JPS5830616A - Running guidance device for vehicle - Google Patents

Abstract

PURPOSE:To display the position of the vehicle accurately by compensating the data of the vehicle position to the data of the position of the starting point when the vehicle returns to the starting point and the direct distance from the starting position obtained by the computation is less than a specified distance. CONSTITUTION:Assume that the vehicle runs from the starting position S to the destination G. During this time, the running of the vehicle is guided by a map display, and the vehicle reaches the destination G and returns to the starting point S again. The display of the arrived position S' is deviated from the display of the starting point S on the map display. When the deviation between the points S and S' is within specified distance, the presence position data of the the running guidance device is forcibly moved to the data of the starting point, thereby performing the compensation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a device that calculates and displays the current position of a vehicle based on the traveling direction and distance traveled of the vehicle, and the present invention provides a device that calculates and displays the current position of a vehicle based on the traveling direction and travel distance of the vehicle. ◎Recently, when driving to a predetermined destination, the vehicle is positioned in relation to the destination to make it easier for the driver to reach the destination. This kind of device is called a vehicle travel guidance device.For example, in the 1st FIJ, an example of which is shown in FIG. is a direction sensor that detects geomagnetism and outputs a geomagnetism detection signal and a reference signal that serves as a reference for geomagnetism detection, and snow is a direction sensor! The phase detector detects the phase difference between the geomagnetism detection signal from the ground and the reference signal, and this detected phase becomes a signal representing the traveling direction # of the vehicle with respect to the reference direction. 3 is a distance sensor that detects the distance traveled by the vehicle, and outputs a pulse every time the vehicle travels a certain distance.@4 is a distance sensor that counts the pulses from the distance sensor 3 and calculates the distance traveled per unit cj.
The distance B for outputting pulses every s is the current position of the vehicle calculated based on the vehicle's traveling direction 0 and the unit travel distance @ds, and further determined in advance based on this current position data. Straight line distance to destination and direction # of destination. 6 is a calculation device that calculates and outputs the departure point S ("1 * 3' s ) h of nine vehicles, which is checked on the map.
This is a keyboard for inputting data (for example, coordinate data) of the destination Gtxo, yci). The arithmetic device i calculates the current position P(x,y) of the excavating vehicle by the following equation.

The straight line distance from the current position P to the destination q and the direction of the destination # are expressed by a five-dimensional equation and are determined by six calculations.

1 is the output from the arithmetic device from the current position P to the destination Gt
The straight line distance at and the direction θ of the destination q. A bar graph 78 using a fluorescent display tube is used to display 111 distance, and as the vehicle approaches destination q, the bar graph 8 is turned off from the bottom. to display the distance to the destination. Further, around the bar graph s, a plurality of display arrows 9 pointing in the direction of the destination G from the current position P are provided, and any one of the display arrows 9 indicating the destination is fully lit.

On the other hand, a memory 10 is connected to the performance device 5, and this memory VXO< stores in advance the value of a predetermined declination α of the earth's magnetic field, which varies depending on the region where the vehicle is traveling or the latitude. .

Now, in the above device, in the arithmetic device S.

From the above formula (1), the current position P (x+
y) has been calculated), and when the vehicle enters a predetermined driving area or crosses a latitude of 9, the nine predetermined declination angle α corresponding to the area or latitude of 7° stored in the memory lO is calculated. The linear distance from the current position P to the destination Gt is calculated using the equation (2) based on the current position data obtained using the equation (3). and the angle when the destination at is visible from the current position P -0
is calculated.

According to such a travel guidance device, the direction sensor detects the direction of travel of the vehicle and corrects it according to the latitude of the region in which the vehicle is traveling. It is possible to always obtain correct calculated values for the straight line distance to the destination and the direction of the destination.
> Accumulated errors are also significantly reduced, making it possible to perform highly accurate driving guidance, but since the acquisition of travel distance data during direction data is done by telephone at regular intervals, there is a delay between data acquisition and the next acquisition. Distance mileage in the direction between ica
The error naturally accumulated as the distance traveled (%flC)
, or near the clove reinforcing steel building on the railway bridge.
If you pass through a place where the magnetic field is disturbed, the direction sensor will not be able to accurately detect the direction, which may cause an error in the travel distance. Even if there are many slopes, such as a road with many slopes, an error may occur between the actual distance traveled and the calculated distance traveled. As a result, if a map display 11, such as the one shown in #I snow map, is used for the display device of the vehicle traveling alligator road device, it is possible that the vehicle departs from the departure point S and actually returns to the same departure point S. However, on the display, the vehicle mark will be displayed at a point S' different from the initial departure point 8 due to the error in the mileage due to the above-mentioned calculation, but this is visually unnatural. Therefore, even if you start traveling again after that, it will be necessary to start from that point S'. There is a problem that the data differs from the data at the departure point 8, and the subsequent operator display of the vehicle position is inaccurate.

The present invention has been made in view of the above points, and includes a device 1 that calculates and displays the current location based on the traveling direction and travel distance of the vehicle. When the vehicle arrives at the starting point, the vehicle position data will be corrected to the starting point position data if the calculated straight line distance from the starting point is less than a predetermined distance. This is what I did.

