JP2015175690A - Position determining device, position determining method, and position determining program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine a present position of a moving body by processing with a low load, on the basis of a photographic image of a camera mounted on the moving body.SOLUTION: A position determining device detects objects on a road with the movement of a moving body, and calculates an interval between the detected objects. With the movement of the moving body, a plurality of objects is detected, and intervals of those are calculated. On the other hand, intervals on a map are stored in a memory portion. The position determining device determines a position of the moving body, on the basis of the intervals of the objects calculated with the movement of the moving body, and the intervals of the objects stored in the memory portion.

Description

  The present invention relates to a method for determining the position of a moving body.

  Conventionally, a mobile navigation device or the like uses GPS as a position specifying technique. However, GPS usually has a positioning error of several meters to several tens of meters. As a technique for correcting the error, Patent Documents 1 and 2 have been proposed.

  Patent Document 1 uses a vehicle-mounted camera to capture a scene that can be seen from a driver's seat. It is determined whether or not there is a road sign in the image taken by image analysis, and a feature point of the road sign in the image is extracted. Then, the coordinates of the feature points are calculated based on the vehicle, and the current position is calculated based on the calculated coordinates of the feature points and the position coordinates of the feature points in the road marking information DB.

  In Patent Document 2, reference data obtained by extracting feature points of a landscape image photographed by a vehicle-mounted camera is stored in a database, and a matching process between the landscape image photographed from the vehicle-mounted camera and the reference data is performed. The host vehicle position is determined based on the shooting position corresponding to the reference data determined to match by the matching process.

JP 2007-1080431 A JP 2013-32953 A

  In the method of the above-mentioned patent document, processing such as shooting, image analysis, extraction of a feature from an image, calculation of position information from the feature, correction of the current position, etc. must always be performed while the moving body is traveling. Therefore, the processing load is heavy. In general, there are characteristic features to be noticed during traveling in a wide range such as those immediately in front of a moving body, those far away, those near the ground or on the side of the road, and those that are overhead. In particular, since road signs are on the side of the road or at high places, it is necessary to widen the viewing angle of the shooting range of the camera. Naturally, the captured image covers the scenery from the driver's seat widely, increasing the amount of information and increasing the image processing load.

  Further, if it takes time for image analysis and the moving body moves during that time, the calculated position and the actual current position are shifted, making it difficult to accurately determine the current position. Furthermore, it is necessary to prepare a database of position information corresponding to the feature object in the terminal or in the server, and it takes much labor to construct the database.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to determine the current position of a moving object based on a photographed image of a camera mounted on the moving object by processing with a small load. And

  The invention described in the claims is a position determination device, which sequentially detects an object on a road on which a moving body moves according to the movement of the moving body, and sequentially calculates an interval between the objects. A calculation unit; and a determination unit that determines a position of the moving body based on an interval calculated by the calculation unit and an interval between objects on a map stored in a storage unit. To do.

  The invention described in another claim is a position determination method executed by the position determination device, and a detection step of sequentially detecting an object on a road on which the moving body moves according to the movement of the moving body; Determination of determining the position of the moving body based on a calculation step of sequentially calculating the interval between the objects, the interval calculated by the calculation means, and the interval between the objects on the map stored in the storage unit And a process.

  The invention described in another claim is a position determination program executed by a position determination device including a storage unit and a computer, and sequentially selects an object on a road on which the moving body moves according to the movement of the moving body. Based on the detection means for detecting, the calculation means for sequentially calculating the interval between the objects, the interval calculated by the calculation means, and the distance between the objects on the map stored in the storage unit, The computer is caused to function as determination means for determining a position.

1 shows a configuration of a navigation device according to an embodiment. It is a figure explaining the method of detecting the mark on a road. It is a figure explaining the detection window for detecting a white line. It is a figure explaining the detection window for detecting a traffic light. An example of the position of the white line on the road is shown. The example of the memory content of a mark interval database is shown. It is an example of mark interval measurement data. It is a flowchart of a mark space | interval measurement process. It is a flowchart of a position determination process.

  In a preferred embodiment of the present invention, the position determination device includes a detection unit that sequentially detects an object on a road on which the moving body moves according to the movement of the moving body, and a calculation that sequentially calculates an interval between the objects. Means for determining the position of the moving body based on the interval calculated by the calculation unit and the interval between the objects on the map stored in the storage unit.

  Said position determination apparatus detects the target object on a road with the movement of a mobile body, and calculates the space | interval of the detected target object. An object is a mark such as a white line on a road, a traffic light, or the like. As the moving object moves, a plurality of objects are detected, and the intervals are calculated. On the other hand, the interval between objects on the map is stored in the storage unit. The position determination device determines the position of the moving body based on the interval between the objects calculated as the moving body moves and the interval between the objects stored in the storage unit. Thereby, the position of a moving body can be determined by collating the detected space | interval of the target object with the space | interval memorize | stored in the memory | storage part.

  In one aspect of the above-described position determination device, the detection unit includes: an imaging unit that captures an image of the front of the moving body to generate a captured image; Extracting means for analyzing and extracting the object, wherein the extracting means changes the detection area according to the speed of the moving body. In this aspect, the detection accuracy of the object is ensured by changing the detection region in accordance with the speed of the moving body.

  In another aspect of the above-described position determination device, the determination unit does not use the interval calculated when the moving body changes direction in the determination. When the moving body changes direction, such as turning right or left, the calculation accuracy of the distance between the objects decreases, so the calculated distance is not used for position determination. Prevent decline.

  In a preferred example, the object is a display of a white line drawn on a road surface, the detection unit detects the display of the white line, and the calculation unit calculates an interval of the white line display detected by the detection unit. .

  In another preferred example, the object is a traffic light, the detection means detects the traffic light, and the calculation means calculates an interval of the traffic light detected by the detection means.

  In another preferred embodiment of the present invention, the position determination method executed by the position determination device includes a detection step of sequentially detecting an object on a road on which the moving body moves according to the movement of the moving body, A calculation step of sequentially calculating an interval between objects, a determination step of determining the position of the moving body based on the interval calculated by the calculation means and the interval between objects on a map stored in a storage unit And comprising. Also by this method, the position of the moving body can be determined by comparing the detected interval between the objects with the interval stored in the storage unit.

  In another preferred embodiment of the present invention, a position determination program executed by a position determination device including a storage unit and a computer sequentially detects an object on a road on which the moving body moves according to the movement of the moving body. Detecting means, calculating means for sequentially calculating the interval of the object, the position calculated by the calculating means, and the position of the moving object based on the interval of the object on the map stored in the storage unit The computer is caused to function as a determination means for determining whether or not. By executing this program on a computer, the position determination device described above can be realized.

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

[Device configuration]
FIG. 1 shows a schematic configuration of a navigation apparatus according to an embodiment of the position determination apparatus of the present invention. As shown in FIG. 1, the navigation device 1 includes a self-supporting positioning device 10, a GPS receiver 18, a system controller 20, a camera 31, a data storage unit 36, a communication interface 37, a communication device 38, a display unit 40, and an audio output unit. 50, an input device 60 is provided.

  The system controller 20, the camera 31, the data storage unit 36, the communication interface 37, the display unit 40, the audio output unit 50, and the input device 60 are connected to each other via the bus line 30.

  The autonomous positioning device 10 includes an acceleration sensor 11, an angular velocity sensor 12, and a distance sensor 13. The acceleration sensor 11 is made of, for example, a piezoelectric element, detects vehicle acceleration, and outputs acceleration data. The angular velocity sensor 12 is composed of, for example, a vibrating gyroscope, detects the angular velocity of the vehicle when the direction of the vehicle is changed, and outputs angular velocity data and relative azimuth data. The distance sensor 13 measures a vehicle speed pulse composed of a pulse signal generated with the rotation of the vehicle wheel.

  The GPS receiver 18 receives radio waves 19 carrying downlink data including positioning data from a plurality of GPS satellites. The positioning data is used to detect the absolute position of the vehicle (hereinafter also referred to as “current position”) from latitude and longitude information.

  The system controller 20 includes an interface 21, a CPU (Central Processing Unit) 22, a ROM (Read Only Memory) 23, and a RAM (Random Access Memory) 24, and controls the entire navigation apparatus 1.

  The interface 21 performs interface operations with the acceleration sensor 11, the angular velocity sensor 12, the distance sensor 13, and the GPS receiver 18. From these, vehicle speed pulses, acceleration data, relative azimuth data, angular velocity data, GPS positioning data, absolute azimuth data, and the like are input to the system controller 20.

  The CPU 22 controls the entire system controller 20. The ROM 23 includes a nonvolatile memory (not shown) in which a control program for controlling the system controller 20 is stored. The RAM 24 stores various data such as route data preset by the user via the input device 60 so as to be readable, and provides a working area to the CPU 22.

  The camera 31 captures and records a landscape in front of the vehicle. The captured image data is stored in the data storage unit 36.

  The data storage unit 36 includes, for example, an HDD, a flash memory, and the like, and stores various data used for navigation processing such as map data. The communication device 38 performs wireless communication with the server 7 via the network. The communication device 38 may be a dedicated wireless communication unit built in the navigation device 1, and is a unit that connects to a mobile phone by wire or wirelessly and connects to a network using the communication function of the mobile phone. There may be.

  The display unit 40 displays various display data on a display device such as a display under the control of the system controller 20. Specifically, the system controller 20 reads map data from the data storage unit 36. The display unit 40 displays the map data read from the data storage unit 36 by the system controller 20 on the display screen. The display unit 40 includes a graphic controller 41 that controls the entire display unit 40 based on control data sent from the CPU 22 via the bus line 30 and a memory such as a VRAM (Video RAM), and can display image information that can be displayed immediately. A buffer memory 42 that temporarily stores, a display control unit 43 that controls display of a display 44 such as a liquid crystal display or a CRT (Cathode Ray Tube) based on image data output from the graphic controller 41, and a display 44 are provided. . The display 44 functions as an image display unit, and includes, for example, a liquid crystal display device having a diagonal of about 5 to 10 inches and is mounted near the front panel in the vehicle.

  The audio output unit 50 is a D / A converter 51 that performs D / A (Digital to Analog) conversion of audio digital data sent from the drive device (not shown) or the RAM 24 via the bus line 30 under the control of the system controller 20. , An amplifier (AMP) 52 that amplifies the audio analog signal output from the D / A converter 51, and a speaker 53 that converts the amplified audio analog signal into sound and outputs the sound into the vehicle.

  The input device 60 includes keys, switches, buttons, a remote controller, a voice input device, and the like for inputting various commands and data. The input device 60 is disposed around the front panel and the display 44 of the main body of the in-vehicle electronic system mounted in the vehicle. When the display 44 is a touch panel system, the touch panel provided on the display screen of the display 44 also functions as the input device 60.

  In the above configuration, the camera 31 is an example of the photographing unit of the present invention, the data storage unit 36 is an example of the storage unit of the present invention, and the CPU 22 is a detection unit, a calculation unit, an extraction unit, and a determination unit of the present invention. It is an example.

[Method of position determination]
Next, a position determination method in the present embodiment will be described. In the present embodiment, the system controller 20 of the navigation device 1 detects a mark on the road from an image taken by the camera 31, and the interval between the detected marks (hereinafter referred to as “marking interval”). Is calculated. As the mark, for example, a white line on the road, road paint (for example, white or yellow paint such as “Stop” character), a traffic light, or the like can be used. The mark is an example of the object of the present invention.

  On the other hand, the actual intervals of such landmarks are acquired in advance by map data or field surveys, etc., and are stored in a landmark interval database (hereinafter, “database” is referred to as “DB”). The current position of the navigation device 1 is determined by comparing the mark interval calculated based on the mark detected from the photographed image of the camera 31 with the mark interval stored in advance in the mark interval DB.

  FIG. 2 shows how a landmark on the road is detected. On the road 3, there are a white line 4 as an example of a landmark and a traffic light 5 as another example. In the following description, the white line 4 is used as a mark. The vehicle 2 is equipped with a navigation device 1. A camera 31 attached to the front of the vehicle 2 captures a scene in front of the vehicle 2 while the vehicle 2 is traveling.

  FIG. 3 shows an example of a photographed image in front of the vehicle 2 by the camera 31. Specifically, FIG. 3A shows a photographed image when the vehicle 2 is at the point A shown in FIG. 2, and FIG. 3B shows a photographed image when the vehicle 2 is at the point B shown in FIG. FIG. 3C shows an example of a photographed image when the vehicle 2 is at the point C shown in FIG.

  The system controller 20 detects a white line from the captured image. At this time, as understood from FIG. 3, the white line is painted on the road, so the white line in the captured image moves from the vicinity of the center of the captured image to the lower end of the captured image as the vehicle advances. Moving. Therefore, as shown in FIG. 3, the system controller 20 provides the detection window 7 at the lower end of the captured image, and detects the presence or absence of a white line within the range. Specifically, the system controller 20 determines that one white line 4 has been detected when the white line 4 enters the detection window 7, passes through the detection window 7, and falls downward. In this way, the system controller 20 detects the white line 4 every time the vehicle 2 passes the white line 4 on the road. The detection window 7 is an example of the detection region of the present invention.

  Usually, the road is asphalt pavement or the like, and the color is close to black. On the other hand, the white line 4 is white paint, so that the process of detecting the white line 4 from the road in the captured image can be performed by a simple binarization process. it can. Therefore, an inexpensive monochrome camera can be used as the camera 31, or a sensor can be used instead of the camera 31. Further, the image analysis for detecting the white line 4 need only be performed on a part of the captured image in the vicinity of the detection window 7, so that the processing is performed in comparison with the image analysis as in Patent Documents 1 and 2. There is an advantage that the load can be reduced.

  It is preferable to adjust the vertical width of the detection window 7 used for detecting the white line 4 according to the traveling speed of the vehicle 2. For example, when the traveling speed is equal to or lower than a predetermined speed, the vertical width of the detection window 7 is set as the reference width, and when the traveling speed increases, the vertical width of the detection window 7 is increased accordingly. Thereby, the detection accuracy of the white line 4 can be maintained.

  The system controller 20 detects the white line 4 in order while the vehicle 2 is traveling, and acquires the travel distance from the detection of one white line 4 to the detection of the next white line 4, that is, the interval between two consecutive white lines. . Specifically, the system controller 20 calculates the interval between the white lines 4 by counting the vehicle speed pulses output from the distance sensor 13 and stores them in the RAM 24 and the sequential data storage unit 36.

  FIG. 4 shows an example of a photographed image when the traffic light 5 is used as a mark. Specifically, FIG. 4A shows a photographed image when the vehicle 2 is at point A shown in FIG. 2, and FIG. 4B shows a photographed image when the vehicle 2 is at point B shown in FIG. FIG. 4C shows an example of a photographed image when the vehicle 2 is at point C shown in FIG.

  As understood from FIG. 4, as the vehicle 2 travels, the traffic light 5 moves from the vicinity of the center in the vertical direction of the captured image to the upper end. Therefore, when the traffic light 5 is used as a mark, the system controller 20 sets the detection window 7 near the upper end of the photographed image as shown in FIG. 4, and the traffic light 5 enters the detection window 7 from below and goes upward. It is determined that the traffic light 5 has been detected.

  As a mark, in addition to the white line and the traffic light, an arrow mark painted on the road, characters such as “stop”, a speed limit number, and the like may be used. Specifically, the system controller 20 can store these marks, characters, numbers, and the like as shape patterns and detect them by matching processing with respect to a captured image. Further, not only white paint but also yellow paint may be targeted. In this way, by using an easily recognizable object such as a traffic light or road paint as a mark, the mark can be easily recognized even in bad weather conditions such as rainy weather.

  Next, an example of the mark interval will be described. FIG. 5 shows an example of a certain road. In FIG. 5, a horizontal road 73 and a vertical road 74 intersect each other. The road 73 has white lines 4 as landmarks at points A to G. The road 74 has white lines 4 as landmarks at points HL. Points D, E, I, and J belong to the intersection of the road 73 and the road 74.

  FIG. 6 shows an example of data stored in the landmark interval DB for the road of FIG. In the mark interval DB, “section” indicates a road section defined by adjacent points. “Position” indicates the position coordinates of each point defining the section. The “interval” indicates the distance between two points that define the section, that is, the distance between the white lines 4 at the two points. The “intersection flag” is a flag indicating whether or not the section belongs to the intersection. In a section belonging to an intersection, a number indicating the intersection is stored as an intersection flag. In the example of FIG. 5, since the section D-E and the section I-J belong to the intersection, an intersection flag is stored. On the other hand, the intersection flag is not stored in the section that does not belong to the intersection. The mark interval DB as shown in FIG. 6 is prepared based on the map data and the field survey, and is stored in the data storage unit 36 of FIG. The landmark interval DB is basically stored in the server, and may be downloaded from the server and stored in the data storage unit 36 as necessary.

  Next, FIG. 7 shows an example of mark interval measurement data measured by the navigation device 1 when the vehicle 2 is traveling. FIG. 7A shows mark interval measurement data obtained when the vehicle 2 travels along the route 1 shown in FIG. The measured mark interval is stored for each section from the section AB to the section FG. The “direction change flag” indicates whether or not the vehicle 2 has changed direction, that is, has made a right or left turn during traveling in the section. In the route 1, the vehicle 2 does not change direction, so the direction change flag is not stored.

  FIG. 7B shows the mark interval measurement data obtained when the vehicle travels along the route 2 shown in FIG. Similarly to FIG. 7A, the mark interval measured for each section is stored. However, in the route 2, since the vehicle 2 is changing direction (turning left) in the section DI belonging to the intersection, the direction change flag “present” is stored for the section DI. Further, the mark interval is not stored for the section DI in which the direction is changed. This is because the mark interval measured at the time of turning tends to have a large error, and is unsuitable for use in position determination described later. Note that whether or not the vehicle 2 has changed direction can be determined based on, for example, the output of the angular velocity sensor 12 of the navigation device 1.

  Next, a specific method for position determination will be described. For example, consider a case where the vehicle 2 travels from point A to point D along route 1 shown in FIG. Here, it is assumed that the system controller 20 does not know which section of which road the vehicle 2 is traveling. In this case, as shown in FIG. 7A, the system controller 20 obtains “35 m”, “25 m”, and “17 m” in order as the measured mark intervals. Based on this, the system controller 20 refers to the mark interval DB illustrated in FIG. 6 and searches for a section in which the mark interval changes in the order of “35 m → 25 m → 17 m”. In the example of FIG. 6, the interval AB is stored as “35 m”, the interval BC is “25 m”, and the interval CD is “17 m” in the mark interval DB. Therefore, the system controller 20 determines that the vehicle 2 is currently traveling in the section A-D.

  Since the mark interval for a large number of sections is stored in the mark interval DB, the mark interval may change from “35 m → 25 m → 17 m” in another section other than the section AD. Now, it is assumed that such a section is “section SV”. In that case, the system controller 20 will extract the sections AD and SV as sections in which the mark interval changes from “35 m → 25 m → 17 m”. It is not possible to decide which is the case.

  In this case, the system controller 20 further performs determination by adding the next section. That is, the mark interval “20 m” of the next section DE is acquired from the mark interval measurement data shown in FIG. 7A, and the mark interval is “35 m → 25 m → 17 m → 20 m” with reference to the mark interval DB. Find the transition section. As long as the mark interval of the next section of the section SV is not 20 m, the system controller 20 can determine that the currently traveling section is the section AE. Thus, when there are a plurality of sections in the mark interval DB that match the transition pattern of the mark interval measurement data, the mark interval of the next section is further added until the number of matching sections becomes one. What is necessary is just to compare with the memory content.

  As described above, the system controller 20 searches the mark interval DB for a section having a pattern that matches the transition pattern of successive mark intervals in the mark interval measurement data, and sets the section corresponding to the pattern as the current position of the vehicle 2. Can be determined.

  On the other hand, as in the example of the route 2 shown in FIG. 7B, when the mark interval measurement data includes an intersection section (that is, a section where the direction change flag is “present”), the mark interval for that section is included. Instead, the section may be compared as an “intersection” instead.

