JPH0316676B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a device for guiding a vehicle to a destination according to a predetermined route, and a route guidance device for a vehicle that improves the reliability of guidance. Regarding.

[Technical background of the invention and its problems] A vehicle route guidance device is a device that displays a preset expected route for a vehicle on the screen of a display device and guides the vehicle to a destination according to this display. be. What is important in this guidance operation is to accurately detect the current position of the vehicle and to accurately mark and display the detected current position over the planned route displayed on the screen of the display device. be.
When passing through a singular point on the planned route, for example, when passing through the next intersection, the distance relationship to the next intersection is clearly displayed, and the shape of the intersection and the direction in which to turn the intersection are indicated by arrows. This is to indicate the direction in which the vehicle should travel by indicating the direction of the vehicle. The current position of the vehicle is detected based on the vehicle's travel distance detected by the mileage sensor and the vehicle's traveling direction detected by the traveling direction sensor, but the vehicle's traveling distance is determined by the measurement error of the mileage sensor. In addition, the position of the vehicle on the road, such as whether the vehicle is traveling in the left lane or the overtaking lane closer to the center, and the position of the vehicle on the road, such as whether the vehicle is traveling in the left lane or the overtaking lane closer to the center, It varies depending on various factors such as the number of changes, the turning radius when the vehicle turns left or right. Therefore, while the vehicle is traveling on a long route,
When the current position of the vehicle detected based on the travel distance and direction of travel is displayed on the road map on the screen of the display device, it may be displayed at a location different from the location where the vehicle actually exists. be.

In order to solve this problem, the distance traveled for detecting the current position of the vehicle is accumulated between intersections using each intersection as a reference point.
Therefore, it is necessary to detect that the vehicle has passed through an intersection. Conventionally, in order to detect that the vehicle has passed through this intersection, for example, in Japanese Patent Application Laid-Open No. 57-3199, the calculated current position of the vehicle is detected by a device. The point in time when the vehicle exits an area of a predetermined size centering on the pre-registered intersection, which is the next intersection to pass, on the coordinates is determined to be the point in time when the vehicle has passed through the intersection. However, in this determination, the distance from the outer periphery of the area to the center of the intersection definitely occurs as an error, and there is a problem in that it is not possible to accurately detect the passage of the intersection. In particular, in the conventional example, since the size of the area is always substantially constant, it is always constant even when the area for pass determination may be small, for example, and the error increases accordingly. As a result, it is impossible to improve the accuracy of detecting the current position of the own vehicle, and furthermore, it is impossible to improve the reliability of guidance.

[Objective of the Invention] The present invention has been made in view of the above, and its object is to provide route guidance for a vehicle that accurately detects passage of a singular point of a scheduled route leading to a preset destination. The goal is to provide equipment.

[Summary of the Invention] In order to achieve the above object, the present invention, as shown in FIG. , a determination region calculation means E, an inside region determination means F, a singular point passage determination means G, and a current location correction means H, and the direction detection means A detects the direction in which the vehicle is traveling. Distance detection means B
is for detecting the travel distance of the vehicle, the current location calculation means C is a means for inputting the outputs of the direction detection means A and the travel distance detection means B and calculates the current location of the vehicle, and the distance between singular points storage means D is a means for storing distances between a plurality of singular points from a departure point to a destination, and a judgment area calculation means E stores the outputs of the inter-singularity distance storage means D and the singularity passage judgment means G. When it is determined that a certain singular point has been passed based on the information of the singular point passage determination means G, the distance to the next singular point is read from the inter-singular point distance storage means D, and the read distance to the next singular point is The intra-area determining means F inputs the outputs of the current position calculating means C and the determination area calculating means E, and the current position calculating means C
It is a means for determining whether the current position of the vehicle calculated by is within the determination area calculated by the determination area calculation means E, and the singularity passage determination means G is based on the output of the within-area determination means F and the current position calculation means C. The present location correction means H inputs the output of the singularity passage determination means G and corrects the current location of the current location calculation means C. do.

[Embodiments of the Invention] Examples of the invention will be described below with reference to the drawings.

FIG. 2 shows an embodiment of the present invention.

In the figure, 21 is a sensor that detects the heading direction of the vehicle from the earth's magnetic field, 23 is a sensor amplifier that amplifies and shapes the output of the azimuth sensor 21, and 25 is a sensor that generates pulses for calculating mileage according to tire rotation, for example. 27 is a display device that performs various displays; 29 is an operation unit that operates to set a route to a destination; 31 is a control unit that controls the display output on the display device 27 and operates when setting a route to a destination; The route is set by inputting signals from the section 29, and when the vehicle is traveling, the display device 27 compares the detected signals from the direction sensor 21 and the mileage sensor 25 with the set route and displays the traveling direction of the vehicle. It is a microcomputer that displays images.

The display device 27 includes a buffer memory A33, a buffer memory B34, a display control section 35, and a CRT.
It has a display section 37. buffer memory A33
is a buffer memory for temporarily storing intersection shape information, switch part correspondence display information, etc. supplied from the microcomputer 31, and displaying it on the CRT display section 37. The buffer memory B34 is a buffer memory for temporarily storing road map information supplied from the microcomputer 31 and displaying this road map information on the CRT display section 37. The display control section 35 displays on the CRT display section 37 one or both of the intersection shape information stored in the buffer memory A33, the display information corresponding to the switch part, and the road map information stored in the buffer memory B34, in a superimposed manner. It is for control.

The operation unit 29 is provided on the CRT display screen,
Alternatively, it has a transparent operation panel 39 arranged at intervals and a key switch 41 provided near the CRT display section 37.

The transparent operation panel 39 is formed by dividing the screen of the CRT display section 37 into several appropriate blocks vertically and horizontally, and has a plurality of switch parts, which are used by the driver when setting a route to a destination. Switch operations are performed as described later depending on the content on the screen.

The key switch 41 is composed of independent push switches, and has the following functions: "ON", "OFF",
It has four keys: "START" and "CLEAR".

The microcomputer 31 has CRU, ROM,
A central control unit 43 consisting of a RAM, a sensor interface 45 that inputs detection signals from the forward direction sensor 21 and the mileage sensor 25, an input board 47 that inputs signals from the transparent operation panel 39 and the key switch 41, and a central Control unit 43
an output port 49 that outputs signals related to the display processed by the display device 27; a road map storage device 50 that stores road map information; and an output port 49 that outputs signals related to the display processed by It has an intersection data storage device 51 that stores various data regarding intersections that are points. Here, in comparison with the components shown in FIG. Calculation means C, determination area calculation means E, area determination means F, singular point passage determination means G, and current location correction means H correspond to the microcomputer 31, and are further compared with the software of the microcomputer 31 (FIG. 4). Then, the current location calculation means C goes to step 500.
In addition, the determination area calculation means E corresponds to step 230, the within-area determination means F corresponds to step 280, the singular point passage determination means G corresponds to step 300, and the current location correction means H corresponds to step 320.

Next, before explaining the operation of this embodiment, the principle will be briefly explained with reference to FIG.

In Figure 3, a vehicle goes straight through the first intersection 61 and second intersection 87 from the road 77 on the left, turns right at the third intersection 65, and then turns left at the fourth intersection 67, which is split into two. This shows the route you should take when heading towards . Test circles 69, 71, 73, and 75, which are overdetermined regions, are shown at each good intersection, which is a singular point of passage on the planned route. The size of each test circle, that is, the radius of the test circle, is proportional to the distance D between the intersection and the previous intersection, for example 0.1D, depending on the distance between the intersections. It is becoming decided. However, the minimum and maximum values of the radius of this test circle are, for example, 50 m to 50 m, respectively.
Upper and lower limits are set at approximately 100 m or 1 to 1.5 km. In this example, a test circle determined by the distance between intersections is assumed for each intersection, and if a vehicle enters the test circle, it is determined that the vehicle has passed through the intersection. The system determines the time and corrects the coordinates indicating the current position of the vehicle at that time to the center coordinates of the intersection. To explain in more detail, a vehicle is proceeding toward a first intersection 61 on the road 77 on the left, and the test circle 69 for this first intersection 61 is
When it is detected that a vehicle has entered the area, the cumulative distance from the previous intersection which is calculated based on the mileage from the mileage sensor is calculated from the previous intersection which is stored in the intersection information storage means etc. A point 81 whose cumulative distance matches the distance between intersections is detected. When a point 81 with the same distance is detected, the vehicle's current position coordinates are set to the center coordinates 83 of this first intersection, the cumulative distance is cleared to 0, and the vehicle is moved from this center coordinate position to the second intersection. The vehicle proceeds toward the intersection 63 while accumulating the distance again. here,
A dotted line 79 indicates that even if an error occurs, it will be corrected at the intersection. Also, the second intersection 63
When you get close to and enter the test circle 71,
The cumulative distance accumulated from the center coordinates 83 of the first intersection 61 is compared with the inter-intersection distance between this second intersection 63 and the first intersection 61, and a point 85 where both distances match is detected. The current position coordinates of the vehicle are reset to the center coordinate position 87 of the second intersection 63. The same applies when the vehicle turns right or left at an intersection; for example, when turning right at the third intersection 65, it is detected that the vehicle has entered the verification circle 73 at this intersection. Then, within this test circle, a point 89 where the cumulative distance from the second intersection 63 becomes equal to the inter-intersection distance between the third intersection and the second intersection is detected, and at this point, the current position coordinates of the vehicle are determined. is corrected to the center coordinate position 91 of the third intersection 65. In addition, even though the vehicle has entered the respective test circles for each intersection, if a match between the above-mentioned cumulative distance and the distance between intersections is not detected within this test circle, the test circle is It is determined that the intersection has been passed when the vehicle passes through the intersection. In this case, each test circle is not uniformly determined to have a constant size as in the past, but is set according to the distance between intersections, and if the distance between intersections is short, the test circle Since the size of is also becoming smaller, the error is becoming smaller.

Next, the operation of this embodiment will be explained using the flowchart of FIG.

The flowchart shown in Figure 4 shows the process flow (steps) related to route setting work to the destination.
100 to 160) and the processing flow (steps) for guiding and controlling the vehicle to the destination according to the set route.
200 to 500).

First, the processing flow for setting a route to a destination will be explained below using steps 100 to 160 in FIG.

First, when initial settings are made by operating the "ON" switch of the key switch 41, an index image of the road map is displayed on the CRT display section 37. (step
100, 110). Displayed on the screen of the CRT display section 37, a departure area is selected from among the restored road map areas, and the road map of this departure area is displayed on the screen. (Step 120). By pressing the transparent operation panel above the corresponding intersection displayed on the map of the departure area displayed in this way, the shape of the departure intersection registered and the adjacent intersections centered around this departure intersection are displayed. (Step 130).

Next, by pressing the intersection point to be passed from the displayed adjacent intersection, this is detected and this neighboring intersection is registered as the intersection to be passed next (steps 140, 150).

The "START" key is pressed when the route setting work is completed.
This operation is used to guide the vehicle based on this set route, so the next step is
At 160, it is determined whether or not this "START" key has been pressed. In this case, the route setting work has just started and the "START" key has not been pressed yet, so the process returns to step 130 and displays a new adjacent intersection and registers it. Thereafter, the same operations are repeated as shown in steps 130 to 160 until the destination is reached. In this way, the route setting to the destination is completed,
When the "START" key is operated, vehicle guidance control shown in steps 200 onwards is performed.

Next, a description will be given of the vehicle guidance process performed based on the planned route set as described above.

First, when the vehicle approaches the starting intersection where guidance is to be started, which was set in the route setting work, if the "START" key is operated to start guidance,
The coordinates (Xs, Ys) of this starting intersection are set in the buffer memory, and the initial values of the calculations of the calculation processing unit made up of the software of the central control unit 43 are set.
The coordinates Xs and Ys of the departure intersection are set as Xo and Yo.

Once the coordinates of the starting intersection are set in this way, the process proceeds to the next step 205 and then to step 210.
At the same time as starting the subsequent vehicle guidance control, the central control section 43 is interrupted by a distance signal generated from the mileage sensor 25 every predetermined distance ΔD, and performs the interrupt processing shown in step 500. The interrupt processing shown in step 500 integrates the distance signals from the mileage sensor to calculate the cumulative distance, calculates the current position of the vehicle, and calculates the X direction relative to this current position using the formula shown in step 500. Sequentially calculate the coordinates and Y-direction coordinates,
This calculated coordinate position is supplied to a buffer memory and preset. The integration of the travel distance and the calculation of the current position coordinates shown in step 500 are an interrupt operation by the distance signal generated every time the travel distance sensor travels a certain distance ΔD even during the vehicle guidance control operation shown after step 210. This is something that is always done. If this interrupt processing occurs at a step in the middle of a vehicle guidance control operation below step 210, the vehicle guidance control is temporarily interrupted at that step and this interrupt processing step 500 is executed. After that, the vehicle control operation is controlled to return to the original processing step.

In this way, the cumulative travel distance and the calculation of the coordinates of the vehicle's current position are performed by interrupt processing, and at the same time, the guidance control operation of the vehicle is first performed in steps.
Proceeding to step 210, the number of the intersection two places ahead on the set route is read based on the starting intersection that you are currently trying to pass through first, and the section distance D to the next intersection and the next intersection are read from the intersection data storage device 51. The position coordinates Xn, Yn, and the direction of entry and exit from the next intersection are read (steps 210 and 220).

Next, proceed to step 230 to calculate the aforementioned test circle and error zone for the next intersection.
The calculation of this test circle and error zone will be explained using FIG. 5 and FIG. 6, respectively. In FIG. 5, when proceeding from the first intersection P to the second intersection N, the coordinates of the first intersection P are (X ₁ ,
Y ₁ ) and the coordinates (X ₂ , Y ₂ ) of the second intersection N. Let D be the inter-intersection distance between the first intersection P and the second intersection N. Suppose that the vehicle is currently traveling at a point (X, Y) on the road from the first intersection P to the second intersection N.
The square of the distance between Y) and the second intersection N( _X2 , _Y2 ) is (X- _X2 ) ²⁺ (Y- _Y2 ) ² . on the other hand,
As mentioned above, the radius of the test circle 93 is, for example,
Assuming that it is set to 0.1D, the distance relationship when the vehicle enters the verification circle 93 is as follows from the above equation.

(X-X ₂ ) ² + (Y-Y ₂ ) ² = (0.1D) ² Also, FIG. 6 shows the range of the error zone. This error zone 95 is formed outside the area surrounded by four boundary lines 123, 125, 127, and 129, and the first boundary line 123 is centered at the first intersection point P as shown by the dotted line 115. The second boundary line 125 is located at a distance of 1.1D from the second intersection N as indicated by the dotted line 117, and the third and fourth boundary lines 127 and 129 are , are provided so as to form a width of a distance D/2 from the first intersection P and the second intersection N, as shown by dotted lines 119 and 121. Therefore, if the vehicle is now at a certain point (X, Y) within this error zone, the following equation holds true in this case.

(X-X ₁ ) ² + (Y-Y ₁ ) ² = (1.1D) ² (X-X ₂ ) ² + (Y-Y ₂ ) ² = (1.1D) ² Therefore, from this formula, the following It can be derived from Eq.

Y−Y ₂ ≦Y ₂ −Y ₁ /X ₂ −X ₁ (X−X ₂ ) +｜D√X ₂ ² +Y ₂ ² /2X ₂ | Y−Y ₂ ≧Y ₂ −Y ₁ /X ₂ − X ₁ (X−X ₂ ) −|D√X ₂ ² +Y ₂ ² /2X ₂ | Also, when X ₁ =X ₂ , the following equation is obtained.

X≦X ₂ +D/2 X≧X ₂ −D/2 Based on the above formula, the current position of the vehicle (X,
If Y) is known, it is possible to determine whether the vehicle is within the error zone.

