JP7140459B2 - Map matching method and electronic device - Google Patents

Description

TECHNICAL FIELD The present invention relates to electronic devices with navigation functions, and more particularly to map matching methods.

The navigation system accurately displays the vehicle position on the road by map-matching the vehicle position on the link. For example, the map matching method of Patent Document 1 prepares a number of virtual links corresponding to the width of the road or the number of lanes on the road, performs map matching on the virtual links as target links for map matching, and selects the most suitable virtual link among them. and correct the vehicle position on the road according to the optimum virtual link. The navigation device of Patent Document 2 sets a plurality of virtual links at the time when the vehicle enters the tollgate area, and performs map matching on the virtual links. The map matching method of Patent Document 3 generates a virtual link corresponding to the shape of a road for a target link that is a candidate for map matching, and performs map matching based on the position and direction of the virtual link.

Japanese Patent Application Laid-Open No. 2004-226341 JP 2006-250875 A Japanese Unexamined Patent Application Publication No. 2017-3462

Next, an example of erroneous map matching of a toll gate area in a conventional on-vehicle device will be described. As shown in FIG. 1A, a side road 12 branches off from a main line 10 of an expressway, and the side road 12 is connected to the entrance side of a toll gate (ETC gate) 20 . A side road 14 is further connected to the exit side of the tollgate 20, and the side road 14 is connected to another road 16 such as a general road or a toll road. The tollbooth 20 typically supports multiple lanes so that multiple vehicles can enter at the same time. Sideways 12 and 14 are therefore widened at the portion where they connect to tollgate 20 .

FIG. 1(B) shows links on the road map database corresponding to the roads in FIG. 1(A). The links for the main highway 10 are L1, L2, the link for the side road 12 is L3, the link for the side road 14 is L4, and the link for the other road 16 is L5. A branch point of the link L1 is the node N1, one end of the link L3 is connected to the node N1, and the other end is connected to the node N2 at the center of the lane of the toll booth 20. FIG. One end of link L4 is connected to node N2, and the other end is connected to link L5 via node N3.

On the road map database, the link L3 of the side road 12 leading to the toll gate 20 is drawn so as to pass through the approximate center of the side road 12 . As shown in the figure, if the toll gate 20 has seven lanes, the road width of the side road 12 is widened accordingly, the node N2 is set at the center of the lane, and the link L3 is placed substantially at the center of the side road 12. be killed.

When the main line 10 runs parallel to the side road 12 to some extent, and the own vehicle M getting off the side road 12 from the main line 10 runs in the right lane of the side road 12 (that is, when it runs closer to the main line 10). , the vehicle position M is closer to the link L2 of the main road 10 than the link L3 of the side road 12, and the vehicle position M is erroneously map-matched to the main road 10 even though it is getting off the main road 10. - 特許庁As a result, there is a problem that the position of the vehicle is shifted, and the position of the vehicle is displayed on a different road on the road screen of the in-vehicle device.

FIG. 2(A) is an example of display during route guidance to a destination. The initial route R to the destination is to get off the main line 10 and pass through the A toll gate from the side road 12. When the vehicle position M approaches the branch of the main line 10, the A toll gate (ETC gate) is passed. Enlarged display and voice guidance to the effect that it will pass are performed. However, as described above, if the vehicle position M is erroneously mapped to the main road 10 even though the vehicle has exited the main road 10, the in-vehicle device detects that the vehicle is on the main road 10 as shown in FIG. 2(B). erroneously recognizes that it did not get off, and performs reroute processing to search for another route R1 to the destination.

SUMMARY OF THE INVENTION An object of the present invention is to provide a map matching method and an electronic device that solve the problems of the prior art and improve the map matching accuracy.

The map matching method according to the present invention is for attracting and processing the detected vehicle position to a link, acquiring lane information of a specific area connected to a road branched from another road, and acquiring the acquired lane information. based on the position of the link of the branched road is corrected in the direction of approaching the other road, and map matching is performed using the corrected link as a candidate link.

