JP2665684B2 - Current position display device of moving object - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a moving body current position display device that displays a moving body on a road map projected on a screen in advance while obtaining the current position of the moving body.

Conventional technology Conventionally, for example, when driving a mobile body such as a car in an unguided area, in order to provide appropriate guidance so that the driver does not get off the scheduled course and lose his way, a distance sensor and a direction sensor The current position on the two-dimensional coordinates is obtained by calculation while detecting the traveling distance and the traveling direction of the moving object, respectively, and the current position that changes every moment as the moving object travels is displayed on the screen in advance. 2. Description of the Related Art A current position display device for a moving object has been developed which enables a driver to confirm a current position by sequentially updating and displaying the current position on a road map with point information.

Thus, in such a current position display device of a moving body,
The occurrence of position errors due to factors such as the accuracy of each sensor of the distance sensor and the direction sensor and the calculation accuracy of the significant digits at the time of calculating the current position cannot be denied. There is a problem that the displayed current position gradually deviates from the road on the map, and it becomes impossible to determine on which road on the map the vehicle is traveling.

Also, even if there is no error in the calculated current position of the moving object, if the current position is displayed on the map itself, the current position displayed on the screen will deviate from the road on the map. Become.

Therefore, conventionally, in order to correct the current position deviating from the road on the map, the travel obtained by storing and holding the data of the current position that is sequentially updated according to the road pattern on the map and the travel of the moving object is stored. The matching process with the trajectory pattern is periodically performed so that the traveling trajectory is adjusted on the matched road to correct the current position of the moving body (for example, Japanese Patent Application Laid-Open No.
No. 41817).

At that time, generally, the higher the accuracy of the pattern matching, the larger the amount of calculation required for the matching process. Therefore, when trying to perform high-precision pattern matching to increase the position accuracy of the current position with respect to the road map, an enormous amount of calculation is required. Must be performed in a short time, and the processing load on a computer or the like increases.

Object The present invention has been made in consideration of the above points, and when correcting the current position of a moving object having a position error with respect to a road map, the traveling locus of the moving object by arithmetic processing and the map on the map are used. Without taking the means of matching the pattern with the road,
It is an object of the present invention to provide a current position display device of a moving object, which can easily determine a current position of the moving object on a road map based on a traveling locus of the moving object and a shape of a road on a map.

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

FIG. 1 shows an example of the configuration of a moving body current position display device according to the present invention. For example, a distance sensor 1 that outputs a pulse signal for each unit traveling distance in accordance with the rotation of a tire of the moving body, and a yaw sensor, for example, A direction sensor 2 based on a rate system that detects the angular velocity of the direction change and outputs a signal proportional to the amount of direction change accompanying the traveling of the moving object, and counts the number of pulse signals from the distance sensor 1 to determine the traveling distance of the moving object. The current position on the X-Y coordinates for each fixed traveling distance of the moving object is obtained by sequential calculation by measuring and deviating the traveling direction according to the output signal of the direction sensor 2, and the current position display device of the moving object A signal processing device 3 composed of a microcomputer for performing overall control, and changes every moment as the moving body travels determined by the signal processing device 3. A traveling locus storage device 4 for sequentially storing data of the current position on the Y coordinate and storing it as finite continuous position information of the moving object, and a map information storage for storing a plurality of road map information in advance. A medium 5; a storage medium reproducing device 6 for selectively reading road map information from the storage medium 5; and a predetermined road map based on the read map information. The display device 7 displays the current position of the moving object on the road map along with the traveling locus and the traveling direction of the moving object at the current position, if necessary, and the signal processing device 3. In addition to giving a command, the user is allowed to select and specify a map to be displayed on the display device 7 and to set a starting point of the moving object on the displayed map. To selectively change the direction of the displayed map and travel locus, shift the display position, partially enlarge the map and travel locus, change the display mode settings such as selecting the display scale, etc., as appropriate. And an operation device 8 that can perform the operation.

In such a configuration, the selectively read map is displayed on the screen of the display device 7, and the signal processing device 3 executes the moving object from the starting point set on the map. The current position on the XY coordinates is calculated every moment in accordance with a preset scale of the map, and the calculation result is sequentially sent to the travel locus storage device 4 to update the stored contents. The stored contents are constantly read and sent to the display device 7.

Accordingly, the display device 7 displays, for example, as shown in FIG. 2, a display mark M1 indicating the current position of the moving object on a map displayed on the screen, and indicates a traveling direction of the moving object at the current position. The display mark M2 and the display mark M3 of the traveling locus from the starting point ST to the current position are simulated following the traveling state of the moving object.

The above configuration and operation are the same as those of the conventional moving object current position display device described at the beginning.

Accordingly, in such a moving body current position display device, as shown in FIG. 3, the current position and the running locus gradually deviate from the road on the map as the moving body travels due to the accumulated error described above. Eventually, it becomes impossible to determine which point on the map the vehicle is currently traveling.

The present invention relates to such a current position display device of a moving body, and when correcting a current position having a position error with respect to a road map, the following means by data processing in the signal processing device 3 are provided. Is executed to determine the current position of the moving object on the road map.

As a first means, as shown in FIGS. 4 (a) and 4 (b), the plane on which the traveling locus LP to reach the current position P of the moving object and the plane of the road map RM have the same size. Divide by mesh.

As a second means, as shown in FIG. 5, a line segment in each mesh of a surface of the traveling locus LP divided by the mesh and a surface of the road map RM, and a plurality of line segments prepared in advance as shown in FIG. The degree of similarity to each of the samples (here, for example, sampled into eight types of line segments) is obtained.

As the similarity, for example, using a known pattern matching means, based on the correlation between the positions of the line segments in the samples S1 to S8 and the line segments in the meshes of the plane of the travel locus LP and the plane of the road map RM, for example. It is determined by the matching ratio obtained by the predetermined arithmetic processing.

Alternatively, the similarity is determined as follows.

Now, for example, as shown in FIG.
Are segmented by equally spaced points, and the segmented segment is sequentially shifted for each point.

Then, for example, the line segments (pixels) in the mesh shown in FIG. 6B are sequentially shifted in a stepwise manner corresponding to the shift of the line segments in the sample S2.

At that time, first, a common pixel number is obtained by performing an AND operation on the line segment shifted to the first stage and the original line segment before the shift, and then the line segment shifted after the second stage and its The AND process is sequentially performed on the AND-processed line segment immediately before each shift, and a common pixel number is obtained.

The similarity between the line segment in the sample S2 and the line segment in the mesh shown in FIG. 6 (b) is determined according to the common number of pixels cumulatively obtained by the series of AND processing.

At this time, for example, the similarity between the line segment of the mesh M1 on the surface of the road map RM shown in FIG. 4B and the samples S1 to S8 of each line segment shown in FIG. In terms of values, the similarity is 0.2 for sample S1, 1 for sample S2, 0.4 for sample S3, and similarity for samples S4 to S8. Each becomes 0.

As a third means, as shown in FIGS. 7 (a) and 7 (b), the similarity to each sample S1 to S8 obtained for each mesh is determined on each surface of the travel locus LP and the road map RM. Create hypercolumns that are three-dimensionally represented in columns.

7 (a) and 7 (b), black columns (here, one block in a hyper column is referred to as a column)
Indicates a portion where the similarity becomes 1 of the peak.

In FIG. 7 (b), specific numerical values of the degree of similarity with respect to each of the samples S1 to S8 are exemplarily shown in the hypercolumn portions respectively corresponding to the meshes M1 and M5 on the surface of the road map RM described above. ing.

However, according to the location where the shape of the road on the road map RM matches the traveling locus LP, some of the hyper columns created on the surface of the road map RM shown in FIG.
A portion having the same similarity distribution as the hypercolumn created on the plane of the traveling locus LP shown in FIG. 7A exists.

In the present invention, a distribution having the same degree of distribution as the hypercolumn created on the surface of the traveling locus LP is extracted from the hypercolumns created on the road map RM in two-dimensional directions in both hypercolumns. It seeks out by finding a proper cross-correlation.

As a fourth means, in each column layer of the hyper column created on the surface of the traveling locus LP (a layer composed of each column expressing the similarity of the line segment of each mesh corresponding to the same sample in the hyper column) Each column layer is moved so that columns having similarity peaks overlap in the vertical direction.

Now, for example, if a column having a peak similarity in a hyper column created on the surface of the traveling locus LP is picked up, the result is as shown in FIG.

Here, p1 is a column position at which the similarity in the first column layer is at a peak, p2 is a column position at which the similarity is at a peak in the second column layer, and p3 is a third column position.
Column positions at which the similarity peaks in the column layer. Hereinafter, the same applies.

In the distribution state of the columns having the similarity peaks as shown in FIG. 8, each column layer is appropriately moved in the front-rear direction and the left-right direction so that the peak points p1 to p8 overlap in the vertical direction. .

As a fifth means, each column layer in the hyper column created on the surface of the road map RM is moved correspondingly to the movement of each column layer in the hyper column created on the surface of the travel locus LP. Let it.

FIG. 9 schematically shows a state when each of the column layers L1 to L8 in the hyper column created on the surface of the road map RM is moved.

Due to the movement of each column layer in the hyper column created on the surface of the road map RM, as shown in FIG. 9, the columns having the peak similarities in the respective column layers L1 to L8 vertically overlap. The place is obtained.

In this case, in order for the columns having the similarity peak in the vertical direction to overlap, it is necessary to overlap each column layer in the hypercolumn created on the plane of the traveling locus LP and the hypercolumn created on the plane of the road map RM. The condition is that there is always a column having a similarity peak.

Thus, in the signal processing device 3, as shown in FIG. 9, the head of the traveling locus LP is located at the position of the mesh Mx on the surface of the road map RM corresponding to the position where the column having the similarity peaks in the vertical direction. Current position P of the moving object located at
And the current position P in the mesh Mx
The road map RM is caused to correct the current position P at which a position error has occurred.

The column where the column having the similarity peaks in the hypercolumn created on the surface of the road map RM and in which each of the columns L1 to L8 has been moved is vertically overlapped with each other, specifically, It is determined by subjecting the column layers L1 to L8 to MIN processing.

Further, there may be a plurality of columns having a similarity peak in the column layer of the hyper column created on the plane of the traveling locus LP.

In this case, a column layer having a plurality of columns having similarity peaks is decomposed into a plurality of column layers each having one column having a similarity peak, and the column layer is decomposed into its index. And so on, each column layer is moved so that columns having similarity peaks overlap in the vertical direction.

Now, for simplicity, for example, as shown in FIGS. 10 (a) and 10 (b), a hypercolumn HC1 created on the surface of the traveling locus and a hypercolumn HC1 created on the surface of the road map Consider the case where HC2 is represented two-dimensionally.

In this case, as shown in FIG. 11A, the column layer L4 having the two columns C41 and C42 having the peak similarity in the hypercolumn HC1 is changed to the column layer L41 having the column C41 and the column layer L41 having the column C41. Column layer L4 having column C42
After being decomposed into 2 respectively, the similarity in the column C1 and the column L2 has a peak in the column C1 and the column C2 in which the similarity in the column layer L1 has a peak. Column C3, column layer L41
Are moved so that the column C41 having the peak similarity in the column C42 and the column C42 having the peak similarity in the column layer L42 overlap in the vertical direction.

And each column layer L in the hyper column HC1
Corresponding to the movement of 1, L2, L3, L41, L42, each column layer L1, L2, L3, L41, L42 in the hyper column HC2 is moved as shown in FIG. A location X is obtained where the columns with peak degrees overlap in the vertical direction.

If a situation occurs in which the shape of the traveling locus LP does not match the shape of the road on the road map RM due to an error, the hyper column created on the surface of the road map RM shown in FIG. The traveling locus shown in FIG.
A portion having the same distribution of the similarity as the hyper column created on the LP surface does not exist, and the current position P of the moving object on the road map RM cannot be shifted.

Therefore, when each column layer in the hyper column created on the surface of the road map RM is moved in the same manner as the column movement in each column layer of the hyper column created on the surface of the traveling locus LP, A portion where the similarity in the column layer overlaps in the vertical direction cannot be obtained.

Therefore, in the present invention, in order to eliminate the influence of the mismatch between the shape of the traveling locus LP and the shape of the road on the road map RM, the twelfth computer is processed by the signal processing device 3.
As shown in the figure, means for correcting the similarity of each column three-dimensionally adjacent to the column having the peak similarity in the hypercolumn created on the surface of the road map RM so that the similarity is peaked To take.

That is, even if the width of the column where the similarity in the hyper column created on the surface of the road map RM becomes a peak is set so that the shape of the traveling locus LP and the shape of the road on the road map RM are slightly different, In the width of the hyper column shown in FIG. 12, the traveling locus shown in FIG.
There is a portion having the same distribution of the similarity as the hyper column created on the LP surface.

It should be noted that by performing a process of assigning a width to a column having a peak similarity in the hyper column created on the surface of the road map RM, FIGS.
As shown in (1), when the surface of the traveling locus LP and the surface of the road map RM are respectively divided by meshes, the influence of the irregularity of division by each mesh on both surfaces can be eliminated.

Further, in the present invention, instead of assigning a width to a column having a similarity peak in a hyper column created on the surface of the road map RM, a computer processing in the signal processing device 3 causes a column having a similarity peak. A means is provided for correcting the similarity between the three-dimensionally adjacent columns so as to increase the similarity in accordance with a predetermined algorithm.

As an algorithm, for example, the similarity of a column three-dimensionally adjacent to a column having a similarity peak is 0.
If it is 5, the similarity of the adjacent column is increased to 0.8. If the similarity of the adjacent column is 0.7, it is set to 0.9.
Raise to If the similarity of the adjacent column is 0.8 or more, the similarity is raised to 1.

And in this case, as described above, when each column layer in the corrected hyper column is moved correspondingly to the column movement in each column layer of the hyper column created on the plane of the traveling locus, The position of the mesh on the surface of the road map where the columns having the similarity equal to or more than a certain value (for example, 0.8 or more) overlap in the vertical direction is defined as the current position of the moving object on the road map.

In this case, when there are a plurality of meshes on the surface of the road map in which columns having similarities of a certain degree or more overlap vertically, the position of the mesh in which the column having the highest similarity overlaps on the road map. Is the current position of the moving object at.

As described above, in the current position display apparatus for a moving object according to the present invention, when the current position having a position error with respect to the road map is corrected, basically, the data of the current position is sequentially stored in the memory. Means for dividing the surface of the traveling trajectory of the moving body obtained by holding the surface and the surface of the road map by meshes of the same size, respectively, and the respective of the traveling trajectory surface and the road map surface divided by the mesh Means for respectively calculating the similarity between the line segment in the mesh and the sample of a plurality of line segments prepared in advance, and the similarity for each sample obtained for each mesh on each surface in the traveling locus and the road map. Means for creating hypercolumns that are three-dimensionally represented in a column shape, and the similarity of each column layer of the hypercolumns created on the surface of the running trajectory peaks Means for moving each column layer in the hyper column created on the surface of the road map in accordance with moving each column layer so that the column to be overlapped in the vertical direction, and taking each column The position of the mesh on the surface of the road map where the column where the similarity peaks due to the movement of the layer overlaps in the vertical direction is the current position of the moving object on the road map. The matching of each pattern between the body trajectory and the road on the map is performed by an arithmetic processing requiring a huge amount of calculation, and the current position is corrected by matching the trajectory on the matched road. There is an excellent advantage that the current position of the moving object on the road map can be easily and directly obtained by a simple process without causing the processing to be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a moving body current position display device according to the present invention, FIG. 2 is a diagram showing an example of a display screen in the embodiment, and FIG. FIGS. 4 (a) and 4 (b) are views showing a state where the screen is displayed off the road, and FIGS. 4 (a) and 4 (b) show a state where the plane of the traveling locus LP and the plane of the road map RM are each divided by meshes of the same size. FIG. 5 is a diagram showing each sample of eight types of line segments, and FIG. 6 (a) shows a state in which a line segment in a sample is formed into a point sequence and the line segment of the sample is shifted by one point. FIG. 6 (b) is a diagram showing a state where the line segment in the mesh is shifted correspondingly to the shift of the sample line segment, and FIGS. 7 (a) and 7 (b) are running trajectories and road maps. Fig. 8 shows the hyper column created on each surface of the vehicle. FIG. 9 is a view showing a distribution state of a column having a peak similarity in a hypercolumn created on the surface of a trace, and FIG. 9 shows how each column layer in the hypercolumn created on the road map surface is moved. FIGS. 10 (a) and 10 (b) schematically show the state when the vehicle is turned on, and are created on the surface of the hyper column and the road map created on the surface of the two-dimensionally represented traveling locus. FIG. 11 (a) is a diagram showing a hyper column, and FIG. 11 (a) shows a column in a hyper column created on a plane of a traveling trajectory expressed two-dimensionally so that columns having similarity peaks vertically overlap. FIG. 11 (b) shows a state where each column layer in the hyper column created on the two-dimensionally represented road map surface is formed on the traveling locus surface. Each FIG. 12 is a diagram showing a hyper column created on the surface of a road map when a column having similarity is peaked, and FIG. 12 shows a state where the column is moved in accordance with the movement of the memory layer. . DESCRIPTION OF SYMBOLS 1 ... Distance sensor, 2 ... Direction sensor, 3 ... Signal processing device, 4 ... Traveling locus storage device, 5 ... Map information storage medium, 6 ... Storage medium reproduction device, 7 ... Display device, 8 ......
Operating device, LP: running trajectory, P: current position, RM: road map

Claims (3)

(57) [Claims] 1. While detecting a traveling distance and a traveling direction of a moving body, a current position on a two-dimensional coordinate, which changes with the traveling of the moving body, is sequentially obtained in accordance with the respective detection results. The present position of a moving object in which a position error has occurred with respect to a road map in a moving body current position display device for reading the map data from the device and updating the current position on a screen on which a predetermined road map is displayed Means for dividing the surface of the traveling trajectory of the moving object and the surface of the road map obtained by sequentially storing and holding the data of the current position in the memory by the mesh of the same size, and the mesh The degree of similarity between the line segment in each mesh of the travel locus surface divided by the road map surface and the road map surface and a plurality of line segment samples prepared in advance Means for creating a hyper-column in which the similarity to each sample obtained for each mesh is three-dimensionally expressed in a column on each surface of the travel locus and the road map; and Hypercolumns created on the surface were created on the surface of the road map in accordance with the movement of each column layer so that the columns with similarity peaks in each column layer vertically overlapped Means for moving each column layer in the hyper column, and the position of the mesh on the road map surface where the column where the similarity peaks due to the movement of each column layer vertically overlaps with the moving object on the road map. A current position display device for a moving object, wherein 2. A means for correcting so that a similarity of each column three-dimensionally adjacent to a column having a peak similarity in a hyper column created on a road map surface has a peak. 2. The current position display device for a moving object according to claim 1, wherein each column layer in the hyper column whose column similarity is corrected is moved. 3. While detecting the traveling distance and traveling direction of the moving object, the current position on the two-dimensional coordinates, which changes with the traveling of the moving object, is sequentially obtained according to the respective detection results. The present position of a moving object in which a position error has occurred with respect to a road map in a moving body current position display device for reading the map data from the device and updating the current position on a screen on which a predetermined road map is displayed Means for dividing the surface of the traveling trajectory of the moving object and the surface of the road map obtained by sequentially storing and holding the data of the current position in the memory by the mesh of the same size, and the mesh The degree of similarity between the line segment in each mesh of the travel locus surface divided by the road map surface and the road map surface and a plurality of line segment samples prepared in advance Means for creating a hyper-column in which the similarity to each sample obtained for each mesh is three-dimensionally expressed in a columnar form on each surface of the traveling locus and the road map, and The similarity of each column three-dimensionally adjacent to the column where the similarity in the hyper column created on the surface is the peak,
A means for correcting so as to increase according to a predetermined algorithm, and moving each column layer so that the column having a similarity peak in each column layer of the hyper column created on the plane of the traveling locus vertically overlaps. Means for moving each column layer in the hypercolumn that has been created on the road map surface and that has been modified, so that the degree of similarity becomes equal to or greater than a certain value due to the movement of each column layer. A current position display device for a moving object, wherein a position of a mesh on a road map surface on which a column vertically overlaps is set as a current position of the moving object on the road map.