JP2007155503A - Vehicle navigation apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To decide whether a U-turn has been made by a vehicle with high precision and display a vehicle mark on a road on which the vehicle is traveling immediately when the U-turn has been made. <P>SOLUTION: When the vehicle has made a U-turn, its traveling direction before the starting of the U-turn and the direction after the termination of the U-turn are nearly opposite. It can be decided easily and with high precision whether the vehicle has made a U-turn or not by setting a dead area with reference to a traveling direction change starting point at which the vehicle has started a change of its traveling direction and on the basis of an area entering direction at a dead area entering position and an area leaving traveling direction at a leaving position. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle navigation device that can immediately adjust the current position of a vehicle on a road on which the vehicle travels even when the vehicle has changed direction (U-turn).

  Conventionally, in a car navigation apparatus, a map matching process is generally employed in order to calculate an accurate current position of a vehicle. In this map matching process, first, radio navigation using GPS or the like, or self-contained navigation in which the current position is cumulatively estimated based on detection signals from a vehicle speed sensor and a direction sensor (gyroscope, geomagnetic sensor, etc.) A traveling locus including the current position of the vehicle is obtained by hybrid navigation combining these radio navigation and independent navigation. Then, by comparing the travel locus with road data stored in the map database, the road on which the vehicle is traveling is estimated, and the correct current position of the vehicle is obtained.

  Based on FIGS. 7A, 7B, and 7C, the principle of the map matching process will be briefly described. For example, all roads connected to the intersection where the vehicle has reached are selected as candidate roads that the vehicle may pass next. In the example shown in FIG. 7A, roads a, b, and c are selected as candidate roads. A comparison is made between the road shape of the candidate road selected in this way and the shape of the vehicle trajectory (FIG. 7B), and the road with the highest correlation is regarded as the road on which the vehicle is traveling. Confirm the vehicle position. In the example shown in FIG. 7C, since the correlation of the road b is the highest, the vehicle is regarded as traveling on the road b, and the vehicle position is determined on the road b. Such processing is performed for a certain time or every time the vehicle travels a certain distance, and the vehicle position is always determined on the road.

Here, Patent Document 1 discloses a navigation device that always displays road information corresponding to the traveling direction of a vehicle even if the vehicle makes a U-turn. This navigation device receives road information such as distance to a branch point and traffic information such as traffic congestion, construction, and regulations transmitted from a beacon transmitter, and main direction information corresponding to the traveling direction and its information. The information is stored separately in the subordinate direction information corresponding to the opposite direction. Based on the detection results of the vehicle speed sensor, the rotation angle sensor, the azimuth sensor, etc., it is detected whether the vehicle has made a U-turn by referring to the road map around the current position while calculating the turning radius of the vehicle. . When the U-turn of the vehicle is detected, the information stored as the secondary direction information is displayed on the display.
JP-A-5-248881

  Although the above-described Patent Document 1 does not describe a specific U-turn detection method, this U-turn detection is actually highly technically difficult. This is because, regardless of whether it is radio navigation or self-contained navigation, the calculated vehicle position may contain some errors, and in the map matching process, the road where the vehicle is connected to the current road This is because it is premised on traveling.

  For this reason, when the vehicle makes a U-turn, the current position of the vehicle may be matched with the wrong road by the map matching process. In such a case, in order for the vehicle to return to the correct position on the road on the map, it is necessary for the vehicle to travel a certain distance and to accumulate travel locus data for performing map matching.

  The present invention has been made in view of the above-described points, and accurately determines whether or not the vehicle has undergone a turn (U-turn), and when the turn has been made, the vehicle travels. It is an object of the present invention to provide a vehicle navigation device capable of immediately displaying a vehicle mark on a road.

