JP2014052341A - Map creation server, map creation method and map creation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To estimate a new road on the basis of location information on a plurality of vehicles.SOLUTION: A map creation server is configured to: hold map data including information indicating locations of a plurality of roads and shapes thereof; hold vehicle location data acquired from a plurality of terminal devices mounted onto a plurality of vehicles and including a coordinate value at each time of each of the vehicles; specify the coordinate value outside a range of a road included in the map data of the coordinate values included in the vehicle location data; calculate a center of a distribution of the specified coordinate value in each of a plurality of ranges within coordinate space; estimate a line connecting a plurality of centers of the distribution as a new road; exclude a line connecting of the plurality of centers of the distribution having one end of the line connected to the road included in the map data and the other end thereof not connected to the road included in the map data from the new road; and transmit map update data including information on a location of the new road and a shape thereof to the plurality of terminal devices.

Description

  The present invention relates to a technique for generating map data.

  As a background art of this technical field, there is JP 2009-150796 A (Patent Document 1). In this publication, “in the navigation device 1, storage means (7, 8) capable of storing map information and updating new map information, and detecting the current position of the navigation device 1 as a detection position 2. A road data presence / absence determining means 6 for determining whether or not the detected position exists on the road of the map, and a plurality of positions detecting means (2, 3) when it is determined that the detected position is not on the road. The new detection route is divided into one or more new detection sections based on the new detection route detection means 6 for detecting a trajectory connecting the detected positions as a new detection route and whether the vehicle has traveled over a predetermined distance at a predetermined traveling speed or higher. A newly detected route discriminating means 6 for discriminating and a road data updating means 6 for updating the new road data to the storage means (7, 8).

JP 2009-150796 A

  Based on position information acquired by an in-vehicle terminal such as a navigation device, for example, if a movement locus of an in-vehicle terminal (that is, a vehicle equipped with the in-vehicle terminal) is simply recognized as a road, a place that is not actually a road is a road May be recognized as This is because the vehicle may travel on a place other than the road (for example, a parking lot).

  The present invention has been made in view of the above problems, and an object of the present invention is to create highly accurate map data by excluding a portion other than a road from position information of an in-vehicle terminal.

  In order to solve the above problems, the present invention includes an interface connected to a network, a processor connected to the interface, and a storage device connected to the processor, and a plurality of road positions and shapes. Map data including information indicating the vehicle position data acquired from a plurality of terminal devices mounted on a plurality of vehicles, including vehicle position data including coordinate values at each time of each vehicle, and included in the vehicle position data A coordinate value outside the range of the road included in the map data is specified, and a center of the distribution of the specified coordinate value in each of the plurality of ranges in the coordinate space is calculated, A line connecting the distribution centers is estimated as a new road, one end is connected to the road included in the map data, and the other end is not connected to the road included in the map data The line connecting the serial centers of distribution, excluded from the new road, and transmits the map update data including information indicating the position and shape of the new road to the plurality of terminal devices.

  According to one embodiment of the present invention, highly accurate map data can be created based on position information acquired by an in-vehicle terminal.

  Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

It is a block diagram which shows the structure of the map generation system of embodiment of this invention. It is explanatory drawing of the vehicle position data stored in the vehicle position data storage part of embodiment of this invention. It is explanatory drawing of the 1st example of the vehicle position data of embodiment of this invention. It is explanatory drawing of the 2nd example of the vehicle position data of embodiment of this invention. It is explanatory drawing of the 3rd example of the vehicle position data of embodiment of this invention. It is explanatory drawing of the 4th example of the vehicle position data of embodiment of this invention. It is a flowchart which shows the new road data estimation process which the map server of embodiment of this invention performs. It is a flowchart which shows the process which estimates the road shape contained in the new road data estimation process which the map server of embodiment of this invention performs. It is explanatory drawing of the 1st example of the process which specifies the center of distribution of a coordinate value which the map server of embodiment of this invention performs. It is explanatory drawing of the 2nd example of the process which specifies the center of distribution of coordinate value which the map server of embodiment of this invention performs.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a map generation system according to an embodiment of the present invention.

  The map generation system of this embodiment includes a map server 10 connected to a network 40 and a plurality of navigation terminals 20 that communicate with the map server 10 via the network 40.

  The map server 10 is a computer that includes a processor 17, a memory 18, a network interface (I / F) 15, a vehicle position data storage unit 11, an update data storage unit 12, and a map data storage unit 16 that are connected to one another.

  The processor 17 executes a program stored in the memory 18.

  The memory 18 is a semiconductor memory, for example, and stores a program executed by the processor 17, data referred to by the processor 17, data output from the processor 17, and the like. The memory 18 of this embodiment stores at least a new road data extraction unit 13 and an update data management unit 14 that are programs executed by the processor 17. Processing realized by the processor 17 executing the program will be described later. In the following description, the processing executed by the new road data extraction unit 13 and the like is actually executed by the processor 17 according to the program of the new road data extraction unit 13 and the like.

  The network I / F 15 is connected to the network 40 and communicates with the navigation terminal 20 and the like.

  Each of the vehicle position data storage unit 11, the update data storage unit 12, and the map data storage unit 16 may be a storage device such as a hard disk drive (HDD) or a flash memory, or a storage area in one storage device. It may be.

  The map data storage unit 16 stores map data. The map data includes coordinate values indicating the position and shape of map components (features) such as roads and buildings. The map data storage unit 16 of the present embodiment stores at least road data indicating the position, shape, connection relationship, and the like of roads as map data.

