JP2005267470A - One-way traffic determination method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To automatically determine whether or not a road to be determined is a one-way traffic road in a one-way traffic determination method suitable for determinig whether or not a road being the contents of a road map for a navigation system or the like is the one-way traffic road. <P>SOLUTION: Probe information including coordinate information corresponding to a desired road is selected, and a one-way traffic regulation of the road is determined based on the distribution of the azimuth information of the selected probe information. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a one-way determination method. More particularly, the present invention relates to a one-way determination method suitable for determining whether or not a road as a road map content for a navigation system or the like is one-way.

Conventionally, updating of road map contents (roads, intersections, traffic lights, etc.) has been performed by fieldwork. For example, a person in charge is assigned to each area, and the person in charge visits the area to confirm the content of road map content (road information: corresponding to “one-way” in the present invention). Here, the road information related to the content can include one-way restrictions, entry prohibition restrictions, intersections, and the like. These road information can be used to operate the navigation system.
In addition, although patent document 1, patent document 2, etc. can be mentioned as a technique which collects information using a probe car, neither makes the road information of the content of a road map the object of update. Reference should be made to Patent Document 3 and Patent Document 4 as techniques related to the present invention.

JP 2001-209883 A JP 2002-189792 A JP 2002-150495 A JP 2003-207342 A

As described above, it takes a great deal of money and time to manually update the content of road maps in a wide area, for example, all over Japan.
Accordingly, an object of the present invention is to make it possible to easily and quickly determine whether or not a road to be determined is one-way, by paying attention to a one-way restriction on a road among contents.

The present invention aims to solve the above problems as follows. That is,
Select probe information including coordinate information corresponding to the desired road,
A one-way determination method, comprising: determining one-way restriction on the road based on a distribution of direction information of the selected probe information.

  According to this one-way determination method, it is possible to automatically determine whether or not the desired road is one-way based on the probe information of the probe car. Therefore, the determination work can be performed more inexpensively and quickly.

  In the present invention, the probe information of the probe car includes at least coordinate information (latitude and longitude) and azimuth information when the probe car exists at the coordinates. Such information can be specified if the vehicle has a position detection function such as GPS. Also, as described in Patent Document 3, a system that performs bidirectional information transmission between a vehicle navigation system and a base station is well known. Therefore, if the information transmission system is used, a general vehicle equipped with a navigation system can be used as a probe car. Of course, this does not exclude the use of a probe car equipped with a dedicated device for collecting road information.

As the probe information, in addition to the coordinate information and the azimuth information, information related to the vehicle status of the probe car can also be used. Examples of information related to the vehicle status of the probe car include information related to probe car time information, turn signal lamps, steering wheel, brake, light, speed, and the like. More specifically, turn-on / off of the blinker lamp, brake, and light is detected, a rotation angle of the steering wheel is detected, and a speedometer value is detected for the speed.
Furthermore, information on starting and stopping of the vehicle can also be used as probe information.

Probe information corrected by map matching or the like can also be used. Thereby, the error contained in probe information can be reduced.
Here, map matching is a technique for preventing the position of the probe car from deviating from the road of the map information in the car navigation system, and as a result, the position of the probe car always exists on the road. In order to perform map matching, a travel locus is formed from the coordinate information, direction information, travel distance, etc. of the probe car in the car navigation system, and this travel locus is compared with road shape data in the map information. Since there are a plurality of road shape data, weighting is performed according to a predetermined priority, and one road is selected. Then, the coordinates of the probe car are changed to the coordinates on the road.
For details, please refer to Car Navigation System (Public Data Structure KIWI and its Usage), Chapter 4, Kyoritsu Publishing, etc.
The map matching may be performed on the base station side that has received the probe information from the probe car.

