JPH0544603B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a traveling position display device for a moving object such as an automobile, which displays the moving state of the moving object, such as the current position, traveling trajectory, and direction of travel.

PRIOR ART In general, when driving a car at night or in unfamiliar areas, in order to provide appropriate guidance so that the driver does not deviate from the planned driving course and get lost, automatic guidance is provided on a preset road map. 2. Description of the Related Art Traveling position display devices for moving objects have been developed that display the vehicle's current position, traveling trajectory, traveling direction, and other moving conditions.

Conventionally, in the case of this type of traveling position display device for a moving object, a distance detector detects the distance traveled by the vehicle according to the vehicle speed, and a direction detector detects the direction in which the vehicle is traveling and the amount of change thereof. Then, the current position of the vehicle, etc. on the travel route is calculated from each of these detected values, and while the results are stored and retained, continuous point information that changes every moment is displayed on the display screen on which a map of the road etc. is displayed in advance. By displaying this information, the driver can confirm the current location.

However, in such a traveling position display device for a moving object, it is unavoidable that position errors occur due to the detection accuracy of the distance detector and direction detector, and as the movement progresses, the errors accumulate and the current The location and travel trajectory up to that point deviate from the road on the map, making it difficult to determine which road the vehicle is currently traveling on.

Purpose The present invention was made in consideration of the above points, and
To provide a moving position display device for a moving body that automatically corrects the current position of the moving body displayed on a map and the travel trajectory up to that point so that it is always on the road.

Configuration An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows the basic configuration of a traveling position display device for a moving object according to the present invention. Distance detector 1 that generates a signal according to the moving distance of
and a direction detector 2 that outputs a signal proportional to the direction or the amount of change in direction depending on the traveling direction of the moving body, which is composed of a rate-type gyroscope that detects the angular velocity in the yaw direction, for example, and the distance detector 2. The moving distance of the moving body is measured by counting the pulse signals from the detector 1, and the moving direction of the moving body is determined from the output of the direction detector 2. 2 per mileage
A signal processing unit (CPU) 3 that calculates the position on the dimensional coordinates and performs centralized control of the entire device, and the position on the two-dimensional coordinates that changes every moment as determined by the signal processing unit 3. A movement trajectory storage device (RAM) 4 that sequentially stores the data of the mobile object and holds it as finite continuous position information corresponding to the current position of the moving body, and map information that has been digitalized pixel by pixel in advance in raster mode. A map information storage medium 5 in which is stored, and the storage medium 5
A storage medium reproducing device 6 reads out necessary map information from the mobile object, displays a map image on the screen according to the read map information, and displays a map image on the screen based on the position data stored in the movement trajectory storage device 4. A display device 7 that updates and displays the current position, the travel trajectory up to that point, the current direction of travel, etc. on the same screen every moment, and gives a display command to the signal processing device 3 and selects and designates a map to be displayed on the display device 7; You can also change the direction of the displayed map and driving trajectory, shift the display position, display enlarged portions of the map and driving path, change the display format settings such as selecting the display scale, search for the map and driving path, etc. as appropriate. Operation device 8 that can be
It is composed of:

With this configuration, the map accessed as appropriate is displayed on the screen of the display device 7, and as the moving object travels, the map is scaled to a preset map scale rate by the signal processing device 3. Accordingly, the current position on the X-Y coordinates (x,
y) is calculated moment by moment, and the calculation results are sequentially sent to the display device 7 and also sent to the movement trajectory storage device 4 to be stored and held, and the stored contents are constantly read out and continuously displayed to the display device 7. As shown in FIG. 2, the display device 7 displays a display mark M1 indicating the current position of the mobile object on the travel schedule map displayed on the screen, and a display mark M1 indicating the current position of the mobile object, and a display mark M1 indicating the current position of the mobile object on the travel schedule map displayed on the screen. A display mark M2 indicating the direction and a travel locus display mark M3 from the starting point to the current position are displayed in a simulated manner following the moving state of the moving object. At that time, as shown in Figure 3, due to cumulative errors, the current position of the mobile object and its travel trajectory up to that point deviate from the road on the map, making it difficult to determine which road it is currently traveling on. I'm getting used to it.

In particular, in the present invention, when such a moving body is used as a traveling position display device, the data value of the position related to the road on the map stored as digital information by the signal processing device 3 and the data value of the traveling trajectory of the mobile body are combined. If the deviation becomes larger than the certain standard, the current position of the moving object displayed on the map and the travel trajectory up to that point will always be changed to the road according to the road data value. I try to take measures to make automatic corrections like the one above.

