JPS5940112A - Correcting method of initial position of navigation system for vehicle - Google Patents

Abstract

PURPOSE:To correct a run track according to a shift in initial set position by repeating the operation of only forward or backward movement if the run track shifts from a road in a map. CONSTITUTION:The run track 100 on a CRT10 is displayed in the order of S1- SN successively from the initial position S and the road 200 is displayed in the order of P1-PN so that a dot corresponding to the S is P and a backward movement point is P-1. If either one occures or every time either of shift keys 32 and 34 is operated, a one-dot correction is made. Namely, an address read of the initial position S(m, n) is made and the data is held in a register in a computer 14. Then, coordinates of the S1 which is the 2nd position behind the initial position S are found. The computer 1 performs arithmetic for finding the P1 and P-1 before and behind the road coordinates P corresponding to the initial position S and corrects the deviation of the run track coordinates S1 easily only by a forward or backward movement command according to the road coordinates P1 or P-1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for correcting the initial position of a vehicle navigation system, and in particular, a method for correcting the initial position of a vehicle navigation system by performing simple operations when a deviation between the road and the travel trajectory stops on the screen. This invention relates to a method for correcting the initial position.

A vehicle navigation system that superimposes the vehicle's travel trajectory on a map screen such as a CRT installed in the vehicle interior and provides directions in order to accurately display the vehicle's current position and guide the correct direction of travel. It is well known that the vehicle can always be driven in the correct direction even in geographically unfamiliar areas, and it is also possible to select the optimal route on the screen and instantly know the distance to the destination, etc. Various extremely useful information can be provided to the driver.

This type of navigation system displays a map as an image on the above-mentioned CRT or by mounting a separately provided translucent map sheet on the CRT screen. The desired driving trajectory is displayed on the map by superimposing the current driving position obtained from the sensor.

An example of this type of display screen is shown in FIG.
The image read out from the desired map memory is displayed on the screen of o, and the driving trajectory 10 indicated by a broken line is superimposed on this image.
0 is displayed. Therefore, the driver can see the driving trajectory 1 on the screen.
You can always check the current position of the vehicle while looking at 00, select the optimal route, or easily know the distance traveled and the distance to the destination.

In normal cases, at the start of driving, the driver sets the initial position of the vehicle on the screen in order to set the initial position @S, and from then on, the vehicle starts traveling according to the direction and vehicle speed obtained from various sensors of the vehicle. A trajectory 100 is calculated and displayed on the screen.

However, the map screen displayed on the CRT 10 is a scaled map and does not indicate all the objects on the road. In many cases, the above cannot be determined. For this reason, it is usually preferable to set the initial position near a road junction or a target shown on a map, but it is not always necessary to select such a set position. Therefore, the initial setting position e on the road 200 may have a large error.

In such a case, since the travel trajectory 100 is displayed on the screen with the initial position S as a reference, the initial deviation will be noticeable on the screen during the travel, as shown in FIG. 1, and the navigation system will not be effective. There was a problem of not being able to work.

In order to correct such an initial deviation, in the conventional method, the entire driving trajectory is corrected and shifted as soon as the deviation is confirmed. Normally M
Correction inputs were made in both the axial and N-axis directions, thereby making the desired deviation correction.

However, in this conventional method, the M-axis and the N-axis are corrected separately to control the position between the travel trajectory 100 and the road 200, so the operation is complicated and there is a problem in that it imposes a great burden on the driver. was there.

The present invention has been made in view of the above-mentioned conventional problems,
The traveling trajectory 10'O itself is only deviated parallel to the road, and its overall trajectory does not need to be corrected at all, and this deviation is caused by the fact that the initial position is mostly in the forward or backward direction on the road 200. Focusing on the fact that this is caused solely by misalignment, we made it possible to automatically move the initial position on the road by simply commanding the forward or reverse direction, and this made it extremely easy to perform correction shifts 1~ It is possible.

In order to achieve the above object, the present invention provides a vehicle navigation system that calculates and displays the driving position of a vehicle on a map screen. is characterized in that the initial setting position is calculated and moved on the corresponding road only by the backward command, and at the same time the travel trajectory is corrected along with the movement of the initial setting position.

Preferred embodiments of the present invention will be described below based on the drawings.

FIG. 2 shows a schematic configuration of a vehicle navigation system to which the present invention is applied, in which the screen display of the CRT 10 installed in a vehicle interior, such as a console box, is controlled by a CRT controller 12. further performs a desired image forming operation on the image f from the microcomputer 14.

In order to display a desired map on the CRT 10, the navigation system is provided with a cassette deck 16, and map information is read from a cassette tape on which predetermined map information is stored. This map information is I1
This map information is input to the computer 14 through the I10 interface 18 and is written and stored in the RAM 22 via another I10 interface 20.

Normally, a commercially available cassette tape can store about 200 pieces of map information, and since this is read into the RAM 22, the driver can read it into the RAM by operating keys on the keyboard 24.
Necessary map information can be read out from M22 as appropriate, and can be displayed as a map on the CRT 10 by the CRT controllers 1 to 12.

On the screen of the CRTI O, which displays the map as described above, the current position of the vehicle and the traveling trajectory are sequentially superimposed and displayed, and the vehicle is equipped with a direction sensor 26 and a vehicle speed sensor 28 in order to determine the current vehicle position. The vehicle direction and speed are transmitted from the I10 interface 18 to the computer 14.
The data is input to the CRT 10 and the desired arithmetic processing is performed.
The current position of the vehicle will be sequentially displayed on the map display.

When the navigation system starts operating, the driver must read out the desired map information to the CRTlo as described above and also perform an initial position setting that shows the vehicle's current position on the map. A cursor movement key 30 for initial position setting is provided, and the cursor can be moved up and down (M
The desired initial position @S is set by sequentially operating in both the horizontal direction (N axis) and the left/right direction (N axis).

FIG. 3A shows an example of a road based on the memory contents of the map information, and the CRTTO screen is divided into 192 dots in the vertical direction (M) and 256 dots in the horizontal direction (N). Dora based on the desired map information! A predetermined map can be drawn on the screen by lighting up -.

Similarly, FIG. 3B shows an example of the memory contents of the travel trajectory, which, like the map information, is displayed as continuous dots on the screen, and these dots can be made into discontinuous lines as necessary to create a desired broken line. Display is possible.

Incidentally, the display of the above-mentioned map and traveling trajectory is processed according to the program in the ROM 31.

FIG. 4 shows an enlarged view of the CRT 10, in which the road 200 is shown with single hatching, and the traveling trajectory 100 is shown with double hatching. The initial position S of the vehicle is displayed in FIG.
z, S2...Displayed like SN. Furthermore, on the screen, the road 200 is shown with a ton 1- which coincides with the initial position S as P, and road dots are shown sequentially as Pl, P2...PN in the forward direction of the vehicle, and in the backward direction of the vehicle. The road dot is shown as P-1.

Furthermore, FIG. 5 shows dots around the initial position S, and it is understood that there are eight dots around the initial position S, and each dot has the coordinates of the initial position S (m
, n), and each coordinate is indicated by adding a +1 or -1 sign in the M and N directions.

Normal travel trajectory writing is done using the direction hinter 26 as before.
Based on the input information from the vehicle speed sensor 28 and the vehicle speed sensor 28, the computer 14 selects the desired travel trajectory driver 1 to CRT1.
A predetermined brightness display is performed on the screen.

A characteristic feature of the present invention is the above-mentioned normal running.

Separately from the line trajectory display, it is possible to easily perform a corrective shift when a deviation occurs between the driving trajectory 100 and the road 200. For this purpose, in the present invention, the keyboard 24 A forward direction shift key 32 and a backward direction shift key 34 are provided for correction, and the desired deviation correction can be performed only by operating one of these shift 1 keys 32 and 34.

FIG. 6 shows a shift chart 70-11 for correcting the overall travel trajectory according to the present invention, and in this embodiment, each time one of the shift keys 32, 34 is operated, a one-dot correction is made sequentially. It is done.

That is, when a correction shift is started, the address of the initial position S (m Sn ), which is the starting point, is read, and the computer 14 holds the initial position MS in its register.

Next, the coordinates of Sl, which is the next dot after the initial position S, are determined.

FIG. 7 shows a subroutine for determining the S1 coordinate, and in this embodiment, eight addresses around the initial position S in the locus memory of FIG. 3B are
The S1 coordinate is read by sequentially determining whether or not there is a signal input "1".

Figure 8 shows this determination order, and seven comparison operations are performed clockwise sequentially from the dot (m-1, n) in the 612-point direction around the initial position S, and in each case When there is memory information corresponding to ``1J'', select this as S.
It is assumed that the 8th and final dot is at coordinate 81 when no corresponding dot is found in these seven comparison operations.

In this way, the coordinates of the next dot 81 after the initial position S can be easily determined. Next, the computer 14 reads the road coordinates for moving (correction shift) the initial position and travel trajectory along the road 200, which will be described later. In order to move to the road 200, set the road coordinates P corresponding to the initial position S.
In order to obtain the coordinates before and after , that is, P+ and P-+, execution of 1-nable-chin is performed. This road position PL,
According to the navigation system of the present invention, by calculating P-1, the travel locus coordinate S1 determined above can be changed to one of the road coordinates P+, P- by only forward or backward commands.
It is possible to easily modify it according to +.

An example of this subroutine (2) is shown in FIGS. 9A to 9C. Similarly to the subroutine (2) shown in FIG. 7, this routine (2) also consists of reading the coordinates before and after the road coordinates P corresponding to the initial position S from the map memory shown in FIG. 3A, and these coordinates are stored in the computer 14. are read into the registers as α and β. In this embodiment, the register read values are two, α and β, because normally there are only two forward and backward dots around the road coordinate P, but there are three or three dots. The fact that there are 4 means that this road coordinate P is a three-way or four-way intersection, and in such a multi-way intersection, the correction shift of the initial position makes it difficult to decide which road to take. This method is targeted at general single roads because the operation becomes complicated and, as mentioned above, correction of the initial position is almost not necessary on such multi-junction roads. As mentioned above, the number of registers is limited to 2-.

In order to sequentially read and act on these two registers, unlike in FIG. 7, the subroutine in FIG. 9 sequentially reads that the dots around the road coordinate P are "1". It performs a discriminative action to flag one and the other, and this is designated as FLP. Therefore, when this subroutine starts, "0" is placed in the register FLP, and each time a "1" dot around the road coordinate P is read, a flag is set.
Recognize that it is a three-way intersection when indicating P.
Finish reading the coordinates of + and P-+.

Also, the order of determination of each coordinate by subroutine ■ is the 10th
Follow the order of the diagram.

In FIG. 9, as mentioned above, at the start of the subroutine, FLP is placed at rOJ, and then.

The coordinates (m-1, n) are determined and this coordinate is
1”, this is stored in register α and at the same time F L
P is set to "1".

Next, according to the order shown in FIG.
-1, n+1) is made, and if this is "1", the reading of register α or register β according to the value of the FLP is performed, and at the same time the reading of register α or register β according to the value of FLP is performed.
is written. As described above, the coordinates around each P are determined in the order shown in FIG. 10, and normally two coordinates P1 or P-1 are stored in either register α or β.

Once P+ and P−+ are obtained in the above manner, the sixth
As shown in the figure, the initial position S and the subsequent travel trajectory are moved, that is, corrected shifts are performed based on the given forward or backward command. As previously mentioned, this shift is performed one dot at a time in the preferred embodiment, a specific example of which is shown in FIG.

When the subroutine (2) starts, the FLP is first compared, and if the FLP is "3", this indicates a three-way intersection, as described above, and no correction is made at this time regardless of the shift operation of the shift keys 32, 34.

Then, when FLP is "2", that is, when it is a normal straight road, the registers α and β are read as coordinates P1 and P-1, respectively, and then these Pl
Then, it is determined whether P-1 is in the forward direction or backward direction with respect to the next coordinate S1 of the initial position S. That is, in FIG. 4, the road coordinates from the initial position S in the forward direction are P+ and the coordinates in the backward direction are P-1, but in the execution of the subroutine H described above, whichever of α and β is forward It is not possible to determine whether the coordinates are
The absolute value of the difference between I and P-1 is compared and the one closer to St is determined to be the forward direction.

After the direction determination is performed, the commands of the shift keys 32, 34 of the keyboard 24 are read for each direction. In this embodiment, the command is first read by reading the forward shift 1-key 32, and if this is not done, then the operation of the backward shift key 34 is read. Then, in response to this shift command, the computer 1/1 calculates and corrects a new travel trajectory from various information such as the initial position S, trajectory coordinate S1, road coordinates P, P+, P-+, and the previous travel trajectory. . That is, when the forward direction shift key 32 is operated, the new traveling trajectory 81 to SN-+1 is basically replaced with the original traveling trajectory S2 to SN, and the initial position @S is the road coordinate. If P1 is in the forward direction of the travel trajectory, the new initial position is set to Pl, and vice versa, the new initial position is set to P-+.

On the other hand, if the reverse direction shift key 34 is operated, the new travel trajectory SI to SN is changed from the previous SN5N-
1 and the new initial position S is replaced with Pl or P-1. In this way, each traveling locus is moved entirely along the one-dot road 200 only by operating one of the shift keys 32, 34.

FIG. 12 shows a state in which the current travel trajectory 1ooa is modified and shifted to a new travel trajectory 100b.
In this state, Pl read into the register α indicates that the vehicle is in the backward direction and the entire traveling trajectory 100 is shifted backward.

As described above, by one operation of the shift keys 32 and 34, the traveling trajectory 100 is moved by one dot on the road 200 and corrected, and if this is repeated until the deviation is corrected,
The initial position can be easily corrected by a single shift key operation without considering the M and N coordinates as in the conventional case.

As described above, according to the present invention, the initial position can be easily corrected through extremely simple operations, and the navigation system can be effectively utilized.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the display screen of a navigation system to which the present invention is applied, Fig. 2 is an overall schematic configuration diagram of the navigation system used in the present invention, and Figs. 3A and 3B are a map and a travel trajectory, respectively. Fig. 4 is an enlarged view of main parts showing the display state of the passage and travel trajectory, Fig. 5 is an explanatory drawing showing the coordinates of display dots, Fig. 6 is a schematic flowchart showing the initial position correction method according to the present invention, FIG. 7 is a flowchart of a subroutine for determining the 81 coordinates in FIG. 6, and FIG. 8 is a determination order of each dot in FIG. 7. Fig. 9 is a subroutine for calculating P+ and P-1 in Fig. 6.
10 is an explanatory diagram showing the judgment order of each dot in FIG. 9, FIG. 11 is a flowchart of the subroutine ■ for moving the locus in FIG. It is an explanatory view showing an example of a modification shift. 10... CRT. 24... Keyboard, 32... Forward direction shift key, 34...
Reverse direction shift key, 100...travel trajectory, 200...road, S...initial position, P...road coordinates. Fig. 3A 111-N (Ot 255) Fig. 3B - Fig. 4 111-N (o~255) [Fig. 5 Fig. 6 Fig. 8 Fig. 111-N Fig. 10 Fig. 12v! J

Claims (1)

[Claims] (1) In a vehicle navigation system that calculates and displays the vehicle's driving position on a map surface, when a discrepancy occurs between the driving trajectory and the road on the map, the initial setting position is determined by only forward or backward commands. 1. A method for correcting an initial position of a vehicle navigation system, characterized in that the initial position of a vehicle navigation system is corrected by moving a vehicle on a corresponding road, and simultaneously correcting a travel trajectory while moving an initial setting position.