JPS6366414A - Vehicle path guide apparatus - Google Patents

Abstract

PURPOSE:To enable effective path guide to be performed by displaying the position or the running locus of a vehicle together with the position measuring accuracy of a position measuring instrument. CONSTITUTION:A global positioning system (GPS) receiver 6 measures a vehicle position at every prescribed time interval by receiving satellite waves from a combined satellite with the good value of delusion of precision (DOP) and inputs the vehicle position to a CPU 7. The CPU 7 obtains the present vehicle position by an integration method based on output signals from a range sensor 15 and a bearing sensor 16 and further multiplies the present vehicle position by a running vector to obtain a new present position (assumed position). The assumed position is corrected by replacing a reference position with the position measured by the GPS receiver 6. The present position and a running locus are displayed in a point and a line, respectively, on a CRT 17 during path guide. The size of a displayed spot, the width of a displayed line and the like are changed in conjunction with a position measuring accuracy. Thus, the more effective path guide can be performed.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a route guidance device for a vehicle.

[Prior Art] Examples of conventional route guidance devices for vehicles include, for example, Japanese Patent Application Laid-Open No. 60-135817M or Japanese Patent Application Laid-open No. 58-22.
There is one as shown in Publication No. 3017N.

This combines a radio position measuring device and an estimated (integral) position measuring device, and when the radio wave reception condition of the radio position measuring device becomes poor, the radio position measuring device is switched to the estimated position measuring device, and The purpose is to perform predetermined route guidance while measuring the position and displaying the current position or travel trajectory of the vehicle on a map on a display device.

However, these conventional route guidance devices for vehicles are configured to display the current position or travel trajectory as dots or lines of a predetermined size, so even when looking at the displayed current position or travel trajectory, It was not possible to know the positioning accuracy of the position measuring device.

The positioning accuracy of the position measuring means has a direct effect on the quality of route guidance, and is something that drivers would like to know.

[Object of the Invention] In view of the above points, the present invention is capable of displaying the position or traveling trajectory of a vehicle together with the positioning accuracy of a position measuring device,
It is an object of the present invention to provide a route guidance device for a vehicle that can effectively provide route guidance.

[Summary of the Invention] In order to achieve the above object, the present invention, as shown in FIG. 2 and
It is equipped with a display means 3 for displaying the current position or the traveling trajectory during route guidance, and a display controller 4 for changing the display method such as the size of the display point or the width of the display line of the means 3 according to the positioning accuracy. The system is configured so that the positioning accuracy can be determined by looking at the current position or travel trajectory.

[Example] Hereinafter, the present invention will be described in detail using the accompanying drawings.

FIG. 2 is a block diagram of a vehicle route guide device according to an embodiment of the present invention, FIG. 3 is an explanatory diagram of a block map, FIG. 4 is a memory map of an external memory, and FIG. 5 is a CR7
FIG. 3 is a front view of the screen.

As shown in FIG.
OM 8, RAM 9, and sensor interface 10
, a video RAM 11 , an operation panel interface 12 , an input operation section 13 , and an external memory 14 are connected to each other.Sensor interface 10
A distance sensor 15 that outputs a pulse signal of a predetermined value every time the vehicle travels a certain distance, and a direction sensor 16 that detects the traveling direction of the vehicle are connected to the vehicle. Video RAM1
1 is connected to CRTI7. A transparent operation panel (touch panel) 18 provided on the front side of the CRTI 7 is connected to the operation panel interface 12 .

The GPS receiver 6 includes an antenna 6A, measures the vehicle position at predetermined time intervals (for example, 5 seconds) by receiving satellite radio waves for combinations of WI stars with good DOP values, and provides the measured positions to the CPU 7. .

The CPU 7 calculates the estimated (integrated) position, corrects the estimated position, and performs route guidance processing for each fraction of the estimated position based on the programs stored in the systems RO to 18.

Here, the estimated position is calculated by inputting the output signals (vehicle speed signal and traveling direction signal) from the distance sensor 15 and the direction sensor 16 via the sensor interface 10, and multiplying the current position (reference position) by the travel vector. This is done by determining a new current position (estimated position).

Further, the estimated position is corrected by replacing the reference position in calculating the estimated position with the position measured by the GPS receiver 6.

An operation panel 18 provided on the front of the CRTI 7 is used to input the departure point and destination. The input operation unit 13 is formed of a so-called keyboard, and various commands can be issued by operating the keyboard.

As shown in Figure 3, it is expressed in XY coordinates.Figure 19
is a block (1-1>, (1-
2)...(3-3), and the external memory 14 is
Various types of information are stored in blocks.

As shown at 1' in FIG. 4, the external memory 14 has various storage areas.

The area start address storage area M1 is the area M2. This is an area for storing the start address of M3... .

The display map data storage area M2 is an area for storing map data to be displayed on the CRT 17. The display method will be explained in detail in FIGS. 8(a), (b), and (C).

The road data storage area M3 is an area for storing the starting point and ending point coordinates of the linearly approximated road segment 9.1 shown in FIG. 3, as well as information necessary for route guidance related to the line segment intersection i. be.

Topography (:ki/river/railway) The data storage area ~14 is an area for storing data regarding rivers and railroads for route guidance.

The point (public facility, etc.) data storage area M5 is an area for storing the location of public facilities, etc. for route guidance.

As shown in FIG. 5, the current position and travel trajectory are displayed on the CRT 17 as a point 2o and a line 21 during guidance. The radius of point 20 is Rmm.

Let the width of the line 21 be dmIll.

FIG. 6 shows the general flow of route guidance processing.

The route guidance process is started by turning on the main switch in step 601.

Step 60.2 shows the routine of the departure point registration process. Here, the departure location will be registered,
Its outline will be explained in FIG.

Step 603 shows a display processing routine at the departure point. Here, an initial display is performed at the start of the run, details of which are shown in FIG. 8(a).

This will be explained in (b) and (C).

When the vehicle starts traveling, as long as the main switch is turned on (step 605), as the current location changes (step GO6), the routine for screen scrolling and updating of table-free map data shown in step 607 is executed. Operate. In this routine, the screen of the CRT 17 is scrolled so that the current position of the vehicle is always at the center of the screen, and the map data is updated as necessary, the details of which will be explained with reference to FIG.

On the other hand, the current position of the vehicle on the map is determined in step 60.
Current residence calculation process using the integral method shown in 8 and 609 (
(estimated position measurement) routine and the interrupt processing of the current position correction processing routine using GPS. The routine for calculating the current position using the integral method is performed by interrupt processing every fixed distance ΔD, and the routine for calculating the current position by GPS is performed by interrupt processing every fixed time ΔT.
This routine will be explained in detail in FIGS. 10 and 11.

As shown in Figure 7, the departure point registration method is as follows: Step 7
It depends on whether or not GPS positioning is possible, which is determined in step 01.

Whether or not GPS positioning is possible is determined by adding 1 to the positioning dimension (for example,
In two-dimensional positioning, determination is made based on 3) whether or not radio waves can be received from GPS satellites.

Step 702 shows departure point registration processing when GPS 8II is possible, and here the coordinates determined by GPS are registered as the departure point. The reason for assuming that positioning is possible regardless of the DOP value as long as there is a sufficient number of satellites is because it is necessary to obtain a registered point even if the positioning accuracy is somewhat poor at the starting point.

Step 703 is a process of recording the departure point when GPS positioning is impossible. Here, after displaying a map on the CRT 17, a suppression area on the map is detected using the operation panel 18, and the point coordinates of the suppression designated point or the center coordinates of the suppression designated area are registered as the starting point. .

As shown in FIG. 8(a), the process of displaying the departure point starts with the map block indexing operation in step 801.

In step 801, the corresponding block B'X shown in FIG. 3 is selected based on the starting point registered in FIG.

Determine BY size.

In step 802, display data corresponding to blocks BX and BY determined from the display map data M2 shown in FIG. 4 and eight blocks surrounding this block (see FIG. 8(b)) is processed. Search the map data and read it into R△~19.

In step 803, as shown in FIG. 8(C), RΔ
In the map area within M9, display dimensions centered on the departure point v
A rectangular area with side lengths x and vy is extracted and set as the CR7 display area.