At that time, as shown in FIG. 3, for example, if the travel trajectory deviates from the road on the map, the road along the travel trajectory, that is, within a predetermined distance range from the current position of the moving object, and the travel trajectory Search for a road on the map that almost coincides with the direction of The respective data of roads A, B, and C obtained by It is determined that road B with a high road B is the road on which the vehicle is currently traveling, and the data is corrected so that the mark M1 of the current position of the moving object and the mark M3 of the traveling trajectory are displayed on the road B. There is.

Specifically, the signal processing device 3 searches for a road on a map along the travel trajectory and extracts the data of the searched road. This is executed by data processing while comparing and collating the relative position and direction of the travel trajectory and the road based on the data of each road.

Note that, as a specific means for determining the similarity, for example, the following means may be employed.

In other words, the value fc that is obtained by integrating the difference between the change in the direction of the road R〓 and the change in the direction of the travel trajectory r〓, which are functions of distance given by the following equation, over the entire ratio interval a to b is When the travel trajectory and the road are slightly shifted back and forth, the more similar they are, the smaller the value becomes, as shown in FIG. 6, and the minimum value is obtained at a point where they almost match.

fc(τ)=∫ ^b _a ｜R〓(τ+l)−r〓(τ)｜dl…
(1) Therefore, for each searched road A, B, C
By determining fc and comparing each value, it becomes possible to determine similarity.

As described above, according to the present invention, when determining the similarity between the travel trajectory of a moving object and each road on a map, it is not necessary to target all roads on the map when executing the program. Since the processing becomes complicated, the preprocessing is to search for roads on the map along the travel trajectory of the moving object, and narrow down the targets of similarity judgment to the searched roads, so that the similarity can be calculated. The burden of judgment processing is reduced, and even if there happens to be a road with a shape similar to the travel trajectory far away from the current location, erroneous corrections will not be made on that road.

In addition, in the present invention, when there are multiple candidate roads with the same degree of similarity, the data correction process at that time is suspended or stopped, and the display of the travel trajectory that has caused the cumulative error is continued. The road search and the determination of the presence or absence of similarity are continuously performed, and when the determination result of the road with the highest similarity is obtained, the data correction process is executed.

That is, in the display state of the driving trajectory as shown in FIG. 7, it is impossible to determine which road the vehicle is traveling on because the similarity to roads D and E is the same. In such a case, as shown in Figure 8, the display of the driving trajectory progresses until the road with the highest similarity can be determined. Data correction processing will be executed to match the road. At this time, depending on the capacity and ability of the signal processing device 3, it is possible to perform data correction processing from a distance, but after an appropriate distance or time has elapsed, data correction is left to the operator's discretion. It is practical to have the process executed as appropriate.

In addition, in the present invention, when data processing for correcting the travel trajectory is on hold or stopped, the performance of the travel condition and direction detector and distance detector are determined based on the current position of the moving object that is constantly advancing without correction. Search for the calculated position error range expected from the above, and then compare and judge the similarity with the road search described above for the searched road, and if partial similarity is recognized. takes measures to correct and display the current position and travel trajectory of the moving object on the display map so that the similarities near the current position and in the past are displayed in the most consistent manner, ignoring intermediate dissimilar parts. That's what I do.

For example, when a moving object passes over a road H that is not on the map as shown in FIG. Either it will fail midway through the search, or even if it is found, the similarity will be poor and the data correction process will be put on hold. After that, the area around the current position of the moving object is searched, and if the absolute direction error of the discovered road is small and the similarity is good within a sufficient distance range, it is determined that it is the correct driving position of the moving object, As a result, the running trajectory on the display is corrected. Note that from the point in time when this state is reached, the normal data correction process described above will continue to be performed. Figure 9b
Middle F indicates a location where the road search failed, and G indicates a road that was searched as a possible road search. Further, FIG. 10a shows a state in which the display of the travel trajectory has progressed, and thereby shows a state in which good similarity of the searched roads has been obtained as shown in FIG. 10b.

FIG. 11 shows an example of processing blocks in the traveling position display device for a moving object according to the present invention.
Here, the road data for comparison that has been separately stored in advance in the map data storage section 9 or the road data for comparison that has been converted and extracted from the display map is stored in the storage section 10, and the stored road data A search is executed by the road search unit 12 according to the data of the travel trajectory in a certain section according to the display scale read from the storage unit 11 that stores the original travel trajectory data before correction based on the following. It's summery. Further, the degree of similarity between the searched road and the travel trajectory is calculated in the calculation unit 13,
After the road with the highest degree of similarity is selected in the road selection unit 14, the correction amount calculation unit 15 calculates the amount of correction so that the travel trajectory will be on the selected road, and the correction processing unit 16 calculates the amount of correction. Accordingly, the rotation and parallel movement of the traveling locus are corrected as appropriate, and the data of the processed traveling locus is stored in the display traveling locus data storage section 17, and then the corrected moving body is displayed on the display section 18. The driving trajectory of the vehicle is now displayed along with the map. In the figure, numeral 19 is a travel distance detection section, 20 is a direction detection section, 21 is a current position calculation section, 22 is a travel locus data storage section, and 23 is a display map storage section.

Effects As described above, in the traveling position display device of a moving object according to the present invention, based on the traveling trajectory data of the moving object stored in the moving trajectory storage device and the data of each road on the map, A means for searching for a candidate road on a map within a predetermined distance range from the current position of a moving object and substantially matching the direction of the traveling trajectory thereof, and comparing data of the searched candidate road with data of the traveling trajectory. A method for determining the degree of similarity between a candidate road and a travel trajectory and selecting a candidate road with the highest degree of similarity, and a means for displaying the current position of a moving object on the selected candidate road. It is equipped with a means for correcting the display position, and automatically corrects the driving trajectory that deviates from the road on the map due to cumulative errors so that it is always displayed on the predetermined road, so that it always has high accuracy. This has the excellent advantage of being able to display the traveling position of a moving object.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the basic configuration of a traveling position display device for a moving body according to the present invention, Fig. 2 is a diagram showing an example of display contents on the display device, and Fig. 3 shows a traveling trajectory that deviates from the road on the map. A diagram showing the state
Figures 4a, b, and c are diagrams showing the search status of roads, Figures 5a, b, and c are diagrams each showing the similarity between searched roads and travel trajectories, and Figures 6a,
b and c are diagrams showing characteristic diagrams of functions expressing similarity, Figures 7 and 8 are diagrams each showing a state in which the travel trajectory deviates from the road on the map, and Figure 9
Figures a and b are diagrams showing the display state of the travel trajectory and the road search state, respectively, when a mobile object travels on a road that is not on the map, and Figures a and b are diagrams showing the state where the travel trajectory has further progressed and the road search state. FIG. 11 is a diagram showing an example of a processing block in the travel position display device for a moving body according to the present invention. 1... Distance detector, 2... Direction detector, 3...
Signal processing device, 4... Movement trajectory storage device, 5...
Map information storage medium, 6...Storage medium playback device, 7
... Display device, 8 ... Operation device, 9 ... Map data storage section, 10 ... Road data storage section for verification, 1
1... Original trajectory data storage section, 12... Road search section, 13... Similarity calculation section, 14... Road selection section, 15... Correction amount calculation section, 16... Correction processing section, 17... Display trajectory data storage section, 18...
Display section, 19... Travel distance detection section, 20... Direction detection section, 21... Current position calculation section, 22... Trajectory data storage section, 23... Display map storage section.

Claims (1)

[Claims] 1 Based on the respective outputs of the distance detector that detects the distance traveled by the moving object and the direction detector that detects the traveling direction, the signal processing device calculates 2 for each unit distance traveled by the moving object.
The current position on the dimensional coordinates is determined, and the data of the current position, which changes every moment as the moving object moves, is stored and retained in the movement trajectory storage device, and the road map is stored in advance from the digital information recording medium in which the road map is recorded as digital information. The image information of the road map is obtained through the playback device, and the road map and the current position of the moving object are displayed overlappingly on the same screen of the display device using the data of the current position and the image information of the road map. A traveling position display device for a moving object that has been moved, based on data of the traveling trajectory of the moving object stored in the moving trajectory recording device and data for each road on the map, calculates a predetermined distance from the current position of the moving object. A means for searching for a candidate road on a map that is within a range and substantially coincident with the direction of the travel trajectory, and comparing data of the searched candidate road with data of the travel trajectory to determine the candidate road and the travel trajectory. means for determining the degree of similarity between the two candidate roads and selecting the candidate road with the highest degree of similarity; and means for correcting the display position of the moving object so that the current position of the mobile object is displayed on the selected candidate road. A traveling position display device for a moving body, characterized by comprising: