JP4875509B2 - Navigation device and navigation method - Google Patents

Description

  The present invention searches for a guidance route from a departure point to a destination, acquires a vehicle position (vehicle position information) as the vehicle travels, and searches for a searched guidance route and the acquired vehicle. The present invention relates to a navigation device that executes a predetermined guidance process based on a relationship with a vehicle position and a navigation method used by the device.

As this type of guidance processing, for example, when the vehicle position deviates from the guidance route, a technique (reroute guidance) that searches again for a new guidance route from the current vehicle position to the destination and continues guidance. Technology that starts the guidance according to the guidance route when the vehicle first moves from the narrow street deviating from the guidance route to the guidance route and then gets on the guidance route. If you are going to follow the guidance route, for example, if you need to turn left and come close to an intersection that needs guidance, you can zoom in on the map near the intersection you are about to enter (an example of a detailed display) In addition, there is a display that overlaps the guidance route on this enlarged display screen and erases the enlarged display when exiting from an intersection (referred to as an enlarged display stop process).
In these guidance processes, a specific guidance process is required when a certain requirement is satisfied in the relationship between the current vehicle position and the guidance route.
Regarding the above reroute guidance processing, there is a technique disclosed in Patent Document 1 as a conventional technique, and there is a technique disclosed in Patent Document 2 regarding the above enlarged display.

  In these patent documents, the vehicle position is information obtained from GPS (Global Positioning System), and further, information obtained using autonomous navigation from information of travel direction and travel distance is used. Operation derived. The accuracy of the vehicle position obtained using these information at the present time is about several meters.

  On the other hand, with recent improvements in imaging devices and image recognition technology, image recognition devices that perform image recognition of features around the vehicle position using image information captured by a vehicle-mounted camera have been developed. (For example, Patent Document 3).

  Patent Document 3 discloses an image recognition device used for a vehicle-mounted navigation device. This image recognition apparatus acquires image information along a traveling road ahead of the vehicle imaged by an in-vehicle camera, and performs image recognition of features such as an intersection symbol based on the image information. Then, the navigation device detects the intersection based on the image recognition result, obtains the distance from the vehicle position to the intersection, and sets the vehicle position to a point on the road that is separated from the intersection position obtained from the map data by the distance. to correct. As a result, this navigation device can correct the vehicle position correctly even when map-matching to a position shifted forward and backward in the traveling direction when traveling on a characteristic road such as a long straight road. It has become.

  In this technique, since the vehicle position is obtained based on the features whose positions are known in advance, the vehicle position information with relatively high accuracy can be obtained.

Japanese Patent No. 3710654 Japanese Patent Laid-Open No. 08-278159 JP 09-243389 A

  However, the conventional techniques as disclosed in Patent Documents 1 and 2 have the following problems.

Problems in the reroute guidance process When performing a reroute, it is necessary to make sure that the position of the vehicle is out of the guidance route, and when trying to reroute accurately, the exact position of the vehicle is It is necessary to understand. However, in order to execute off-route and re-route using the own vehicle position information obtained based on autonomous navigation information including gyro information with relatively low accuracy, etc., the off-route determination is performed on the safe side. Therefore, a new route is searched from the low-accuracy vehicle position, and there is room for improvement in terms of accuracy of processing.

Problems in the enlarged display stop process For example, even if the enlarged display of this intersection is displayed at the left turn intersection, the guidance route is displayed on the enlarged display and the left turn is finished, the stop of the enlarged display is relatively Since the vehicle was stopped after traveling to a position some distance away from the intersection using low-accuracy vehicle position information, the stop of the enlarged display may deviate from the driver's sense, and the processing accuracy There was room for improvement.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a navigation device capable of adapting a guidance process to a driver's sense and accurately and accurately, and to be used in the device. It is to provide a navigation method.

In order to achieve the above-mentioned purpose, a route setting means for setting a guide route from information of a departure place and a destination is provided, and the relationship between the vehicle position information acquired by the vehicle position information acquisition means and the guide route based on the feature structure of the navigation apparatus for performing guidance in accordance with the prior SL guide route,
First vehicle position information acquisition means for acquiring first vehicle position information which is vehicle position information;
Second host vehicle position information acquisition means for acquiring second host vehicle position information which is host position information with higher accuracy than the first host vehicle position information ;
Based on the first vehicle position information and the second vehicle position information, vehicle position determination means for determining guided vehicle position information that is vehicle position information used for guidance ;
Guidance means for performing guidance based on the guidance route and the guidance vehicle position information ,
When it is determined that the state change of the guidance process is necessary, the guidance unit starts the state change when the accuracy of the guidance vehicle position information is equal to or higher than a preset reference accuracy,
When a change in the state of the guidance processing is determined to be necessary, when the accuracy of the guiding vehicle position information is lower than the reference accuracy, pending before Symbol status change, the guide itself during the pending The guidance process is started when the accuracy of the vehicle position information becomes higher than the reference accuracy.

A navigation device having this characteristic configuration
A route setting step for setting a guide route from information of a departure place and a destination, and a vehicle position acquisition step for obtaining own vehicle position information are executed, and based on the relationship between the own vehicle position information and the guide route, To execute guidance according to the guidance route,
A first own vehicle position information acquisition step of acquiring first own vehicle position information which is own vehicle position information;
A second host vehicle position information acquisition step for acquiring second host vehicle position information, which is host position information with higher accuracy than the first host vehicle position information ;
Based on the first vehicle position information and the second vehicle position information, a vehicle position determination step for determining guided vehicle position information that is vehicle position information used for guidance ;
Performing guidance based on the guidance route and the guidance vehicle position information ,
In the guidance process, when it is determined that the state change of the guidance process is necessary, if the accuracy of the guidance vehicle position information is equal to or higher than a preset reference accuracy, the state change is started.
When a change in the state of the guidance processing is determined to be necessary, when the accuracy of the guiding vehicle position information is lower than the reference accuracy, pending before Symbol status change, the guide itself during the pending The guidance process is started when the accuracy of the vehicle position information becomes higher than the reference accuracy.

The navigation apparatus according to the present application is provided with own vehicle position information acquisition means (first own vehicle position information acquisition means and second own vehicle position information acquisition means) that can obtain own vehicle position information with different accuracy. And the own vehicle position information acquired by both acquisition means has the accuracy of the second own vehicle position information higher than the accuracy of the first own vehicle position information.
The navigation device is configured to be able to execute various guidance processes (such as the reroute guidance process and the enlarged display stop process described above). (Referred to as position information) has at least different accuracy.

That is, the guidance vehicle position information is determined based on the first vehicle position information and the second vehicle position information, but the accuracy is relatively low in the case of the former information, and the accuracy in the latter case. It will be relatively expensive. Such a situation occurs because the vehicle position information is not always obtainable. Usually, when there is a possibility of obtaining at least two types of vehicle position information, the vehicle position information on the side with high accuracy that can be obtained at that time is determined as the guidance vehicle position information. Accordingly, the accuracy of the guidance vehicle position information changes every moment.
Therefore, in the navigation device, the accuracy of the guidance vehicle position information is a problem when a predetermined guidance process is started.
That is, when the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, the guidance state change based on the guidance vehicle position information is suspended (maintained as it is), and then higher than the reference accuracy. The guidance will be started when it becomes.
In this way, guidance is started for the first time in a state where the accuracy of the vehicle position information has become high (a state where the accurate vehicle position has been acquired), so the guidance process that matches well with the current traveling state is performed. Can be done. In addition, accurate guidance processing is possible.