In the present invention, probe information related to a road to be determined as to whether or not the vehicle is one-way is selected based on the coordinate information.
For example, probe information including the same coordinates as the coordinates of the determination target road is selected. The probe information including the coordinates is generated by a probe car located on the determination target road. According to the study by the present inventors, since the coordinate information in the probe information includes some error, in order to eliminate the influence from other roads, a predetermined distance (first step) from both ends (intersection etc.) on the road. Those within a distance of 1 are preferably canceled. In addition, the direction of the probe car that turns right and left is not along the road in the intersection, and the direction information may become unstable. As will be described later, whether or not the road to be determined is one-way is determined based on the distribution of the direction information. Therefore, it is preferable to previously remove probe information including unstable azimuth information.
The first direction information first distance is appropriately set based on the shape of the intersection (the width of the intersecting road, the number of intersections, the angle of the intersecting road), and the like.

When the determination target road is expressed as a link, as shown in FIG. 1, a virtual region 3 having a predetermined width (first width) centered on the link 1 is set. Then, probe information including coordinate information that coincides with the coordinates in the virtual region is selected. Note that the first width can also be set as appropriate.
Even in the case where such a virtual region is set, it is preferable to cancel those within the first distance from both ends 5 and 6 thereof.

For the probe information thus selected, it is determined whether the determination target road is one-way based on the distribution of the direction information.
For example, the case where the direction of the selected probe information is deviated from the link direction of the determination target road by a predetermined intersection angle (for example, 30 degrees) or more is excluded. That is, only the probe information in the direction along the link is employed. Then, as shown in FIG. 1, the number of data is counted with the direction from the start point 5 to the end point 6 of the link as the + direction and the opposite as the-direction. In the example of FIG. 1, the number of data in the + direction is 3 and the number of data in the − direction is 2.
Based on this number of data, the one-way regulation of the determination target road is obtained. For example, when the number of data on one side of either the + direction or the − direction is extremely small, it is determined that the one-way regulation that cannot proceed in the direction is performed. If the number of data in both directions is almost balanced, it is determined that the vehicle traveling direction is not regulated on the determination target road. That is, it is determined that the determination target road is not one-way.

  More specifically, the determination process is validated when the total number of probe information in two directions along the determination target road (link) is equal to or greater than a predetermined threshold value (X). Then, when the number of data in one direction is equal to or less than a predetermined threshold (Y%) of the total number of data, it is determined that there is a one-way restriction that cannot proceed in a small direction.

  Moreover, said process can be performed for every time slot | zone. Thereby, it becomes possible to determine the one-way restriction for each desired time zone. That is, it becomes possible to determine one-way traffic on time.

Examples of the present invention will be described below.
FIG. 2 is a functional block diagram of the one-way regulation determination device of the present invention.
The computers of the probe cars P1, P2,... Pm are wirelessly connected to a network N such as the Internet. The probe car transmits probe information at predetermined intervals. The probe information includes current coordinate information (X, Y), direction information (D), and other information of the probe car. The probe information is transmitted to the central apparatus 10 via the network N and stored in the probe information memory 11.
The method of transmitting the probe information is not limited to the method via the network, but can be temporarily stored in the memory in the probe car and the probe information can be supplied from the memory directly to the probe information memory 11 via wire.

The one-way restriction determination device 12 includes a determination target road coordinate assignment device 14 for specifying a road to be determined. When the operator designates a specific road in the device 14, the link 1 of the road is read from the memory 15, and as shown in FIG. 1, the virtual region 3 having a width of 10 m centering on the link 1 is automatically designated. . In addition, in the range of nodes 5 and 6 to 5 m, it is excluded from the area designation. This is to cancel the error included in the probe information. The coordinates of the virtual area 3 are specified and sent to the coordinate comparison device 16.
The probe information stored in the probe information memory 11 is read by the probe information reading device 13, and the coordinate information in each probe information and the coordinates of the virtual region 3 designated by the determination target road coordinate applying device 14 in the coordinate comparison device 16. Information is compared.

  By specifying the acquisition time zone of the probe information read by the probe information reading device 13, the one-way regulation information in the specific time zone can be obtained. Also, probe information sent from the probe car can be directly input to the coordinate comparison device 16 to select probe information necessary for determination in real time.

