JP3607159B2 - Navigation system, map matching method, and recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a navigation system that synthesizes and displays a symbol indicating a vehicle position on a map image, and in particular a navigation system capable of appropriately correcting the vehicle position on a running road, a map matching method, and The present invention relates to a recording medium.
[0002]
[Prior art]
A conventional navigation system is mounted on a user's vehicle (hereinafter referred to as “own vehicle”), receives satellite radio waves from a predetermined GPS (Global Positioning System) unit or the like, and receives the current position of the vehicle (own vehicle). Position). Then, a map image or the like centered on the vehicle position is read from a disk or the like on which map information including map image and road information is recorded, and a map image in which a symbol indicating the vehicle position is synthesized is displayed on a predetermined monitor. .
By referring to the map image and the vehicle position displayed on the monitor, the user recognizes the positional relationship between the vehicle he / she is driving and the surrounding roads, and can automatically move to the destination to be headed without getting lost. You can drive the car.
[0003]
As described above, such navigation systems generally use satellite navigation in which a satellite radio wave transmitted from a GPS satellite is received by a GPS unit or the like and the position of the vehicle is calculated according to the received satellite radio wave. This satellite navigation is normally expected to have an error of about several tens of meters. In addition, in satellite navigation, a larger error may occur due to the influence of the position of the receivable satellite (satellite arrangement, etc.) and the buildings around the vehicle.
For this reason, if the own vehicle position obtained by satellite navigation is used as it is and a symbol is synthesized at the corresponding position on the map image, the symbol may not be located on the road due to an error that occurs.
[0004]
As a countermeasure against this, many navigation systems are provided with a map matching function that corrects the position of the vehicle so as to be located on the target road. The map matching function appropriately corrects the position of the vehicle on the map image so as to be positioned on a nearby road in anticipation of an error that has occurred by using, for example, a pattern matching method or a projection method.
Since the navigation system having such a map matching function displays a map image in which symbols are synthesized on a predetermined road, it is possible to indicate a destination to be headed without causing confusion to the user.
[0005]
[Problems to be solved by the invention]
However, in the conventional navigation system, the vehicle position after map matching may not be corrected correctly on the road on which the vehicle is traveling.
Specifically, in a state where the vehicle is traveling in an area where the expressway and the general road overlap with each other due to an overpass or the like, or the vehicle is traveling in parallel, the navigation system determines which road the vehicle is in. Since it is not possible to accurately determine whether the vehicle is traveling, the vehicle position may be corrected on an incorrect road by map matching.
[0006]
For example, even when the host vehicle is traveling on an elevated highway, the navigation system may correct the position of the host vehicle on a general road under the elevated by map matching. In this case, the navigation system misrecognizes that the host vehicle is traveling on a general road, and instructs a right or left turn that is impossible in practice.
If such an incorrect instruction is given, the user is surprised at an unexpected instruction and may make a mistake in driving operation, which is extremely dangerous.
[0007]
The present invention has been made in view of the above circumstances, and navigation capable of appropriately correcting the vehicle position on the traveling road when a symbol indicating the vehicle position is combined and displayed on a map image. It is an object to provide a system, a map matching method, and a recording medium.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a navigation system according to the first aspect of the present invention provides:
An imaging unit that captures a landscape image of the vehicle traveling direction including the road surface;
An image analysis unit that extracts a lane image drawn on a road surface from a landscape image at a time that is imaged by the imaging unit and measured by a predetermined timer;
A travel distance calculation unit that calculates a travel distance of the vehicle that traveled between the reference screen and the predetermined screen according to the output of the vehicle speed pulse indicating the vehicle speed;
A road determination unit that determines the type of road by determining the number of passing lanes according to the lane image extracted by the image analysis unit and the travel distance calculated by the travel distance calculation unit;
A storage unit for storing the type of road determined by the road determination unit;
It is characterized by providing.
[0009]
In order to achieve the above object, a navigation system according to the second aspect of the present invention provides:
Current position acquisition means for acquiring the current position of the vehicle;
Storage means for storing map information;
Imaging means for sequentially capturing road surface images while the vehicle including the lane is running;
Measuring means for measuring the distance between the lanes according to the road surface image taken by the imaging means;
A discriminating means for discriminating the type of the road that is running according to the distance measured by the measuring means;
According to the type determined by the determination means, a road that is running is identified from the map information stored in the storage means, and a correction means for correcting the current position acquired by the current position acquisition means;
Display means for combining and displaying a symbol mark indicating the current position corrected by the correction means on a map image according to the map information stored in the storage means,
The measuring means includes
Lane number measuring means for sequentially identifying lane parts included in the road surface image captured by the imaging means, and measuring the number of lane parts specified within a predetermined time;
Travel distance measuring means for acquiring vehicle speed data indicating a vehicle speed, and measuring a travel distance traveled by the vehicle within a predetermined time according to the acquired vehicle speed data;
Lane interval measuring means for measuring the distance between lanes drawn on the road surface in accordance with the number of lane parts measured by the lane number measuring means and the travel distance measured by the travel distance measuring means. ,
It is characterized by that.
[0010]
In order to achieve the above object, the present invention3Related to the point of viewMap matching methodIs
An imaging step of capturing a landscape image of the vehicle traveling direction including the road surface;
An image analysis step of extracting a lane image drawn on the road surface from a landscape image taken at the imaging step and measured by a predetermined timer;
A travel distance calculating step for calculating a travel distance of the vehicle that traveled between the reference screen and the predetermined screen according to the output of the vehicle speed pulse indicating the vehicle speed;
A road determination step for determining the type of road by determining the number of passing lanes according to the lane image extracted in the image analysis step and the travel distance calculated in the travel distance calculation step;
A storage step of storing the type of road determined in the road determination step in a predetermined storage unit;
It is characterized by providing.
[0011]
In order to achieve the above object, a map matching method according to a fourth aspect of the present invention includes:
A current position acquisition step for acquiring the current position of the vehicle;
An imaging step for sequentially capturing road surface images while the vehicle including the lane is running,
In accordance with the road surface image captured in the imaging step, a measurement step for measuring the distance between lanes;
A determination step of determining the type of road that is running according to the distance measured in the measurement step;
According to the type determined in the determination step, a road that is running is specified from the map information stored in a predetermined storage unit, and a correction step for correcting the current position acquired in the current position acquisition step, Prepared,
The measurement step includes
A lane number measuring step for sequentially identifying the lane portions included in the road surface image captured in the imaging step and measuring the number of lane portions identified within a predetermined time;
A travel distance measurement step of acquiring vehicle speed data indicating a vehicle speed and measuring a travel distance traveled by the vehicle within a predetermined time according to the acquired vehicle speed data;
Lane distance measuring step for measuring the distance between lanes drawn on the running road surface in accordance with the number of lane parts measured in the lane number measuring step and the travel distance measured in the travel distance measuring step And comprising
It is characterized by that.
[0012]
In order to achieve the above object, a recording medium according to the fifth aspect of the present invention provides:
An imaging step for capturing a landscape image in the vehicle traveling direction including the road surface, and an image analysis for extracting a lane image drawn on the road surface from the landscape image captured at the imaging step and measured by a predetermined timer A travel distance calculating step for calculating a travel distance of a vehicle that has traveled between a reference screen and a predetermined screen according to an output of a vehicle speed pulse indicating a vehicle speed, a lane image extracted in the image analysis step, and The number of passing lanes is obtained according to the travel distance calculated in the travel distance calculation step, the road determination step for determining the road type, and the road type determined in the road determination step are stored in a predetermined storage unit. And storing a program for causing the computer to execute the map matching method.
[0013]
In order to achieve the above object, the present invention6Related to the point of viewrecoding mediaIs
A current position acquisition step of acquiring the current position of the host vehicle, an imaging step of sequentially capturing a road surface image of the host vehicle including the lane, and a distance between lanes according to the road surface image captured in the imaging step Stored in a predetermined storage unit according to the determination step, the determination step for determining the type of the road that is running according to the distance measured in the measurement step, and the type determined in the determination step And a correction step of correcting the current position acquired in the current position acquisition step, and the measurement step is performed on the road surface image captured in the imaging step. The lane number measurement step for measuring the number of lane parts specified within a predetermined time and the vehicle speed data indicating the vehicle speed are acquired, and the acquired vehicle speed is sequentially specified. The travel distance measurement step for measuring the travel distance traveled by the vehicle within a predetermined time according to the data, the number of lane parts measured in the lane number measurement step, and the travel distance measurement step A program for causing a computer to execute a map matching method having a lane interval measuring step of measuring a distance of an interval between lanes drawn on a running road surface according to a travel distance is recorded.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
A navigation system according to an embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing an example of a navigation system applied to the embodiment of the present invention. As shown in FIG. 1, the navigation system includes a device main body 1, a monitor 2, and an imaging device 3.
[0017]
The main device 1 includes a flash memory 11, a VRAM 12, a RAM 13, a GPS unit 14, a gyro 15, a CPU 16, a white line monitoring unit 17, and a disk playback unit 18, which are connected via a bus 19. ing.
[0018]
The flash memory 11 includes a flash EEPROM (Electrically Erasable Programmable ROM) or the like, and stores past travel information (movement locus, date and time information, etc.), landmark information set by the user, and the like.
[0019]
A VRAM (Video RAM) 12 is a display-only memory that stores a map image or the like that is a basis of a navigation screen displayed on the monitor 2.
[0020]
A RAM (Random Access Memory) 13 sequentially stores position information acquired by the GPS unit 14, current position information corrected by the CPU 16, and the like. The RAM 13 stores a guide route from the departure place to the destination.
[0021]
A GPS (Global Positioning System) unit 14 tunes to a satellite radio wave transmitted from a plurality of GPS satellites and received by a predetermined GPS antenna, and despreads and demodulates each satellite radio wave to obtain a plurality of satellite reception signals. The GPS unit 14 generates position information including latitude, longitude, altitude, and the like based on the difference in arrival times of the satellite radio waves calculated according to the acquired satellite reception signals.
The GPS unit 14 supplies the generated position information to the CPU 16 at every predetermined timing.
[0022]
The gyro 15 measures the traveling direction of the vehicle and supplies the CPU 16 with angle information indicating the angle formed between the measured traveling direction and the reference direction.
[0023]
A CPU (Central Processing Unit) 16 controls the entire main device 1.
Specifically, the CPU 16 controls the disk reproduction unit 18 according to the position information supplied from the GPS unit 14 to read out target map information and the like from the disk. Further, the current position of the host vehicle is corrected so as to be located on the target road in accordance with the position information supplied from the GPS unit 14 and the determination signal supplied from the white line monitoring unit 17.
[0024]
As shown in FIG. 2, the white line monitoring unit 17 includes an image analysis unit 41, a distance calculation unit 42, and a road determination unit 43.
The image analysis unit 41 analyzes the image data sent from the imaging device 3, identifies a white line image (lane portion) included in the image data, and calculates the number of white lines identified within a certain time.
[0025]
Hereinafter, the manner in which the image analysis unit 41 calculates the number of white lines will be specifically described with reference to FIG. As shown in FIG. 3A, the imaging device 3 is arranged on both sides of the vehicle 61 (own vehicle), and the image analysis unit 41 has image data including an image of the white line 62 captured by the imaging device 3. Assume that they are supplied sequentially.
[0026]
The image analysis unit 41 identifies a white line image (lane portion) as shown in FIG. 3B from the supplied image data. The image analysis unit 41 also determines a state that does not include a white line image as shown in FIG.
Then, the image analysis unit 41 pulses the presence / absence of a white line image in the image data supplied from the imaging device 3 as shown in FIG. The image analysis unit 41 calculates the number of white lines by counting pulses (presence or absence of white lines) within a predetermined time.
[0027]
As described above, when the number of white lines that have passed within a predetermined time is calculated, the image analysis unit 41 generates white line number data indicating the calculated number of white lines and supplies the white line number data to the road determination unit 43.
[0028]
Returning to FIG. 2, the distance calculation unit 42 calculates the distance traveled by the vehicle within a predetermined time by using the vehicle speed pulse and the internal timer. That is, the distance calculation unit 42 calculates a travel distance corresponding to the number of white lines calculated by the image analysis unit 41.
The distance calculation unit 42 generates distance data indicating the calculated travel distance, and supplies the generated distance data to the road determination unit 43.
[0029]
The road determination unit 43 generates a determination signal indicating the type of road that is running according to the white line number data acquired from the image analysis unit 41 and the distance data acquired from the distance calculation unit 42.
[0030]
Specifically, the road determination unit 43 calculates the length of the white line interval according to the acquired white line number data and distance data. Here, since the length of the white line interval on the expressway is 20 m and is stipulated by traffic regulations, the road being driven is either an expressway or a general road from the calculated length of the white line interval. Can be determined.
