it is necessary to increase the recording capacity of the RAM 32 in which the road data is recorded. Therefore, another embodiment of the present invention in which the recording capacity of the RAM 32 can be reduced will be described.

In this case, a road is determined for each intersection from the current location to the alert point, but the alert levels LB0 to LB4 are not set. Then, a point at which the setting of the alert level is started a predetermined distance, for example, 200 [m] before the alert execution point, that is, an alert information creation point is set.

When the vehicle arrives at the alert information creation point, the alert level setting processing means (not shown) of the travel path prediction processing means sets the alert level LB0 for each intersection from the alert information creation point to the alert information point. LB
4 is set. Therefore, the alert level setting processing means determines that the vehicle has reached the alert information creation point when the coordinates of the current location match the coordinates of the alert information creation point.

When the vehicle arrives at the alert execution point, the current alert level determination processing means determines the current alert level Lm.

As described above, the alert levels LB0 to LB4 are set after the vehicle arrives at the alert information creation point. Therefore, in the RAM 32, the alert levels LB0 to LB4 are stored in the link data. Can be reduced in recording capacity to be added to.
Therefore, the cost of the navigation device 14 can be reduced.

The present invention is not limited to the above-described embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0080]

As described above in detail, according to the present invention, in the navigation device, the current position detecting means for detecting the current position, the road condition information obtaining means for obtaining road condition information, Based on the information, for a predetermined intersection from the current location to a point to be alerted, a road-and-road determination processing means for determining a road-and-road, and an alert level are set based on the form of each road and road. There is an alert level setting processing means, and an alert processing means for executing alert by a guidance method corresponding to the alert level.

In this case, a road-road determination is performed for a predetermined intersection from the current location to a point to be alerted, and an alert level is set based on the form of each road, and the alert level is set. The alert is executed by the corresponding guidance method.

Therefore, it is possible to notify the driver of a point to be alerted without giving a sense of incongruity.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a navigation device according to an embodiment of the present invention.

FIG. 2 is a block diagram of the navigation device according to the embodiment of the present invention.

FIG. 3 is a flowchart illustrating an operation of a traveling route prediction processing unit according to the embodiment of the present invention.

FIG. 4 is a main flowchart showing the operation of the alert processing means in the embodiment of the present invention.

FIG. 5 is a diagram illustrating a subroutine of a current location alert level determination process according to the embodiment of the present invention.

FIG. 6 is a diagram illustrating a warning method in the embodiment of the present invention.

FIG. 7 is a diagram illustrating an example of a road according to the embodiment of the present invention.

FIG. 8 is a diagram showing a first example of an alerting method according to the embodiment of the present invention.

FIG. 9 is a diagram showing a second example of the alerting method in the embodiment of the present invention.

FIG. 10 is a diagram illustrating a third example of the alerting method in the embodiment of the present invention.

FIG. 11 is a diagram illustrating a fourth example of the alerting method in the embodiment of the present invention.

FIG. 12 is a diagram illustrating a fifth example of the alerting method in the embodiment of the present invention.

FIG. 13 is a diagram illustrating a sixth example of the alerting method in the embodiment of the present invention.

[Explanation of symbols]

 14 Navigation Device 17 Navigation Processing Unit 21 GPS 91 Road Condition Information Acquisition Processing Unit 92 Roadside Road Judgment Processing Unit 93 Warning Level Setting Processing Unit 94 Warning Warning Processing Unit a Railroad Crossing bee Intersection SN Current Location

Continued on front page F term (reference) 2F029 AA02 AB01 AB07 AC02 AC09 AC14 AC18 5H180 AA01 BB05 BB12 BB13 CC02 CC12 FF04 FF05 FF13 FF22 FF24 FF25 FF27 FF33 FF38

Claims (5)

[Claims] 1. A current position detecting means for detecting a current position; a road condition information obtaining processing means for obtaining road condition information; and a predetermined intersection from a current position to a point to be alerted based on the road condition information. Road-road determination processing means for determining a road-road, a warning-level setting processing means for setting a warning level based on the form of each road-road, and a guidance method corresponding to the warning level. A warning processing means for executing a warning. 2. The navigation device according to claim 1, wherein the alert processing means determines the guidance method based on the lowest alert level of the alert levels for each intersection. 3. The navigation device according to claim 1, wherein the alert processing means executes the alert when the vehicle reaches an alert execution point set before the alert point. 4. The navigation device according to claim 1, wherein the alert level setting processing means sets an alert level when the vehicle reaches an alert information creation point. 5. A road condition information acquisition processing means for acquiring road condition information, wherein the computer determines a road on a predetermined intersection from a current position to a point to be alerted based on the road condition information. Roadside road determination processing means to be performed, a warning level setting processing means for setting a warning level based on the form of each roadside road, and a warning processing means for executing a warning by a guidance method corresponding to the warning level A program for a road guidance method characterized by functioning as a.