  Specifically, when the mark interval measurement data shown in FIG. 7B is obtained, the system controller 20 sets the interval in which the mark interval changes from “35 m → 25 m → 17 m → intersection → 30 m” as the mark interval. Search by DB. As shown in FIG. 6, in the mark interval DB, the section belonging to the intersection is given an intersection flag, and it can be seen that the section DE and the section I-J belong to the same intersection (No. 253). The system controller 20 sets “section AB → section BC → section CD → intersection (No. 253) → section H as a section where the mark interval changes from“ 35 m → 25 m → 17 m → intersection → 30 m ”. -J "can be found. Thereby, the system controller 20 can determine that the vehicle 2 travels in the section A-D, turns around the intersection, and enters the section I-H (that is, the vehicle is in the section HI).

  In addition, when the section where the vehicle turns is included in the mark interval measurement data, it is possible to determine the position by considering the intersection as described above, but the processing is complicated compared to the case where the intersection is not included. Become. Therefore, the position determination including the section where the vehicle has changed direction may not be performed from the beginning. That is, the current position of the vehicle 2 may be determined by comparing the mark intervals of a plurality of consecutive sections in which the vehicle has not changed its direction with the mark interval DB.

  As described above, according to the present embodiment, the current pattern of the vehicle 2 can be obtained by comparing the transition pattern of the mark interval measured during traveling with the transition pattern of the mark interval stored in advance in the mark interval DB. The position can be determined. That is, a section having a transition pattern that matches the transition pattern of the mark interval measured during traveling can be determined as the current position.

  In the above description, the system controller 20 does not know the current position of the vehicle 2 and determines the current position of the vehicle 2 based on the mark interval obtained during traveling. This method can be used as an alternative method when GPS positioning cannot be performed due to deterioration of the radio wave environment or malfunction of a device such as a GPS sensor. On the other hand, even in a situation where GPS positioning is possible, the determination result based on the mark interval may be used for correcting the current position obtained by GPS positioning.

  In the above example, the white line 4 is used as the mark. However, when using another mark, the mark interval for the mark may be measured and compared with the mark interval stored in the database. For example, when using the traffic light 5 as a landmark, the system controller 20 measures the interval of the traffic signal 5 as the landmark interval, and determines the current position by the same method as described above with reference to the landmark interval DB storing the interval of the traffic signal 5 do it.

[Processing flow]
Next, processing executed in this embodiment will be described. In the present embodiment, a mark interval measurement process for measuring the mark interval while the vehicle 2 is traveling and a position determination process for determining the current position by referring to the mark interval DB using the mark interval obtained by the measurement are performed. Is called.

  First, the mark interval measurement process will be described. FIG. 8 is a flowchart of the mark interval measurement process. This process is performed by the CPU 22 of the system controller 20 executing a program prepared in advance.

  First, the CPU 22 receives designation of a mark by the user and sets the detection window 7 (step S10). For example, when the user designates a white line as a mark, the CPU 22 sets the detection window 7 at the lower end of the captured image as shown in FIG. Then, the CPU 22 controls the camera 31 to start photographing (Step S11).

  When shooting is started, the CPU 22 detects a mark from the shot image by the method described with reference to FIG. 3 (step S12). When the mark is detected (step S12: Yes), the CPU 22 calculates the distance from the previous mark and stores it as the mark interval (step S13). Step S13 is not performed when the first mark is detected.

  Next, the CPU 22 determines whether or not the vehicle has stopped (step S14). If the vehicle is not stopped (step S14: No), the process returns to step S12. Therefore, the mark interval is calculated and stored every time the next mark is detected until the vehicle stops. The mark interval calculated in this way is stored as mark interval measurement data as shown in FIG. On the other hand, when the vehicle stops (step S14: Yes), the process ends.

  Next, the position determination process will be described. FIG. 9 is a flowchart of the position determination process. This process is also performed by the CPU 22 executing a program prepared in advance.

  First, the CPU 22 reads one mark interval in the mark interval measurement data illustrated in FIG. 7 (step S21), and refers to the mark interval DB to determine whether there is a mark interval that matches the mark interval. (Step S22). For example, in the example of FIG. 7A, the CPU 22 reads the mark interval “35 m” and determines whether or not there is a section with the mark interval “35 m” in the mark interval DB.