In step 804, the standard value of the radius R of the display point 20 shown in FIG.
).

In step 805, the map data in the CRT display area shown in FIG. 8(C) is transferred to the video RAM II, and
The RT 17 is caused to perform a predetermined display.

Next, in step 806, the state of the positioning possible flag is detected, and if the positioning possible flag is "0", the process moves to step 807, and if it is 11111, the process moves to step 807.

In step 807, the positioning possible flag is “0”,
Considering that the specified coordinates shown in step 703 in FIG. 7 are displayed, the radius R of the display point 20 is set to the standard value Ro.

On the other hand, in step 808, considering that the positioning possible flag is "1" and the measurement position shown in step 702 in FIG. 7 is displayed, D
It is determined whether OPla is greater than 10. DOP is 10
If it is greater, go to step 809, if it is less than 10, go to step 8
Move to 07.

In step 809, in view of the fact that the DOP value is greater than 10, the radius R of the display point 20 is adjusted to the degree of deterioration of the positioning accuracy in order to display a state in which the positioning accuracy has deteriorated, and R-Ro. (DOP value/10)...
・Let it be ■.

In step 810, a circle of radius R is drawn with the starting point as the center, and the inward direction is filled in.

As shown in FIG. 9, in the screen scrolling and map data update process, in step 901, it is determined whether the current location is within the previously set center block (BX, BY) (see FIG. 8(b)). to be judged.

If it is determined in step 901 that the current location is within the previously set center block, the process moves to step 904 without changing the map data.

On the other hand, if it is determined in step 901 that the current location is out of the previously set center block (BX, BY), the process moves to step 902, where the map block to which the current location belongs is determined as shown in FIG. ) shown in the center block (B
X, BY), and the map data in RAMQ is updated in step 903.

In step 904, the RA updated in step 903 is
In the map area in MQ, a rectangle centered on the current location (X, Y) and having sides of length VX and VY is set as the CR7 display area (see Figure 8 (C)). In step 905, the CRT display The rear map data is transferred to the video RAM 11 to achieve screen scrolling.

As shown in FIG. 10, the estimated position is measured in step 1.
At 001, the previous current location XY is closed and evacuated.

In step 1002, the vehicle direction θ is read, and in step 10
03. Find the estimated position X, Y in 1004, step 10
05, draw a circle with radius Ro centering on the current location X and Y,
Color it.

And finally, in step 1006, the previous current location (X=
, Width d=2R from Yi to the current location (X, Y) found this time
Draw a straight line o.

As shown in FIG. 11, in the GPS position correction process, it is determined in step 1101 whether three or more GPS satellites can be received.

If it is determined in step 1101 that three or more GPS satellites cannot be received, the process moves to step 1102, where the positioning possible flag is set to 0', and then step 1
A regular interrupt is made to 101.

If it is determined in step 1101 that 34 or more GPS satellites can be received, the process moves to step 1103.

In step 1103, the current location (XG, Y
G) and the combination tiiQui2 at that time.
Step 1104
Proceed to.

In step 1104, it is determined whether the current mode is the departure point mode, and if the current mode is the departure point mode, step 11
05 and here, the current location register IC (X,
Y) is rounded up with the positioning H (XG, YQ), and then the process moves to step 1106, where the positioning enable flag is set to "1°", and then a regular interrupt is made to step 1101.

On the other hand, if it is determined in step 1104 that the current mode is not the σ record mode of the departure point, the process moves to step 1107.

In step 1107, it is determined whether the DOP value calculated in step 1103 is 50 or less, and if it is 1- from 50, it is determined that the current position n has deteriorated to the extent that it cannot be used, and the process moves to step 1102, where: Set the positioning flag to “0”
” and then periodically interrupts to step 1101.

If it is determined in step 1107 that DOPA is 50 or less, the process moves to step 110B.

In step 1108, the previous current positions X, Y are changed to
-As! Then, the process moves to step 1109.

In step 1109, the value of the current location register is rewritten with the current location (XG, Ya) measured by GPS, and the process moves to step 1110.

In step 1110, DOPlil! It is determined whether or not is less than 10, and if it is less than 10, the process moves to step 1111, where the radius R of the display point 200 is set as the standard value Ro.

On the other hand, if it is determined in step 1110 that the DOP value is greater than 10, the process moves to step 1112 in order to set the radius of the display point 20 to an appropriate size in accordance with the positioning accuracy.

In step 1112, the display point 200 radius R is set as D O
In accordance with P IIItI, set R=Ro ・(DOP/10) −■.

In step 1113, a circle of radius R is drawn with the current location (X, Y) as the center, and the circle is filled in.

Step 1114r is the previous current position (X').

Width d=2・R from Yl to current current position fi(X, Y)
Draw a straight line o, complete intermediate processing, and step 1101
Scheduled time v1 included.

As shown below, in this example, by the processing shown in FIGS.
=2・RO represents the estimated position display point 20 with radius R
In addition to representing the radius R of the display point 20 by GPS as a circle of o, if the DOP value is 10 or less, Ro, DOPhi
In the case of l 0 to 50, a rat can be expressed as RO・(DOP/10).

Therefore, the driver can display 1! on the CRT 17 screen shown in FIG. By observing the position, the accuracy of the current position determined by GPS can be intuitively known, and the reliability of route guidance can be known.

In the embodiment described above, as shown in FIG.
Although an example has been shown in which only the display radius of the measurement point is changed according to the positioning accuracy, the display radius of the estimated position may be changed according to the positioning accuracy.

That is, in general, the estimated position is determined by the process shown in FIG. 10 using the previously measured current position by GPS as the reference position, and the error ε of the estimated position is calculated as the error εG of the reference position. It can be assumed that the sum of the estimation errors ε■ approximately proportional to the distance is the value εG+ε■. Therefore,
If the radius R at the display point is determined as a value inversely proportional to the error ε of the estimated position, and the line width d of the travel trajectory is determined based on the radius R determined in this way, the estimated position can also be positioned. Accuracy will now be displayed.

Further, in the embodiments described above, the shape of the display point is shown as a circle, but it goes without saying that the shape may be a "corner", for example, outside of domestic politics.

Furthermore, in the embodiment described above, the size of the display point or display line was changed according to the positioning accuracy, but the accuracy was changed to black,
The positioning accuracy may be shown by color change, with 1a semi-accuracy being shown in blue and low accuracy being shown in red.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but can be implemented in other embodiments by making appropriate design changes.

[Effects of the Invention] As described above, in the q-road in-house device according to the present invention, the display method of the position or traveling trajectory is determined by the positioning v1tα of the position measuring means.
Since it can be changed according to the U, route guidance can be performed effectively.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an overview of this invention, FIGS. 2 to 11 show an example of this invention, 2UII is a block diagram of a vehicle route guidance device, and FIG. 3 is an explanation of map blocks. figure,
Fig. 4 is a memory map of the external memory, Fig. 5 is a front view of a display example of a CRT screen, Fig. 6 is a general flow of route guidance, and Fig. 7 is a 70-chi 1? -t,
Figure 8 <a> is a flowchart of mountain area display processing;
Figure (111 is n v of the map block read into A~1)
Figure 2, Figure 8 (C) is an explanatory diagram of the display area, Figure 9 is a flowchart of screen scrolling and map data update processing, Figure 10 is a flowchart of 1i111 position measurement processing, and Figure 11 is the current location by GPS. It is a flowchart of correction processing. 1... Position measurement means 2... Positioning accuracy recognition means 3... Display control hand Q 4... Display means Ro... Standard value R... Radius of display point d... Travel trajectory Patent Attorney Yasuo Miyoshi Figure 9 Figure 7 Figure 8 (a)

Claims (2)

[Claims] (1) a position measuring means for measuring the current position of the vehicle; a positioning accuracy recognition means for recognizing the positioning accuracy of the means; and a display means for displaying the current position or travel trajectory during route guidance;
A vehicular route guidance device comprising: display control means for changing a display method such as the size of a display point or the width of a display line of the means according to positioning accuracy. (2) The vehicle route guidance device according to claim 1, wherein the position measuring means is a GPS position measuring means, and the positioning accuracy is determined by a DOP value.