Now, in the above-described navigation device,
A fixed factor error including an error included in the starting position, with the position indicated by the guidance own vehicle position information determined based on the second own vehicle position information as a starting position, and the first own vehicle position information An error including a distance factor error that increases in accordance with a moving distance from the starting position of the position indicated by the vehicle position information calculated based on the estimated vehicle position information as an estimation error. As a value that increases as the error value decreases, a confidence level determination unit that determines the confidence level of the guidance vehicle position information is provided,
The guide unit preferably uses the confidence level as the accuracy of the guidance vehicle position information .
The navigation device of this configuration is
In accordance with the vehicle position information based on the guided vehicle position information, a self-confidence level determining step for determining the confidence level of the guided vehicle position information is provided, and the accuracy of the vehicle position information can be represented by the determined confidence level.
By expressing the accuracy of the vehicle position information with an explicit index as the degree of confidence, and representing the accuracy of the vehicle position information with the degree of confidence, the state of the guidance processing based on the accuracy of the vehicle position information as in the present application Can be realized rationally and easily.

Now, the first vehicle position information acquisition means obtains the first vehicle position information based on one or both of GPS information obtained from the global positioning system and autonomous navigation information obtained by autonomous navigation,
It is preferable that the second vehicle position information acquisition unit obtains the second vehicle position information from feature information that is information related to the feature imaged by the imaging device.

By adopting this configuration, although the accuracy is relatively low, it is possible to obtain the first vehicle position information that can be acquired almost always at a high frequency. On the other hand, since the second vehicle position information is acquired based on the feature information of the feature existing along the traveling road, it is possible to obtain high information as the accuracy of the information although the acquisition frequency is relatively low. it can.
Therefore, the apparatus can be configured so that the guidance process can be started in a situation where the second host vehicle position information is used as the guidance host vehicle position information, and an accurate and accurate guidance process can be executed.

Further, the second vehicle position information acquisition unit may obtain the second vehicle position information from the position information obtained from the road traffic information communication system.
When the first vehicle position information is obtained based on one or both of the GPS information obtained from the global positioning system and the autonomous navigation information obtained by autonomous navigation, for example, if the lane is specified up to the traveling lane of the own vehicle Although the error may be large, the position information obtained from the road traffic information communication system can identify the traveling lane. Can be achieved.

Hereinafter, different guidance processes will be described.
1 Reroute guidance processing In the navigation device described so far,
It is provided with an off-route determination means for determining whether or not the vehicle position is out of the guide route,
In a state where the vehicle position is determined to be deviated from the guidance route by the route deviation determination means, a reroute process for newly setting a guidance route for reaching the destination from the vehicle position is configured to be executable.
A configuration is adopted in which when the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, the start of the reroute processing as the guidance processing is suspended and the reroute processing is started when the accuracy is higher than the reference accuracy. It is preferable.
The navigation device of this configuration is
Execute an off-route determination step for determining whether or not the vehicle position is off the guide route,
In order to execute a reroute process for newly setting a guide route for reaching the destination from the vehicle position in a state where it is determined that the vehicle position is out of the guide route,
When the accuracy of the guidance vehicle position information is lower than the reference accuracy set in advance, the start of the reroute processing as guidance is suspended, and then the reroute processing is started when the accuracy is higher than the reference accuracy.

  In this configuration, reroute processing is required when a route is deviated, but the position of the reroute processing is set to a position where the accuracy of the guidance vehicle position information is higher than the reference accuracy and the vehicle position is reliably grasped. (Reroute is not performed at the position of the vehicle with low accuracy and error), so that a reroute search with higher accuracy than before can be performed, and accurate and reliable guidance processing can be realized.

2 Line guidance processing In the navigation apparatus described so far,
Comprising a line judging means for judging whether or not the vehicle position is on the guide route;
It is configured to be able to start guidance according to the guidance route in a state in which the vehicle is determined to be on the guidance route by the lane determination means,
When the accuracy of the guidance vehicle position information is lower than the preset reference accuracy, the state change of guidance based on the guidance vehicle position information according to the guidance route as the guidance process is suspended and becomes higher than the reference accuracy In this case, it is preferable to adopt a configuration that starts guidance according to the guidance route.

The navigation device of this configuration is
In order to start guidance according to the guidance route in a state where it is determined that the own vehicle is on the guidance route by executing a lane determination step that determines whether or not the vehicle position is on the guidance route.
When the accuracy of the guidance vehicle position information is lower than the preset reference accuracy, the start of guidance based on the guidance vehicle position information according to the guidance route as the guidance is suspended, and then becomes higher than the reference accuracy In this case, guidance according to the guidance route is started.

  In this configuration, it is necessary to start the guidance according to the guidance route when the line is recognized, but the guidance start position is reliably determined so that the accuracy of the guidance vehicle position information is higher than the reference accuracy. Since the position is determined as a position (guidance is not started at the position of the vehicle with low accuracy and error), guidance according to the guidance route can be started in a more accurate state than before, and reliability can be improved. High guidance processing can be realized.

3 Enlargement display stop processing In the navigation apparatus described so far,
A detailed display necessary point judging means for determining whether or not there is a detailed display necessary point that requires detailed display on the guidance route is provided, and the detailed display necessary point is passed while the detailed display is being performed. It is configured to stop detail display,
Adopts a configuration that stops the detailed display as the guidance processing when the accuracy of the guidance vehicle position information is lower than the preset reference accuracy, and stops the detailed display when the accuracy is higher than the reference accuracy. It is preferable to do.

The navigation device of this configuration is
Perform the detailed display necessary point determination process to determine whether there is a detailed display necessary point that requires detailed display on the guidance route, and with the passing of the detailed display necessary point in the state of displaying the detail To stop displaying details,
When the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, the suspension of the detailed display as the guidance is suspended, and then the detail display is stopped when the accuracy is higher than the reference accuracy. Become.

  In this configuration, when the presence of a point requiring detailed display is recognized, it is necessary to execute the detailed display of the point and stop the detailed display as the point passes. Since the stop position is the position where the position of the vehicle is surely grasped with the accuracy of the guide vehicle position information being higher than the reference accuracy (detail display is not stopped at the position of the vehicle with low accuracy and error) The detailed display can be stopped at an accurate position where it is surely recognized that it is no longer needed, and an accurate guidance process can be realized.

  As such a point requiring detailed display, an intersection where a plurality of roads intersect or a branch point where roads branch are representative.

1. First Embodiment First, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a schematic configuration of a navigation device 1 according to the present embodiment. In the present embodiment, the navigation device 1 includes a first vehicle position information acquisition unit 2 for obtaining normal vehicle position information (hereinafter referred to as normal vehicle position information) with normal accuracy, and a high accuracy higher than the normal accuracy. A second vehicle position information acquisition unit 3 for obtaining accurate vehicle position information (hereinafter referred to as high-accuracy vehicle position information), and based on information on the higher accuracy between the vehicle position information The vehicle position determining unit 7 is configured to determine the vehicle position, and when the vehicle deviates from a previously obtained guide route (when the vehicle is off route), the second vehicle Only when the high-accuracy own vehicle position information is obtained by the position information acquisition unit 3 is the configuration in which reroute is applied.

  As shown in FIG. 1, each function unit of the navigation device 1, specifically, a first vehicle position information acquisition unit 2, a second vehicle position information acquisition unit 3, an image information acquisition unit 4, and an image recognition unit. 5, data extraction unit 6 (including target feature setting unit 6a), own vehicle position determination unit 7 (including confidence level determination unit 7a), and navigation calculation unit 8 (route setting unit 8a, off-route determination unit 8b, The rerouting determination / control unit 8c includes a processing unit such as a CPU as a core member, and a functional unit for performing various processes on input data is performed by hardware or software (program) or both. Implemented and configured.

  The map database 9 is a device having a recording medium capable of storing information and its driving means, such as a hard disk drive, a DVD drive equipped with a DVD-ROM, and a CD drive equipped with a CD-ROM. It is provided as a hardware configuration.

Hereinafter, the configuration of each part of the navigation device 1 according to the present embodiment will be described in detail.
1-1. Map Database The map database 9 is a database in which a plurality of map information M divided for each predetermined area and a plurality of feature information F associated with the map information are stored. FIG. 2 is an explanatory diagram showing an example of the configuration of the map information M and the feature information F stored in the map database 9. As shown in this figure, the map database 9 stores a road network layer m1, a road shape layer m2, and a feature layer m3.