  If there is no matching mark interval (step S22: No), the process returns to step S21, and the CPU 22 reads the next mark interval. On the other hand, if there is a matching mark interval (step S22: Yes), the CPU 22 reads the next mark interval (step S23) and refers to the mark interval DB to determine whether there is a section that also matches the next mark interval. Determine. Specifically, in the example of FIG. 7 a), the CPU 22 reads the next mark interval “25 m” and determines whether there is a mark interval that matches this. That is, at this time, the CPU 22 determines whether or not there is a pattern in the mark interval DB that matches the transition pattern of the mark interval “35 m → 25 m”. Hereinafter, a section in the mark interval DB having a pattern that matches the transition pattern of the mark interval in the mark interval measurement data is also referred to as “DB candidate”.

  If the next mark interval does not match (step S24: No), the process returns to step S21. In this case, since the corresponding transition pattern does not exist in the mark interval DB, the process is performed again using another mark interval measurement data.

  On the other hand, when the next mark interval matches (step S24: Yes), the CPU 22 determines whether there is one DB candidate that also matches the next mark interval in the mark interval DB (step S25). . That is, the CPU 22 determines whether there is one or a plurality of transition patterns of the mark interval “35 m → 25 m” existing in the mark interval DB.

  When the number of candidates in the DB is not one (step S25: No), that is, when there are a plurality of transition patterns of the mark interval “35 m → 25 m” in the mark interval DB, the process returns to step S23, and the CPU 22 further determines the next mark. The interval is read, and it is determined whether or not there is a candidate in the DB that matches the mark interval in the mark interval DB. In this way, the CPU 22 adds the next landmark interval and compares the transition patterns until there is only one candidate in the DB that matches the transition pattern of the landmark interval in the landmark interval DB.

  When the number of candidates in the DB that match the pattern of the mark intervals is one (step S25: Yes), the CPU 22 determines the section of the candidates in the DB as the current position (step S26), and ends the position determination process. .

[Modification]
In the above embodiment, the match between the mark interval obtained during traveling and the mark interval stored in the mark interval DB is determined. However, the mark interval actually obtained during running has some error. Often included. Therefore, it is possible to allow a difference within a predetermined error range (for example, 10%) and perform a match determination.

  In the above embodiment, the present invention is applied to a vehicle-mounted navigation device, but can be similarly applied to a navigation device for pedestrians and bicycles. Further, it can be applied to a map display application in a mobile terminal such as a smartphone.

DESCRIPTION OF SYMBOLS 1 Navigation apparatus 2 Vehicle 3 Road 4 White line 5 Traffic light 7 Detection window 20 System controller 22 CPU
31 Camera

Claims (7)

Detecting means for sequentially detecting an object on a road on which the moving body moves according to the movement of the moving body;
A calculation means for sequentially calculating an interval between the objects;
A determination unit that determines the position of the moving body based on the interval calculated by the calculation unit and the interval between the objects on the map stored in the storage unit;
A position determination apparatus comprising: The detection means includes
Photographing means for photographing the front of the moving body to generate a photographed image;
Extraction means for analyzing the captured image in a detection area set in a part of the captured image and extracting the object;
The position determination apparatus according to claim 1, wherein the extraction unit changes the detection area according to a speed of the moving body.   The position determination apparatus according to claim 1, wherein the determination unit does not use an interval calculated when the moving body changes direction in determination. The object is an indication of a white line drawn on the road surface,
The detecting means detects the display of the white line;
The position determination apparatus according to claim 1, wherein the calculation unit calculates a display interval of white lines detected by the detection unit. The object is a traffic light;
The detecting means detects the traffic light;
The position determination apparatus according to claim 1, wherein the calculation unit calculates an interval between traffic lights detected by the detection unit. A position determination method executed by a position determination device,
A detection step of sequentially detecting an object on a road on which the moving body moves according to the movement of the moving body;
A calculation step of sequentially calculating an interval between the objects;
A determination step of determining the position of the moving body based on the interval calculated by the calculation means and the interval between the objects on the map stored in the storage unit;
A position determination method comprising: A position determination program executed by a position determination device including a storage unit and a computer,
Detecting means for sequentially detecting an object on a road on which the moving body moves according to the movement of the moving body;
A calculation means for sequentially calculating an interval between the objects;
Determination means for determining the position of the moving body based on the interval calculated by the calculation means and the interval between objects on the map stored in the storage unit;
A position determination program that causes the computer to function as: