JPS5842482B2 - TV camera oriyoshita - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for guiding a moving object such as an automobile along a white line on a passage.

Various proposals have already been made regarding ways to automatically drive a car along a predetermined route.
They are not necessarily satisfactory.

The guidance method of the present invention displays the route to be guided by a moving object using a white line, detects the white line at an appropriate distance ahead of the moving object, calculates the deviation from the moving direction of the moving object, and calculates the deviation based on the deviation. The system controls the steering device and constantly detects a white line a certain distance ahead of the moving object, making it possible to guide the moving object and drive it automatically in conditions similar to human driving. The route to which the moving object is to be guided is simply indicated by a white line, and the device installed on the moving object can be relatively simple.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a case in which the present invention is applied to guiding a car traveling on a road will be described in detail with reference to the drawings.

As shown in FIGS. 1a and 1t), a pattern of white lines 3 is provided on a road 2 along which a car 1 travels along a route along which the car is to be guided.

On the vehicle 1, a white line ahead by an appropriate distance is detected, a deviation from the direction of travel of the vehicle is determined, and the steering wheel angle is controlled based on the deviation.

In order to detect the white line 3 at the point at the above distance,
A television camera 4 is installed on the vehicle, and a video signal processing circuit as shown in FIG. 2 is connected to the television camera 4.

To explain the signal processing circuit in Figure 2, first, a television camera projects an image of the front field of view as shown in Figure 3a, and the video signal is sent to a sampling circuit as shown by the dotted line in the figure. Only the signal along the scan line is sampled.

The location along the scanning line at which the signal is sampled in this sampling circuit is determined by the distance in front of the vehicle at which the white line is detected.

As shown in Figure 3, the sampled video signal has a large output in the part of the white line 3 for guiding the car because it is particularly bright, and a small output in the part that is darker than the other white lines. There is an output.

Therefore, this signal is compared with a reference voltage Eo in a comparison circuit.

This reference voltage EO is set in consideration of the brightness of the road surface and the white line in order to extract only the output corresponding to the white line from the video signal.

The signal shown in FIG. 3g from the comparator circuit indicates the position of the white line, and this signal is sent as a set signal to the flip-flop circuit (2) via a gate circuit (described later).

On the other hand, the direction of movement of the car in the image of the TV camera (Fig. 3g) is determined by the fixed orientation of the TV camera with respect to the car, and the direction of movement of the car is
Assuming that the vehicle passes through point A in the image in Figure g, how much the car's traveling direction deviates from the white line can be determined by the relative deviation between the position of point A and the white line on the sampled scanning line. I can do it.

Therefore, by delaying the horizontal synchronizing signal shown in FIG. 3 g generated in the horizontal synchronizing signal generating circuit for a certain period of time in a delay circuit, a signal indicating the traveling direction of the vehicle on the scanning line as shown in FIG. 3 e is generated. , which is sent as a reset signal to the flip-flop circuit (2).

When the flip-flop circuit (2) is operated by the set signal and reset signal described above, a pulse output as shown in FIG. This corresponds to the difference from the direction (point A).

Therefore, if the above pulse output is sent to the integrating circuit via the adding circuit and an output signal from the integrating circuit as shown in Figure 3g is obtained, the peak value of this output signal will be the difference between the position of the white line and the direction of travel of the car. In order to respond to Control the corners.

As a result, the steering wheel angle of the vehicle can be controlled in accordance with the deviation of the vehicle's traveling direction from the white line, and the vehicle can be guided along the white line.

Above, we have explained the case where the white line is on the left side with respect to the direction of travel of the car, but when the white line is on the right side with respect to the direction of travel of the car as shown in Figure 4g, the third
The signal indicating the direction of travel of the car in figure g is used as a set signal,
The output signal of the comparison circuit corresponding to the white line (Figure 4b) is used as a reset signal to operate the flip-flop circuit, and the pulse output of this flip-flop circuit (Figure 4g) is sent to the phase inversion circuit. (Fig. 4g)
), then enters the integrating circuit through the adding circuit.

An output signal as shown in FIG. 4g is obtained from the integrating circuit, and its peak value level is held in a peak value hold circuit.

The output signal of the peak value hold circuit (Fig. 4 f) has the opposite sign compared to the case where the white line is drawn on the left side of the car's direction of travel, so it is difficult to control the steering wheel angle based on the output signal. , the handle will naturally be rotated in the opposite direction.

In the signal processing circuit described above, the flip-flop circuit 1. For II, it is necessary that the set signal is input first, and then the reset signal is input.

In other words, the flip-flop circuit I uses the white line signal from the comparator circuit as a set signal, and uses the signal from the delay circuit indicating the direction of travel of the car as a reset signal, so after receiving the reset signal from the delay circuit, the flip-flop circuit I It is necessary to prevent the set signal from entering.

The gate circuit I connected to the comparison circuit performs this function.

Furthermore, the gate circuit (2) has the same purpose of preventing the set signal from the delay circuit from being input to the flip-flop circuit (2) after the reset signal from the comparator circuit has been input.

As is clear from the above explanation, according to the guidance method of the present invention, the route to which the moving object should be guided is displayed by a white line, and the white line is detected on the moving object to control the steering device. A mobile object can be guided along a predetermined route simply by installing a device that allows the moving object to follow a predetermined route.

[Brief explanation of drawings]

1a and 1b are a side view and a plan view for explaining the outline of the guidance method of the present invention, FIG. 2 is a block diagram showing an example of a signal processing circuit implementing the present invention, and FIG. 3 a -h and FIGS. 4a-f are explanatory diagrams regarding the process of signal processing. 1... Car, 2... Road, 3...
...White line, 4...TV camera.

Claims (1)

[Claims] 1. Display the route to be taken by a white line on the path of the moving object, install a television camera that displays the forward view on the moving object, and scan the white line in front of the moving object along the scanning line corresponding to the position where the white line should be detected. sample the video signal,
Using an output signal corresponding to the white line in this video signal and a signal indicating the moving direction of the moving object generated by delaying the horizontal synchronization signal of the television camera, the white line is set to the left with respect to the moving direction of the moving object. Depending on whether there is hail or hail on the right side, a separate flip-flop circuit is operated in which one of the two signals generated first is used as a set signal and the other signal is used as a reset signal, and this flip-flop circuit operates. The sign of one of the pulse outputs is inverted, thereby creating a time width that corresponds to the difference between the position of the white line and the moving direction of the moving object, and also determining whether the moving direction of the moving object is shifted to the left or right of the white line. The system generates a pulse output with the opposite sign, integrates this, holds its peak value, and uses this held output signal to automatically control the steering of the moving object according to the deviation from the white line. A method of guiding a moving object using a television camera.