JPH061196B2 - Driving route display device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a travel route display device for displaying the current position of a moving body such as an automobile on a screen on which a road map is projected in advance.

2. Description of the Related Art Conventionally, as will be described later in detail, for example, when driving a car in a non-guidance area, an appropriate guidance is provided so that the driver does not get out of the planned course and gets lost. The traveling distance corresponding to the vehicle speed is detected by the distance detector and the traveling direction is detected by the direction detector, and the present position which changes momentarily on the XY coordinates of the automobile is sequentially detected from the detected values. A traveling route display device that is obtained by calculation, and the obtained current position is updated and displayed by point information on a screen on which a road map is displayed in advance so that the driver can confirm the current position. Is being developed.

However, in such a travel route display device, it is inevitable that a position error will occur due to factors such as detection accuracy when distance detection and direction detection are performed according to the traveling state of an automobile, etc. Therefore, the error is accumulated and the current position that is updated and displayed gradually deviates from the road on the map, making it impossible to determine which road on the map the vehicle is traveling on. There is.

Then, by taking a matching means with the pattern of the road on the map and the pattern of the traveling locus obtained by storing and holding the data of the current position which is sequentially updated as the vehicle travels, the error from the road It is conceivable to have the current position deviated from be corrected. That is, all the roads are extracted from the road network in the vicinity where the current position is displayed, and the compatibility between the pattern of each road and the pattern of the traveling locus of a car or the like is checked to find the pattern with the highest matching rate. The designated road is regarded as the road currently running, and the display position of the current position is moved to the matched road.

However, by adopting such correction means, when the roads near the current position are complicated and complicated, all the roads are extracted, and the road patterns of the automobiles etc. are extracted for each of the road patterns. It takes a lot of time to perform the processing for matching.

The present invention has been made in consideration of the above points, and the present position of a moving body deviated from the road due to an error by taking a matching means between the pattern of the traveling locus of the moving body and the pattern of the road on the map. In order to correct the vehicle, it is necessary to extract only the minimum necessary roads that are considered to have traveled by the moving body and to perform efficient matching processing so that the current position of the moving body can be corrected easily and accurately. The present invention provides a traveling route display device capable of continuously performing matching processing even when a moving body is traveling on a road not on the map. .

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

FIG. 1 shows a configuration example of a traveling route display device according to the present invention, which is of a photoelectric type, an electromagnetic type or a mechanical contact type which outputs a pulse signal for each unit traveling distance according to the rotation of a tire of an automobile. The number of pulse signals from the distance sensor 1, the number of pulse signals from the distance sensor 1, and the direction sensor 2 including, for example, a gyroscope that detects a change in the angular velocity in the yaw direction and that outputs a signal proportional to the amount of change in the direction of traveling of the vehicle. The mileage of the vehicle is measured, and the change in the traveling direction is calculated according to the output signal of the direction sensor 2, whereby the position on the XY coordinates for each unit mileage of the vehicle is sequentially calculated.
In addition, a signal processing device 3 including a CPU for performing centralized control of the entire system, a program ROM, a control RAM, and the like, and sequentially changing position data on the XY coordinates obtained by the signal processing device 3 are sequentially obtained. Store and
A traveling locus storage device (RAM) 4 that holds finite continuous position information corresponding to the current position of the vehicle, a map information storage medium 5 in which a plurality of map information is stored in advance in file units, and the storage medium 5 A storage medium reproducing device 6 which selectively reads out a necessary map file from the map, a map image is displayed on the screen according to the read map file, and based on the position data stored in the traveling locus storage device 4. A display device 7 for renewing and displaying the current position of the automobile, the traveling locus up to that point, the current traveling direction, etc. on the same screen every moment, and an operation command to the signal processing device 3 and selection of a map to be displayed on the display device 7. Designate and set the starting point of the vehicle on the displayed map, and change the direction of the displayed map and traveling locus, and display it. Location of the shift, is constituted by an operating device 8 which can be done appropriately map and the travel locus of the partially enlarged view, and setting change of a display form, such as selection of a display scale.

With such a configuration, the selectively read map is displayed on the screen of the display device 7, and is preset by the signal processing device 3 according to the traveling of the vehicle from the starting point set on the map. The current position on the XY coordinates is obtained by calculation every moment in accordance with the scale ratio of the map thus calculated, and the calculation result is sequentially sent to the traveling locus storage device 4 to update its stored contents. The stored contents are constantly read and sent to the display device 7. As a result, on the display device 7, as shown in FIG. 2, a display mark M1 indicating the current position of the vehicle on the map displayed on the screen, a display mark M2 indicating the traveling direction of the vehicle at the current position, and a departure mark. A running locus display mark M3 from the point S to the current position is simulated and displayed following the running state of the automobile.

The above configuration and operation are the same as those of the conventional travel route display device described at the beginning.

Therefore, in such a traveling route display device, as shown in FIG. 3, the current position and the traveling locus up to that point gradually deviate greatly from the road on the map as the vehicle travels due to the accumulated error described above. In the end, it becomes impossible to judge where on the map the vehicle is currently traveling.

Specifically, according to the present invention, as shown in FIG. 12, in the signal processing device 3, the road currently being traveled on the map read from the storage medium reproducing device 6 at every constant travel of the moving body. Estimated current position setting means for renewably setting the estimated current position of the moving body on the road above and on the road branched from the road, and the current position and estimated current position of the moving body calculated during traveling for a certain distance. And an estimated current position selecting means for selecting an estimated current position within a preset first distance range, and a current position of the moving body when the estimated current position does not exist within the first distance range. By setting a temporary estimated current position on a road within a preset second distance range around the center, and updating the temporary estimated current position on the same road for each constant traveling distance of the moving body. Iku temporary estimated current position setting means , Estimated current position determination for determining the provisional estimated current position when the distance between the current position of the mobile body and the updated provisional estimated current position is within the first distance range Means for matching the pattern of the road on which the selected estimated current position or the estimated current position determined to be true exists with the pattern of the traveling locus of the moving body read from the traveling locus storage device 4. The current position for correcting the current position so that the current position of the moving body is displayed at a predetermined position according to the pattern matching means and the estimated current position set on the road where the pattern is matched. I am trying to take corrective measures.

The signal processing device 3 has its display control means,
The road map is displayed on the screen of the display device 7 based on the map data of the predetermined area read from the storage medium reproducing device 6, and the current position of the moving body calculated by the current position calculating means is displayed on the road map. As the vehicle travels, it is updated and displayed, and according to the correction data of the current position given by the current position correction means for each fixed distance, the moving object displayed on the road map at that time is displayed. The display will be changed from the current position to the corrected position.

Below, each of the above-mentioned means employed in the signal processing device 3 will be described in detail.

In such a travel route display device, in the present invention, under the control of the signal processing device 3, when the current position of the moving body and the travel locus up to that point deviate from the road on the map,
Match the pattern of each road in the vicinity with the pattern of the moving locus of the moving body, consider the road with the matching pattern as the currently running road, and display the current position of the moving body on the road. The display position of the running track is corrected.

At that time, particularly in the present invention, when matching the pattern of the traveling locus of the moving body and the pattern of the road, the road candidate to be matched with the pattern is selected to the minimum necessary as follows. Then, the load of the matching process is reduced.

First, the estimated current position of the moving body is set on the road on which the vehicle is currently traveling and on all roads branching from the road according to the constant traveling distance of the moving body.

At this time, as shown in FIG. 4 (a), if there is no branch road within a certain distance L from the set point of the previous estimated current position x ', the road is currently running and the moving body is running. Therefore, the estimated current position x is set at a position advanced by the certain distance L. Further, as shown in FIG. 4 (b), if there are branch roads within the certain distance L, the estimated current positions x1, x2, x3 are set to all of the branch roads, respectively. Where l
There is a relationship of 1 + l2 = l1 + l3 = l1 + l4 = L.

The estimated current position is set in the position data of the road in the map displayed on the screen of the display device 7 each time the distance sensor 1 detects that the moving body has traveled a certain distance L. Therefore, it is automatically performed under the control of the signal processing device 3. The estimated current position may be set independently of the travel distance of the moving body, and the estimated current position may be sequentially set every time a predetermined time elapses as the moving body travels. It is also conceivable to change the set interval of the estimated current position according to the traveling condition of the mobile body. Each road is segmented into lines, and position data on the XY coordinates of each line segment is stored in the map information storage medium 5.

Next, check whether the distance between the estimated current position set as described above and the current position of the moving object calculated at that time and displayed off the road is within a predetermined allowable range. A determination is made and an estimated current position within that range is selected, and only roads where the selected estimated current position exists are candidates for matching.

Now, for example, in the relationship of FIG. 5, the estimated current position x (x
1, x2, x3) and the current position P is D (D
1, D2, D3), the estimated current position within the preset first distance range that satisfies the following equation D ≦ αL + M (1) is selected.

Here, M is a preset allowable range, for example, 5
It is set to about 0m. α is a coefficient relating to the position accuracy when the traveling distance of the moving body is used as a parameter, and is set to, for example, about 5%. For L, it is 100
It is set to about m.

At that time, it is possible to select an estimated current position set on a road having a direction within a certain allowable angular difference with respect to the traveling direction of the current position P of the moving body. .

Then, in the relationship of FIG. 5, if the value of M is set to be relatively small, for example, only x2 is selected as the estimated current position satisfying the condition of the equation (1), and the estimated current position x2 exists. The roads to be set are candidate roads to be subjected to the matching process.

Therefore, according to the present invention, even when there are many roads near the current position deviating from the road, a road candidate having a high probability of being matched as a target of the matching process is selected to a necessary minimum. Therefore, the burden of the matching process can be effectively reduced.

Further, in the present invention, when the pattern of the traveling locus of the mobile body and the pattern of the candidate road are matched, the matching processing is performed successively every time the mobile body travels a certain distance and the estimated current position is set. Since the load becomes large, the direction change amount of the traveling locus of the moving body is constantly monitored, and when the integrated value of the direction change amount exceeds a certain value, the change in the shape of the traveling locus has a great feature. At that time, the matching process according to the pattern of the traveling locus of the moving body during the integration period up to then is executed at one time.

That is, as shown in FIG. 6, X of the traveling locus at each point a, b, c, d, ... For each constant traveling distance l of the moving body.
The angle wi formed by the axis (i = 1, 2, 3, ...) Is obtained, and the integrated value W of the direction change amount is sequentially calculated according to the following equation.

When the calculated total amount W of directional changes is equal to or greater than a preset value, traveling from the current position P of the moving body at that time to a start point a (which becomes the previous matching processing point) The locus is extracted as the target of this matching process.

Therefore, if the matching with the road is performed according to the traveling locus of the moving body in which the extracted pattern has a large feature, the number of matching processes is reduced as a whole, and the accuracy of the pattern is high according to the feature of the pattern. It becomes possible to perform efficient matching processing. At this time, as the road pattern to be matched, as shown in FIG. 7, for example, as shown in FIG. 7, the estimated current position x selected according to the current position P of the moving body is set as the head and the previous matching processing point is set. The pattern of the road that cuts the set points of the past estimated current positions x'up to S is cut out.

When cutting out a road pattern for which multiple estimated current positions are set and performing the matching process at once, select each estimated current position that satisfies the relationship of equation (1) as described above. At each point of
Since the distance between the current position of the moving body and the estimated current position set on the road at that time gradually increases as the moving body travels, the moving body travels (1 It is necessary to increase the value of M in the equation).

Further, in the present invention, when matching the extracted traveling locus pattern of the moving body with the pattern of the candidate road cut out as described above, the traveling locus RP pattern as shown in FIG. Is approximated to a polygonal line by equal length line segments, and the pattern of the candidate road KP is also approximated to a polygonal line form by equal length line segments as shown in FIG. 8 (b). Matching is done using the vector sequence of each line segment.

However, if the matching of the traveling locus of such a moving body and the road on the map is performed using the polygonal line approximation under the same condition, it is easy to compare the direction and position of each corresponding line segment. Therefore, the matching process can be accurately and easily performed.

A specific matching process is performed as follows.

First, the position correlation between the running trajectory pattern and the candidate road pattern, which are approximated by polygonal lines by equal length line segments, is obtained. At that time, after rotating the traveling locus pattern in a predetermined manner so as to match the directionality of the road pattern, the distances between the head points of the corresponding line segments of the traveling locus pattern and the road pattern are integrated. It is a correlation of position.

That is, as the first step, the vector sequence approximated to the broken line of the traveling locus is set to {s1, s2, s3, ..., Sn}, and the vector sequence approximated to the broken line of the candidate road is set to {r1, r.
2, r3, ..., rn} (| s1 | = | s2 |
= ... = | sn | = | r1 | = | r2 | = ... = | rn
|), The rotation angle θ of the vector sequence of the traveling locus is obtained according to the following equation.

Here, ω (i) is a weighting function.

As the second step, according to the rotation angle θ,
(4) is used to rotate the vector sequence of the traveling locus.

By performing the rotation processing of the vector sequence of the traveling locus, the direction detection error can be corrected as a result.

As a third step, the correlation value f of the position is obtained according to the following equation in accordance with the vector sequence of the traveling locus and the vector sequence of the road that have been subjected to the rotation processing.

Next, taking into account the distance detection error in obtaining the current position P of the moving body, the head position x of the candidate road is taken into consideration.
With a vector sequence of roads extended by a certain distance + δ (several tens of meters) according to the road pattern, and with a vector sequence of roads shortened by a certain distance -δ at the head position of the candidate road according to the road pattern, as described above. The correlation value f of the position with the vector sequence of the locus is obtained.

Finally, the smallest one of the obtained correlation values f is selected, and when the selected correlation value f is less than or equal to a reference value, it is determined that matching is achieved, and the result is shown in FIG. As shown, the traveling locus RP is translated such that the current position P of the traveling locus is at the head position (for example, the position of x + δ) of the matched road pattern, and then the traveling locus is set to P point. Rotate by the angle θ to the center and fit on the matched road.

By performing such matching processing, the display position of the current position P of the moving body deviating from the road on the map and the display position of the traveling locus up to that position are corrected.

At that time, the roads cut out by dividing each of the positions x + δ and x−δ, which are obtained by adding or subtracting a certain distance δ from the estimated current position x on the candidate road, and using each of the divided positions as the head position. If the correlation value f with each traveling locus pattern is obtained based on the pattern, and if the smallest correlation value f among them is equal to or less than the reference value, it is determined that matching has been achieved, the matching accuracy will be improved. You will be able to raise it.

In addition, when selecting a candidate road for matching according to the estimated current position x set on the road as described above,
As shown in the figure, when the mobile body is traveling on a road not on the map, the current position P of the mobile body calculated at that time and the estimated current position x set on the road are separated. It may happen that the estimated current position x within the first distance range that satisfies the relationship of the above equation (1) does not exist. In that case, the candidate road is not selected and the matching process fails. It will be possible.

Therefore, in the present invention, even when the moving body is traveling on a road that is not on the map, the estimated current position can be optimally set on the road and the matching process can be continuously performed. I am trying.

That is, when the estimated current position x within the first distance range satisfying the relationship of the equation (1) does not exist, the second distance set in advance from the current position of the moving body calculated at that time. If a road exists within a range (for example, a circle with a radius of 100 m), a search is performed. If a road exists, a temporary estimated current position is newly set at the shortest distance position on the road from the current position. And the new estimated current position is sequentially updated on the same road for each constant traveling distance of the moving body, and the distance between the current position of the moving body and the updated temporary estimated current position is The first that satisfies the relationship of the above equation (1)
If it is within the distance range, the new estimated current position at that time is regarded as the true estimated current position, and the above-described matching process is executed based on the newly set estimated current position thereafter. Specifically, while the moving body is not traveling on the road that is not on the map, its running locus is not displayed, and after the estimated current position is newly set on the searched road. The matching process is performed in the same manner as described above according to the traveling locus of the moving body in.

FIG. 13 shows the travel of the mobile body on the map when the mobile body travels off the road on the map to a road not on the map and then returns to the road on the map and travels again. The locus is shown. Here, when the current position is updated to a, b, c, ... As the moving body travels, up to the point c, the estimated current set on the road according to the current position at that time. The distance to the position x ′ is within the first distance range A1 and is selected, but at the point d, the distance to the next estimated current position x ′ is the first distance range A1.
If the estimated current position x ′ becomes larger than that, the setting operation of the temporary estimated current position x ″ with the second distance range A2 is started. , There is no road in the second distance range A2, and the provisional estimated current position x ″ is not set. Then, the traveling of the road which is not on the map of the moving body progresses, and the provisional estimated current position x ″ is updated, and the distance between the provisional estimated current position x ″ and the provisional estimated current position x ″ is within the first distance range A1. Then, the temporary estimated current position x ″ at that time is determined as the true estimated current position x ′.

The determination as to whether or not the road exists within the second distance range from the current position of the moving body is made even if it is always carried out, and the passage of a fixed time or the unit traveling distance of the moving body (for example, 100 m). ) Or the like, and a predetermined timing may be generated, and this may be performed at each timing.

FIG. 11 (a) shows a case where there is one road R within a circle A having a constant radius centered on the current position P of the moving body. In this case, the road R from the current position P of the moving body is shown. A new estimated current position is set at the intersection Q when the perpendicular line is drawn down.

FIG. 11 (b) shows a case where there are two roads R1 and R2 within a circle A having a constant radius centered on the current position P of the moving body. Each intersection Q when a perpendicular is drawn on each road R1 and R2
New estimated current positions are set in 1 and Q2, respectively.

FIG. 11 (c) shows a case where there is a road R in a circle A having a constant radius centered on the current position P of the moving body, but a perpendicular cannot be drawn from the current position P onto the road R. ,
In this case, a new estimated current position is set at the turning point Q3 on the road R closest to the current position P.

When setting the new estimated current position, the radius of the circle may always be constant, but the traveling distance of the moving body after the estimated current position x that satisfies the relationship of the above equation (1) no longer exists. If the radius of the circle is increased in proportion to, for example, when the road is not easily found in the circle, it is possible to deal with the current position P of the moving body being gradually deviated due to the accumulated error.

As described above, in the travel route display device according to the present invention, when the display position deviates from the road on the map due to an error in calculating the current position of the moving body, the moving body up to the current position is displayed. When the current position is corrected by matching the pattern of the traveling locus and the pattern of the road, on the road currently traveling on the map and on all roads branched from the road according to the constant traveling distance of the moving body. The estimated current position of the moving body is set to each and whether or not the distance between the current position of the moving body and the estimated current position calculated when traveling for a certain distance is within a first distance range set in advance. Then, the estimated current position within that range is selected, and the match between the pattern of the road on which the selected estimated current position exists and the pattern of the traveling trajectory of the moving body up to the current position. The moving body is traveling because it is designed to correct the current position of the moving body to a predetermined location according to the estimated current position set on the road where the pattern matching is taken. It is possible to extract only the minimum number of roads that need to be leaked and make it the target of the matching process, so that the efficient matching process can be performed quickly and the current position can be corrected accurately. become.

At that time, in particular, in the present invention, when the estimated current position does not exist within the first distance range, the temporary position is set on the road within the second distance range set in advance around the current position of the moving body. The estimated current position is set, and the temporary estimated current position is updated on the same road for each constant traveling distance of the moving body, and between the current position of the moving body and the updated temporary estimated current position. Since the temporary estimated current position when the distance is within the predetermined distance range is determined as the true estimated current position, when the moving body is traveling on a road not on the map, etc. Also, it has an excellent advantage that the estimated current position can be set while being updated and the above-mentioned matching processing can be continuously performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a travel route display device according to the present invention, FIG. 2 is a view showing an example of a display screen in the embodiment, and FIG. Diagram showing the state of being dislocated, Fig. 4 (a), (b)
Shows a state in which the estimated current position is being set on the road for each fixed traveling distance of the moving body, and FIG. 5 is the current position of the moving body that has deviated from the road and the estimated current position set on the road. FIG. 6 is a diagram showing an example of a state in which the direction of travel of a moving body changes in direction, FIG. 7 is a diagram showing a cutout state of candidate road patterns to be matched, and FIG. ) Is a diagram showing a state in which the traveling trajectory pattern of the moving body is approximated to a polygonal line by equal-length line segments, FIG. 8 (b).
FIG. 10 is a diagram showing a state in which a road pattern is approximated to a polygonal line by equal-length line segments, FIG. 9 is a diagram showing a state in which a current position and a traveling locus of a moving body are aligned on a matched road, and FIG. FIG. 11 is a diagram showing an example of a display screen when the moving body is traveling on a road not on the map, FIG. 11
(a), (b), (c) are diagrams showing a state in which a new estimated current position is set on a road within a fixed circle centered on the current position of the moving body, and FIG. 12 shows the present invention. FIG. 13 is a block diagram showing each means used in the signal processing device for carrying out the invention, and FIG. 13 shows that the moving body deviates from a road on the map to a road not on the map and then returns to the road on the map again. It is a figure which shows the running locus | trajectory of the mobile body on the map at the time of running. 1 ... Distance sensor 2 ... Direction sensor 3 ... Signal processing device
4 ... Running locus storage device 5 ... Map information storage medium 6 ... Storage medium reproducing device 7 ... Display device 8 ... Operating device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoyuki Nishio 1-4-1 Chuo, Wako-shi, Saitama, Honda R & D Co., Ltd. (56) References JP-A-61-196117 (JP, A)

Claims (2)

[Claims] 1. A current position that changes momentarily is calculated by detecting a running distance and a direction of the moving body, and data of the calculated current position is stored and held to obtain a running locus of the moving body. In a travel route display device adapted to update display of the current position of a moving body on a screen on which a road map is projected in advance, for each constant traveling distance of the moving body, on the road currently traveling on the map and its Estimated current position setting means for updating the estimated current position of the moving body on the road branched from the road,
Estimated current position selecting means for selecting an estimated current position that is within a preset first distance range between the current position of the mobile body calculated during traveling for a certain distance and the estimated current position; and the first distance. When the estimated current position does not exist within the range, the temporary estimated current position is set on the road within the preset second distance range centered on the current position of the moving body, and the temporary estimated current position is set. A provisional estimated current position setting means for updating the vehicle on the same road for each constant traveling distance of the moving body,
Estimated current position determination means for determining the temporary estimated current position when the distance between the current position of the moving body and the updated temporary estimated current position is within the first distance range as the true estimated current position A pattern matching means for matching the pattern of the road on which the selected estimated current position or the estimated current position determined to be true exists with the pattern of the traveling locus of the moving body, and the pattern matching means. The present position correction means for correcting the present position so that the present position of the moving body is displayed at a predetermined position according to the estimated present position set on the designated road is characterized. And a travel route display device. 2. The travel route display device according to claim 1, wherein the second distance range is gradually increased according to the travel distance of the mobile body.