  The road network layer m1 is a layer indicating connection information between roads. Specifically, it has information on a large number of nodes n having position information on a map expressed by latitude and longitude, and information on a large number of links k that form a road by connecting two nodes n. It is configured. Each link k has information such as road type (type of highway, toll road, national road, prefectural road, etc.) and link length as link information. The road shape layer m2 is a layer stored in association with the road network layer m1 and indicating the shape of the road. Specifically, information on a number of road shape complementary points s having position information on a map that is arranged between two nodes n (on link k) and expressed in latitude and longitude, and information on road width w Etc. are configured. The map information M is configured by the information stored in the road network layer m1 and the road shape layer m2.

  The feature layer m3 is configured in association with the road network layer m1 and the road shape layer m2, and is a layer in which information of various features provided on the road and around the road, that is, the feature information F is stored. is there. The feature in which the feature information F is stored in the feature layer m3 includes a road marking (paint marking) provided on the road surface. Examples of features related to such road markings include, for example, lane markings that divide lanes along the road (including various lane markings such as solid lines, broken lines, and double lines), and progressions that specify the traveling direction of each lane. Includes direction-specific traffic markings, pedestrian crossings, stop lines, speed indications, zebra zones, and more. In addition to such road markings, the features in which the feature information F is stored can include various features such as traffic lights, signs, overpasses, and tunnels.

  Further, the feature information F includes position information and form information of each feature as its contents. Here, the position information includes information on the position (latitude and longitude) of the representative point of each feature on the map and the direction of each feature. In this example, the representative point is set at the center in the length direction and the width direction of each feature. The form information includes information such as the shape, size, and color of each feature. In addition to these, the feature information F includes type information indicating the type of each feature. This type information specifically indicates road marking types such as “division lines (including line types such as solid lines, broken lines, and double lines)”, “traveling direction markings according to traveling direction”, and “pedestrian crossing”. Information.

1-2. First vehicle position information acquisition unit 2
The first vehicle position information acquisition unit 2 functions as first vehicle position information acquisition means for acquiring normal vehicle position information L1 indicating the vehicle position, that is, the current position of the vehicle. Here, the first vehicle position information acquisition unit 2 is connected to the GPS receiver 10, the direction sensor 11, and the distance sensor 12.

  The GPS receiver 10 is a device that receives GPS signals from a Global Positioning System (GPS) satellite. This GPS signal is normally received every second, and is output to the first vehicle position information acquisition unit 2. The first vehicle position information acquisition unit 2 receives a signal from a GPS satellite received by the GPS receiver 10. And information such as the current position (latitude and longitude), traveling direction, and moving speed of the host vehicle can be acquired.

  The direction sensor 11 is a sensor that detects the traveling direction of the host vehicle or a change in the traveling direction. The azimuth sensor 11 includes, for example, a gyro sensor, a geomagnetic sensor, an optical rotation sensor attached to a rotating part of a handle, a rotary resistance volume, an angle sensor attached to a wheel part, and the like. Then, the direction sensor 11 outputs the detection result to the first vehicle position information acquisition unit 2.

  The distance sensor 12 is a sensor that detects a vehicle speed and a moving distance of the host vehicle. The distance sensor 12 integrates, for example, a vehicle speed pulse sensor that outputs a pulse signal each time a drive shaft or wheel of the vehicle rotates a certain amount, a yaw / G sensor that detects the acceleration of the host vehicle, and the detected acceleration. It is composed of a circuit or the like. Then, the distance sensor 12 outputs information on the vehicle speed and moving distance as the detection result to the first vehicle position information acquisition unit 2.

The first vehicle position information acquisition unit 2 performs a calculation for identifying the vehicle position by a known method based on outputs from the GPS receiver 10, the direction sensor 11, and the distance sensor 12. Based on the outputs from the azimuth sensor 11 and the distance sensor 12, the position after moving from the position where the traveling is started by so-called autonomous navigation is specified. The first vehicle position information acquisition unit 2 acquires the map information M around the vehicle position extracted from the map database 9 by the data extraction unit 6, and performs known map matching based on the map information M, thereby acquiring the vehicle information. The position is corrected to be on the road indicated by the map information M. The information on the vehicle position acquired in this way is information including an error caused by the detection accuracy of each sensor 10-12.
And the first own vehicle position information acquisition part 2 is the normal own vehicle position information L1 which is the information of the present position of the own vehicle represented by the latitude and the longitude by the calculation result which specifies the said own vehicle position, the own vehicle Get information on the direction of travel. The normal vehicle position information L1 is output to the data extraction unit 6, the image recognition unit 5, the second vehicle position information acquisition unit 3, and the vehicle position determination unit 7.

1-3. Image Information Acquisition Unit The image information acquisition unit 4 acquires image information G around the vehicle position captured by the imaging device 13. Here, the imaging device 13 is a camera or the like provided with an imaging element, and is provided at a position where at least a road surface of a road around the own vehicle (own vehicle position) can be imaged. As such an imaging device 13, for example, a back camera or the like can be used as shown in FIG. Then, the image information acquisition unit 4 takes in analog imaging information captured by the imaging device 13 at a predetermined time interval, converts it into image information G of a digital signal, and acquires it. The time interval for capturing the image information G at this time can be set to, for example, about 10 to 50 ms. Thereby, the image information acquisition unit 4 can continuously acquire the image information G of a plurality of frames captured by the imaging device 13. The image information G acquired here is output to the image recognition unit 5.

1-4. Data Extraction Unit The data extraction unit 6 extracts the feature information F of the target feature ft to be subjected to image recognition processing from the map database 9. In this example, the data extraction unit 6 includes a target feature setting unit 6a, and the second vehicle position information acquisition unit 3 acquires a highly accurate position in the traveling direction of the normal vehicle position information L1 by the setting unit 6a. As shown in FIG. 3B, it is used for setting a target feature ft to be subjected to image recognition. The feature information F for one specified target feature ft is extracted from the map database 9. The feature information F extracted here includes position information and form information of the target feature ft as described above. The feature information F of the target feature ft extracted by the data extraction unit 6 is output to the image recognition unit 5 and the second vehicle position information acquisition unit 3.
More specifically, the target feature ft is one or more features around the position of the vehicle that falls within the imaging range of the imaging device 13 from the features whose feature information F is stored in the map database 9. Selected from things. In this example, the target feature setting unit 6a is based on the normal vehicle position information L1 acquired by the first vehicle position information acquisition unit 2 and the feature information F stored in the map database 9. One feature related to a road marking that is present in the closest position in the direction of travel within the road on which the vehicle is traveling (meaning the direction along the road, excluding the direction crossing the road) Set to ft. The range in which the target feature setting unit 6a searches for the target feature ft in the traveling direction of the host vehicle is defined within a predetermined distance. Therefore, the target feature ft is not set when there is no feature related to the road marking within a predetermined distance in the traveling direction of the host vehicle.

Further, the data extraction unit 6 extracts the map information M of the area requested by the navigation calculation unit 8 from the map database 9 for use in the guidance process by the navigation calculation unit 8, and sends it to the navigation calculation unit 8. Output.
1-5. Image Recognition Unit The image recognition unit 5 performs image recognition processing on the image information G acquired by the image information acquisition unit 4. In the present embodiment, the image recognition unit 5 performs image recognition processing on the image information G within the range defined by the image recognition range. At this time, the image recognition unit 5 performs image recognition processing of the target feature ft using the feature information F of the target feature ft extracted by the data extraction unit 6. Specifically, the image recognition unit 5 extracts the image information G in the image recognition range from the image information G acquired by the image information acquisition unit 4. At this time, the information of the imaging region of each image information G acquired by the image information acquisition unit 4 is calculated in advance based on the mounting position, mounting angle, angle of view, etc. of the imaging device 13 to the host vehicle. By using the positional relationship between the position and the imaging region, it can be acquired based on the normal vehicle position information L1. The image recognizing unit 5 extracts the image information G in the image recognition range based on the information on the imaging area of each image information G acquired in this way. Then, the image recognition unit 5 performs binarization processing, edge detection processing, and the like on the extracted image information G, and extracts contour information of the feature (road marking) included in the image information G. . Thereafter, the image recognition unit 5 compares the contour information of the extracted feature with the form information included in the feature information F of the target feature ft extracted by the data extraction unit 6, and whether they match. Determine whether or not. If the contour information of the feature and the form information included in the feature information F of the target feature ft match, it is determined that the image recognition of the target feature ft has succeeded, and the image recognition information is Output to the vehicle position information acquisition unit 3. If the image recognition of the target feature ft fails, the image recognition information is not output to the second vehicle position information acquisition unit 3, and therefore the normal vehicle position by the second vehicle position information acquisition unit 3. The information L1 is not acquired.