In order to achieve the above object, a vehicle navigation device according to claim 1 is provided.
A display unit for displaying at least a vehicle mark indicating a current position and a traveling direction of the vehicle and a map around the vehicle mark;
Measuring means for measuring the current position and direction of travel of the vehicle;
Based on the current position measured by the measuring means, a traveling locus calculating means for calculating a traveling locus of the vehicle;
Map data storage means for storing map data;
A map that determines the road on which the vehicle is traveling by comparing the shape of the road near the current position of the vehicle with the shape of the traveling locus calculated by the traveling locus calculation means in the map data stored by the map data storage means Map matching means for executing the matching process;
A vehicle navigation device comprising display control means for displaying a vehicle mark and a surrounding map on a display unit so that the vehicle mark is located on a road determined by a map matching means,
When the traveling direction of the vehicle changes, the vehicle includes a direction change determination means for determining whether or not the vehicle has changed direction based on the direction of travel before the start of the change and the direction of travel after the end of the change,
The map matching means, when it is determined by the direction change determination means that the vehicle has changed direction, determines the road on which the vehicle was traveling before the change of traveling direction as the road when the vehicle is traveling. And

  Here, whether or not the vehicle has changed direction (U-turn) is determined based on, for example, whether or not the cumulative value of the change in the traveling direction of the vehicle detected by a direction sensor or the like has become approximately 180 °. Can be considered.

  However, when the vehicle actually changes direction, if the road to be changed is wide, the accumulated value of the change in the traveling direction detected by the direction sensor is 180 ° as shown in FIG. It may be greatly exceeded. Further, when the road width of the road to change direction is narrow, as shown in FIG. 5B, it may be necessary to reverse the direction of travel of the vehicle to perform turning. In this way, in the process of turning the vehicle, the traveling direction is changed beyond 180 °, or the traveling direction is reversed and the turning is performed. For this reason, it is difficult to determine whether or not the vehicle has changed direction based on the traveling direction data in the middle of the change in the traveling direction.

  In view of such a point, in the vehicle navigation device according to claim 1, when the traveling direction of the vehicle changes, the vehicle is based on the traveling direction before the start of the change and the traveling direction after the end of the change. It was decided to determine whether or not the direction change was performed. In other words, when the vehicle changes direction, the direction of travel before the start of direction change and the direction of travel after the end of direction change are almost reversed as a result, regardless of how the direction of travel of the vehicle changes during the process. Direction. Therefore, as in the vehicle navigation device according to claim 1, it is possible to easily determine whether or not the vehicle has changed its direction by using the traveling direction before the start of the change in the traveling direction of the vehicle and the traveling direction after the end of the change. In addition, it can be determined with high accuracy.

  Then, when it is determined by the direction change determination means that the vehicle has changed direction, the map matching means determines that the road on which the vehicle was traveling before the change in traveling direction is the road on which the vehicle is traveling. Thus, the vehicle mark can be displayed immediately on the road on which the vehicle is traveling.

  According to a second aspect of the present invention, the direction change determination means has a dead zone area for distinguishing whether or not data relating to the traveling direction is accepted with reference to at least one of a change start position and a change end position of the traveling direction of the vehicle. Set the direction of travel when the vehicle enters the dead zone area as the direction of travel before the start of change, and the direction of travel when the vehicle exits the dead zone as the direction of travel after the end of change. Based on this, it can be determined whether or not the vehicle has changed direction.

  That is, when the position of the vehicle belongs to the dead zone area, the traveling direction at that position is not used for the direction change judgment, and the traveling direction at the time of entering and leaving the dead zone area is the direction change. It is used for judgment. In this case, by comparing the dead zone area and the vehicle position, the approach position and the exit position to the dead zone area can be specified, and the traveling direction at each position can be easily extracted.

  According to a third aspect of the present invention, the direction change determination unit includes a storage unit that stores a history of the traveling direction of the vehicle. When the vehicle changes its traveling direction, the traveling direction stored in the storage unit The direction of travel before the start of the direction change and the direction of travel after the end of the change in the direction of travel are extracted, and based on these travel directions, it is determined whether or not the vehicle has changed direction. May be. Even in this case, it is possible to easily extract the traveling direction before the start of the traveling direction change and the traveling direction after the end of the change and easily determine whether or not the vehicle has changed direction.

  In addition, as described in claim 4, the direction change determination means, when the traveling direction before the start of change and the traveling direction after the end of the change belong to a predetermined angle range that can be regarded as the reverse direction, It is preferable to determine that the vehicle has changed direction. When the road is composed of a plurality of lanes on one side, even if the vehicle changes direction, the traveling direction is not always reverse by exactly 180 °. Therefore, it is preferable to determine that the direction has been changed on condition that the traveling direction before the start of the change and the traveling direction after the end of the change belong to a predetermined angle range that can be regarded as the reverse direction.

  According to a fifth aspect of the present invention, the direction change determination unit may determine that the map matching unit cannot determine the road on which the vehicle is traveling as one condition for determining that the vehicle has changed direction.

  Since the opposite lanes of the same road are basically indicated by the same road data, the opposite lanes are not connected by the road data. For this reason, when the vehicle changes its direction, the map matching means normally searches for a road that should match the current position of the vehicle, and the vehicle is running during the search for such a road. The road cannot be determined. Therefore, by determining that the map matching means cannot determine the road on which the vehicle is traveling as one condition for determining that the vehicle has changed direction, it is possible to improve the determination accuracy of the change of direction.

  Hereinafter, a vehicle navigation apparatus according to an 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 vehicle navigation apparatus according to this embodiment.

  As shown in the figure, the car navigation device of this embodiment includes a position detector 1, a map data input device 6, an operation switch group 7, a control circuit 8 connected thereto, and an external memory connected to the control circuit 8. 9. A display device 10 and an external information input / output device 11 are provided.

  The control circuit 8 is configured as a normal computer, and includes a well-known CPU, ROM, RAM, I / O, and a bus line for connecting these configurations. In the ROM, a program to be executed by the control circuit 8 is written, and a CPU or the like executes predetermined arithmetic processing according to this program.

  The position detector 1 includes a known geomagnetic sensor 2, a gyroscope 3, a distance sensor 4, and a GPS receiver 5 for GPS (Global Positioning System) that measures the position of a vehicle based on radio waves from a satellite. Have. Since these have errors of different properties, they are configured to be used while being complemented by a plurality of sensors. That is, data (current position coordinates and traveling direction) relating to the current position of the vehicle is measured by hybrid navigation that combines radio wave navigation by GPS and self-contained navigation by the geomagnetic sensor, gyroscope 3 and distance sensor 4. Depending on the accuracy of each sensor, the position detector 1 may be configured as a part of the above-described ones, and a steering rotation sensor (not shown), a vehicle speed sensor for each rolling wheel, or the like may be used.

  The map data input device 6 is a device for inputting map data including road data, background data, and character data. As a storage medium for storing the map data, a CD-ROM or a DVD-ROM is generally used because of the amount of data, but a memory card, a hard disk, or the like may be used.

  Further, the map data can be acquired from an external server by communication and stored in an external memory 9 described later. In this case, using the map data stored in the external memory 9, various navigation functions such as displaying a map around the vehicle, changing the scale of the displayed map, and route guidance can be performed. These functions are executed mainly by performing various arithmetic processes by the control circuit 8.

  Here, an example of the structure of the road data will be described with reference to FIG. As shown in FIG. 2, the road data 6a includes a link ID with a unique number for each road, link coordinate data, node coordinate data, road type data indicating a road type such as an expressway or a national road, road width data, etc. It consists of each data. The link in the road data 6a is obtained by dividing each road on the map into a plurality of nodes by nodes indicating intersections, branch points, etc., and defining the link between the two nodes. The link coordinate data describes the start and end coordinates of this link. When a node is included in the middle of the link, the node coordinates are described in the node coordinate data. The road data 6a is used not only to display a map but also to give the shape of a road when performing map matching processing, or to search for a guide route to a destination. However, regarding the search for the guide route, road network data indicating the connection relationship of each road to be used as the guide route may be separately prepared and searched using the network data.

  Although not shown, the background data is configured as data in which each facility, topography, and the like on the map are associated with the corresponding coordinates on the map. Regarding the facility, data such as a telephone number and an address are also stored in association with the facility. This mark data may be stored in the external memory 9 described later. The character data is used to display place names, facility names, road names, and the like on a map, and is stored in association with coordinate data corresponding to the positions to be displayed.

  As described above, each road is basically represented by a single link. Therefore, conventionally, when the vehicle has made a turn (U-turn), the map matching process may not be able to immediately match the position of the vehicle on the road on which the U-turn has been made. As described above, the map matching process determines the road on which the vehicle is traveling based on the degree of coincidence between the connected link shape and the shape of the traveling locus of the vehicle. This is because the opposite lanes are not connected via a link.

  As the operation switch group 7, for example, a touch switch or a mechanical switch integrated with the display device 10 described later is used, and is used for various inputs. For example, it is possible to input the position of the destination using the operation switch group 7, and in this case, the navigation device automatically selects the optimum route from the current position to the destination and guides the route. Is provided with a so-called route guidance function. As a method for automatically setting an optimum route, a known method such as the Dijkstra method is known. Further, for example, it is possible to input an address, a facility name, a telephone number, etc. of a desired facility using the operation switch group 7, and in this case, the navigation device searches for the location of the facility by the input. It also has a search function.

  The external memory 9 includes a storage medium such as a memory card or a hard disk. The external memory 9 stores various data such as text data, image data, and audio data stored by the user. Further, as described above, when the vehicle navigation apparatus acquires map data from an external server, the map data is stored.

  The display device 10 is configured by, for example, a liquid crystal display, and is input to the screen of the display device 10 from the host vehicle mark that displays the traveling direction while corresponding to the current position of the vehicle and the map data input device 6. A road map around the vehicle generated by the map data can be displayed. Furthermore, when a destination is set, a guidance route from the current position to the destination can be displayed on the road map in an overlapping manner.

  The external information input / output device 11 receives information such as road traffic information distributed from the VICS center via beacons laid on the road and FM broadcast stations in various places, or from the vehicle side to the outside as necessary. It is a device that transmits information. The received information is processed by the control circuit 8. For example, traffic jam information, regulation information, and the like are displayed on the road map displayed on the display device 10.

  Next, a process of displaying the host vehicle mark indicating the current position and traveling direction of the vehicle and the surrounding road map on the display device 10 while performing the map matching process, which is a feature of the present invention, will be described with reference to FIGS. It demonstrates using the flowchart of these. 3 shows a main routine for determining a road on which the vehicle travels using map matching processing and displaying the vehicle mark on the road, and FIG. 4 shows map matching in the flowchart of FIG. Details of the processing are shown. Moreover, the process shown in FIG.3 and FIG.4 is repeatedly performed, for example, whenever predetermined time passes, or whenever a vehicle travels a predetermined distance.

  As shown in FIG. 3, first, in step S10, signals from each sensor of the position detector 1 are input, and in step S20, the current position of the vehicle is calculated based on the input signals. At this time, the position data by the GPS receiver 5 is acquired in the same form as the coordinate data (latitude and longitude) of the road data described above. Further, the geomagnetic sensor 2, the gyroscope 3, and the distance sensor 4 acquire data related to the traveling direction and travel distance of the host vehicle, and calculate the coordinate data of the current position based on the vehicle position calculated or determined in the past. Perform (calculation of coordinate data by self-contained navigation). The current position is basically obtained based on coordinate data calculated by self-contained navigation. However, when the position data by the GPS receiver 5 is acquired, the two are compared, and when the difference is not less than a predetermined distance, the position data by the GPS receiver 5 is adopted as the current position.

  Subsequently, in step S30, map data around the vehicle is read based on the coordinates of the current position of the vehicle calculated in step S20. Next, in step S40, map matching processing is performed. In this map matching process, as will be described in detail later, for example, a road within a predetermined distance from the current position calculated in step S20, or a road connected to the matching road if already matched on the road Is identified as a road on which the vehicle may travel. In step S10, a plurality of current positions calculated in the past and the latest current position are connected to calculate the shape data of the travel locus. The shape data of the travel locus is compared with the shape of the road on which the vehicle may travel, and the road with the highest correlation is determined (estimated) as the road on which the vehicle is traveling.

  The calculation of the current position in step S20 and the calculation of the travel locus described above may be performed only from the position data of the GPS receiver 5, or may be performed only from the position data of the self-contained navigation.

  When the road on which the vehicle is traveling is determined by the map matching process, the current position of the vehicle is determined by applying the shape of the traveling locus described above to the road in step S50. As described above, when the current position of the vehicle is determined, position data by self-contained navigation is calculated with reference to the determined position. In step S60, display data for displaying a surrounding road map is generated while displaying a vehicle mark indicating the traveling direction of the vehicle at a position corresponding to the determined current position, and the display data is displayed. Is used to display the vehicle mark and the surrounding road map on the display device 10.

  Next, the details of the map matching process will be described based on the flowchart of FIG. First, in step S110, travel locus data including position and direction data is updated based on the current position calculated in step S20. In step S120, it is determined whether or not a change in the traveling direction of the vehicle has started based on the updated travel locus data. In this determination process, if it is determined that a change in the traveling direction of the vehicle has started, a dead zone area is set in step S130 with reference to the starting point of the traveling direction change. For example, as shown in FIGS. 5 (a) and 5 (b), this dead zone area includes a travel locus at the time of the U-turn when the vehicle makes a U-turn from the starting direction change start point. It is set around the starting point of the traveling direction change.

  In step S140, it is determined whether or not the change in the traveling direction of the vehicle has ended based on the updated travel locus data. In this determination process, when it is determined that the change in the traveling direction of the vehicle has ended, in step S150, the traveling direction data of the vehicle at the entry position to the dead zone area and the traveling direction data of the vehicle at the exit position from the dead zone area. Is extracted from the travel locus data. As the traveling direction data at the dead zone entry position and the leaving position, one traveling direction data respectively corresponding to the approach position and the exit position may be used, or corresponding to a plurality of positions before and after the entry. The traveling direction data obtained by averaging a plurality of traveling direction data may be used.

  In step S160, it is determined whether or not the vehicle has made a U-turn based on the traveling direction data at the dead zone entry position and the exit position extracted in step S150. Specifically, based on whether the traveling direction at the approach position and the traveling direction at the exit position can be regarded as opposite directions, for example, whether the vehicle belongs to an angle range of 180 ° ± 30 °, the vehicle makes a U-turn. Determine whether or not.

  When the vehicle makes a U-turn, as shown in FIG. 5 (a), the cumulative value of the change in the traveling direction of the vehicle greatly exceeds 180 °, or as shown in FIG. 5 (b), the traveling direction of the vehicle There are various driving miracles of the vehicle during the U-turn process.

  However, regardless of how the traveling direction of the vehicle changes during the U-turn process, when the vehicle makes a U-turn, the traveling direction before the U-turn starts and the traveling direction after the U-turn ends As a result, the reverse direction is obtained. Therefore, as in this embodiment, by using the traveling direction data at the dead zone entry position and the leaving position, the traveling direction before the vehicle starts changing the traveling direction and the traveling after the traveling direction change ends. The direction can be compared, and it can be determined easily and accurately whether the vehicle has made a U-turn.

  If it is determined in step S160 that the vehicle has made a U-turn, in step S180, the road on which the vehicle was traveling before entering the dead zone area, that is, the road on which the vehicle was traveling before the direction of travel was changed, It is determined that the road is where the vehicle is traveling. Therefore, by executing the processing of steps S50 and S60 in the flowchart of FIG. 3 based on this determination, even if the vehicle makes a U-turn, the vehicle mark is immediately correctly displayed on the road. Can be displayed.

  On the other hand, if it is determined in step S160 that the vehicle has not made a U-turn, a normal map matching process including steps S170, S190, and S200 is executed. That is, in step S170, the shape data of the travel locus of the vehicle is calculated based on the travel locus data updated in step S10, and the calculated shape data is compared with the road data. This road data is road data of a candidate road such as a road within a predetermined distance from the current position of the vehicle, or a road connected to the matching road if the current position of the vehicle is already matched on the road. is there.

  In this comparison processing, road data having a road shape having the highest correlation value with respect to the shape data of the travel locus is selected from the road data of the candidate roads. This correlation value is the length of the distance between the current position of the vehicle and the road, the direction and angle when the vehicle turns right and left, the straight distance before and after the right and left turn points, It is calculated in consideration of a plurality of factors that characterize the shape of the travel locus, such as the straight-ahead distance between right and left turns, and the number and order of the right and left turns.

  In step S190, it is determined whether or not the correlation value calculated in step S170 is greater than or equal to a predetermined threshold value. If the correlation value is determined to be less than the predetermined threshold value in this determination process, there is no road that can be reliably determined that the vehicle is traveling among the candidate roads. finish. In this case, in the display process of step S60 of the flowchart of FIG. 3, the surrounding road map is displayed while displaying the own vehicle mark in the position corresponding to the current position calculated in step S20 according to the acquired or calculated traveling direction. Display together. That is, in this case, the current position of the vehicle is not matched on the road, and the current position is used as it is as a position to display the own vehicle mark.

  As described above, according to the vehicle navigation device according to the present embodiment, whether or not the vehicle has made a U-turn based on the traveling direction before the start of the change in the traveling direction of the vehicle and the traveling direction after the end of the change in the traveling direction. Therefore, the determination can be performed easily and accurately.

  In particular, in the present embodiment, the dead zone area is set based on the starting point of change in the traveling direction. When the position of the vehicle belongs to this dead zone area, the traveling direction at that position is not used for determining whether or not a U-turn has been made, and the traveling direction at the time of entering and leaving the dead zone is U. It is used for turn judgment. That is, by setting the dead zone area, it is possible to specify the approach position and the exit position to the dead zone area simply by comparing the dead zone area and the vehicle position, and it is possible to easily extract the traveling direction at each position.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the dead zone area is set when the change in the traveling direction of the vehicle is started, but the dead zone area is set when the change in the traveling direction of the vehicle is finished, You may make it compare each position in the dead zone area and driving | running | working miracle data.

  In addition to setting the moving direction change start point as a reference, the dead zone area is set using the moving direction change end point as a reference or, for example, an intermediate position on a line connecting the change start point and the change end point as a reference. For example, it may be set based on both the change start point and the change end point.

  In addition, the dead zone area is not set as in the above-described embodiment, but the traveling direction before the start of the traveling direction change and the traveling direction after the end of the change are extracted directly from the travel locus data. Is also possible. That is, since the travel locus data includes a position and a direction, data corresponding to the change start point and the change end point in the traveling direction can be specified from the magnitude of the change in the direction of each position. Therefore, the traveling direction before the change start point and after the change end can be obtained from the travel locus data.

  Further, the map matching process shown in the flowchart of FIG. 4 may be modified as shown in FIG. In the flowchart shown in FIG. 6, first, a normal map matching process is executed (steps S210 to S240). Then, in this normal map matching process, when the road on which the vehicle is traveling cannot be determined among the candidate roads (when “No” is determined in step S230), U shown in steps S25 to S270. Turn determination is performed. In other words, in the flowchart shown in FIG. 6, one condition for determining that the vehicle has made a U-turn is that the road on which the vehicle is traveling cannot be determined by the normal map matching process.

  As described above, the opposite lanes on the same road are basically indicated by the same link data, so the opposite lanes are not connected by the link data. For this reason, when the vehicle makes a U-turn, in a normal map matching process, the road on which the vehicle mark is to be displayed is temporarily lost and a new road is searched. Accordingly, the road on which the vehicle is traveling cannot be determined by the normal map matching process, that is, the fact that the vehicle is being searched is set as one condition for determining that the vehicle has made a U-turn, thereby improving the U-turn determination accuracy. be able to.

1 is a block diagram showing a schematic configuration of a vehicle navigation device according to an embodiment of the present invention. It is explanatory drawing which shows the data structure of the road data in a map data input device. It is a flowchart which shows the main routine for determining the road where a vehicle drive | works using a map matching process, and displaying the own vehicle mark on the road It is a flowchart which shows the detail of the map matching process in the flowchart of FIG. (A), (b) is explanatory drawing which each shows the example of the driving | running | working locus | trajectory in the U-turn process, when a vehicle actually makes a U-turn. It is a flowchart which shows the detail of the map matching process by the modification of this invention. (A), (b) and (c) is explanatory drawing for demonstrating the principle of a map matching process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Position detector 2 Geomagnetic sensor 3 Gyroscope 4 Distance sensor 5 GPS receiver 6 Map data input device 7 Operation switch group 8 Control circuit 9 External memory 10 Display device 11 External information input / output device

Claims (5)

A display unit for displaying at least a vehicle mark indicating a current position and a traveling direction of the vehicle and a map around the vehicle mark;
Measuring means for measuring a current position and a traveling direction of the vehicle;
A travel locus calculating means for calculating a travel locus of the vehicle based on the current position measured by the measuring means;
Map data storage means for storing map data;
By comparing the shape of the road near the current position of the vehicle in the map data stored by the map data storage means with the shape of the travel locus calculated by the travel locus calculation means, the road on which the vehicle is traveling is determined. Map matching means for executing map matching processing to be determined;
A vehicle navigation apparatus comprising display control means for displaying the vehicle mark and a surrounding map on the display unit so that the vehicle mark is located on a road determined by the map matching means,
When the traveling direction of the vehicle changes, the vehicle includes a direction change determination unit that determines whether the vehicle has changed direction based on the direction of travel before the start of the change and the direction of travel after the end of the change,
The map matching means determines that the road on which the vehicle was traveling before the change in traveling direction is determined as the road on which the vehicle is traveling when the direction change determining means determines that the vehicle has changed direction. A vehicle navigation apparatus characterized by the above.   The direction change determination means sets a dead zone area for distinguishing whether or not data relating to the traveling direction is accepted with reference to at least one of a change start position and a change end position of the traveling direction of the vehicle, and the dead zone area Based on these traveling directions, the traveling direction when the vehicle enters is the traveling direction before the start of the change, and the traveling direction when the vehicle leaves the dead zone area is the traveling direction after the end of the change, The vehicle navigation apparatus according to claim 1, wherein it is determined whether or not the vehicle has changed direction. The direction change determination means includes storage means for storing a history of the traveling direction of the vehicle,
When the vehicle changes its traveling direction, the traveling direction stored in the storage means before starting the change of the traveling direction and the traveling direction after finishing the traveling direction change are extracted, and these The vehicle navigation apparatus according to claim 1, wherein it is determined whether or not the vehicle has changed direction based on a traveling direction of the vehicle.   The direction change determination means determines that the vehicle has changed direction when the traveling direction before the start of the change and the traveling direction after the end of the change belong to a predetermined angle range that can be regarded as opposite directions. The vehicle navigation device according to any one of claims 1 to 3, wherein the determination is made.   2. The direction change determination unit according to claim 1, wherein the map matching unit cannot determine a road on which the vehicle is traveling as one condition for determining that the vehicle has changed direction. Item 5. The vehicle navigation device according to any one of Item 4.

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