When the road determination unit 43 generates a determination signal indicating the type of expressway or general road, the road determination unit 43 supplies the generated determination signal to the CPU 16.
[0031]
Returning to FIG. 1, the disc playback unit 18 plays back a disc such as a CD-ROM or DVD (Digital Versatile Disk) on which map information including map images and road information is recorded, and the target map is read from the disc. Read the image. The disc playback unit 18 supplies the read map image or the like to the CPU 16.
[0032]
The monitor 2 includes an LCD (Liquid Crystal Display), a CRT (Cathode Ray Tube), and the like, and is connected to the main device 1 via a predetermined signal line. The monitor 2 displays a navigation screen according to a map image or the like stored in the VRAM 12.
The monitor 2 includes a touch sensor 21 and a remote control light receiving unit 22.
[0033]
When the touch sensor 21 is disposed on the front surface (on the display screen) of the monitor 2 and detects contact of a user's finger or the like, the touch sensor 21 supplies information such as a position on the screen where contact is detected to the CPU 16.
[0034]
The remote control light receiving unit 22 receives a command signal or the like sent by an infrared signal or the like from a remote controller (remote controller) (not shown), and supplies the received command signal or the like to the CPU 16.
[0035]
Two imaging devices 3 are installed in a predetermined location of the vehicle, for example, near the bottom of the left and right doors, and sequentially capture images in a predetermined range including white lines captured from the installation position. The imaging device 3 generates image data of the captured image, and sequentially supplies the generated image data to the white line monitoring unit 17.
[0036]
The operation of the navigation system according to the embodiment of the present invention will be described below with reference to the drawings. FIG. 4 is a flowchart for explaining the navigation process performed by the CPU 16. FIG. 5 is a flowchart for explaining white line monitoring processing performed by the white line monitoring unit 17. FIG. 7 is a flowchart for explaining the map matching process in detail.
[0037]
The navigation process shown in FIG. 4 starts after a destination is input from the user via the touch sensor 21 and a guidance route from the departure point to the destination is selected, for example. Also, the white line monitoring process shown in FIG. 5 starts in parallel when the navigation process starts.
Hereinafter, the navigation process shown in FIG. 4 will be described.
[0038]
First, the CPU 16 acquires the current position of the host vehicle from the GPS unit 14 or the like (step S1). That is, the CPU 16 acquires the vehicle position according to the position information generated by the GPS unit 14.
[0039]
The CPU 16 controls the disc playback unit 18 to read out target map information recorded on the disc (step S2). That is, the CPU 16 reads out a map image or the like within a predetermined range centered on the vehicle position via the disc playback unit 18.
[0040]
The CPU 16 performs map matching processing (step S3). That is, the CPU 16 performs a map matching process for correcting the current position acquired in step S1 to a position on the running road in the map image. Details of the map matching process will be described later.
[0041]
The CPU 16 draws a navigation image on the monitor 2 (step S4). That is, the CPU 16 generates a navigation image by combining the map image acquired in step S2 with the symbol mark indicating the current position corrected by the map matching process described above, and displays the generated navigation image on the monitor 2. .
[0042]
The CPU 16 determines whether or not it has arrived at the destination (step S5). That is, the CPU 16 determines whether or not the vehicle has arrived at a preset destination. If the CPU 16 determines that it has not arrived at the destination, it returns the process to step S1 and repeats the processes of steps S1 to S5 described above. On the other hand, if it is determined that the destination has been reached, the navigation process is terminated.
[0043]
In this way, the map matching process corrects the current position correctly on the road on which the vehicle is traveling, and a map image obtained by combining symbols indicating the corrected vehicle position is displayed on the monitor 2.
[0044]
Next, the white line monitoring process shown in FIG. 5 will be described. This white line monitoring process is sequentially executed in parallel with the navigation process described above.
[0045]
First, the image analysis unit 41 acquires image data sent from the imaging device 3 (step S11). That is, the image analysis unit 41 acquires image data including a white line image (lane portion) captured by the imaging device 3.
[0046]
The image analysis unit 41 identifies a white line image and calculates the number of white lines that have passed within a predetermined time (step S12).
That is, the image analysis unit 41 calculates the number of white lines by pulsing the presence / absence of a white line image in the image data supplied from the imaging device 3 and counting pulses (presence / absence of white line) within a predetermined time.
When the number of white lines is calculated, the image analysis unit 41 generates white line number data indicating the calculated number of white lines and supplies it to the road determination unit 43.
[0047]
On the other hand, the distance calculation unit 42 calculates the distance traveled by the vehicle within a predetermined time according to the vehicle speed pulse or the like (step S13).
That is, the distance calculation unit 42 calculates a travel distance corresponding to the number of white lines calculated by the image analysis unit 41 using the vehicle speed pulse and the internal timer.
The distance calculation unit 42 generates distance data indicating the calculated travel distance, and supplies the generated distance data to the road determination unit 43.
[0048]
The road determination unit 43 calculates the length of the white line interval according to the white line number data and the distance data (step S14).
That is, the road determination unit 43 calculates the length of the white line interval according to the white line number data acquired from the image analysis unit 41 and the distance data acquired from the distance calculation unit 42.
[0049]
The road determination unit 43 determines whether or not the calculated white line interval length is substantially equal to 20 m (step S15). That is, the road determination unit 43 determines whether or not the calculated white line interval length is approximately equal to the white line interval length of 20 m defined on the expressway.
[0050]
When determining that the length of the white line interval is not equal to 20 m, the road determination unit 43 supplies the CPU 16 with a determination signal indicating that the vehicle is traveling on a general road (step S16).
[0051]
On the other hand, when it is determined that the length of the white line interval is approximately equal to 20 m, the road determination unit 43 supplies a determination signal to the CPU 16 that the vehicle is traveling on the highway (step S17).
After supplying the determination signal to the CPU 16, the process is returned to step S11, and the above-described processes of steps S11 to S17 are repeatedly executed.
[0052]
In this way, in the white line monitoring process, it is determined whether the running road is a highway or a general road from the length of the white line interval, and the determination result is sequentially supplied to the CPU 16 as a determination signal.
[0053]
Next, the map matching process shown in FIG. 7 will be described. This map matching process is a process called from step S3 in the navigation process described above.
[0054]
First, the CPU 16 acquires arrangement information such as a highway and a general road corresponding to the vehicle position (step S31). That is, the CPU 16 reads the map information recorded on the disc, and obtains arrangement information such as highways and general roads within a predetermined range centered on the vehicle position according to the road information included in the map information.
[0055]
When acquiring the placement information, the CPU 16 determines whether or not an expressway and a general road are placed in parallel (step S32).
More specifically, the CPU 16 determines whether or not the highway 51 and the general road 52 are arranged in parallel within a predetermined distance, as shown in FIGS. 6 (a) and 6 (b).
In addition, as shown in FIG.6 (c) and FIG.6 (d), although the highway 51 and the general road 52 are not always parallel, CPU16 is the state where mutual distance is very near and parallel. Also, it is determined that they are arranged in parallel.
[0056]
On the other hand, as shown in FIGS. 6 (e), 6 (f), and 6 (g), the CPU 16 is arranged when the general roads 52 are arranged in parallel with each other or there are very few parallel places. It is determined that they are not arranged in parallel.
[0057]
If the CPU 16 determines that they are not arranged in parallel, the process proceeds to step S34. On the other hand, when it is determined that they are arranged in parallel, the determination signal supplied from the white line monitoring unit 17 is referred to (step S33). That is, the CPU 16 refers to the determination signal indicating the type of road, and acquires whether the running road is an expressway or a general road.
[0058]
The CPU 16 corrects the vehicle position so as to be positioned on the corresponding road by the pattern matching method or the like (step S34). At this time, when the determination signal is referred to in step S33, the road on which the vehicle is traveling is specified according to the determination signal, and the vehicle position is correctly corrected so as to be positioned on the road on which the vehicle is traveling.
After completing the map matching process, the CPU 16 returns the process to the navigation process (step S4) shown in FIG.
[0059]
In this way, even when highways and ordinary roads are arranged in parallel, map matching is performed while discriminating the type of road on which the vehicle is traveling, thus improving the matching accuracy. Can do.
As a result, when the symbol indicating the vehicle position is synthesized and displayed on the map image, the vehicle position can be appropriately corrected on the running road.