  In the coordinate comparison device 16, probe information having coordinate information that matches the coordinates in the virtual region 3 is sent to the azimuth information counter 17. This azimuth information counter 17 counts the number of azimuth probe information data along the link 1 in two directions (+ direction and-direction as shown in FIG. 1). Those having an intersection angle of 30 degrees or more with respect to link 1 were excluded from the count target.

  The count result is compared by the data number comparison device 18, and the comparison result is output from the output device 19. Although the output method is not particularly limited, it is possible to display (display) the road that has been judged on the road map in a blinking manner, and display the one-way regulation information on the screen when the road is clicked. Further, the one-way regulation information related to the road whose determination has been completed in the road map can be automatically updated based on the determination result.

FIG. 3 is a block diagram showing a hardware configuration of the one-way restriction determination device 12.
The hardware configuration of the device 12 is such that various elements are coupled to the central control device 21 via the system bus 22 in the same manner as a general computer device.
The central control device 21 includes a general-purpose CPU, a memory control device, a bus control device, an interrupt control device, and a DMA (direct memory access) device. The system bus 22 also includes a data line, an address line, and a control line. A memory circuit including a RAM (Random Access Memory) 23 and a nonvolatile memory (ROM 24, CMOS-RAM 25, etc.) is connected to the system bus 22. The RAM 23 is read or rewritten by the central controller 21 or other hardware elements. The data in the non-volatile memory is read-only, and the data is not lost when the device is turned off. The system program for controlling the hardware is stored in the hard disk device 27 and is also stored in the RAM 23, and is appropriately read into the central control device 21 through the disk drive control device 26 for use. The hard disk device 27 also stores application programs for executing various data processing. Further, road information on the map is stored as a database in a predetermined area of the hard disk device 27.

  The system bus 22 is connected to a flexible drive control device 31 that reads and writes data from and to the flexible disk 32 and a CD / DVD control device 33 that reads data from the compact disk 34. In this embodiment, a printer 38 is connected to the printer interface 37.

A keyboard / mouse control device 41 is connected to the system bus 22 to enable data input from the keyboard 42 and the mouse 43. A monitor 45 is connected to the system bus 22 via a monitor control device 44. As the monitor 45, a CRT type, a liquid crystal type, a plasma display type, or the like can be used.
An empty slot 51 is prepared in order to allow the addition of various elements (such as a modem).

  The system of the embodiment is connected to the network N via the network adapter 61. A probe car is connected to the network (Internet) N.

  Programs (OS program, application program (including those of the present invention)) necessary for operating the one-way regulation determination device 12 are installed in the system via various media. For example, it is possible to install in the form of a non-write recording medium (CD-ROM, ROM card, etc.), a writable recording medium (FD, DVD, etc.), or a communication medium using the network N. Of course, these programs can be written in the nonvolatile memories 24 and 25 and the hard disk device 27 in advance.

According to such a computer system, all probe information from the probe car is taken into the system via the network adapter 61 and temporarily stored in a predetermined folder on the hard disk 27. Next, predetermined probe information is read from all probe information stored in the hard disk 27. The read probe information is temporarily stored in the RAM 23.
Next, the central control device 21 performs one-way restriction determination based on the probe information in the RAM 23 according to a predetermined program stored in the hard disk 27.

Hereinafter, the operation of the one-way determination device of the embodiment will be described (see the flowchart of FIG. 4).
In step 1, a road link to be determined for one-way traffic restriction is designated on a road map.
As illustrated in FIG. 1, the determination target road coordinate assigning device 14 designates a range (virtual region 3) having a width of 10 m around the designated link 1. In addition, the range of nodes (intersections) 5, 6 to 5m at both ends of the link is excluded. This is because the probe information on other links (roads) may be affected at both ends of the link. Moreover, since the probe car that turns right and left is not along the direction of the road in the intersection, the direction information becomes unstable. This is because the unstable data is previously removed from Step 9 (azimuth comparison processing) described later. Probe information including coordinate information that coincides with the coordinates in the virtual region 3 is extracted and used when determining one-way restriction (step 3).

Next, in step 5, the probe information reading device 13 reads probe information from the probe information memory 11.
The coordinate information of the probe information read out in this way is compared with the coordinate information in the virtual area 3 specified in step 3 by the coordinate comparison device 16. Only probe information having coordinate information equal to the coordinate information in the virtual area 3 is extracted (step 7).

In step 9, the azimuth information of the probe information extracted in step 7 is classified into those along the link 1 (intersection angle of less than 30 degrees) and those not along (intersection angle of 30 degrees or more). The latter is not counted by the azimuth information counter.
As shown in FIG. 1, the ones along the link 1 are classified into a + direction and a − direction and counted.

  In step 11, the number of data in the two directions counted in step 9 is compared. In this embodiment, (i) the total number of data along the link is 50 or more, and (ii) 10% of the total data number along the link when the number of data in one of the + direction and the − direction is along the link. Based on the following criteria, the one-way traffic restriction was determined based on the following criteria:

The result of an Example is shown to FIGS.
FIG. 5 shows a one-way restriction determined on a predetermined road extending in the north-south direction in Nagoya city. The azimuth information of the probe information in the virtual area displayed in bold lines in FIG. Extracted. The result is shown in FIG. 5B (step 13).
The number of data to be counted is 996, and 9 (0.9%) of the data is directed southward. Therefore, it was possible to determine that there was a one-way regulation facing south on this road. The road is a one-way restricted road that cannot actually travel southward.

FIG. 6 shows a one-way restriction determined on a predetermined road extending in the east-west direction in Nagoya city. The azimuth information of the probe information in the virtual area indicated by the bold line in FIG. Extracted. The result is shown in FIG.
The number of data to be counted was 106, of which 8 (7.55%) had the west direction. Therefore, it could be determined that there is a one-way restriction that cannot proceed westward on this road. The road is actually a one-way restricted road that cannot travel westward.

FIG. 7 shows a one-way restriction determined on a predetermined road extending in the north-south direction in Nagoya city. The azimuth information of the probe information in the virtual area indicated by the bold line in FIG. Extracted. The result is shown in FIG.
Since the number of data to be counted was 43, determination could not be made in this case.

  The present invention is not limited to the description of the embodiments and examples of the invention described above. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.

It is a figure explaining the basic principle of the one-way regulation determination method of this invention. It is a block diagram explaining the structure of the one-way regulation determination apparatus of the Example of this invention. It is a block diagram which shows the structure of the computer apparatus which performs operation | movement of the one-way regulation determination apparatus of an Example. It is a flowchart which similarly shows operation | movement. The one-way regulation determination result of an Example is shown. The one-way regulation determination result of an Example is shown. The one-way regulation determination result of an Example is shown.

Explanation of symbols

1 link 3 virtual area 5, 6 node 20 one-way regulation judgment device

Claims (6)

Select probe information including coordinate information corresponding to the desired road,
A one-way determination method, comprising: determining one-way restriction on the road based on a distribution of direction information of the selected probe information. 2. The one-way determination method according to claim 1, wherein the step of selecting the probe information includes canceling the probe information that is within a first distance from both end points of the road. The step of selecting the probe information includes selecting a probe that exists within a first width centered on a link indicating the road and that does not exist within a first distance from both end points of the link. The one-way determination method according to claim 1. The method according to claim 3, wherein the coordinate information is map-matched. Means for selecting probe information including coordinate information corresponding to a desired road;
Means for determining one-way restrictions on the road based on a distribution of azimuth information of the selected probe information. A computer program for determining whether or not a road is one-way, the computer selecting means for selecting probe information including coordinate information corresponding to a desired road;
Means for determining one-way regulation on the road based on the distribution of orientation information of the selected probe information;
A computer program that functions as a computer program.

Images