JPS58206912A - Display for traveling locus - Google Patents

Abstract

PURPOSE:To enable the automatic correction of the deviation in the point of place before the error increases, by processing the traveling locus of a vehicle from a azimuth sensor and a distance sensor arithmetically, and displaying the traveling locus on a display on which a map is displayed. CONSTITUTION:The data on the map recorded in a data recording-reproducing device 8 is written into an image memory 2 by the operation of an arithmetic device 1 when an input device 11 is operated. The recorded program data is further written into the random access memory in the device 1. The arithmetic device judges the program data automatically, reads out the map and displays the same on a display 9 when the traveling locus arrives at the road end. The distance between the coordinate point of that time and the coordinate point at each road end is calculated with the device 1 and the traveling locus is corrected automatically to the road end that makes said distance shortest. The traveling locus is further corrected during traveling by tracing up as the azimuth error per traveling distance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses an arithmetic device such as a microcomputer to read out a map written in an external memory and display it on a display such as a cathode ray tube (CRT). The present invention relates to a driving trajectory display device that calculates the driving trajectory of a vehicle from a distance sensor and displays the driving trajectory on a display displaying a map.

In this type of conventional travel trajectory display device.

Even if you are driving on the road shown on the map, due to errors in the direction sensor and distance sensor, if you continue driving for a while after adjusting the starting point, your trajectory may deviate from the road shown on the display. Therefore, it was difficult to accurately display the current location on the map. Furthermore, as you drive, when you reach the periphery of the displayed map, the adjacent map is automatically read out from the map memory and displayed, and the driving trajectory display device is equipped with an automatic map switching device that continues to display the trajectory. Because it is cumulative, practical accuracy cannot be ensured, and the driver has to correct the current location to the correct point on the map each time, resulting in insufficient operability.

The present invention solves this problem and provides a travel trajectory display device that can automatically correct the deviation of the current location on the map due to errors in the direction sensor and distance sensor before the error becomes large. It is.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of its main parts. In the same figure, 1
are microcomputers, read-only memory (hereinafter referred to as ROM), and random access memory (hereinafter referred to as RAM).
It is an arithmetic device that consists of Reference numeral 2 denotes one or more image memories composed of RAM. The image memory is connected to the arithmetic unit 1 by a pass line, and also has a shift register 3 with parallel input and serial output.
It is connected to the. A clock circuit 4 generates reference clock pulses necessary for operating the arithmetic unit 11 and image memory 2, as well as data load pulses and shift clock pulses for the shift register 3.

5 is a perinoeral interface adapter (hereinafter referred to as PIA) which functions as an interface between the arithmetic unit 1 and peripheral devices. 6 is a distance sensor that outputs a pulse proportional to the rotation speed of the axle. Reference numeral 7 denotes an orientation sensor composed of a gyrocator, a geomagnetic sensor, and the like. The direction sensor 7 is a sensor that detects the rotation angle from the direction of the earth's magnetic field or the angular velocity of the vehicle in order to detect the direction in which the vehicle is traveling. 8 is a data recording and reproducing device such as a cassette type magnetic recording and reproducing device, a floppy disk, and an optical disk.

Image data and program data of a plurality of maps are recorded in this data recording/reproducing device 8. Reference numeral 9 denotes a display made up of a CRT, liquid crystal display, etc., which displays a map and the driving route.

10 is a monitor interface for converting the output of the shift register 3 into a video signal.

Reference numeral 11 denotes an input device through which the driver inputs necessary information to the arithmetic unit 1 using a keyboard or a voice recognition device.

Next, the operation of this embodiment will be explained. First, by operating the input device 11, the map data recorded in the data recording/reproducing device 8 is written into the image memory 2 by the operation of the arithmetic device 1. Furthermore, the program data recorded in the data recording/reproducing device 8 is written to the random access memory in the arithmetic device 1. The amount of image memory is determined by the number of images on the display and the colors that can be displayed (this is determined by the memory output (256), assuming that the pixel configuration of the display 9 is 266 dots horizontally and 192 dots vertically).
92 = 49152 bit string 6 is made up of nodes. FIG. 2 shows an example of a road map of a certain city where roads are arranged in a grid pattern. When the road map of this city is represented by maps A, B, C, and D surrounded by one-dot chain lines, the map data of each map is recorded in the data recording and reproducing device 8.

Here, it is assumed that the car is stopped at a point S on the map A.

The image data of the map A read out from the data recording/reproducing device 8 is written into the image memory 2 by the input device 11, and the map A is displayed on the display 9.

This is shown in Figure 3 ←). At the same time as reading the image data of map A, necessary program data of map A is written from the data recording/reproducing device 8 to the RAM in the arithmetic device 1.

The program data includes the numbers of adjacent maps and the coordinates of roads around the map.

The specific program data is shown below.

Xl, X2. B.D.

C9X3. X4. x5 (a, 0) (b, O) (c, 0) (x o * d) (”o e e) (xo
+ f ) (q, yo) (h, yo) (i, yo) (o
, 5) (otk) (o, j) first xl, x2. B, D, C9x3. x4. x5 indicates the number of adjacent maps, each in the northern part of map A.

Indicates map numbers for Northeast, East, Southeast, South, Southwest, and Northwest. The coordinates shown below are the origin (0,0) at the northwestern edge of the map.
and the northeast end, southeast end, and southwest end (" o
e O) (x o t y o')' (0* y
o), and each point a, b, c,...l, which indicates the coordinates of a road that intersects with the surroundings of the map, is (-, 0) (b, o) (C, O) (!0.d) (!0,
8) (!01f ) (q , yo) (h, yo) (i,
yo) (o, j) (otk) (oIi).

Now, a case will be described in which the current location of the vehicle, point S, is set on the road of map A using the input device 11, and then the vehicle starts driving toward the destination point shown in FIG. When the coordinates of the starting point S are (S-work, SA), the position (x, y) of the car after one hour is the speed in the X-axis direction v! , if the velocity in the a-axis direction is Va, then (Kf vxat, Kfvydt>-c
shown. Cocoa, K is the scale factor, vx, va are the distance sensor and direction sensor, i), = i) g i nθ,'
l), = 1) coSll T desired meralel V, which is the velocity of each component, is the velocity per unit time, and θ indicates the direction of travel of the car.

Now, when displaying the progress of the vehicle, that is, the travel trajectory, it is assumed that the trajectory indicated by the dotted line in FIG. 3 (-) is displayed due to errors in the direction sensor 7 and the distance sensor 6.

When the travel trajectory reaches the road edge between e and f, the program data is automatically determined and the map B is transferred to the data recording and reproducing device 8.
The data is read out and displayed on the display 9. This is the third
It is shown in Figure 0)). Then, as we continue to display the driving trajectory with a difference of the same t%, the distance becomes further and further away from the road we were originally traveling on, as shown by the dotted line in Figure 3 (0)). In the invention, the distance between the coordinate point V and the coordinate point of each road edge when the travel trajectory reaches the periphery of the map A is calculated by the calculation device 1, and the travel trajectory is placed at the road edge where this distance is the shortest. Correct automatically. That is, the point v(xo, y) at the map edge of the travel trajectory is compared with each road edge. The distance to point a is ρa, and the distance to point b is 2b.

The distance to each point at this time is shown in the table below.

From the margin below, the point with the shortest distance among 1a421 is determined to be the regular driving point, and in the case of map A, the 0 point is determined to be the driving point, and when switching to map B. By setting the starting point of the map to 0, the map is automatically corrected each time the map is automatically changed to prevent errors from accumulating on the display of the road traveled on the subsequent travel trajectory. ]) and display it as shown in the dashed-dotted line.

Furthermore, the distance ρ traveled on the map A and the distance β between points 7 and 0. 7, the travel trajectory is corrected when tracing the map B by setting (1,/Q as the azimuth error per unit travel distance).

That is, when the current location of the travel trajectory is indicated by (x2tY2),
2=x 0′+Kf Vs i n (θ+t a n
−” :' ) d tY2”yo' +KfVco
By displaying the point at the point indicated by s (θ+tan-'!-'')dt, the accuracy of the travel trajectory can be automatically improved.

As described above, the present invention is capable of displaying the travel trajectory of a vehicle with high precision, and has very large effects.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a main part of an embodiment of the present invention, FIG. 2 is a diagram showing an example of a road, and FIG. 3 (b) is a diagram showing an example of a map displayed on a display. 1... Arithmetic unit, 2... Image memory, 3
......Shift register, 4...Clock circuit, 6...Distance sensor, 7...Direction sensor, 8...Data recording Playback device, 9.
... Display, 1o ... Monitor interface, 11 ... Input device. Figure 1 of the agent, patent attorney Toshio Nakao and one other person! Figure 2 31! l

Claims (2)

[Claims] (1) An arithmetic device including an arithmetic circuit such as a microcomputer, a read-only memory, and a readable/writable memory, a data recording/reproducing device for recording and reproducing image data such as maps and program data, and a cathode ray tube. etc., an image memory for recording images to be displayed on the display, an input device such as a key board for giving timely instructions to the arithmetic unit, a distance sensor for detecting the regular distance and traveling direction of the vehicle, and The vehicle is equipped with a direction sensor, and displays a map read out from a data recording and reproducing device on the display, and also displays a travel trajectory on the display superimposed on the map as the vehicle travels.
When the travel trajectory reaches the end of the displayed map, the data recording and reproducing device reads out the adjacent map that includes the current location of the travel trajectory and displays it on the display, and the map end of the travel trajectory or The arithmetic unit processes the coordinates near the edge and the coordinates of the road edge drawn on the map, automatically moves the travel trajectory to the nearest road, and displays the starting point of the trajectory after the map has been switched. A travel trajectory display device characterized in that it is configured to make corrections on a road displayed on the road. (2) A device that calculates the ratio of the distance traveled on the displayed map until reaching the end of the map displayed on the display and the distance from the end of the map indicated by the travel trajectory to the correct end of the road. In addition to calculating the correction coefficient of the direction sensor per unit traveling distance, the next adjacent map is displayed on the display and the traveling trajectory is continuously calculated.When displaying, calculate the direction of travel obtained from the direction sensor. The travel trajectory display device according to claim 1, wherein the travel trajectory display device is configured to calculate and display the next trajectory on the map by taking into account a correction coefficient.