In step 230, the verification circle and error zone are calculated in advance based on these formulas, and then,
The CRT display device 37 displays the map of the planned route and the coordinate position of the travel trajectory calculated in step 500 via the buffer memory B34 (step 240). If the next intersection is the destination intersection, a comment "Next is the destination" is displayed on the CRT display section 37. (Steps 250, 260). If the next intersection is not the destination intersection, flag FLG
Set to 0. When this flag FLG is "1", it indicates that the vehicle has entered the test range for the next intersection, and therefore it is set to 0 in advance at step 270. Then, in the next step 280, it is determined whether or not the vehicle has entered the test circle.
Judgment will be made based on the data calculated in 230. When the vehicle enters the test circle, the vehicle is close to the next intersection, so the CRT display unit 37 displays the shape and direction of the next intersection with the previous intersection in front of you. The accumulated distance is then displayed on the top via buffer memory A (step 290), and the cumulative distance is subtracted from the distance D between the previously passed intersection and the next intersection (step 300). As a result, if the inter-intersection distance D is equal to the cumulative distance, the intersection has just been passed, and the coordinates (Xn, Yn) of the intersection are plotted as the current position in the buffer memory. The coordinates (Xn, Yn) of the intersection to be passed are set to the initial value coordinates (Xo, Yn) of the calculation processing unit.
Yo) and reset the distance accumulation up to the next intersection. (step
320, 330). Then, the next intersection is replaced as the intersection to pass through, the guidance intersection is advanced by one, and the process returns to step 210.

In step 300, if the accumulated distance has not reached the distance between intersections, the process proceeds to step 310, where the flag FLG is set to 1,
After this memorizes that the vehicle has once entered the test circle, the process advances to step 280 and checks again to see if it is within the test circle. As a result, if the vehicle is still within the verification circle, steps 290, 300, and
The loop indicated by 310 is repeated, and when the cumulative distance becomes equal to the distance between intersections, the step 320 is repeated.
We will proceed from there.

Also, the result of the check in step 280,
If the vehicle is not within the verification circle, proceed to step 350. Cases in which the vehicle is not within the test circle include cases in which the current position of the vehicle is still far from the next intersection, and cases in which the current position of the vehicle is still far from the next intersection, as explained in the loop of steps 280, 290, 300, and In some cases, the vehicle enters the test circle once, but as a result of the comparison of the stacked distance and the distance between intersections shown in step 300, the two do not match, and the vehicle ends up outside the test circle. In this latter case, i.e. once the vehicle has entered the test circle, the step
If the cumulative distance and the distance between intersections in step 300 are compared and the two do not match and exit the test circle, the flag FLG is set in step 310.
is set to 1, so as a result of checking the flag FLG in step 350, the flag FLG is checked in step 320.
As mentioned above, the coordinates of the intersection to be passed are set as the current position in the buffer memory, and the coordinates (Xn, Yn) of the intersection to be passed are set as the initial value coordinates of the arithmetic processing section, and the guidance intersection is moved one place ahead. The process advances (steps 330, 340) and returns to step 210 to repeat the same operation.
In the former case, that is, if the vehicle is still far before the next intersection and has not yet entered the verification circle, the flag FLG remains 0, so the process advances to step 360 and the vehicle is checked. It is determined whether the current position is within the error zone calculated in step 230. As a result, if the vehicle is within the error zone, a comment "Route Error" is displayed on the CRT display section 37 (step 370). Also, if the vehicle is not within the error zone, make sure that the "CLEAR" key is not pressed and proceed with the above step.
Proceed to step 270 and repeat the same operations as described above. However, if the "CLEAR" key is pressed, there is some kind of mistake and vehicle guidance control cannot be performed, so the step
Return to 100 and start over from the beginning (step 380).

FIG. 7 is a flowchart illustrating the operation of another embodiment of the present invention. In the process shown in the flowchart of FIG. 7, the cumulative distance of the vehicle and the distance between intersections do not match even though the vehicle has entered the verification circle once Even if the vehicle leaves the test circle during this time, the current position coordinates of the vehicle are to be corrected more accurately.

This principle will be explained using FIGS. 8 and 9. Fig. 8 shows a case where a vehicle goes straight through an intersection 97, and the vehicle once enters the test circle 99 as shown by the thick dotted line, but within this test circle, the cumulative distance of the vehicle and the distance between the intersections are different. If the vehicle leaves the test circle 99 from point 101 without matching, the coordinates of the vehicle's current position at the time it exits the test circle are determined by the intersection of the test circle 99 and the road on which the vehicle is traveling. 103 coordinates (Xr, Yr). FIG. 9 is an example of a case where a vehicle turns right at an intersection, and when the vehicle exits from the test circle 107 for the intersection 105 at a point 109, the current position of the vehicle is compared to the test circle 107 and the road where the vehicle is about to turn right. The correction is made using the coordinates of the intersection point 111.

For this purpose, in the flow shown in Figure 7,
The difference is that steps 390, 400, and 410 are provided between step 350 and step 340 instead of proceeding from step 350 to step 320 in the flow shown in FIG. That is, as a result of checking the flag FLG in step 350, if the flag FLG is "1", that is, even though the vehicle has once entered the test area, the cumulative distance of the vehicle does not match the distance between intersections and the test is performed. If you have gone outside the circle, search for the coordinates (Xr, Yr) where the outer edge of the test circle intersects the road extending in the same direction as the vehicle's current direction of travel. Step 390), this intersection coordinate (Xr, Yr) is plotted as the current position, and the intersection coordinate (Xr, Yr) is plotted as the initial value (Xo, Yo) of the calculation of the arithmetic processing section.
Yr) (step 400). after that,
The distance when the vehicle passes the intersection with this test circle is the radius of this test circle from the center of the intersection.
Since the distance corresponds to 0.1D, the cumulative distance is set to 0.1D in step 410.

[Effects of the Invention] As explained above, according to the present invention, by sequentially specifying passing singular points on a route leading to a destination, a scheduled passing route to the destination can be set in advance, and the specified passing singularity can be set in advance. In a device that guides the own vehicle along the planned passage route while sequentially confirming the passing of the singular point, when confirming passage of the passing singular point, the subject vehicle guides the vehicle along the preset passing singular point to be passed next. Passage is determined by detecting that a predetermined passage judgment condition is met by entering a passage judgment area whose size corresponds to the distance from can be detected. By making the passage singular point and passage detection accurate in this way, it is possible to accurately grasp the position of the own vehicle on the planned route, which makes it possible to accurately guide the own vehicle along the planned route. Can be done reliably.

[Brief explanation of the drawing]

Fig. 1 is a diagram corresponding to the claims of this invention, Fig. 2 is a block diagram of a vehicle route guidance device showing one embodiment of this invention, Fig. 3 is a diagram for explaining the principle of this invention, Fig. 4 is a flowchart showing the operation of the vehicle route guidance device of FIG. 2, FIGS. 5 and 6 are diagrams used to explain the flowchart of FIG. 4, and FIG. 7 is a diagram showing another embodiment of the present invention. Flowcharts illustrating the operation of the example, FIGS. 8 and 9 are diagrams for explaining the principle of the operation of FIG. 7. 1...Position detecting means, 3...Singular point indicating means,
5... Judgment area setting storage means, 7... Singularity passage confirmation means.

Claims (1)

[Claims] 1. Direction detection means A, travel distance detection means B,
Current location calculation means C and inter-singularity distance storage means D
, a determination area calculation means E, and an intra-area determination means F.
, singularity passage determining means G, and current location correcting means H
The direction detection means A is for detecting the traveling direction of the vehicle, the travel distance detection means B is for detecting the travel distance of the vehicle, and the current location calculation means C is for the direction detection means A and It is a means for calculating the current location of the vehicle by inputting the output of the traveling distance detection means B, and the inter-singular point distance storage means D is a means for storing the distance between a plurality of singular points from the departure point to the destination. The judgment area calculation means E inputs the outputs of the inter-singularity distance storage means D and the singularity passage judgment means G, and when it is judged that a certain singularity has been passed based on the information of the singularity passage judgment means G, the next Read the distance to the singular point from the inter-singular point distance storage means D,
This is a means for calculating a judgment area according to the read distance to the next singular point, and the within-area judgment means F inputs the outputs of the current position calculation means C and the judgment area calculation means E, and the current position calculation means C
It is a means for determining whether the current position of the vehicle calculated by It is a means for inputting and determining that the singularity has been passed, and a means for correcting the current location H.
A route guidance device for a vehicle, characterized in that it is a means for inputting the output of the singular point passage determination means G and correcting the current location of the current location calculation means C.