1-6. Second vehicle position information acquisition unit The second vehicle position information acquisition unit 3 is a target feature ft included in the result of image recognition processing by the image recognition unit 5 and the feature information F extracted by the data extraction unit 6. The high-accuracy own vehicle position information L2 is acquired based on the position information. In the present embodiment, the second vehicle position information acquisition unit 3 includes the target location included in the image recognition information obtained as a result of the image recognition processing by the image recognition unit 5 and the feature information F extracted by the data extraction unit 6. Based on the position information of the object ft, high-accuracy host vehicle position information L2 is acquired along the traveling direction of the host vehicle. Specifically, as shown in FIG. 3, the second vehicle position information acquisition unit 3 first sets the image recognition information by the image recognition unit 5, the attachment position, the attachment angle, and the angle of view of the imaging device 13. Based on this, the positional relationship between the host vehicle and the target feature ft when the image information G including the image of the target feature ft is acquired is calculated. Next, the second host vehicle position information acquisition unit 3 calculates the positional relationship between the host vehicle and the target feature ft and the target feature ft included in the feature information F extracted by the data extraction unit 6. Based on the position information of the vehicle, high-precision position information (high-precision vehicle position information L2) of the own vehicle based on the position information (feature information F) of the target feature ft in the traveling direction of the own vehicle is calculated. And get.
The high-accuracy vehicle position information L <b> 2 obtained by the second vehicle position information acquisition unit 3 is sent to the vehicle position determination unit 7.

1-7 Own vehicle position determination unit 7
The own vehicle position determination unit 7 includes the normal own vehicle position information L1 obtained by the first own vehicle position information acquisition unit 2, and the high-accuracy own vehicle position information L2 obtained by the second own vehicle position information acquisition unit 3. Based on the above, the guidance vehicle position information L3, which is the vehicle position used for guidance, is determined. In the present embodiment, as described above, the normal vehicle position information L1 is sent from the first vehicle position information acquisition unit 2 every several tens of milliseconds, and the second vehicle position information acquisition unit 3 Is a target feature ft to be image-recognized, the target feature ft is recognized well, and each time when the second vehicle position information acquisition unit 3 obtains high-accuracy vehicle position information L2. Then, the highly accurate own vehicle position information L2 is sent. Therefore, in the normal state where the high-precision vehicle position information L2 cannot be obtained, the vehicle position determination unit 7 sets the position as the guide vehicle position information L3 based on the normal vehicle position information L1. On the other hand, at the time when the target feature ft is image-recognized and the high-accuracy vehicle position information L2 is obtained, the vehicle position is based on the high-accuracy vehicle position information L2, and the position is guided vehicle position information L3. That is, when the highly accurate host vehicle position information L2 is obtained, this information L2 is given priority over the normal host vehicle position information L1. In FIG. 1, the guidance vehicle position information L <b> 3 is shown in a box indicating the vehicle position information determination unit 7 as “vehicle position information”.

Confidence level determination unit 7a
The own vehicle position determination unit 7 includes a confidence level determination unit 7a.
The degree-of-confidence determination unit 7a functions as a degree-of-confidence determination unit that determines an estimation error that is an estimated value of the error of the guidance vehicle position information L3 and determines the confidence level E of the guidance vehicle position information L3 according to the estimation error. To do. Here, the estimation error is an estimation value including a maximum error assuming that the acquisition condition of the normal vehicle position information L1 by the first vehicle position information acquisition unit 2 is the worst. In the present embodiment, the estimation error is an error in the traveling direction of the own vehicle (own vehicle position), and is fixed regardless of the distance factor error that increases according to the moving distance of the own vehicle and the moving distance of the own vehicle. Calculate by adding the factor error. Specifically, the confidence level determination unit 7a calculates the estimation error Y according to the following equation (1).
Y = aX + b + c (1)

  Here, X is the movement distance of the vehicle position from a predetermined starting position, and is obtained based on the guidance vehicle position information L3. The starting position is indicated by the guidance vehicle position information L3 after the determination when the guidance vehicle position information L3 is determined by the second vehicle position information acquisition unit 3 based on the high-accuracy vehicle position information L2. Position. Further, in a situation where the position of the own vehicle is normally calculated by autonomous navigation, a is a distance factor error coefficient that represents the maximum value per unit distance of the error integrated in proportion to the moving distance X. As an error factor that defines the distance factor error coefficient a, for example, a detection error of the distance sensor 12 or the azimuth sensor 11 is applicable. b is a starting point error indicating the maximum value of the error already included in the guidance vehicle position information L3 at the starting point position. As the error factors that define the starting point error b, for example, an error caused by image recognition accuracy by the image recognition unit 5, an error caused by a shift in the attachment position and attachment angle of the imaging device 13, and a feature of the target feature ft An error or the like due to the accuracy of the position information included in the information F is applicable. c is a calculation error representing the maximum value of the error caused by the error Y calculation process. As an error factor that defines the calculation error c, for example, an error due to rounding of a numerical value at the time of a delay calculation by a processing time corresponds. Therefore, in this example, aX is a distance factor error, and the starting point error b and the calculation error c are fixed factor errors.

  In order to accurately determine the estimation error Y, the distance factor coefficient a, the starting point error b, and the calculation error c are set to different values according to the traveling speed of the host vehicle (the moving speed of the host vehicle position). It is desirable. Therefore, in this example, the estimation error Y is calculated using a constant table (not shown) in which the values of the distance factor coefficient a, the starting point error b, and the calculation error c are stored for each predetermined speed range. Therefore, when the traveling speed of the host vehicle changes across a predetermined speed range, for each moving distance X in each speed range, a different distance factor coefficient a, starting point error b, and calculation error c are used. The calculation of the above equation (1) is performed to obtain the estimation error Y. In this example, the confidence level determination unit 7a uses the value of the estimation error Y obtained as described above for determining the confidence level E. Therefore, in this example, the smaller the value of the estimation error Y, the higher the confidence level E. FIG. 4 shows a reference confidence level E0 (corresponding to the reference accuracy) for comparing the levels of confidence level E with a one-dot chain line. A region with high confidence E is a region below the dashed-dotted line, and a region with low confidence E is a region above the dashed-dotted line.

  FIG. 4 is a diagram showing an example of a change in the estimation error Y, that is, the degree of confidence E when the host vehicle travels at a substantially constant speed. As shown in this figure, the estimation error Y at the starting position (X = 0) is Y = b + c, and the estimation error Y increases in proportion to the movement distance X from there. In this example, when the estimation error Y increases beyond the error circle radius of the vehicle position information acquired by the GPS receiver 10 and reaches the GPS correction boundary, it is acquired by the GPS receiver 10. The vehicle position information L is corrected based on the vehicle position information. At that time, the estimation error Y is corrected so as to coincide with the GPS error circle radius. Then, as will be described later, based on the image recognition result of the target feature ft by the image recognition unit 5, the high-accuracy vehicle position information L2 is obtained by the second vehicle position information acquisition unit 3, and based on this information When the guidance vehicle position information L3 is determined, the position indicated by the guidance vehicle position information L3 is the starting position, and the movement distance X is zero. Thereby, the estimation error Y becomes Y = b + c.

