JP2005226999A - Navigation device, map matching method, and navigation program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a navigation device with high map matching precision. <P>SOLUTION: This navigation device comprises a traveling direction detection means (CPU11) which detects a traveling direction of own vehicle, an acquisition means (CPU11) which acquires road links included in a predetermined range including the vehicle position as candidates for map matching, an exception means (CPU11) which traces road links on which the vehicle is expected to be traveling only by a predetermined number from an intersection in the traveling direction of the vehicle and eliminates the road links whose directions are almost opposite to the traversing direction of the vehicle detected by the traveling direction detection means from the candidates acquired by the acquisition means, and a map matching means (CPU11, HDD14) which selects road links from the remainder of the candidates in which certain candidates are eliminated by the exception means and performs a map matching process. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a navigation device, a map matching method, and a navigation program.

  The in-vehicle navigation device receives a signal transmitted from a GPS (Global Positioning Systems) satellite to detect the current position of the own vehicle, and records information about the own vehicle detected by various sensors and a recording device of the navigation device. Based on the recorded map information, the current position of the own vehicle and a road on the map are matched (map matching), and the current position of the own vehicle is displayed on the map displayed on the display unit. When a destination is set, guidance (navigation) to the destination is executed.

  In a conventional navigation device, for example, the connection relationship of road links is analyzed by the method disclosed in Patent Document 1, and based on the analysis result, for example, the distance from the own vehicle by the method disclosed in Patent Document 2, A road link candidate is selected with reference to an angle between the traveling direction and the like, and a road link having the highest possibility of own vehicle is specified from these candidates.

Japanese Patent No. 3289725 (abstract, FIG. 4) JP-A-11-304510 (abstract, FIG. 2)

  For this reason, in the conventional method, processing is executed with all road links that meet the above-described conditions as candidates, so road links that have no possibility that the vehicle is in progress are selected as candidates, and the map is erroneously selected. There is a problem that matching is performed.

  The present invention has been made based on the above circumstances, and an object of the present invention is to provide a navigation device, a map matching method, and a navigation program with high map matching accuracy.

  In order to achieve the above-mentioned object, the navigation device of the present invention acquires a traveling direction detection means for detecting the traveling direction of the host vehicle and road links included in a predetermined range including the host vehicle position as map matching candidates. When a predetermined number of road links are traced from the intersection on the traveling direction side of the own vehicle with respect to the acquisition means and the road link that is predicted to be currently traveling, and the road link is traced among the road links within the traced range The exclusion means for excluding the road link in which the traveling direction of the vehicle is substantially opposite to the traveling direction of the own vehicle by the traveling direction detection means from the candidates acquired by the acquisition means, and the predetermined candidate is determined by the exclusion means Map matching means for selecting a road link from the excluded candidates and executing map matching processing.

  In addition to the above-described invention, in the navigation device of another invention, the exclusion means excludes road links other than those existing in a direction substantially orthogonal to the traveling direction of the vehicle from map matching candidates.

  In addition to the above-described invention, the navigation device according to another invention may include, except for the predetermined number of road links connected to the front or rear of the road link where the vehicle is present, as map matching candidates. I try to exclude it.

  In addition to the above-described invention, the navigation device according to another aspect of the invention may be configured such that the exclusion means has a distance from the own vehicle position equal to or less than a predetermined distance and an angle between the traveling direction of the own vehicle and the predetermined direction. Except for road links that are within an angle, the map matching candidates are excluded.

  Further, the map matching method of the present invention includes a traveling direction detection step for detecting the traveling direction of the host vehicle, an acquisition step for acquiring a road link included in a predetermined range including the host vehicle position as a map matching candidate, A certain number of road links are traced from the intersection in the direction of travel of the vehicle with respect to the road links that are expected to be traveling, and the travel of the vehicle when following the road links among the road links within the tracked range An exclusion step for excluding road links in which the direction and the traveling direction of the vehicle in the traveling direction detection step are approximately opposite to each other from the candidates acquired by the acquisition step, and a remaining candidate from which the predetermined candidates are excluded by the exclusion step A map matching step of selecting a road link from candidates and executing a map matching process.