The present invention will be explained below with reference to Drawing Ki II. Figure 1 shows an embodiment of the electric circuit of the travel guidance device according to the present invention. In Figure 1, the same reference numerals as in Figure 1 indicate the same components. There is 0 this lol example! , #i A map display as shown in FIG. 3 is used as the display, and the position of the departure point 8 on the map display is set as the origin of the coordinates.

In the figure, 1 is the setting device that sets the position data correction area, and 13 is the correction area K set according to this setting @111C.
It compares the reference voltage v 驳 to it@m with the voltage vL outputted from the calculation path S to the starting point S and the current position Pt, and calculates vl) vt nod l H(H11
1k) Output level signal s Vl < V4 O
Comparison 11 that outputs a low level signal
st+ is an ignition switch 7 detector that outputs an H level signal when it detects that the ignition switch is turned off; II is an AND circuit that takes the logical product of the output of the comparison 613 and the output of the ignition switch 7 detector 1s. It is.

Now, from departure point 8 (for example, home garage) to destination q
The nine vehicles are guided by the map display, arrive at the destination (1), return to the starting point S (home garage), and return to the starting point S (home garage). At this time, the display on the map display is as described above. For this reason, as in the third ryJ, the departure point 8 and the arrival point 8' at the fourth point 9 are shifted.The operation of the above circuit according to the present invention will now be explained.

The linear distance t between the departure point 8 and the arrival point S' when the vehicle returns to the departure point S (point S' on the display lo) is calculated by the calculation device BK from the following equation, and the distance phase roar voltage vt will be released as.

tw x −X @ 7− Y a ...
(4) On the other hand, the reference voltage vl of the setter 120 is indicated by a broken line on the display 1 and the straight-line distance BK@m from any point on the great circle. In the comparator 11, the voltages Vl and vt are compared, and V, >
If Vt, comparator l! An H level signal is output from. At this time, if the ignition switch is already turned off, the ignition switch is off! 3, an H level signal is output, so the AND condition of the AND circuit 13 is satisfied, and the current position data, that is, the coordinates (x*y) in the arithmetic unit S, is corrected to the data (is, y,) of the departure point 8. Ru. The result is 9 vehicles shown at arrival point 8' on the mourning display shown in Figure 2! - Ku is forcibly moved to departure point 8. That is, when the vehicle returns to the actual starting point 8 (the vehicle mark is displayed at point S' on the display)
If the deviation t between points 8 and 8' on the display is within a predetermined distance, the current position data of the travel guidance system is read when the ignition switch is turned off (that is, when the vehicle finally returns to the starting point 8). The data is forcibly transferred to the data at the point of departure and corrected.

Conversely, when V, < V, the comparator! Since the I4aw) level signal is output from the goose, even if the ignition switch is turned off, the AND condition of the AND circuit 140 will not hold, and at that time, the data on the arithmetic unit s will be retained, and the display will remain unchanged. maintained. That is, in this case, the ninth busy vehicle whose distance between the departure point 8 on the display and the arrival point 8' is equal to or more than the predetermined distance R is not determined to be the ninth since it has finally returned to the departure point 8.

Therefore, the current position data on the travel guidance device is maintained as is.

In the above embodiment, when the driver returns to the starting point, the friend and 13$1 position data is corrected to the starting point data by detecting that the ignition switch is turned off. Please operate this manually.
You may.

In the above embodiment, the present invention is applied to a type of travel guidance device that performs deviation angle correction, and a large sword is explained. The application is not limited to this, as long as it is a type of travel guidance system that calculates In travel guidance equipment.

When the vehicle returns to the departure point, the calculation is made so that if the difference between the current position and the departure point is less than a predetermined distance, the vehicle's current position data is corrected to the departure point data, so the vehicle returns to the departure point. (The difference between the departure point and the arrival point when you return is zero), and as a result, the display is corrected, making the display appear unnatural. Since it is running, there is no problem with subsequent calculations or display.

[Brief explanation of the drawing]

Figure 1 shows the electrical circuit of a conventional vehicle guidance system $1
Figure z shows an example of a display on a map display as an indicator of a vehicle travel guidance device, and FIG. 3 shows an electrical circuit of an embodiment of the vehicle travel guidance device according to the present invention. 3...Phase detector, 3-distance sensor? %4-Distance counter %S...Arithmetic device,...Keyboard, marker display, l-bar graph, 11...Map display, 12...Position data, evening correction area setter, 13. ...Comparator, 14...Ignition off detector, ll5-...AND circuit patent applicant
Hiroo Suzuki, Patent Attorney, Nissan Motor Co., Ltd.

Claims (1)

[Claims] In a device that calculates and displays a current position based on a traveling direction of a vehicle, a distance calculation means that calculates a straight-line distance from a preset departure point to a current position;
a switch means that is operated when the vehicle arrives at the departure point; and when the straight line distance m is less than a predetermined distance and the switch means is operated, the data of the vehicle position is corrected to the preset departure point data. A travel guidance device for a vehicle, comprising: data correction means.