  The update data storage unit 12 stores map update data. For example, when the navigation terminal 20 holds a certain version of map data, the map update data is data that is created and transmitted in order to update the map data to a newer version of map data. At least these versions of difference data are included. As described later, when new road data is created by the new road data extraction unit 13, the difference data includes the new road data.

  The vehicle position data storage unit 11 stores vehicle position data acquired from each navigation terminal 20. Details of the vehicle position data will be described later (see FIG. 2).

  Each navigation terminal 20 is a mobile terminal mounted on a vehicle, and performs route search, output of search results, and the like in order to guide a user on the vehicle to a destination. Hereinafter, one typical configuration of the plurality of navigation terminals 20 will be described. Since the configuration of the other navigation terminals 20 may be the same as that shown in FIG. 1, illustration and description thereof are omitted.

  The navigation terminal 20 includes a processor 28, a memory 29, a network I / F 21, a position information acquisition unit 24, a screen input / output I / F 25, a management data storage unit 26, and a map data storage unit 27 that are connected to one another.

  The processor 28 executes a program stored in the memory 29.

  The memory 29 is a semiconductor memory, for example, and stores a program executed by the processor 28, data referred to by the processor 28, and the like. The memory 29 of the present embodiment stores a vehicle position transmission unit 61, a map distribution request unit 62, a map update unit 63, and a navigation processing unit 64, which are programs executed by the processor 28. In the following description, the processing executed by the vehicle position transmission unit 61, the map distribution request unit 62, the map update unit 63, and the navigation processing unit 64 is actually executed by the processor 28 according to each program.

  The vehicle position transmission unit 61 transmits the vehicle position information acquired by the position information acquisition unit 24 to the map server 10 at a predetermined timing (for example, periodically). The transmitted data is stored in the vehicle position data storage unit 11 of the map server 10 (see FIG. 2).

  The map distribution request unit 62 transmits a map update data distribution request to the map server 10. The map update unit 63 updates the map data stored in the map data storage unit 27 using the distributed map update data. The navigation processing unit 64 searches for a route to the destination based on the map data stored in the map data storage unit 27 and guides the user along the route. Since the processing of the map distribution request unit 62, the map update unit 63, and the navigation processing unit 64 can be executed by a known method in the same manner as a conventional vehicle-mounted navigation terminal, detailed description thereof will be omitted.

  The screen input / output I / F 25 includes a screen that displays map information and the like for the user, and an input device that receives input from the user. For example, the screen input / output I / F 25 may be a liquid crystal display device, a keyboard, or the like, or a liquid crystal display device with a touch pad.

  The network I / F 21 is connected to the wireless communication device 30. The wireless communication device 30 performs wireless communication with a wireless base station 31 connected to the network 40. The network I / F 21 performs communication with the map server 10 via the wireless communication device 30, the wireless base station 31, and the network 40. Transmission of vehicle position information (51) and reception of map update data (52) are realized by such communication.

  Note that the wireless communication device 30 may be built in the navigation terminal 20.

  Each of the management data storage unit 26 and the map data storage unit 27 may be a storage device such as a hard disk drive (HDD) or a flash memory, or may be a storage area in one storage device.

  The map data storage unit 27 stores map data referred to by the navigation processing unit 64. This map data is updated based on the map update data transmitted from the map server 10.

  Information for managing map data is stored in the management data storage unit 26. For example, the management data storage unit 26 stores identification information of map update data applied to the map.

  The position information acquisition unit 24 acquires position information of the navigation terminal 20 (that is, a vehicle on which the navigation terminal 20 is mounted). The acquired position information includes at least two-dimensional coordinate values such as latitude and longitude. The position information acquisition unit 24 is, for example, a GPS device that acquires position information based on a signal received from a satellite. The position information acquisition unit 24 may further include an acceleration sensor, a gyro sensor, and the like, and may use the movement amount of the vehicle calculated based on the acceleration and the angular velocity acquired by the sensor for acquiring the position information. Alternatively, when the navigation terminal 20 can acquire vehicle control information, such as travel speed, travel distance, and steering amount, from a vehicle control device (not shown), the position information acquisition unit 24 is calculated based on the information. The amount of movement of the vehicle may be used to acquire position information.

  The network 40 is connected to the Internet 41. The map server 10 may acquire a new version of map data via the Internet 41.

  The navigation terminal 20 shown in FIG. 1 is an example of a terminal device mounted on a vehicle, and some or all of the plurality of navigation terminals 20 are navigated based on other types of terminal devices, for example, map data. It may be replaced by a terminal device that provides other services.

  A vehicle equipped with a terminal device that acquires position information and transmits data including the position information, such as the navigation terminal 20, may be called a probe car, and data transmitted from the probe car is also called probe data.

  FIG. 2 is an explanatory diagram of the vehicle position data 200 stored in the vehicle position data storage unit 11 according to the embodiment of this invention.

  One record of the vehicle position data 200 includes the position information of the vehicle acquired by the position information acquisition unit 24 of the navigation terminal 20 of one vehicle at a certain time. Specifically, each record includes a device ID 201, a time stamp 202, a latitude 203, a longitude 204, and a speed 205.

  The device ID 201 is information for uniquely identifying each navigation terminal 20. The time stamp 202 is the time when the position information acquisition unit 24 of each navigation terminal 20 acquires the position information. Latitude 203 and longitude 204 are vehicle position information (that is, coordinate values) acquired by each navigation terminal 20 at each time. A speed 205 is a traveling speed of each vehicle at each time.

  For example, in the record 211, the latitude and longitude acquired by the position information acquisition unit 24 of the navigation terminal 20 identified by the identification information “001” at 12:34:00 on May 1, 2012 are 139.7337639 degrees and It is 35.66939167 degrees, indicating that the traveling speed of the vehicle equipped with the navigation terminal 20 at that time was 23 km / h.

  In addition, the navigation terminal 20 may include the acquired traveling speed in the vehicle position information and transmit it to the map server 10 when the information on the traveling speed of the vehicle can be acquired from the control device of the vehicle. On the other hand, when the information on the traveling speed of the vehicle cannot be acquired from the vehicle control device, the navigation terminal 20 determines the traveling speed based on the coordinate values acquired by the position information acquisition unit 24 and the time at which those coordinate values are acquired. The travel speed may be included in the vehicle position information and transmitted to the map server 10, or the vehicle position information not including the travel speed may be transmitted to the map server 10.

  The map server 10 stores the vehicle position information received from each navigation terminal 20 in the vehicle position data storage unit 11 so that one record includes information related to one time from one navigation terminal 20. When the received vehicle position information does not include the speed, the map server 10 calculates the speed of each vehicle at each time based on the time stamp 202, the latitude 203 and the longitude 204 acquired from each navigation terminal 20, and calculates the result. The speed 205 may be stored. For example, since the records 211, 214, and 217 include the latitude and longitude 204 of each time acquired from one navigation terminal 20, the speed of each vehicle of the vehicle on which the navigation terminal 20 is mounted is calculated based on them. be able to. Similarly, the speed of another vehicle can be calculated based on records 212, 215 and 218, and the speed of another vehicle can be calculated based on records 213, 216 and 219.

  Alternatively, the vehicle position data 200 may not include the speed 205, but in that case, the map server 10 determines that each vehicle at each time is based on the time stamp 202, the latitude 203, and the longitude 204 as necessary. Calculate speed.

  Each navigation terminal 20 may transmit the vehicle position information including the position information at that time to the map server 10 every time the position information acquisition unit 24 acquires the position information at each time. Vehicle position information including all coordinate values acquired (for example, one day) may be collectively transmitted to the map server 10 (transmission step 51 in FIG. 1). In the present embodiment, since map information including new road data is created based on position information collected from a plurality of vehicles over a certain period of time, immediacy is not required for transmission of vehicle position information.

  Hereinafter, an example of the vehicle position data 200 will be described with reference to FIGS. 3A to 3D. In these examples, “existing roads” are roads in which the map data storage units 16 and 27 hold information indicating their positions, shapes, connection relationships with other roads, and the like. The navigation processing unit 64 can perform a route search for roads held in the map data storage unit 27. On the other hand, the “new road” is a road for which information indicating the position, shape, connection relationship with other roads, etc. is not yet held in any of the map data storage units 16 and 27.

  In addition, since the coordinate value acquired by the position information acquisition unit 24 includes an error, in actuality, the coordinate value of a point off the road may be acquired as the position information of the vehicle traveling on the road. . Therefore, in general, the navigation terminal 20 collates the coordinate value acquired by the position information acquisition unit 24 with the position and shape of the road stored in the map data storage unit 27 to determine which road the vehicle has. It has a so-called map matching function that estimates whether the vehicle is running. Even when a coordinate value deviating from the road is acquired by map matching, the coordinate value may be corrected to a coordinate value on the road. In the present embodiment, an example is shown in which each navigation terminal 20 transmits vehicle position information including coordinate values before being corrected by map matching (transmission step 51 in FIG. 1). However, as will be described later, the present invention can also be applied when vehicle position information including coordinate values corrected by map matching is transmitted.

  FIG. 3A is an explanatory diagram of a first example of the vehicle position data 200 according to the embodiment of this invention.

  In FIG. 3A, as an example, when there are existing roads 301A and 301B and new roads 302A connecting them, coordinate values acquired from a plurality of navigation terminals 20 of a plurality of vehicles traveling on the respective roads (that is, The position specified by the latitude 203 and the longitude 204) is displayed by an X-type symbol. Since map matching is not performed as described above, coordinate values vary within the road range, and some coordinate values are out of the road range. The existence of such variations is the same in FIGS. 3B to 3D described later.

  FIG. 3B is an explanatory diagram of a second example of the vehicle position data 200 according to the embodiment of this invention.

  In FIG. 3B, as an example, when there is an existing road 301C and a parking lot 303A connected thereto, coordinate values acquired from a plurality of navigation terminals 20 of a plurality of vehicles that have traveled there are displayed.

  A typical example of a place other than a road on which vehicles pass is a parking lot. One of the typical shapes of the parking lot is that only one end thereof is connected to the existing road and the other end is not connected to the existing road. FIG. 3B shows an example of such a parking lot. One end of the parking lot 303A is connected to the existing road 301C, but the other end is not connected to any road. The new road data extraction unit 13 of the present embodiment excludes a group of coordinate values distributed in a shape in which only one end is connected to a road as described above from the estimation of a new road. This can prevent the parking lot from being erroneously estimated as a new road, improving the accuracy of map data creation.

  A method for estimating a new road or the like based on the distribution of coordinate values and a method for determining whether or not the estimated new road or the like is connected to an existing road will be described later (FIGS. 5A, 5B and FIG. See 3D etc.).

  On the other hand, the above method has several problems. One of the problems is that when a new road with a dead end actually exists, the new road is erroneously determined to be a parking lot, so that it is not estimated as a new road. However, even if a dead-end road is registered in the map data, it will not be selected as a route unless a facility or residence facing the road is designated as a departure place or destination. That is, since a person who uses a dead-end road is limited to a resident of a residence facing the road or a user of a facility facing the road, such road data is distributed to many navigation terminals 20. The profit to do is considered to be small.

  Another problem is that a parking lot having a shape in which one end is connected to an existing road and the other end is also connected to the existing road is erroneously estimated as a new road. A method for dealing with this problem will be described later with reference to FIG. 3C.

  Yet another problem is that, depending on the relationship between the speed of the vehicle and the timing at which the position information acquisition unit 24 acquires position information, it is determined that a new road that is actually connected to an existing road is not connected. It is possible that A method for dealing with this problem will be described later with reference to FIG. 3D.

  FIG. 3C is an explanatory diagram of a third example of the vehicle position data 200 according to the embodiment of this invention.

  In FIG. 3C, as an example, coordinate values acquired from a plurality of navigation terminals 20 of a plurality of vehicles that have traveled on the existing roads 301D and 301E and a parking lot 303B attached to the facility 304 facing them are displayed. Yes.

  In this example, the parking lot 303B is connected to both the existing roads 301D and 301E. Therefore, there is a possibility that the parking lot 303B is erroneously estimated as a new road based on the coordinate value of the vehicle that has traveled in the parking lot 303B, and this error cannot be prevented by the method described with reference to FIG. 3B.

  Therefore, the new road data extraction unit 13 of the present embodiment determines whether or not the coordinate value is that of a vehicle that has traveled on the new road, based on the variation in the distribution of coordinate values. Specifically, the coordinate values acquired from the navigation terminals 20 of a plurality of vehicles that have traveled in the parking lot generally vary over a wide range as shown in FIG. 3C. For this reason, the new road data extraction unit 13 calculates a variation (for example, a variance value) of the distribution of coordinate values, and when the variance value exceeds a predetermined value, the new road data extraction unit 13 does not use the distribution for estimating a new road. This can prevent the parking lot 303B from being erroneously estimated as a new road.

  A specific method for calculating the distribution of coordinate values will be described later (see FIGS. 5A and 5B).

  FIG. 3D is an explanatory diagram of a fourth example of the vehicle position data 200 according to the embodiment of this invention.

  In FIG. 3D, as an example, coordinate values acquired from a plurality of navigation terminals 20 of a plurality of vehicles traveling on existing roads 301F, 301G, and 301H and a new road 302B are displayed. Similar to FIGS. 3A to 3C, the acquired coordinate values are displayed by X-type symbols. On the other hand, coordinate values 305A to 305J displayed by triangular symbols are coordinate values at each time acquired from the navigation terminal 20 of one vehicle (hereinafter referred to as the vehicle in the description of FIG. 3D). As described with reference to FIG. 2, since the vehicle position data 200 includes the device ID 201, a plurality of coordinate values acquired from one vehicle can be specified based on the device ID 201.

  The example of FIG. 3D shows an example in which the vehicle travels on the existing road 301G, then enters the new road 302B, and further enters the existing road 301F from the new road 302B. For example, when the position information acquisition unit 24 of the navigation terminal 20 of the vehicle acquires coordinate values at intervals of T seconds, the coordinate value 305A is a coordinate value acquired at a certain time (T0), and the coordinate value 305B is the T The coordinate value is acquired after 2 seconds (T0 + T), and the coordinate value 305C is the coordinate value acquired 30 seconds later (T0 + 2T). Similarly, coordinate values 305D to 305J indicate coordinate values obtained sequentially every T seconds.

  As will be described later, the new road data extraction unit 13 of the present embodiment estimates a new road based on the distribution of coordinate values acquired from the plurality of navigation terminals 20, but here, in order to simplify the description, The description will be made assuming that the new road 302B is estimated based on the values 305A to 305J.

  First, a first method for determining a connection between an existing road and a new road will be described. For example, the new road data extraction unit 13 estimates a line connecting the coordinate values 305D to 305F as the new road 302B. Whether or not the new road 302B is connected to the existing road 301G is determined based on, for example, the distance between the existing road 301G and the coordinate value 305D closest to the existing road 301G among the coordinate values 305D to 305F. For example, when the distance between the coordinate value 305D and the existing road 301G is smaller than a predetermined value, the new road data extraction unit 13 determines that the new road 302B is connected to the existing road 301G.

  However, when the first method is adopted, it is determined that a new road that should be actually connected to an existing road is not connected depending on the relationship between the traveling speed of the vehicle and the coordinate value acquisition interval. There is. In FIG. 3D, since the traveling speed after the vehicle has passed the point of the coordinate value 305F is sufficiently large, the distance between the coordinate value 305F closest to the existing road 301F and the existing road 301F is larger than the predetermined value. Here is an example. Even in such a case, it may be determined that the new road 302B is connected to the existing road 301F by the following second method or third method.

  For example, when the speed 205 of the vehicle in the coordinate value 305F and the distance between the coordinate value 305F and the existing road 301F satisfy the predetermined conditions, the new road data extraction unit 13 specifically includes, for example, the coordinate value 305F. Even if it is determined that the new road 302B is connected to the existing road 301F when the speed 205 of the vehicle in the road is greater than the predetermined value and the distance between the coordinate value 305F and the existing road 301F is smaller than the predetermined value. Good. This is the second method.

  The reason why the connection of the new road can be determined by the second method is as follows. If the new road 302B is a dead end road that is not actually connected to the existing road 301F, the vehicle should stop at or near the coordinate value 305F corresponding to that end. If the speed 205 at the coordinate value 305F is larger than the predetermined value, it is estimated that the vehicle is not stopped at or near the coordinate value 305F. If the distance between the coordinate value 305F and the existing road 301F is smaller than the predetermined value, It is estimated that the vehicle has traveled from the coordinate value 305F to the existing road 301F, that is, there is a new road connecting the coordinate value 305F and the existing road 301F.

  Next, the third method will be described. It is determined that one end (for example, the end on the coordinate value 305D side) of the new road 302B is connected to the existing road 301G, but the other end (for example, the end on the coordinate value 305F side) is connected to the existing road 301F. When it is unknown, the new road data extraction unit 13 determines whether the relationship between the coordinate value 305F and the coordinate value of the vehicle on the existing road 301F (for example, the coordinate value 305G) satisfies a predetermined condition. However, when the condition is satisfied, it may be determined that the new road 302B is connected to the existing road 301F.

  Specifically, the new road data extraction unit 13 first assumes that the end on the coordinate value 305F side of the new road 302B to be determined for connection is not connected to the existing road 301F, The shortest route from the coordinate value 305F to the coordinate value 305G via the road is searched. In the example of FIG. 3D, a new road 302B whose end on the coordinate value 305D side is connected to the existing road 301G, and a route 306A through the existing roads 301G, 301H, and 301F are searched.

  Then, the new road data extraction unit 13 calculates the traveling speed of the vehicle necessary to pass through the route between the time when the coordinate value 305F is acquired and the time when the coordinate value 305G is acquired. When the traveling speed is larger than the predetermined value, the new road data extraction unit 13 determines that the end of the new road 302B on the coordinate value 305F side is connected to the existing road 301F.

  For example, if the calculated traveling speed greatly exceeds the speed limit set for the searched route, it is unlikely that the vehicle actually traveled the route. The end on the 305F side is connected to the existing road 301F, and it is estimated that a route 306B passing through the connection point exists.

  As described above, FIG. 3D is simplified, but in reality, a new road is estimated based on the distribution of coordinate values of a plurality of vehicles, as will be described later. That is, vehicles other than the vehicle also travel on the new road 302B, the coordinate values of these vehicles are also acquired, and the new road 302B is estimated based on the line connecting the centers of the distribution of these coordinate values. In such a case, the first to third methods described above are realized as follows. Here, one end of a line connecting the centers of the distribution of coordinate values is the center of the distribution of a plurality of coordinate values including the coordinate value 305D, and the other end of the line is a plurality of lines including the coordinate value 305F. A case where it is the center of the distribution of coordinate values will be described.

  In this case, when the first method is adopted, actually, one end of a line connecting the centers of the distribution (for example, the center of the distribution of a plurality of coordinate values including the coordinate value 305D) and the existing road (for example, the existing road 301G). ) Is compared with a predetermined value. When the second method is adopted, the speed of any vehicle corresponding to one end of a line connecting the centers of the distribution (for example, the speed 205 of the vehicle at the coordinate value 305F) is compared with a predetermined value, and the center of the distribution The distance between one end of the line connecting the two (for example, the center of the distribution of a plurality of coordinate values including the coordinate value 305F) and the existing road (for example, the existing road 301F) is compared with a predetermined value. When the third method is adopted, the coordinate value of any vehicle corresponding to one end of the line connecting the distribution centers (for example, the coordinate value 305F of the vehicle) and the coordinate value on the existing road of the vehicle (for example, It is determined whether or not the relationship with the coordinate value 305G) on the existing road 301F satisfies a predetermined condition.

  For example, when the new road data extraction unit 13 determines that the new road 302B is connected to the existing road 301F, the new road data extraction unit 13 extends the line connecting the centers of the already calculated distributions to the existing road 301F, and extends it to the new road 301F. It may be estimated as a part of 302B.

  By the above first to third methods, the connection between the existing road and the new road can be determined with higher accuracy, and as a result, the accuracy of the created map data is improved.

  FIG. 4A is a flowchart illustrating new road data estimation processing executed by the map server 10 according to the embodiment of this invention.

  First, the new road data extraction unit 13 of the map server 10 refers to the vehicle position data 200 stored in the vehicle position data storage unit 11 and the map data (not shown) stored in the map data storage unit 16. Among the records included in the vehicle position data 200, a record having a coordinate value outside the range of the existing road is specified (step 401).

  Here, when the map data storage unit 16 stores information for identifying the center line of the road as data indicating the position and shape of the road, the range of the existing road is a predetermined center around the center line. It may be a range of widths. Or when the information which specifies the outline of a road is stored as data which shows the position and shape of a road, the range of the existing road may be the range inside the outline, and the inside of the outline It may be a range obtained by expanding the range by a predetermined amount. Such expansion takes into account that the coordinate value of the vehicle traveling on the road may deviate from the road due to the error of the coordinate value acquired by the position information acquisition unit 24.

  Next, the new road data extracting unit 13 excludes the data specified in step 401 (in other words, the records stored in the vehicle position data 200 from which records having coordinate values within the range of the existing road are excluded. A new road is estimated based on the data of the record (step 402). Details of this estimation process will be described later with reference to FIG. 4B.

  Next, the new road data extraction unit 13 excludes those that are not connected to the existing road from the new road estimated in Step 402, and includes a new road that includes information for identifying at least the position and shape of the remaining new road. Data is stored in the map data storage unit 16 (step 403). Specifically, out of the estimated new roads, roads whose both ends are not connected to the existing road are excluded. Further, as described with reference to FIG. 3B, a new road whose one end is connected to the existing road and whose other end is not connected to the existing road is also excluded.

  Thus, new road data including at least information specifying the position and shape of the new road is generated. The update data management unit 14 updates the map data stored in the map data storage unit 16 based on the generated new road data.

  Further, the map server 10 transmits map update data including such new road data to each navigation terminal 20 at an appropriate timing (transmission step 52 in FIG. 1). The navigation terminal 20 may update the map data stored in the map data storage unit 27 based on the received map update data including the new road data, and execute an application such as a route search based on the updated map data. it can.

  FIG. 4B is a flowchart showing a process for estimating the road shape included in the new road data estimation process executed by the map server 10 according to the embodiment of the present invention.

  The process shown in FIG. 4B is executed in step 402 in FIG. 4A.

  First, the new road data extraction unit 13 specifies the distribution of coordinate values in each of a plurality of ranges in the coordinate space for the coordinate values included in the record specified in step 401 (step 411). A line connecting the specified centers of the range is estimated as a road shape (for example, a center line of a road) (step 412).

  A typical example of the processing executed in step 411 will be described in detail with reference to FIGS. 5A and 5B.

  FIG. 5A is an explanatory diagram of a first example of processing for specifying the center of the distribution of coordinate values, which is executed by the map server 10 according to the embodiment of this invention.

  3A to 3D, the X-type symbol shown in FIG. 5A indicates coordinate values acquired from the navigation terminals 20 of a plurality of vehicles.

  Ranges 501A and 501B shown in FIG. 5A are ranges separated by two straight lines that are parallel to the coordinate space in an arbitrary direction (the x-axis direction in the example of FIG. 5A) and have a predetermined interval. . Similarly, each of the ranges 501C and 501D includes two straight lines that are parallel to the coordinate space in one direction different from the above (in the example of FIG. 5A, the y-axis direction orthogonal to the x-axis) and have a predetermined interval. Is a range delimited by. For example, the x-axis direction may be a latitude direction and the y-axis direction may be a meridian direction.

  In step 411, the new road data extraction unit 13 calculates frequency distributions 502A to 502D of coordinate values in the ranges 501A to 501D, respectively. Then, the new road data extraction unit 13 calculates the center of the calculated frequency distribution whose variation (for example, variance value) is equal to or less than a predetermined value. In the example of FIG. 5A, since the variance value of the frequency distribution 502B exceeds a predetermined value, the frequency distribution 502B is excluded from the estimation of the new road, and the new road data extraction unit 13 determines the center of each of the frequency distributions 502A, 502C, and 502D. 503A, 503C and 503D are calculated. This calculation may be performed by any method. In the present embodiment, calculation is performed by the least square method for the Gaussian distribution, and the median values of the respective Gaussian distributions are the centers 503A, 503C, and 503D.

  Next, in step 412, the new road data extraction unit 13 estimates a line 504A connecting the calculated distribution centers 503A, 503C, and 503D as the shape of the new road (for example, the center line of the new road). Although only four ranges 501A to 501D are shown in FIG. 5A for the sake of simplicity of explanation, the shape of a new road can be improved to a higher resolution by actually setting more ranges and performing estimation based on them. Can be expected.

  The reason for excluding the center of the distribution whose variance value exceeds a predetermined value from the estimation of the new road is as described with reference to FIG. 3C. In the example of FIG. 5A, since the range for calculating the distribution is set regardless of the shape of the new road, for example, in the range 501B in which the direction of the new road is substantially parallel to the x-axis direction, the variance value increases. The center is excluded from new road estimation. However, in such a case, the frequency distribution 502D variance value in the range 501D in the y-axis direction orthogonal to the x-axis direction becomes small, so that the center can be used for estimation of a new road. On the other hand, in the case of a parking lot, as shown in FIG. 3C, since the variance value of the distribution of the range in any direction becomes large, the entire parking lot is removed from the new road by excluding those distributions from the estimation of the new road. Can be excluded.

  FIG. 5B is an explanatory diagram of a second example of the process of specifying the center of the distribution of coordinate values executed by the map server 10 according to the embodiment of this invention.

  3A to 3D, the X-type symbol shown in FIG. 5B indicates coordinate values acquired from the navigation terminals 20 of a plurality of vehicles. Further, as in FIG. 3D, the triangular symbol indicates a coordinate value acquired from the navigation terminal 20 of one vehicle. By connecting the coordinate values of the vehicle in the order of the acquired times, the travel locus 505 of the vehicle is acquired. Each of the ranges 501E and 501F shown in FIG. 5B is a range having a predetermined width centered on a straight line orthogonal to the travel locus 505.

  In step 411, the new road data extraction unit 13 calculates the frequency distributions 502E and 502F of the coordinate values in the ranges 501E and 501F, and calculates the center of those having a variance value equal to or less than a predetermined value. This calculation method may be the same as in FIG. 5A. In the example of FIG. 5B, since the variance values of the frequency distributions 502E and 502F are not more than a predetermined value, the respective centers 503E and 503F are calculated.

  Next, in step 412, the new road data extraction unit 13 estimates a line 504B connecting the calculated distribution centers 503E and 503F as the shape of the new road (for example, the center line of the new road). Also in the example of FIG. 5B, it can be expected that the shape of the new road is estimated with high resolution by performing estimation based on a larger range.

  Methods other than those described above are also known as methods for estimating the center line of a new road based on the distribution of coordinate values (for example, JP 2008-267875 A). Any method can be applied to this embodiment.

  When the number of coordinate values included in the range set in step 411 is small, it is considered that these coordinate values do not have enough reliability to be used for estimating a new road. For example, such coordinate values may have been obtained from a vehicle that accidentally traveled in a place other than a road, such as a vacant lot. Moreover, even if those coordinate values were obtained from a vehicle that actually traveled on a new road, a small number of those coordinate values means that the number of times that the new road was used was small. However, the usefulness of the new road is considered to be low. For this reason, when the number of coordinate values included in the set range is smaller than a predetermined value, the new road data extraction unit 13 may exclude those coordinate values from the estimation of the new road.

  On the other hand, when the number of coordinate values included in the set range is sufficiently large, it is expected that a new road with a certain degree of reliability can be estimated based on them. However, when those coordinate values are obtained from the navigation terminal 20 of one or a small number of vehicles, it is considered that the usefulness of the estimated new road is low. For example, such coordinate values may have been obtained from a specific small number of vehicles that have repeatedly traveled on roads and the like in private land, and such roads cannot be used for route searching for general vehicles. Therefore, the new road data extraction unit 13 determines that the number of device IDs 201 corresponding to the coordinate values included in the set range (in other words, the number of vehicles that have passed through the range) is less than a predetermined value. May be excluded from the estimation of a new road. For example, when the device IDs 201 corresponding to all coordinate values included in the range are the same, the number of device IDs 201 corresponding to the coordinate values included in the range is “1” (that is, the range is a single unit). Only the vehicle has passed).

  By excluding the coordinate values satisfying the predetermined condition from the estimation of the new road as described above, it is possible to exclude the position information with low reliability and the new road with low usefulness.

  The above description relates to an example in which the coordinate values stored in the vehicle position data storage unit 11 are not corrected by the map matching function of the navigation terminal 20, but the new road data extraction unit 13 is controlled by the map matching function. A new road can also be estimated based on the corrected coordinate values. When map matching is performed, even if a coordinate value deviates from an existing road, it may be corrected as a coordinate value on the existing road if it is close to the existing road. The new road data extracting unit 13 also excludes the coordinate values corrected in this way in step 401 in FIG. 4 and could not correct the remaining coordinate values (that is, the coordinate values on the existing road by map matching). A new road can be estimated by executing step 402 and the subsequent steps on the coordinate value.

  According to the above embodiment of the present invention, a highly useful new road can be estimated with high accuracy based on position information acquired from a plurality of navigation terminals 20 mounted on a plurality of vehicles.

  In addition, this invention is not limited to above-described embodiment, Various modifications are included. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to the one having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. In addition, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. Further, each of the above-described configurations, functions, and the like may be realized by software by interpreting and executing a program that realizes each function by the processor. Information such as programs, tables, and files for realizing each function is stored in a non-volatile semiconductor memory, a hard disk drive, a storage device such as an SSD (Solid State Drive), or a computer-readable non-readable information such as an IC card, an SD card, or a DVD. It can be stored on a temporary data storage medium.

  Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

DESCRIPTION OF SYMBOLS 10 Map server 11 Vehicle position data storage part 12 Update data storage part 13 New road data extraction part 14 Update data management part 15, 21 Network interface (I / F)
16, 27 Map data storage unit 17, 28 Processor 18, 29 Memory 20 Navigation terminal 24 Position information acquisition unit 25 Screen input / output I / F
26 Management data storage unit 30 Wireless communication device 31 Wireless base station 40 Network 41 Internet 61 Vehicle position transmission unit 62 Map distribution request unit 63 Map update unit 64 Navigation processing unit

Claims (15)

An interface connected to a network, a processor connected to the interface, and a storage device connected to the processor,
Holds map data containing information indicating the location and shape of multiple roads,
Obtained from a plurality of terminal devices mounted on a plurality of vehicles, holding vehicle position data including coordinate values at each time of each vehicle,
Among the coordinate values included in the vehicle position data, specify a coordinate value outside the range of the road included in the map data,
Calculating the center of the distribution of the identified coordinate values in each of a plurality of ranges in the coordinate space;
Estimating a line connecting the centers of the plurality of distributions as a new road,
A line connecting the centers of the plurality of distributions, one end of which is connected to the road included in the map data and the other end is not connected to the road included in the map data, is excluded from the new road,
A map generation server, wherein map update data including information indicating the position and shape of the new road is transmitted to the plurality of terminal devices. The map generation server according to claim 1,
Calculating a variation in the distribution of the identified coordinate values in each of the plurality of ranges;
A map generation server, wherein a line connecting the centers of distributions in which the calculated variation is smaller than a predetermined value among the plurality of distributions is estimated as the new road. The map generation server according to claim 1,
When the distance between the center of the distribution corresponding to one end of the line connecting the centers of the plurality of distributions and the road included in the map data is smaller than a predetermined value, one end of the line connecting the centers of the plurality of distributions is the A map generation server, characterized in that it is determined to be connected to a road included in map data. The map generation server according to claim 1,
The vehicle position data further includes information indicating a traveling speed of each vehicle at each time,
The distance between the center of the distribution corresponding to one end of the line connecting the centers of the plurality of distributions and the road included in the map data, and the traveling of the vehicle at one end of the line connecting the centers of the plurality of distributions When the speed satisfies a predetermined condition, the map generation server determines that one end of a line connecting the centers of the plurality of distributions is connected to a road included in the map data. The map generation server according to claim 1,
The vehicle position data further includes information for associating information for identifying the vehicles with coordinate values at the times of the vehicles,
The first coordinate value at the first time of the first vehicle included in the distribution corresponding to one end of a line connecting the centers of the plurality of distributions, and the first within the range of the road included in the map data. It is determined whether or not the relationship between the vehicle and the second coordinate value at the second time satisfies a predetermined condition, and one end of a line connecting the centers of the plurality of distributions when the predetermined condition is satisfied It is determined that is connected to a road included in the map data. The map generation server according to claim 5,
When it is determined that the other end of the line connecting the centers of the plurality of distributions is connected to the road included in the map data, the first vehicle is set to the first time and the second time. The point of the first coordinate value and the second coordinate via a shortest route including the other end of the line connecting the centers of the plurality of distributions and the road included in the map data. A map generation characterized in that a travel speed necessary to move between the value points is calculated, and when the calculated travel speed exceeds a predetermined value, it is determined that the predetermined condition is satisfied. server. The map generation server according to claim 1,
The vehicle position data further includes information for associating information for identifying each vehicle with coordinate values at each time of each vehicle,
Based on the vehicle position data, identify the number of vehicles that have passed each of the plurality of ranges in the coordinate space,
The map generation server, wherein the center of the distribution of the coordinate values in the range in which the number of passing vehicles is less than a predetermined value is excluded from the estimation of the new road. A map generation method executed by a map generation server comprising an interface connected to a network, a processor connected to the interface, and a storage device connected to the processor,
The storage device
Holds map data containing information indicating the location and shape of multiple roads,
Obtained from a plurality of terminal devices mounted on a plurality of vehicles, holding vehicle position data including coordinate values at each time of each vehicle,
The map generation method includes:
A first procedure in which the processor specifies a coordinate value outside the range of the road included in the map data among the coordinate values included in the vehicle position data;
A second procedure in which the processor calculates a center of the distribution of the identified coordinate values in each of a plurality of ranges in a coordinate space, and estimates a line connecting the plurality of centers of the distribution as a new road;
A third step of excluding, from the new road, a line connecting the centers of the plurality of distributions, one end of which is connected to a road included in the map data and the other end is not connected to a road included in the map data; When,
A map generation method comprising: a fourth procedure in which the processor transmits map update data including information indicating a position and a shape of the new road to the plurality of terminal devices via the interface. The map generation method according to claim 8,
In the second procedure, the processor calculates a variation in the distribution of the specified coordinate values in each of the plurality of ranges, and the distribution of the calculated variation among the plurality of distributions is smaller than a predetermined value. A map generation method comprising a step of estimating a line connecting the centers as the new road. The map generation method according to claim 8,
When the distance between the center of the distribution corresponding to one end of a line connecting the centers of the plurality of distributions and the road included in the map data is smaller than a predetermined value, the third procedure includes: A map generation method comprising a step of determining that one end of a line connecting the centers of distributions is connected to a road included in the map data. The map generation method according to claim 8,
The vehicle position data further includes information indicating a traveling speed of each vehicle at each time,
The third procedure includes any one of a distance between the center of the distribution corresponding to one end of a line connecting the centers of the plurality of distributions and a road included in the map data, and one end of a line connecting the centers of the plurality of distributions. When the traveling speed of the vehicle satisfies a predetermined condition, the processor includes a procedure for determining that one end of a line connecting the centers of the plurality of distributions is connected to a road included in the map data. A map generation method. The map generation method according to claim 8,
The vehicle position data further includes information for associating information for identifying the vehicles with coordinate values at the times of the vehicles,
In the third procedure, the processor includes a first coordinate value at a first time of a first vehicle included in the distribution corresponding to one end of a line connecting the centers of the plurality of distributions, and the map data. Determining whether the relationship between the second coordinate value at the second time of the first vehicle within the range of the included road satisfies a predetermined condition, and when the predetermined condition is satisfied, A map generation method comprising a step of determining that one end of a line connecting the centers of a plurality of distributions is connected to a road included in the map data. The map generation method according to claim 12,
In the third procedure, when it is determined that the other end of the line connecting the centers of the plurality of distributions is connected to a road included in the map data, the first vehicle is connected to the first time and the first time. The point of the first coordinate value via the shortest route including the other end of the line connecting the centers of the plurality of distributions and the road included in the map data between the second time and the second time When the processor calculates a traveling speed necessary for moving between the second coordinate value and the point of the second coordinate value, and the calculated traveling speed exceeds a predetermined value, the predetermined condition is satisfied. A map generation method comprising a determination procedure. The map generation method according to claim 8,
The vehicle position data further includes information for associating information for identifying each vehicle with coordinate values at each time of each vehicle,
In the second procedure, the processor specifies the number of vehicles that have passed through each of the plurality of ranges in the coordinate space based on the vehicle position data, and the number of vehicles that have passed is less than a predetermined value. A map generation method comprising a step of excluding the center of the distribution of the coordinate values in the range from the estimation of the new road. A map generation system having a map generation server connected to a network, and a plurality of terminal devices each mounted on a vehicle and communicating with the map generation server via the network,
Each terminal device is
A first interface that communicates with the map generation server via the network, a position information acquisition unit that acquires a coordinate value of a vehicle equipped with each terminal device, and the first interface and the position information acquisition unit. A first processor,
Via the first interface, the vehicle position data including the coordinate values at each time acquired by the position information acquisition unit is transmitted to the map generation server,
The map generation server
A second interface connected to the network, a second processor connected to the second interface, and a storage device connected to the second processor,
Holds map data containing information indicating the location and shape of multiple roads,
Holding the vehicle position data acquired from the plurality of terminal devices;
Among the coordinate values included in the vehicle position data, specify a coordinate value outside the range of the road included in the map data,
Calculating the center of the distribution of the identified coordinate values in each of a plurality of ranges in the coordinate space;
Estimating a line connecting the centers of the plurality of distributions as a new road,
A line connecting the centers of the plurality of distributions, one end of which is connected to the road included in the map data and the other end is not connected to the road included in the map data, is excluded from the new road,
A map generation system, wherein map update data including information indicating the position and shape of the new road is transmitted to the plurality of terminal devices.

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