  The navigation program of the present invention includes a computer, a traveling direction detection unit that detects a traveling direction of the host vehicle, an acquisition unit that acquires a road link included in a predetermined range including the host vehicle position as a map matching candidate, A predetermined number of road links are traced from the intersection on the traveling direction side of the vehicle with respect to the road link that is predicted to be currently traveling, and the road link of the vehicle in the range that has been traced follows the road link. Excluding means for excluding road links in which the traveling direction and the traveling direction of the vehicle by the traveling direction detecting means are substantially opposite from the candidates acquired by the acquiring means, and the predetermined candidates are excluded by the excluding means It is made to function as a map matching means for selecting a road link from the remaining candidates and executing a map matching process.

  The present invention can provide a navigation device, a map matching method, and a navigation program with high mapping accuracy.

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

  FIG. 1 is a block diagram showing a configuration example of a navigation device according to the first embodiment of the present invention. As shown in this figure, the navigation apparatus 10 according to the first embodiment of the present invention includes a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, a RAM (Random Access Memory) 13, an HDD (Hard). Disk Drive) 14, video circuit 15, I / F (Interface) 16, bus 17, LCD (Liquid Crystal Display) 18, input device 19, sensor 20, GPS device 21, and audio output device 22.

  Here, the CPU 11, which is an acquisition unit, an exclusion unit, a part of the map matching unit, and a part of the traveling direction detection unit, performs various arithmetic processes according to programs stored in the HDD 14 or the ROM 12. And a central processing unit that controls each part of the apparatus.

  The ROM 12 is a semiconductor storage device that stores a program executed by the CPU 11. The RAM 13 is a semiconductor storage device that temporarily stores a program executed by the CPU 11.

  The HDD 14 which is a part of the map matching means stores a program executed by the CPU 11 and also stores map information (map display data, road link data, etc.). The video circuit 15 executes a drawing process according to a drawing command supplied from the CPU 11, converts an image obtained as a result of the drawing process into a video signal, and outputs the video signal to the LCD 18.

  The I / F 16 converts and inputs the expression format of signals output from the input device 19, the sensor 20, and the GPS device 21, and converts the expression format of signals output to the audio output device. The bus 17 is a signal line group for mutually connecting the CPU 11, ROM 12, RAM 13, HDD 14, video circuit 15, and I / F 16, and enabling exchange of information among them.

  The LCD 18 is a display device for displaying a video signal output from the video circuit 15. FIG. 2 is a diagram for explaining the details of the LCD 18. As shown in this figure, the LCD 18 has a display unit 18a disposed at the center, and hardware buttons 19b to 19g serving as an input device 19 are disposed around the display unit 18a. Further, since the touch panel 19a as the input device 19 is arranged so as to be superimposed on the display unit 18a, the desired information can be obtained by operating the touch panel 19a with reference to image information displayed on the display unit 18a. Information can be entered. In this example, a map around the current location of the vehicle is displayed on the display unit 18a.

  The icon 30 is an icon imitating a compass and indicates the north-south direction. The icon 30 is used when the map display mode is set to the north-up method (display method in which the north direction is always upward on the map) or the heading-up method (display method in which the traveling direction is always upward on the map). To be operated. The icon 31 is an icon indicating the scale of the currently displayed map information. The icon 31 is operated when changing the scale of the map information. The triangle 32 as a figure indicating the own vehicle position indicates the position and direction of the own vehicle in the map information (the apex above the triangle is the direction of the own vehicle).

  Returning to FIG. 1, as described above, the input device 19 has the touch panel 19 a and the hardware buttons 19 b to 19 g arranged so as to be superimposed on the display unit of the LCD 18, and according to the operation of the operator. Generate and output information.

  The sensor 20 that is a part of the traveling direction detection means includes a vehicle speed sensor that indicates the speed of the vehicle, an angular speed sensor that indicates the angular speed of each control shaft of the vehicle, and a side brake sensor that indicates the operating state of the side brake.

  The GPS device 21 is a device that obtains the current position (latitude, longitude, altitude) of the vehicle using information transmitted from a plurality of GPS artificial satellites. The audio output device 22 performs D / A (Digital to Analog) conversion on the data supplied from the CPU 11 and outputs it as audio.

  Next, an operation related to map matching of the navigation device 10 according to the first embodiment of the present invention will be described. FIG. 3 is a flowchart for explaining the operation related to the matching of the navigation device according to the first embodiment of the present invention. The following operation is realized by the CPU 11 executing the navigation program.

  Step S <b> 10: The CPU 11 acquires the vehicle position calculated from the latitude and longitude acquired by the GPS device 21 and the detection result of the sensor 20.

  Step S11: The CPU 11 acquires from the HDD 14 a road link composed of links and nodes included in a predetermined range including the vehicle position. Specifically, as shown in FIG. 4, when nodes N11 to N16, N21 to N28 and links L11 to L16, L21 to L27 exist, a predetermined area including a triangular vehicle position mark 32 (for example, The links L11 to L16 and L21 to L27 and the nodes N11 to N17 and N21 to N28 included in the area surrounded by a broken line in FIG. 3 are acquired. FIG. 5 shows the road link acquired at this time. In the example of this figure, the area | region enclosed with the broken line shown in FIG. 4 is shown.

  Step S12: The CPU 11 selects a road link located on a line substantially orthogonal to the traveling direction of the host vehicle. Specifically, as shown in FIG. 6, links L12, L15, L23, and L26 that intersect with a line segment 40 that is substantially orthogonal to the traveling direction of the host vehicle are selected.

  Step S13: The CPU 11 selects one of the road links selected in step S12.

  Step S14: The CPU 11 calculates the distance between the road link selected in step S13 and the vehicle position. Specifically, for example, taking the link L23 as an example, as shown in FIG. 7A, a distance D that is the shortest distance between the triangular vehicle position mark 32 and the link L23 is calculated.

  Step S15: The CPU 11 determines whether or not the distance obtained in step S14 is within a predetermined distance. If it is determined that the distance is within the predetermined distance, the CPU 11 proceeds to step S16. Proceed to S21. For example, if the distance D shown in FIG. 7A is within 90 m, the process proceeds to step S16 as being within a predetermined distance, and otherwise the process proceeds to step S21.

  Step S16: The CPU 11 calculates an angle between the traveling direction of the own vehicle and the link selected in step S13. Specifically, as shown in FIG. 7B, an angle α between the traveling direction 45 of the host vehicle and the link L26 is obtained.

  Step S17: The CPU 11 determines whether or not the angle α obtained in step S16 is within a predetermined angle. If the angle α is within the predetermined angle, the process proceeds to step S18. Otherwise, the process proceeds to step S21. move on. For example, when the angle α is within 5 degrees, the process proceeds to step S16, and otherwise, the process proceeds to step S21.

  Step S18: The CPU 11 calculates the traveling direction of the vehicle on the road link selected in step S13. Specifically, when the link is traced in the traveling direction from the link where the current vehicle position exists (that is, the link where the own vehicle position exists before the start of the matching process), the link is selected in step S13. It is determined whether or not the road link can be reached. This link search is performed up to, for example, two links ahead.

  Step S19: The CPU 11 refers to the processing result in step S18, and the traveling direction when the link on the road link selected in step S13 is traced is opposite to the traveling direction when the map matching is performed on the road link. It is determined whether or not the direction is the direction. If the direction is opposite, the process proceeds to step S21. Otherwise, the process proceeds to step S20. As a result, road links whose travel direction of the vehicle after map matching is not appropriate are excluded from candidates. Specifically, as shown in FIG. 8, in the case of the link L15, the link L12 considered to be located at the present time (that is, the link used for the previous matching or the link connected to such a link). ) To the link L15 can be reached. If it is highly possible that the vehicle is currently traveling on the link L12, it is necessary to travel via the link L16 in order to travel on the link L15. Therefore, if the vehicle is traveling on the link L15, the traveling direction of the vehicle must be the downward direction in FIG. 8, and this does not match the current traveling direction. Therefore, such a link L15 is excluded from the comparison target. That is, the road link connected to the junction that joins the currently traveling road link and the other road links connected thereto are excluded from the map matching candidates.

  Step S20: The CPU 11 selects a road link determined to satisfy all the requirements in steps S15, S17, and 19 as a candidate and stores it in the HDD 14.

  Step S21: The CPU 11 determines whether or not there is an unprocessed road link among the road links selected in step S12. If there is, the process returns to step S13 and repeats the same processing. If so, the process proceeds to step S22.

  Step S22: The CPU 11 selects a road link having a high possibility that the host vehicle is located from the road link candidates selected in step S20 and stored in the HDD 14. As a selection method, for example, a link having the shortest distance from the own vehicle and the smallest angle with the traveling direction of the own vehicle is selected.

  In the example shown in FIG. 6, since the link L23 is far from the vehicle position, the link L23 is excluded from the candidates by the process of step S15, and the link L26 has an angle with the traveling direction of the vehicle of a predetermined angle or more. Therefore, the link L15 is excluded from the candidates by the process of step S19, and the link L15 is excluded from the candidates by the process of step S19. As a result, among the candidates selected in step S12, the link L12 remains until the end, so this L12 is used as a road link used for map matching.

  Step S23: The CPU 11 moves the vehicle position with respect to the road link selected in step S22. In the example of FIGS. 6 and 8, the link L12 is selected.

  Step S24: The CPU 11 moves and displays the vehicle position to the position changed in step S23.

  According to the above processing, the selection relation is narrowed down by referring to the connection relation of the road link and considering the predicted traveling direction of the vehicle in each link, so that the map matching to the wrong road link is performed. Can be prevented.

  In the above embodiment, the selection candidate narrowing-down process according to the traveling direction (the processes at steps S18 and S19) is performed as the narrowing-down process regarding the distance from the vehicle position (the processes at steps S14 and S15) and the angle with the traveling direction. This is executed after the narrowing-down process (processes in steps S16 and S17). However, the selection candidate narrowing-down process according to the traveling direction may be executed first. According to such processing, the processing in steps S14 to S17, which has a high processing cost, can be omitted for candidates whose traveling directions are opposite, so that the processing can be speeded up.

  Next, a second embodiment of the present invention will be described. Since the navigation apparatus according to the second embodiment of the present invention has the same configuration as that of FIG. 1, its detailed description is omitted. However, the navigation program stored in the ROM 12 or the HDD 14 is changed to one describing the following operation.

  FIG. 9 is a flowchart for explaining the operation of the navigation apparatus 10 according to the second embodiment of the present invention. In the second embodiment of the present invention, when map matching is executed for two road links before and after the vehicle position, candidates are selected in consideration of the vehicle direction. In this embodiment, when the navigation program is executed by the CPU 11, the following steps are realized.

  Step S <b> 50: The CPU 11 acquires the vehicle position determined from the latitude and longitude acquired by the GPS device 21 and the detection result of the sensor 20.

  Step S51: The CPU 11 acquires a road link where the vehicle is likely to be present, and acquires two road links connected before and after the road link. Specifically, when the road link where the vehicle is likely to be present is the link L13, as shown in FIG. 10, the link L13 and the links L14 and L15 connected in front of the link L13. , Links L19 and L18, and links L12 and L11 connected to the rear of the link L13 are obtained in total.

  Step S52: The CPU 11 selects an arbitrary one from the road links acquired in step S51.

  Step S53: The CPU 11 calculates a traveling direction when the host vehicle travels on the road link acquired in step S52. Specifically, when following a link in the traveling direction of the host vehicle (for example, links L14, L15, L18, L19), the traveling direction is the traveling direction of the link. Further, when the link is traced in the direction opposite to the traveling direction of the host vehicle (for example, the links L11 and L12), the direction opposite to the traveling direction becomes the traveling direction of the host vehicle. As a result, as shown in FIG. 11, the traveling direction of the host vehicle on each link (the direction indicated by the dashed triangle) is obtained.

  Step S54: The CPU 11 determines the Y coordinate (in the vertical direction in the figure) of the node on the bottom side of the triangle (that is, the node on the rear side in the traveling direction among the two nodes in each section) in each link shown in FIG. The value obtained by subtracting the Y coordinate of the node on the apex side of the triangle (that is, the node on the front side in the traveling direction) from the coordinate) and the ends of the link where the own vehicle is likely to be located (link L13 in FIG. 11) If the sign of the value obtained by subtracting the Y coordinate of the node on the vertex side of the triangle from the Y coordinate of the node on the base side of the triangle is different (that is, the traveling direction is different), Advances to step S56, otherwise advances to step S55.