[0060]
In the above embodiment, the distance between white lines (lanes) is measured according to the captured image data, and it is determined whether the road on which the vehicle is traveling is a highway or a general road. However, the discrimination method for an expressway or the like is arbitrary.
For example, instead of imaging the vicinity of the road surface with the imaging device 3, a landscape image around the vehicle is captured, and the road on which the vehicle is traveling is an expressway from the captured landscape image, or a general road It may be determined whether it exists.
[0061]
More specifically, the main device 1 includes a signal monitoring unit instead of the white line monitoring unit 17. Moreover, the imaging device 3 is arrange | positioned near the windshield in a vehicle, and sequentially images the landscape image above a predetermined angle from the front of the own vehicle.
The signal monitoring unit sequentially acquires image data including a landscape image supplied from the imaging device 3, and determines whether or not the image of the traffic light is included in the image data. When the signal monitoring unit determines that the image of the traffic signal is not included while traveling a predetermined distance or more, the signal monitoring unit supplies a determination signal indicating that the traveling road is an expressway to the CPU 16. When it is determined that an image of the traffic signal is included, a determination signal indicating that the road being traveled is a general road is supplied to the CPU 16.
[0062]
Also in this case, when the highway and the general road are arranged in parallel or the like, the CPU 16 specifies the traveling road according to the referred determination signal so that the own vehicle position is located on the traveling road. Correct correctly.
As a result, when the symbol indicating the vehicle position is synthesized and displayed on the map image, the vehicle position can be appropriately corrected on the running road.
[0063]
It should be noted that the navigation system according to the embodiment of the present invention can be realized using a normal computer system, not a dedicated system. For example, a navigation system that executes the above-described processing can be configured by installing the program from a medium (floppy disk, CD-ROM, or the like) that stores a program for executing any of the above-described programs in a computer. .
[0064]
A method for supplying the program to the computer is arbitrary. For example, you may supply via a communication line, a communication network, a communication system, etc. As an example, the program is posted on a bulletin board (BBS) of a communication network, and is distributed via the network.
Then, by starting this program and executing it in the same manner as other application programs under the control of the OS, the above-described processing can be executed.
[0065]
【The invention's effect】
As described above, according to the present invention, when the vehicle position is combined with the map image and displayed, it can be appropriately corrected on the target road.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an example of a configuration of a navigation system according to an embodiment of the present invention.
FIG. 2 is a block diagram illustrating an example of a configuration of a white line monitoring unit.
FIG. 3A is a schematic diagram for explaining a state in which an imaging device arranged in a vehicle captures a white line, FIG. 3B is a schematic diagram of image data showing an end portion of the white line, and FIG. Is a schematic diagram of image data showing white line intervals, and (d) is a schematic diagram for explaining a state of pulsing the presence or absence of white lines.
FIG. 4 is a flowchart for explaining navigation processing according to the embodiment of the present invention.
FIG. 5 is a flowchart for explaining white line monitoring processing according to the embodiment of the present invention;
FIGS. 6A to 6G are schematic diagrams for explaining an arrangement relationship between a highway and a general road.