1-8 Own Vehicle Position Determination Process Regarding the configuration described above, the own vehicle position determination process performed in the present embodiment will be described with reference to FIG. FIG. 5 is a flowchart showing a procedure for determining the vehicle position and confidence level.
This own vehicle position determination processing is performed at least every time the first own vehicle position information acquisition unit 2 acquires the normal own vehicle position information L1 and the guidance own vehicle position information L3 and the confidence level associated with the own vehicle position. E is a process for determining E. When high-accuracy vehicle position information L2 is obtained from the second vehicle position information acquisition unit 3, the information is preferentially used to determine the guidance vehicle position information L3. The

In the process, first, the normal vehicle position information L1 is acquired by the first vehicle position information acquisition unit 2 (step # 01). By acquiring this information, the data extraction unit 6 can confirm the presence / absence of the target feature ft, and also performs processing in the second vehicle position information acquisition unit 3 and guidance in the vehicle position determination unit 7. The vehicle position information L3 can be determined. The data processing unit 6 checks whether or not there is an image-recognizable feature (this feature is the target feature ft) in the vicinity of the current vehicle position, and if there is the target feature ft. The information is sent to the image recognition unit 5 (step # 02: yes). The image recognition unit 5 recognizes the target feature ft in the image information sent from the image information acquisition unit 4 (step # 03), and sends the image recognition information to the second vehicle position information acquisition unit 3. send. The second host vehicle position information acquisition unit 3 acquires high-precision host vehicle position information L2 (step # 04), and based on the information, the host vehicle position determination unit 7 determines the host vehicle position (in accordance with the guide host vehicle position information L3). Is determined (step # 05). Furthermore, regarding the confidence level E, the confidence level E is set to be high by the process in the confidence level determination unit 7a (step # 06). On the other hand, when there is no target feature ft, the own vehicle position determination unit 7 determines the own vehicle position (guide own vehicle position information L3) based on the normal own vehicle position information L1 (step # 07). At this time, the confidence level E is set to be low by the process in the confidence level determination unit 7a (step # 08).
The guidance vehicle position information L3 and the confidence level E determined in this way are sent to the navigation calculation unit 8.
That is, the presence or absence of the target feature ft from which the high-accuracy vehicle position information L2 can be obtained as viewed from the current vehicle position is determined. If there is no target feature ft, the normal vehicle position is obtained according to the normal vehicle position acquisition procedure. The vehicle position is determined based on the information L1. On the other hand, when there is the target feature ft, the target feature ft is specified to acquire the high-accuracy host vehicle position information L2, and the high-accuracy host vehicle position information L2 is acquired. Is determined.

1-9. Navigation calculation unit The navigation calculation unit 8 provides navigation functions such as displaying the vehicle position, setting the route from the departure point to the destination (the route setting unit 8a is responsible for), route guidance to the destination, and destination search. An arithmetic processing means that operates according to an application program for execution. For example, the navigation calculation unit 8 acquires the map information M around the host vehicle from the map database 9 by the data extraction unit 6 and displays a map image on the display device 14, and also displays the map image on the map image. Based on the vehicle position information L3, the vehicle position mark M is displayed in a superimposed manner. Further, the navigation calculation unit 8 determines one or both of the display device 14 and the audio output device 15 based on the guidance route from the departure point to the destination calculated by a known method and the guidance vehicle position information L3. Use to guide. Although not shown, the navigation calculation unit 8 has various other known configurations necessary for a navigation device such as a remote controller and a user interface such as a touch panel provided integrally with the display device 14. It is connected.

  Now, in this embodiment, since it is a problem that the route is off, it is determined whether or not the guidance route that has been obtained in advance has been off, whether or not to reroute in the state where the off-route has occurred in this way, and reroute There is also an application program for controlling the route calculation when performing

  The off-route determination is performed by the off-route determination unit 8b, and it is determined whether or not the vehicle position is out of the previously set guidance route. That is, it is determined whether or not the vehicle position is on the guidance route according to the guidance vehicle position information L3 input separately to the navigation calculation unit 8, and if it is on the route, the route is not deviated. If it is not on the guidance route, it is determined that the route is off.

  The reroute determination / control is performed by the reroute determination / control unit 8c. As will be described later in detail according to the flow, whether or not reroute is possible is determined based on the confidence level E sent separately, and the reroute is necessary and confident. When it is determined that the degree E is high and an accurate reroute is possible, the route setting unit 8a is operated to calculate the route of the guidance route from the departure point to the destination with the current vehicle position as the departure point. On the other hand, even if rerouting is necessary, if the degree of confidence E is not low and accurate rerouting is not always possible, processing for holding the rerouting is executed until the degree of confidence E increases.

1-10. Next, the reroute process accompanying the off-route executed in the navigation device 1 will be described. FIG. 6A shows a situation in which such a reroute process is necessary, and FIG. 7 is a flowchart showing a processing order when the reroute is executed.

  In FIG. 6, the guidance route is indicated by a thick solid line. In the illustrated example, there is a narrow-angle branch from the departure point to the destination, indicating that it is necessary to enter the route shown on the upper and lower sides of the figure (the left side in the traveling direction). Furthermore, the thick broken line shows the rerouted guide route. FIG. 6B shows a situation when executing reroute on the conventional side, and the x mark shown in FIG. 6B is the conventional reroute start position. This position does not require the presence of the target feature ft.

As shown in FIG. 7, the navigation device 1 first receives information on a departure place and a destination necessary for route search (step # 11). Based on these pieces of information, the route setting unit 8a performs route setting (step # 12).
The navigation calculation unit 8 acquires the vehicle position (specifically, the guidance vehicle position information L3: the same applies hereinafter) and the confidence level E determined by the vehicle position determination unit 7 (step # 13). Here, if the vehicle position has reached the destination, the guidance is finished (step # 14: yes). On the other hand, when the destination has not been reached (step # 14: no), the off-route determination unit 8b sequentially determines whether there is a off-route (step # 15). If the route has not been deviated (step # 15: no), the guidance is continued along the currently set guidance route (step # 16). On the other hand, if the route has been deviated (step # 15: yes), a new vehicle position and confidence E are acquired (step # 17). Then, a process based on the confidence level E is executed (step # 18). That is, when the confidence level E is low (specifically, lower than the reference confidence level E0: the same applies hereinafter), the guidance is continued without performing the reroute process (step # 18: no). On the other hand, if the confidence level E is high (specifically, higher than the reference confidence level E0: the same applies hereinafter), the current position is set as the departure place (step # 19), and the processing by the route processing unit 8a is executed. Guidance is executed based on the rerouted guidance route (step # 18: yes).
In this way, it is possible to determine a new guide route on the basis of the own vehicle position with high accuracy, and to cope with the off-route well.

2. Second Embodiment Next, a second embodiment of the present invention will be described. FIG. 8 is a block diagram illustrating a schematic configuration of the navigation device 1 according to the present embodiment. The navigation device 1 according to the present embodiment is different from the first embodiment in which reroute is a problem in that the line determination is performed. Since the configuration on the processing upper side than the navigation calculation unit 8 of the navigation device 1 is the same as that described so far, only different parts will be described.
2-1. Navigation Calculation Unit The navigation calculation unit 8 includes a route setting unit 8a and determines whether or not the user has taken a previously obtained guidance route in order to have a problem with the line. Thus, an application program for determining whether or not guidance based on a train line may be started and executing control when starting guidance is provided.

  The lane determination is performed by the lane determination unit 8d, and it is determined whether or not the vehicle position is on the previously set guidance route. That is, it is determined whether or not the guidance vehicle position information L3 input separately to the navigation calculation unit 8 is on the guidance route. If the guidance vehicle location information L3 is on the route, it is determined that the vehicle is on the route. If not, it is determined that the vehicle has not been boarded yet.

  The guidance start determination / control is performed by the guidance start determination / control unit 8e, and, as will be described in detail later in accordance with the flow, it is determined whether or not the route guidance can be started based on the confidence level E sent separately, If it is determined that the degree of confidence E is high and accurate guidance is possible, guidance is started. On the other hand, when the degree of confidence E is low and it is not always possible to provide guidance based on the correct vehicle position, processing for delaying the guidance start is executed until the degree of confidence E becomes high.

2-2. Guidance Start Process Associated with a Line Next, a guidance start process associated with a line executed in the navigation device 1 will be described. FIG. 9 shows a situation in which such a route guidance process is necessary, and FIG. 10 is a flowchart showing a processing order when a reroute is executed.

  In FIG. 9, the guidance route is indicated by a solid line. This figure shows the relationship of the actual departure location with respect to the guide route. In the example shown in the figure, there is an area that is a so-called narrow street where the guidance route cannot be set from the departure point to the guidance route, and the narrow street is indicated by a broken line in the figure, and it can be seen at the connection portion between the broken line and the solid line. In addition, it is necessary to start the guidance after completely getting on the guidance route. FIG. 9B shows a situation when the conventional route guidance process is executed, and the x mark shown in FIG. 9B is the start position of the conventional route guidance process. This position does not require the presence of the target feature.

  As shown in FIG. 10, the navigation apparatus 1 first receives information on the departure place and the destination necessary for route search (step # 21). Based on these pieces of information, the route setting unit 8a performs route setting within a range in which a guidance route can be set (step # 22).

The navigation calculation unit 8 acquires the host vehicle position and the confidence level E determined by the host vehicle position determination unit 7 (step # 23). Here, if the vehicle position has reached the destination, the navigation will be finished (step # 24: yes). On the other hand, when the destination has not been reached (step # 24: no), it is sequentially determined whether or not the line determination unit 8d is on the line (step # 25). And when it is not on boarding (step # 25: no), guidance along a guidance route is not started but it waits for a boarding. On the other hand, if it can be determined that the vehicle is on the line (step # 25: yes), a new vehicle position and confidence E are acquired (step # 26). Then, processing based on the confidence level E is executed (step # 27). That is, when the confidence level E is low, the current state is maintained until the confidence level E increases without starting guidance (step # 27: no). On the other hand, if the degree of confidence E is high, guidance along the guidance route is started (step # 28).
In this way, it is possible to satisfactorily execute guidance after getting on the basis of the vehicle position with high accuracy.

3. Third Embodiment A third embodiment of the present invention will be described. FIG. 11 is a block diagram illustrating a schematic configuration of the navigation device 1 according to the present embodiment. The navigation device 1 according to the present embodiment is different from the first embodiment in which reroute is a problem in that it performs a turn determination and displays an enlarged display of a turn portion on a guide route. Since the configuration on the processing upper side than the navigation calculation unit 8 of the navigation device 1 is the same as that described so far, only different parts will be described.

3-1. Navigation Calculation Unit Also in this embodiment, the navigation calculation unit 8 includes the route setting unit 8a and has a curved portion on the guide route, and this causes a problem of stopping the enlarged display after the enlarged display. In this way, an application program is also provided for determining whether or not to stop the enlarged display as it passes through the curved portion and entering the curved portion and displaying the enlarged portion, and controlling the stop of the enlarged display. ing.

The display change process is performed by the display change processing unit 8f. If there is a turning part on the traveling side with respect to the previously set guidance route, the guidance display state is changed. That is, when there is a curved portion on the guidance route of the own vehicle, the enlarged display of the curved portion is performed on the normal guidance display based on an enlarged display start command which is a display change control command generated separately. FIG. 12 shows a display screen in which enlarged display is performed on the upper right side in the figure when the curved portion is an intersection in the present embodiment.
Further, the display change processing unit 8f executes display change processing for stopping the enlarged display based on an enlarged display stop command that is a display change control command from the enlarged display determination / control unit 8h.

  The curve determination process is performed by the curve determination unit 8g, and it is determined whether or not there is a curve part on the traveling side with respect to the previously set guidance route. And when approaching such a curved part, the said enlarged display start command is produced | generated and sent to the display change process part 8f.

Larger image stop determination and control performed by the enlargement display determination and control section 8h, as later described in detail with FIG flow chart (FIG. 13), based on the confidence level E come otherwise sent, enlarge start command determining whether the enlarged display of stopped being performed on the basis of. Specifically, when entering the bent portion, passing through the bent portion, and when it is determined that the degree of confidence E is high and the enlarged display can be stopped with the passage, the enlarged display is stopped (that is, , Generate an enlarged display stop command). On the other hand, if the degree of confidence E is low and it is not always possible to stop the enlarged display, the enlarged display is held until the degree of confidence E becomes higher (the enlarged display stop command is not generated).

  In FIG. 12, the guidance route is indicated by a solid line, and the vehicle position is indicated by a circled triangle mark m. Further, the enlarged display is displayed on the upper right side. FIG. 12B shows the situation when the conventional enlarged display stop process is executed, and the x mark shown in FIG. 12B is the start position of the conventional enlarged display stop process. This position does not require the presence of the target feature.

3-2. Enlargement display stop processing associated with bending

  As shown in FIG. 13, the navigation device 1 first receives information on a departure place and a destination necessary for route search (step # 31). Based on these pieces of information, the route setting unit 8a performs route setting (step # 32).

The navigation calculation unit 8 acquires the vehicle position and the confidence level E determined by the vehicle position determination unit 7 (step # 33). Here, if the vehicle position has reached the destination, the navigation is finished (step # 34: yes). On the other hand, if the destination has not been reached (step # 34: no), the bending determination unit 8g determines whether there is a bending portion ahead of the traveling (step # 35). If there is no curved portion (step # 35: no), the guidance along the guidance route is continued without performing enlarged display (step # 36). On the other hand, when it can be determined that the vehicle is approaching the bend (step # 35: yes), as shown in FIG. 12A, an enlarged display is displayed in addition to the previous guidance display (step # 37). In this enlarged display state, a new vehicle position / confidence level E is acquired as the vehicle travels (step # 38). For example, when making a left turn at an intersection, the approach side pedestrian crossing after the left turn becomes the target feature ft, and the vehicle position is determined based on the target feature ft, and the confidence E is increased. Therefore, processing based on the confidence level E is executed (step # 39). That is, when the confidence level E is low (step # 39: no), the enlarged display state is maintained until the confidence level E is increased without stopping the enlarged display (step # 40). On the other hand, when the degree of confidence E is high (step # 39: yes), the enlarged display is stopped (step # 41), and guidance along the guidance route is performed without the enlarged display (step # 42).
In this way, it is possible to determine the stop timing of the enlarged display from the own vehicle position with high accuracy and appropriately provide the enlarged display.

4). Fourth Embodiment A fourth embodiment of the present invention will be described. FIG. 14 is a block diagram illustrating a schematic configuration of the navigation device 1 according to the present embodiment. The navigation device 1 according to the present embodiment is different from the third embodiment in which a problem is caused in bending in that branch determination is performed and an enlarged display of a branch portion on the guidance route is displayed. In this navigation device 1 as well, the configuration on the processing side from the navigation calculation unit is the same as that described so far, so only different parts will be described. Furthermore, the third embodiment is different in that the bending determination unit 8g is a branch determination unit 8i, and the enlarged display determination / control unit 8j determines a branch instead of a curve.
FIG. 15 is a flowchart showing a processing order when the enlarged display processing of the branch is performed and the enlarged display is stopped.

4-1. Navigation Calculation Unit Also in this embodiment, the navigation calculation unit 8 includes the route setting unit 8a, and there is a branch on the guide route, and the problem is that the enlarged display stops after the enlarged display. Then, an application program for determining whether or not the branch is approaching, determining whether or not to stop the enlarged display in the state of entering the branch and displaying the enlarged display, and controlling the stop of the enlarged display It has.
The display change process is performed by the display change processing unit 8f. If there is a branch on the traveling side with respect to the previously set guidance route, the guidance display state is changed. That is, when there is a branch on the guidance route of the own vehicle, an enlarged display of the branch portion is performed on the normal guidance display based on an enlarged display start command that is a separately generated display change control command.
Further, the display change processing unit 8f executes display change processing for stopping the enlarged display based on an enlarged display stop command that is a display change control command from the enlarged display determination / control unit 8j.

  The branch determination process is performed by the branch determination processing unit 8i, and it is determined whether or not there is a branch unit on the traveling side for the previously set guidance route. And when approaching such a branch part, the said enlarged display start command is produced | generated and it sends to a display change process part.

  Enlargement display stop determination / control is performed by the enlargement display determination / control unit 8j, and as described later in detail according to the flow, it is determined whether or not the enlargement display can be stopped based on the confidence level E sent separately, When entering the branching section, the branching is completed, and when it is determined that the degree of confidence E is high and the enlarged display can be stopped, the enlarged display is stopped (that is, the enlarged display stop command is issued). To generate). On the other hand, if the degree of confidence E is low and it is not always possible to stop the enlarged display, a process of maintaining the enlarged display is executed until the degree of confidence E becomes higher (the enlarged display stop command is not generated).

4-2. Enlargement display stop processing associated with branching

  As shown in FIG. 15, the navigation device 1 first receives information on a departure place and a destination necessary for route search (step # 51). Based on these pieces of information, the route setting unit 8a performs route setting (step # 52).

The navigation calculation unit 8 acquires the vehicle position and the confidence level E determined by the vehicle position determination unit 7 (step # 53). Here, if the vehicle position has reached the destination, the navigation is finished (step # 54: yes). On the other hand, if the destination has not been reached (step # 54: no), the branch determination unit 8i determines whether or not there is a branch ahead (step # 55). If there is no branch (step # 55: no), guidance along the guidance route is continued without performing enlarged display (step # 56). On the other hand, when it can be determined that the vehicle is approaching a branch (step # 55: yes), an enlarged display is displayed in addition to the previous guidance display (step # 57). With the enlarged display in this way, a new host vehicle position / confidence level E is acquired as the host vehicle advances (step # 58). For example, when the right branch road (straight path) is selected at the branch point shown in FIG. 3, the pedestrian crossing on the entry side after passing through the branch point becomes the target feature ft, and based on the target feature ft. As a result, the vehicle position is determined and the confidence level E is increased. Therefore, processing based on the confidence level E is executed (step # 59). That is, when the confidence level E is low (step # 59: no), the display state of the enlarged display is maintained until the confidence level E is increased without stopping the enlarged display (step # 60). On the other hand, when the degree of confidence E is high (step # 59: yes), the enlarged display is stopped (step # 61), and guidance along the guidance route is performed without the enlarged display (step # 62).
In this way, it is possible to determine the stop timing of the enlarged display from the own vehicle position with high accuracy and appropriately provide the enlarged display.

5. Other Embodiments (1) In each of the above embodiments, the first vehicle position information acquisition means (first vehicle position information acquisition unit 2) is autonomous obtained by GPS information obtained from the global positioning system and autonomous navigation. The second vehicle position information acquisition means is configured to acquire the first vehicle position information based on both of the navigation information, and the second vehicle position information acquisition means is configured to acquire the second information based on the feature information that is information on the feature imaged by the imaging device. A configuration for obtaining own vehicle position information is shown.
However, as the first vehicle position information acquisition means, the first vehicle position information may be obtained from either GPS information obtained from the global positioning system or autonomous navigation information obtained by autonomous navigation. . Furthermore, as means for obtaining own vehicle position information with higher accuracy than the first own vehicle position information, position information obtained from a road traffic information communication system (VICS) can be mentioned. For example, when this system is used, an area where an optical beacon can be received is limited to a relatively narrow area depending on the position of the transmission facility. Therefore, it is possible to acquire the position of the vehicle that has received the VICS information from the position information of the transmission facility, or to acquire the position information of the vehicle related to the traveling lane. Therefore, you may employ | adopt the structure which acquires 2nd own-vehicle positional information based on the positional information obtained from the said road traffic information communication system.

FIG. 16 is a block diagram showing a schematic configuration of a navigation device according to another embodiment for obtaining the vehicle position information from such a road traffic information communication system, and FIG. 17 is a diagram of the navigation device 1 according to this another embodiment. Indicates the usage state.
As shown in FIG. 17, the information transmission equipment 100 which comprises a road traffic information communication system has shown the structure provided above the road, and the VICS information provided by the optical beacon from this transmission equipment 100 on the vehicle side is shown. Can receive. The own vehicle is provided with a VICS receiving device 40, which receives VICS information. That is, as shown in FIG. 16, on the navigation device 1 side, a transmission facility position specifying unit 50 that specifies the position (that is, the position of the transmission facility 100) that received the optical beacon from the VICS information received by the VICS reception device 40. The position information specified by this part is delivered to the second vehicle position information acquisition unit 3. In this configuration, the position in the traveling direction along the road and the traveling lane can be accurately acquired as the vehicle position. Since such information is more accurate than information obtained by at least autonomous navigation or the like, it can be used to obtain the second vehicle position information referred to in the present application.
(2) In the above embodiment, the example in which the confidence level E is used as the accuracy index of the guidance vehicle position information has been shown. However, the estimation error Y shown in FIG. When the guidance vehicle position information L3 is determined, the source information of the information used as the basis may be used as an accuracy index.

(3) In the above embodiment, an example in which there are two means for acquiring own vehicle position information has been shown. However, there is an own vehicle position acquisition means capable of obtaining own vehicle position information with different accuracy. There should be at least two.

(4) In the first embodiment for executing the reroute guidance process described above, the accuracy of the vehicle position information used for the determination is not a problem with regard to the determination of deviation from the route. In addition, it is good also as what determines the off-route only after obtaining the second vehicle position information referred to in the present application.

(5) In the second embodiment for executing the above-described route guidance process, the accuracy of the vehicle position information used for the determination is not a problem for the route determination, but this determination itself is performed. In this case, it may be determined that the route has been off after obtaining the second vehicle position information referred to in the present application.

(6) In the third embodiment and the fourth embodiment described above, in order to provide good guidance at a specific point, guidance is provided by showing an enlarged view displayed up to the road width at the specific point. However, as long as it is a display in which the detailed status of the specific point can be understood, the display status may be any more detailed than the display status executed so far, and the display status is not questioned. That is, guidance may be provided by representing intersections and branch points with different scales.

  A navigation device can be obtained in which the guidance processing is adapted to the driver's feeling and can be made accurate and accurate.

The block diagram which shows schematic structure of the navigation apparatus which concerns on 1st embodiment of this invention. Explanatory drawing which shows the example of a structure of the map information and feature information which are stored in the map database Explanatory drawing which shows the determination status of the own vehicle position in a 2nd own vehicle position information acquisition part The figure which showed the example of the change of a presumed error, ie, the confidence level E, when the own vehicle drive | works at substantially constant speed Flow chart showing own vehicle position and confidence level determination processing procedure Explanatory drawing of the reroute start position in the present invention and the prior art The flowchart which shows the reroute start processing procedure which concerns on 1st embodiment of this invention. The block diagram which shows schematic structure of the navigation apparatus which concerns on 2nd embodiment of this invention. Explanatory drawing of the guidance start position accompanying the line determination and the line in the present invention and the prior art The flowchart which shows the square / guidance start processing procedure which concerns on 2nd embodiment of this invention The explanatory view of the comparative example of the setting of the image recognition range which concerns on 1st embodiment of this invention The block diagram which shows schematic structure of the navigation apparatus which concerns on 3rd embodiment of this invention. Explanatory drawing of the enlarged display accompanying bending in this invention and a prior art The flowchart which shows the enlarged display which concerns on 3rd embodiment of this invention, and its stop process sequence The block diagram which shows schematic structure of the navigation apparatus which concerns on 4th embodiment of this invention. The flowchart which shows the enlarged display which concerns on 4th embodiment of this invention, and its stop process sequence The block diagram which shows schematic structure of the navigation apparatus which concerns on another embodiment which acquires the own vehicle position information from a road traffic information communication system Explanatory drawing which shows the use condition of the navigation apparatus which concerns on another embodiment which obtains own vehicle position information from a road traffic information communication system

Explanation of symbols

1: Navigation device 2: First vehicle position information acquisition unit (first vehicle position information acquisition means)
3: Second host vehicle position information acquisition unit (second host vehicle position information acquisition means)
7: Own vehicle position determination unit (own vehicle position determination means)
7a: Confidence level determination unit (confidence level determination means)
8: Navigation calculation unit (guidance means)
8a: Route setting unit (route setting means)
8b: Route off determination unit (route off determination means)
8c: Reroute determination / control unit (guidance means)
8d: Line determination unit (Line determination unit)
8e: Guidance start determination / control unit (guidance means)
8f: Display change processing unit (display change processing means)
8g: Bending determination unit (detail display necessary point determining means)
8h: Enlarged display determination / control unit (guidance means)
8i: Branch determination unit (detail display necessary point determination means)
8j: Enlarged display determination / control unit (guidance means)
9: Map database

Claims (14)

It includes a route setting unit that sets a guidance route from the information of the start and destination, based on the relationship between the vehicle position information and the guidance route obtained by the vehicle position information obtaining unit, according to the prior SL guiding route A navigation device for executing the guidance,
First vehicle position information acquisition means for acquiring first vehicle position information which is vehicle position information;
Second host vehicle position information acquisition means for acquiring second host vehicle position information which is host position information with higher accuracy than the first host vehicle position information ;
Based on the first vehicle position information and the second vehicle position information, vehicle position determination means for determining guided vehicle position information that is vehicle position information used for guidance ;
Guidance means for performing guidance based on the guidance route and the guidance vehicle position information ,
When it is determined that the state change of the guidance process is necessary, the guidance unit starts the state change when the accuracy of the guidance vehicle position information is equal to or higher than a preset reference accuracy,
When a change in the state of the guidance processing is determined to be necessary, when the accuracy of the guiding vehicle position information is lower than the reference accuracy, pending before Symbol status change, the guide itself during the pending to start the guidance processing in the case where the accuracy of the vehicle position information is higher than the reference accuracy, the navigation device. A fixed factor error including an error included in the starting position, with the position indicated by the guidance own vehicle position information determined based on the second own vehicle position information as a starting position, and the first own vehicle position information An error including a distance factor error that increases in accordance with a moving distance from the starting position of the position indicated by the vehicle position information calculated based on the estimated vehicle position information as an estimation error. As a value that increases as the error value decreases, a confidence level determination unit that determines the confidence level of the guidance vehicle position information is provided,
The navigation device according to claim 1 , wherein the guidance unit uses the confidence level as the accuracy of the guidance vehicle position information . The first own vehicle position information acquisition means obtains the first own vehicle position information based on one or both of GPS information obtained from a global positioning system and autonomous navigation information obtained by autonomous navigation;
The second vehicle position information acquisition unit, a navigation device according to claim 1, wherein obtaining said second vehicle position information based on the feature information which is information relating to the imaged feature by the imaging device. The first own vehicle position information acquisition means obtains the first own vehicle position information based on one or both of GPS information obtained from a global positioning system and autonomous navigation information obtained by autonomous navigation;
The navigation device according to claim 1 or 2, wherein the second vehicle position information acquisition means obtains the second vehicle position information based on position information obtained from a road traffic information communication system. A route off determination means for determining whether or not the vehicle position deviates from the guidance route;
A reroute process for newly setting a guide route for reaching the destination from the vehicle position is determined in a state where the vehicle position is determined to be out of the guide route by the route deviation determination means. ,
The start of the reroute process as the guide process is suspended when the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, and the reroute process is started when the accuracy is higher than the reference accuracy. The navigation device according to any one of to 4 . Comprising a line determination means for determining whether or not the vehicle position is on the guide route;
In the state where it is determined that the vehicle is on the guide route by the line determination means, the guide according to the guide route can be started.
When the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, the start of guidance according to the guidance route as the guidance processing is suspended, and when the accuracy is higher than the reference accuracy, the guidance route is followed. navigation device according to any one of claims 1-4 for starting a guidance. It is provided with detailed display necessary point determining means for determining whether or not there is a detailed display necessary point that requires detailed display on the guidance route, and the detailed display is required to pass through the detailed display necessary point. Accordingly, the detailed display can be stopped,
The detailed display is stopped as the guidance processing when the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, and the detailed display is stopped when the accuracy is higher than the reference accuracy. The navigation apparatus as described in any one of 1-4 . The navigation device according to claim 7, wherein the detailed display necessary point is one of an intersection where a plurality of roads intersect or a branch point where a road branches. A route setting step for setting a guide route from information of a departure place and a destination, and a vehicle position acquisition step for obtaining own vehicle position information are executed, and based on the relationship between the own vehicle position information and the guide route, A navigation method for performing guidance according to the guidance route,
A first own vehicle position information acquisition step of acquiring first own vehicle position information which is own vehicle position information;
A second host vehicle position information acquisition step for acquiring second host vehicle position information, which is host position information with higher accuracy than the first host vehicle position information ;
Based on the first vehicle position information and the second vehicle position information, a vehicle position determination step for determining guided vehicle position information that is vehicle position information used for guidance ;
Performing guidance based on the guidance route and the guidance vehicle position information ,
In the guidance process, when it is determined that the state change of the guidance process is necessary, if the accuracy of the guidance vehicle position information is equal to or higher than a preset reference accuracy, the state change is started.
When a change in the state of the guidance processing is determined to be necessary, when the accuracy of the guiding vehicle position information is lower than the reference accuracy, pending before Symbol status change, the guide itself during the pending the accuracy of vehicle position information starts the guidance processing if it becomes higher than the reference accuracy, the navigation method. A fixed factor error including an error included in the starting position, with the position indicated by the guidance own vehicle position information determined based on the second own vehicle position information as a starting position, and the first own vehicle position information An error including a distance factor error that increases in accordance with a moving distance from the starting position of the position indicated by the vehicle position information calculated based on the estimated vehicle position information as an estimation error. As a value that increases as the error value decreases, a confidence level determination step of determining the confidence level of the guidance vehicle position information is provided,
The navigation method according to claim 9 , wherein the guidance unit uses the confidence level as the accuracy of the guidance vehicle position information . A route deviation determination process is performed to determine whether or not the vehicle position has deviated from the guide route, and the vehicle position is reached from the vehicle position with the vehicle position determined to be deviated from the guide route. To execute the reroute process to set a new guide route for
The start of the reroute process as the guide is maintained when the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, and then the reroute process is started when the accuracy is higher than the reference accuracy. The navigation method according to 9 or 10 . Execute a route determination step for determining whether or not the vehicle position is on the guide route, and start guidance according to the guide route in a state where it is determined that the vehicle is on the guide route. To
When the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, the start of guidance according to the guidance route as the guidance is suspended, and then the guidance route is entered when the accuracy is higher than the reference accuracy. The navigation method according to claim 9 or 10 , wherein the following guidance is started. A detailed display necessary point determining step for determining whether or not there is a detailed display necessary point that requires detailed display on the guidance route is executed, and the detailed display is required to pass through the detailed display necessary point. At the same time, to stop the detailed display,
The detailed display as the guidance is suspended when the accuracy of the guidance vehicle position information is lower than a preset reference accuracy, and then the detailed display is stopped when the accuracy is higher than the reference accuracy. Item 11. The navigation method according to Item 9 or 10 . The navigation method according to claim 13, wherein the detailed display necessary point is one of an intersection where a plurality of roads intersect or a branch point where roads branch.

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