  Step S55: When the traveling direction is the same for the link selected in step S52 and the link that is likely to be present, the CPU 11 registers the link as a candidate in the HDD 14, for example. As a result, the links L18 and L19 that are opposite to the traveling direction of the host vehicle are excluded from the candidates.

  Step S56: The CPU 11 determines whether or not there is an unprocessed road link that is not a target of the processing in steps S52 to S55 among the road links acquired in step S51, and there is an unprocessed road link. If not, the process proceeds to step S57. Otherwise, the process returns to step S52 and the same process is repeated.

  Step S57: The CPU 11 selects a road link used for map matching from the road link candidates stored in the HDD 14 in the process of step S55. Specifically, with reference to an angle between the traveling direction of the own vehicle and the link, a distance between the own vehicle position, and the like, the one with the smallest difference is selected as a correction target.

  Step S58: The CPU 11 changes the vehicle position on the road link selected in step S57.

  Step S59: The CPU 11 moves the vehicle position to the new position changed in step S58.

  According to the above processing, in the map matching process executed to eliminate the error of the vehicle position with respect to the traveling direction, the link in the traveling direction different from the own vehicle is excluded from the candidates in advance. For example, in the example of FIG. 11, the links L18 and L19 can be excluded from the candidates. Therefore, it is possible to prevent the vehicle position from being mapped to an incorrect position. For example, in the example of FIG. 10, there is a high possibility that the vehicle position is mapped to the link L18. However, as described above, the link L18 is excluded from the candidates, so that it is prevented from being erroneously mapped to the link L18. it can.

  Further, according to the above processing, the processing for obtaining the angle and distance performed in step S57 can be omitted by executing the matching processing by previously removing the links L18 and L19 having different traveling directions. The overall processing speed can be improved.

  In the second embodiment described above, two links before and after the vehicle position are acquired. Needless to say, however, one or three or more links may be used.

  Each embodiment described above is a preferred example of the present invention, but the present invention is not limited to these, and various modifications and changes can be made without departing from the scope of the present invention. It is.

  For example, in addition to the angle between the traveling direction of the own vehicle and the road link, a map matching candidate may be selected with reference to the angle of attack of the own vehicle and the angle of attack of the road link.

  Further, when the estimation accuracy of the vehicle position is high, the processing load can be reduced by stopping the map matching process. Further, in the map matching process, the above-described process may be performed only when a plurality of road links are within the same distance from the vehicle position.

  The above processing functions are realized by a computer as shown in FIG. 1, for example. In that case, a program describing the processing contents of the functions that the navigation apparatus should have is provided. By executing the program on the computer, the processing function is realized on the computer. The program describing the processing contents can be recorded on a computer-readable recording medium. Examples of the computer-readable recording medium include a magnetic recording device, an optical disk, a magneto-optical recording medium, and a semiconductor memory. Examples of the magnetic recording device include a hard disk device (HDD), a flexible disk (FD), and a magnetic tape. Examples of the optical disc include a DVD (Digital Versatile Disk), a DVD-RAM (Random Access Memory), a CD-ROM (Compact Disk Read Only Memory), and a CD-R (Recordable) / RW (ReWritable). Magneto-optical recording media include MO (Magneto-Optical disk).

  When distributing the program, for example, portable recording media such as a DVD and a CD-ROM on which the program is recorded are sold. It is also possible to store the program in a storage device of a server computer and transfer the program from the server computer to another computer via a network.

  The computer that executes the program stores, for example, the program recorded on the portable recording medium or the program transferred from the server computer in its own storage device. Then, the computer reads the program from its own storage device and executes processing according to the program. The computer can also read the program directly from the portable recording medium and execute processing according to the program. Further, each time the program is transferred from the server computer, the computer can sequentially execute processing according to the received program.

  The present invention can be used for a navigation apparatus using a map matching process.

It is a block diagram which shows the structural example of the navigation apparatus which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating an example of the screen displayed on LCD of 1st Embodiment shown in FIG. In the 1st Embodiment of this invention, it is a flowchart for demonstrating an example of the process which changes the own vehicle position. It is a flowchart for demonstrating the detail of the process which acquires a road link in step S11 shown in FIG. It is a figure which shows an example of the road link acquired in step S11 shown in FIG. FIG. 4 is a flowchart for explaining details of a process of selecting a road link in step S12 shown in FIG. In the 1st Embodiment of this invention, it is a figure for demonstrating the detail of the process which selects a road link, (A) is a figure which shows the distance between the own vehicles, (B) is an own vehicle. It is a figure which shows an angle with the advancing direction. In the 1st Embodiment of this invention, it is a figure which shows the link different from the advancing direction of the own vehicle. In the 2nd Embodiment of this invention, it is a flowchart for demonstrating an example of the process which changes the own vehicle position. It is a figure which shows the road link used as the object of the process of the flowchart shown in FIG. It is a figure which shows the traveling direction on each road link calculated in the flowchart shown in FIG.

Explanation of symbols

10 navigation device 11 CPU (acquisition means, exclusion means, part of map matching means, part of traveling direction detection means)
14 HDD (part of map matching means)
20 sensor (part of traveling direction detection means)

Claims (6)

In the navigation device that displays the vehicle position on the display unit,
Traveling direction detection means for detecting the traveling direction of the host vehicle;
Acquisition means for acquiring road links included in a predetermined range including the vehicle position as map matching candidates;
A predetermined number of road links are traced from the intersection on the traveling direction side of the vehicle with respect to the road link that is predicted to be currently running, and the road link of the vehicle in the range that has been traced follows the road link. Exclusion means for excluding road links in which the traveling direction and the traveling direction of the vehicle by the traveling direction detection means are substantially opposite from the candidates obtained by the obtaining means,
Map matching means for selecting a road link from the remaining candidates from which the predetermined candidates are excluded by the exclusion means and executing map matching processing;
A navigation device comprising:   The navigation device according to claim 1, wherein the excluding means excludes from the map matching candidates other than road links existing in a direction substantially orthogonal to the traveling direction of the host vehicle.   2. The navigation apparatus according to claim 1, wherein the excluding means excludes from the map matching candidates other than a predetermined number of road links respectively connected to the front or rear of the road link where the own vehicle exists.   The excluding means excludes from the map matching candidates other than road links whose distance from the vehicle position is equal to or less than a predetermined distance and whose angle with the traveling direction of the vehicle is within a predetermined angle. The navigation device according to claim 1. In the map matching method of the navigation device that displays the vehicle position on the display unit,
A traveling direction detection step for detecting the traveling direction of the host vehicle;
An acquisition step of acquiring road links included in a predetermined range including the vehicle position as map matching candidates;
A predetermined number of road links are traced from the intersection on the traveling direction side of the vehicle with respect to the road link that is predicted to be currently running, and the road link of the vehicle in the range that has been traced follows the road link. An exclusion step of excluding road links in which the traveling direction and the traveling direction of the vehicle in the traveling direction detection step are substantially opposite from the candidates acquired by the acquiring step;
A map matching step of selecting a road link from the remaining candidates from which the predetermined candidates are excluded by the exclusion step and executing a map matching process;
A map matching method characterized by comprising: In a computer-readable navigation program executed in a navigation device that displays the vehicle position on a display unit,
Computer
Traveling direction detection means for detecting the traveling direction of the host vehicle,
An acquisition means for acquiring a road link included in a predetermined range including the vehicle position as a map matching candidate;
A predetermined number of road links are traced from the intersection on the traveling direction side of the vehicle with respect to the road link that is predicted to be currently running, and the road link of the vehicle in the range that has been traced follows the road link. Excluding means for excluding road links in which the traveling direction and the traveling direction of the vehicle by the traveling direction detecting means are substantially opposite from the candidates acquired by the acquiring means, and
Map matching means for selecting a road link from the remaining candidates from which the predetermined candidates are excluded by the exclusion means and executing map matching processing;
A computer-readable navigation program that functions as a computer program.

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