FIG. 7 is a flowchart for explaining map matching processing according to the embodiment of the present invention;
[Explanation of symbols]
1. Main unit
2 Monitor
3 Imaging device
11 Flash memory
12 VRAM
13 RAM
14 GPS unit
15 Gyro
16 CPU
17 White line monitoring section
18 Disc playback unit
19 Bus
21 Touch sensor
22 Remote control sensor

Claims (6)

An imaging unit that captures a landscape image of the vehicle traveling direction including the road surface;
An image analysis unit that extracts a lane image drawn on a road surface from a landscape image at a time that is imaged by the imaging unit and measured by a predetermined timer;
A travel distance calculation unit that calculates a travel distance of the vehicle that traveled between the reference screen and the predetermined screen according to the output of the vehicle speed pulse indicating the vehicle speed;
A road determination unit that determines the type of road by determining the number of passing lanes according to the lane image extracted by the image analysis unit and the travel distance calculated by the travel distance calculation unit;
A storage unit for storing the type of road determined by the road determination unit;
A navigation system comprising: Current position acquisition means for acquiring the current position of the vehicle;
Storage means for storing map information;
Imaging means for sequentially capturing road surface images while the vehicle including the lane is running;
Measuring means for measuring the distance between the lanes according to the road surface image taken by the imaging means;
A discriminating means for discriminating the type of the road that is running according to the distance measured by the measuring means;
According to the type determined by the determination means, a road that is running is identified from the map information stored in the storage means, and a correction means for correcting the current position acquired by the current position acquisition means;
Display means for combining and displaying a symbol mark indicating the current position corrected by the correction means on a map image according to the map information stored in the storage means ,
The measuring means includes
Lane number measuring means for sequentially identifying lane parts included in the road surface image captured by the imaging means, and measuring the number of lane parts specified within a predetermined time;
Travel distance measuring means for acquiring vehicle speed data indicating a vehicle speed, and measuring a travel distance traveled by the vehicle within a predetermined time according to the acquired vehicle speed data;
Lane interval measuring means for measuring the distance between lanes drawn on the road surface in accordance with the number of lane parts measured by the lane number measuring means and the travel distance measured by the travel distance measuring means. ,
A navigation system characterized by that. An imaging step of capturing a landscape image of the vehicle traveling direction including the road surface;
An image analysis step of extracting a lane image drawn on the road surface from a landscape image taken at the imaging step and measured at a predetermined timer;
A travel distance calculating step for calculating a travel distance of the vehicle that traveled between the reference screen and the predetermined screen according to the output of the vehicle speed pulse indicating the vehicle speed;
A road determination step for determining the type of road by determining the number of passing lanes according to the lane image extracted in the image analysis step and the travel distance calculated in the travel distance calculation step;
A storage step of storing the type of road determined in the road determination step in a predetermined storage unit;
A map matching method comprising: A current position acquisition step for acquiring the current position of the vehicle;
An imaging step for sequentially capturing road surface images while the vehicle including the lane is running,
In accordance with the road surface image captured in the imaging step, a measurement step for measuring the distance between lanes;
A determination step of determining the type of road that is running according to the distance measured in the measurement step;
In accordance with the determined type at the determining step, identifying the road traveled from the map information stored in a predetermined storage unit, and a correction step of correcting the current position acquired by the current position acquisition step, a Prepared,
The measurement step includes
A lane number measuring step for sequentially identifying the lane parts included in the road surface image captured in the imaging step and measuring the number of lane parts identified within a predetermined time;
A travel distance measurement step of acquiring vehicle speed data indicating a vehicle speed and measuring a travel distance traveled by the host vehicle within a predetermined time according to the acquired vehicle speed data;
Lane distance measuring step for measuring the distance between lanes drawn on the running road surface in accordance with the number of lane parts measured in the lane number measuring step and the travel distance measured in the travel distance measuring step And comprising
A map matching method characterized by that. An imaging step for capturing a landscape image in the vehicle traveling direction including the road surface, and an image analysis for extracting a lane image drawn on the road surface from the landscape image captured at the imaging step and measured by a predetermined timer A travel distance calculating step for calculating a travel distance of a vehicle that has traveled between a reference screen and a predetermined screen according to an output of a vehicle speed pulse indicating a vehicle speed, a lane image extracted in the image analysis step, and The number of passing lanes is obtained according to the travel distance calculated in the travel distance calculation step, the road determination step for determining the road type, and the road type determined in the road determination step are stored in a predetermined storage unit. and storage step, computer-readable recording a program for executing the map matching method on a computer having a recording Body. A current position acquisition step of acquiring the current position of the host vehicle, an imaging step of sequentially capturing a road surface image of the host vehicle including the lane, and a distance between lanes according to the road surface image captured in the imaging step Stored in a predetermined storage unit according to the determination step, the determination step for determining the type of the road that is running according to the distance measured in the measurement step, and the type determined in the determination step And a correction step of correcting the current position acquired in the current position acquisition step, and the measurement step is performed on the road surface image captured in the imaging step. The lane number measurement step for measuring the number of lane parts specified within a predetermined time and the vehicle speed data indicating the vehicle speed are acquired, and the acquired vehicle speed is sequentially specified. The travel distance measurement step for measuring the travel distance traveled by the vehicle within a predetermined time according to the data, the number of lane parts measured in the lane number measurement step, and the travel distance measurement step A computer-readable recording medium having recorded thereon a program for causing a computer to execute a map matching method, comprising: a lane distance measuring step for measuring a distance between lanes drawn on a running road surface according to a travel distance.

Images