In one embodiment, the branched road link is corrected by a distance according to the number of lanes. In one embodiment, one end of the branched road link is connected to the specific area, the other end is connected to the other road, and the position of the one end is shifted. In one embodiment, one end of the forked road link is shifted from a lane center position in a particular area to a position closer to the other road. In one embodiment, the bifurcated road link is corrected according to the shape of the other road. In one embodiment, one end of the branched road link is connected to the entrance side of the specific area, the other end is connected to the first node of the other road, and the exit side of the specific area. is connected to a second node of another road, the forked road link and the exit road link connect the first node and the second node It is corrected to a link that connects with a straight line. In one embodiment, the specified area is a toll booth for a toll road.

An electronic device having a navigation function according to the present invention includes detection means for detecting a vehicle position and means for map-matching the detected vehicle position to a link. acquires lane information of a specific area connected to the road branched from, corrects the position of the link of the branched road based on the acquired lane information in the direction of approaching the other road, and corrects the Map matching is performed using the links obtained as candidate links.

According to the present invention, the link position of the branched road is corrected in the direction of approaching the other road, and the corrected link is used for map matching. This makes it easier to map-match to the link that has been selected, and suppresses erroneous map-matching to other roads. As a result, the position of the vehicle can be accurately displayed on the road, and unnecessary reroute due to incorrect map matching can be avoided.

FIG. 10 is a diagram illustrating an example in which erroneous map matching occurs in a toll gate area in a conventional on-vehicle device; FIG. 2A shows an example of route guidance to the original destination, and FIG. 2B shows an example of reroute by map matching. It is a figure which shows the structure of the vehicle-mounted apparatus based on the Example of this invention. It is a figure which shows the structure of the map matching function based on the Example of this invention. It is a flow explaining operation|movement of the map matching function based on the Example of this invention. It is a figure explaining the correction method of the side road link based on the Example of this invention. 4 is a table that defines the relationship between the number of lanes of a toll booth and the amount of shift according to the embodiment of the present invention; It is a figure explaining the correction method of the side road link based on the modification of this invention.

Next, an embodiment of the invention will be described. The electronic device equipped with the navigation function according to the present invention can be a computer device, a high-performance mobile phone terminal represented by a smart phone, a portable terminal, or an in-vehicle device equipped with navigation/audio/visual functions. In the following embodiments, an in-vehicle device equipped with a navigation function is exemplified.

FIG. 3 is a block diagram showing the internal configuration of the in-vehicle device 100 of this embodiment. In-vehicle device 100 includes input unit 110 , position detection unit 120 , navigation unit 130 , communication unit 140 , display unit 150 , audio output unit 160 , storage unit 170 and control unit 180 . However, the configuration shown here is only an example, and the in-vehicle device 100 includes other functions such as an audio/visual function, a television/radio broadcast receiving function, a function of displaying images from an in-vehicle camera, and the like. may

The input unit 110 includes an input key device, a voice input recognition device, a touch panel, etc., receives instructions from the user via these devices, and provides them to the control unit 180 . The position detection unit 120 detects the current position of the vehicle using GPS signals transmitted from GPS satellites and/or a direction sensor such as a gyro sensor. The position detection unit 120 provides the detected vehicle position to the control unit 180 and the navigation unit 130 .

The navigation unit 130 has a function of map-matching the vehicle position detected by the position detection unit 120 on a link of road map data. Further, when a destination or waypoint is set via the input unit 110, the navigation unit 130 searches for a route from the position of the vehicle to the destination, and displays the searched route guidance on the display unit 150 or the voice output unit. Output from 160.

The communication unit 140 enables wireless communication with external devices and networks. The in-vehicle device 100 can, for example, request map distribution from a map routing server and download a map of the vehicle's surroundings from there.

The storage unit 170 stores road map data used by the navigation unit 130, and stores data, application software, and the like necessary for the in-vehicle device 100. FIG. Road map data includes link data, node data, facility data, and the like. The link data includes a link ID that identifies a link, a node ID that identifies a node to which the link is connected, lane information (including the number of lanes), road type information (expressway, side road leading to a toll gate, general road, national road, etc.). etc.). The node data includes a node ID for identifying a node, latitude and longitude of the node, connection link ID to which the node is connected, intersection information, and the like.

In this embodiment, map matching also has a function of automatically correcting the link position of a side road belonging to a specific area. The specific areas are, for example, toll gates on expressways, parking areas, service areas, etc. These specific areas are connected to side roads that branch off from the main road. The information necessary to correct the link position of the side road is the identification information of the specific area, the coordinates of the specific area, the number of lanes that can enter the specific area at the same time, and the link that identifies the side road connected to the specific area. ID, node ID (including coordinates) connecting side road links in a specific area, and the like. Information about these specific areas may be stored in node data or facility data, for example.

The control unit 180 controls operations of each unit of the in-vehicle device 100 . In one embodiment, control unit 180 includes a microprocessor or microcontroller with ROM/RAM or the like, in which programs for controlling each unit are stored. In this embodiment, the control unit 180 executes a program for controlling the navigation unit 130. Details of the map matching function of the navigation unit 130 will be described here.

In map matching, the vehicle position detected by the position detection unit 120 is processed by attracting it to the link, and the detected vehicle position is corrected. For example, as disclosed in Patent Document 1, map matching finds an optimum link from the vertical distance from the vehicle position to the link, the difference between the relative bearing of the vehicle and the link bearing, etc. Map mapping the car position.

In this embodiment, when getting off the main road and advancing from a side road to a specific area on an expressway or the like, the link position of the side road is virtually shifted to the side of the main road to suppress erroneous map matching to the main road. The specific area is, for example, a tollgate, a service area, a parking area, etc. In the following description, a tollgate is used as an example of the specific area.

FIG. 4 is a block diagram showing the configuration of the map matching function of this embodiment. The map matching function 200 includes a vehicle position acquisition unit 210 that acquires the vehicle position detected by the position detection unit 120, and a toll gate search that refers to road map data and searches for toll gates of toll roads such as expressways. A lane information extraction unit 230 for extracting the lane information of the retrieved toll gate or the lane information of the side road connected to the toll gate, and a side road link for correcting the link position of the side road based on the extracted lane information. A correction unit 240 and a link correction cancellation unit 250 for canceling the position correction of the side road link when the vehicle has passed through the toll gate or the vehicle position has left the toll gate by a predetermined distance or more.

Next, FIG. 5 shows the operation flow of map matching according to this embodiment. When the navigation unit 130 is operated and the vehicle starts traveling (S100), the position detection unit 120 detects the vehicle position, and the vehicle position acquisition unit 210 detects the vehicle position. The map matching function performs map matching processing between the detected vehicle position and the link, and a mark indicating the vehicle position is superimposed on the road on which the vehicle is traveling and displayed on the road screen of the display unit 150 .

The toll gate search unit 220 determines whether or not the vehicle is traveling on a toll road (S102). The tollgate search unit 220 refers to the link data of the link for which the vehicle position is map-matched, and determines whether the road type indicates a toll road. When the toll gate search unit 220 determines that the vehicle is traveling on a toll road, it searches for a toll gate within a certain range from the vehicle position (S104). For example, a search is made for tollgates having position coordinates within a certain range from the position of the vehicle.

After the toll gate is searched by the toll gate search unit 220, the lane information of the toll gate is extracted by the lane information extraction unit 230 (S106). The lane information may be extracted from the attribute data of the tollgate, or may be extracted from the link data of the side roads connected to the tollgate.

After the lane information is extracted, the side road link correction unit 240 corrects the position of the side road link connected to the tollgate based on the lane information (S108). This link position correction is temporary or pseudo processing to prevent the vehicle from being erroneously mapped to the main road when the vehicle exits the main road and heads for the toll gate from the side road. The correction information of the side road link is stored in the storage unit 170 or a register, and the position-corrected side road link is used as a candidate link for map matching.

A method of correcting the position of the side road link will be described with reference to FIG. The links shown in FIG. 6(A) correspond to the road environment shown in FIG. 1(A) and show the default state in which the positions of the side road links are not corrected. Links L1 and L2 are the main line of the expressway, and L3 is a side road branching from the main line to the toll gate. One end of link L3 is connected to node N1, which is a branch point of link L1, and the other end is connected to node N2, which is the central position of multiple lanes (here, seven lanes) of toll gate 20. FIG. Link L4 is a side road on the exit side of toll gate 20, one end of link L4 is connected to node N2, and the other end is connected to node N3 that joins link L5 of another road.

As shown in FIG. 6B, the side road link correction unit 240 shifts the position of the side road link L3 in the direction of approaching the link L2 of the main line of the expressway according to the number of lanes of the toll gate 20 . Specifically, the coordinates (X1, Y1) of the node N2 of the toll gate 20 are changed to the coordinates (X1, Y2) of the node N2A so as to move closer to the main road side by the shift amount D1, and the nodes N1 and N2A are connected. A side road link L3A is virtually created. In this case, since the X coordinate does not change, the shift amount D1 is represented by |Y1−Y2|, but the coordinates of the node N2A may be changed to (X2, Y2) to change the position of the X coordinate. . Similarly, the side road link 4 may be shifted to the side road link 4A connecting the node N2A and the node N3. However, the shift of the side road link 4 is not essential.

The example shown in FIG. 6(C) is a shift example in which the number of lanes of the toll gate 20 is 11, which is greater than the number of lanes of 7 lanes of the toll gate 20 shown in FIG. 6(B). The coordinates (X1, Y1) of the node N2 at the lane center position of the toll gate 20 are changed to the coordinates (X1, Y3) of the node N2B so as to approach the main road side by the shift amount D2, and the node N1 and the node N2B are connected. Road link L4B is created virtually. The shift amount D2 has a size proportional to the number of lanes and is set larger than the shift amount D1. When the number of lanes of the toll gate 20 increases, the distance between the side road link L3 and the main line link L2 increases, and when traveling on the right side of the side road, the map matching with the main line link L2 becomes easier. In order to suppress this, when the number of lanes increases, the side road link is shifted to the main line side according to the number of lanes, making it easier for vehicles traveling on the right side of the side road to be map-matched with the side road link. .

The relationship between the number of lanes Ln of the tollgate and the shift amount is defined in advance in a table such as that shown in FIG. can be determined (D0<D1<D2<D3). The side road link correction unit 240 adjusts the side road links closer to the main road side, for example, when the X coordinate is not changed, the node A node N2A and a node N2B are obtained by converting the Y coordinate of N2, and side road links L3A and L3B are created.

The side road link whose position has been corrected by the side road link correction unit 240 is used as a candidate link for map matching when the vehicle passes through the vicinity of the tollgate (S110). If the vehicle gets off the main road and drives on the right side of the side road near the main road, the corrected side road link is used as a candidate link for map matching, so the vehicle position is closer to the side road than the main road link. Map-matching to the link is facilitated, and erroneous map-matching to the main line is suppressed. When the vehicle position is map-matched with the corrected side road link, it is determined that the vehicle position is traveling on the side road, and the vehicle position mark is displayed on the road map screen of the display unit 150 on the side road. to be displayed. Also, reroute processing is avoided when a route through a side road is being searched for.

The link correction canceling unit 250 cancels the correction of the side road link (S114) when the own vehicle passes through the tollgate or when the own vehicle is separated from the tollgate by a certain distance or more (S112). That is, the side road link returns to the state shown in FIG. 6(A).

As described above, according to this embodiment, the side road link that branches off from the main line and heads for the toll gate is shifted to the main line side according to the number of lanes of the toll gate. When traveling on a road, the vehicle position is easily map-matched to the side road link, and erroneous map-matching to the main line is suppressed. As a result, the vehicle position mark can be accurately displayed on the road screen of the display unit 150, and unnecessary reroute processing due to incorrect map matching can be avoided.

Next, a modified example of this embodiment will be described. In the above embodiment, when correcting the position of the side road link, the coordinates of the node of the toll gate to which the side road link is connected are changed. Links L3 and L4 are converted into one side road link L3C. Specifically, a virtual link L3C is created by connecting the node N1, in which the side road link L3 is connected to the link L1 of the main road, and the node N3, in which the side road link L4 is connected to the link L5 of another road, with a straight line. do. If the node N3 is located closer to the main road than the node N2, the virtual link L3C is shifted closer to the main road than the original side road link L3, and the same effect as in the above embodiment can be expected.

As another modification, the shape and orientation of the side road link may be corrected in accordance with the shape and orientation of the main line link L2, which is likely to be incorrectly map-matched. Information such as the shape or orientation of the link can be included in the link data. Therefore, when correcting the side road link, the side road link correction unit 240 refers to the link data of the main road where the side road diverges, and adjusts the position of the side road link to the main road side in consideration of the shape and direction of the main road. It shifts and corrects its shape and orientation. For example, when the absolute or relative bearing of the link L2 of the main line is θa, the coordinates (latitude , longitude) is changed. As a result, the position of the vehicle traveling from the main road to the side road can be easily map-matched with the side road link.

In the above embodiment, an example of a toll gate connected to the main line of an expressway via a side road has been described, but the present invention is not limited to this, and parking lots, parking areas, and service areas branched from the main line. It can also be applied to map matching of side roads leading to specific areas such as. In this case as well, lane information for entering a parking lot, parking area, service area, etc., is obtained from road map data, etc., and the position of the side road link is corrected so that the side road link approaches the main line link.

Furthermore, in the above embodiment, the side road links stored in the road map database are temporarily corrected, but in addition to this, a road map database in which the side road links are permanently corrected is used. may

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to specific embodiments, and various modifications, Change is possible.

100: In-vehicle device 110: Input unit 120: Position detection unit 130: Navigation unit 140: Communication unit 150: Display unit 160: Audio output unit 170: Storage unit 180: Control unit R, R1: Route M: Own vehicle position

Claims (8)

A map matching method performed in an electronic device with navigation capabilities, the map matching method attracting and processing a detected vehicle position to a link , the map matching method further comprising:
obtaining lane information for a specific area connected to a road branched from another road ;
correcting the position of the link of the branched road in a direction approaching the other road based on the acquired lane information ;
A map matching method , comprising map matching using the corrected link as a candidate link. 2. The map matching method according to claim 1, wherein the branched road link is corrected by a distance corresponding to the number of lanes. 3. The method according to claim 1, wherein one end of said branched road link is connected to a specific area, the other end is connected to said other road, and the position of said one end is shifted. Described map matching method. 4. The map matching method according to claim 3, wherein one end of the branched road link is shifted from a lane center position in the specific area to a position closer to the other road. 5. The map matching method according to any one of claims 1 to 4, wherein the branched road link is corrected according to the shape of the other road. One end of the branched road link is connected to the entrance side of the specific area, the other end is connected to the first node of the other road, and the road link on the exit side of the specific area is connected to the first node of the other road. When connected to a second node of another road, the link of the branched road and the link of the road on the exit side become a link connecting the first node and the second node with a straight line. 2. The map matching method of claim 1, wherein the map matching method is compensated. 7. The map matching method according to any one of claims 1 to 6, wherein the specific area is a toll booth of a toll road. An electronic device with navigation capabilities,
a detection means for detecting the vehicle position;
and means for map-matching the detected vehicle position to the link,
The map matching means includes:
Acquiring lane information of a specific area connected to a road branched from another road, correcting the position of the link of the branched road in a direction approaching the other road based on the acquired lane information, An electronic device for map matching using the corrected link as a candidate link.

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