JP3044978B2 - Aircraft parking position detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects the position of an aircraft approaching a parking spot after landing at an airport or the like, and detects the position information of the aircraft, the direction to proceed, the remaining distance to the stop position, and the like. The present invention relates to an aircraft parking position detecting device for notifying a pilot operating the aircraft.

[0002]

2. Description of the Related Art Conventionally, in order to stop at a predetermined stop position in a parking spot after an aircraft has landed at an airport and has entered a parking spot, a marshaler is generally used for a pilot operating the aircraft. An instructor called using a flag, etc., tells the direction the aircraft should travel,
When stopping, the timing of stopping is notified.

[0003]

Since recent aircraft have become larger in size, and once stopped, it is extremely difficult to correct the position by themselves, so it is important to stop accurately with a single stop operation. ing. However, until now, there has been no other way but to rely on a human signal to detect the position of the aircraft with high accuracy and to provide the pilot with appropriate and effective information. In general, there is a problem that the working environment is poor at airport parking spots, especially where aircraft enter, and the labor costs for holding marshalas are enormous.

According to the present invention, in such a situation, the position of the aircraft is accurately detected, and further,
It is intended to provide a means for providing appropriate and effective information.

[0005]

The present invention SUMMARY OF THE INVENTION includes an imaging device for imaging an aircraft coming enters the parked spot, and binarization circuit for binarizing the video signal from the imaging device, the binary A tire detection circuit for detecting a tire position from a digitized image, a position calculator for detecting a position of an aircraft from the detected tire position, and a providing means for providing the pilot with position information calculated by the position calculator Are provided.

[0006]

The aircraft parking position detecting device according to the present invention accurately detects an aircraft approaching a parking spot, and
It serves to provide the pilot operating the aircraft with useful information about the course and the stop position.

[0007]

【Example】

Embodiment 1 FIG. FIG. 1 is a conceptual diagram showing one embodiment of the present invention.
FIG. 2 is a block diagram showing one embodiment of the present invention. FIG.
As shown in FIG. 1, an aircraft parking position detecting device (hereinafter referred to as the present device) according to the present invention is a high-definition camera with a lens 1 attached to a wall or the like facing an aircraft T entering a parking position. 2 and a display device 8 incorporating a video input circuit and the like. FIG. 2 is a block diagram illustrating in detail the configuration of the present apparatus shown in the conceptual diagram of FIG. In the figure, 1 is a lens, 2 is a high-definition camera, 3 is a video input circuit, 4 is a difference circuit, 5 is a binarization circuit, 6 is a tire detection circuit, 7 is a position detector, 8 is a display device, 9 is An illuminance detector, an aperture adjustment mechanism, an image storage device, a reference pattern, a control circuit for controlling the operation of the present device. The apparatus according to the present invention captures the aircraft T entering the parking position by the lens 1,
An image is taken by the high definition camera 2. In recent years, it has become common to use an optical lens and a camera as a means for capturing an image of an aircraft, but this portion may be any imaging device that captures an image of the aircraft as an image. Also, in this embodiment, in order to increase the accuracy,
Although a high-definition camera with 0 pixels and 750 pixels in the vertical direction was used, a normal ITV camera may be used if accuracy is not so much required. The image captured by the high-definition camera 2 is input by the video input circuit 3 and digitized. The digitized image is subtracted by a difference circuit 4 from a reference image stored in advance in an image storage device 11, and is binarized by a binarization circuit 5. In this embodiment, the difference circuit is used to improve the quality of the binarization. However, when the brightness of the parking spot does not change so much, the difference circuit is not necessarily required. 2 by the binarization circuit 5
The tire position is detected by the tire detection circuit 6 using the reference pattern 12 from the binarized binary image. The position detector 7 calculates the position of the aircraft from the detected tire position, and displays and outputs the aircraft position on the display device 8. In the present embodiment, the positional relationship between the remaining distance to the stop position of the aircraft and the approach guide line of the aircraft is shown. The image digitized by the video input circuit 3 is input to the difference circuit 4 and also to the illuminance detector 9, and the detected illuminance information is input to the aperture adjustment mechanism 10 to optimally adjust the aperture of the lens 1. . In this embodiment, the illuminance detector 9 and the aperture adjustment mechanism 10 are used to improve the quality of the binarization. However, when the brightness of the parking spot does not change so much, the illuminance detector 9 and the aperture are not necessarily used. No adjustment mechanism 10 is required.

The high-definition camera 2 is designed to have a high resolution of 1500 horizontal pixels and 750 vertical pixels.
By rotating the image by 0 ° and capturing an image, it is possible to capture an image of a distant aircraft with one camera without lowering the accuracy. In particular, in order to suppress the detection accuracy at the position where the aircraft stops to 30 cm or less, 1500 horizontal pixels are required. The control circuit 13 causes the image storage device 11 to store, as a reference image, an image on a non-aircraft parking just before the aircraft enters the parking position. The difference image after the extraction is an image in which only the aircraft is mainly extracted as shown in FIG. The difference image is binarized by an appropriate fixed binary level set in advance by a binarization circuit 5, and a dark portion such as a tire is further extracted from an image in which only an aircraft is extracted. In general, the ground of an airport is often paved with a bright color, and is illuminated at night, so that the tire portion of the difference image from which only the aircraft is extracted is almost always extracted as a dark image. Therefore, if binarization is performed using a fixed binary level that extracts only a dark portion, it is possible to easily obtain a binarized image in which only the tire portion is cut out. The tire detection circuit 6 detects a position of the binary image having the highest correlation with the reference pattern 12 as a tire position. In this embodiment, when the reference pattern 12 is superimposed on the binary image obtained by the binarization circuit 5, a position where the degree of coincidence between the reference pattern 12 and black and white is highest is detected as a tire position. Reference pattern 1
For example, it was found from a field test that high detection accuracy could be obtained by using a pattern as shown in FIG. 3, for example. FIG. 4 shows an example in which tire detection is performed using the reference pattern 12. In FIG. 4, part A is a tire part. In this case, although the tire portion is slightly smaller than the reference pattern, when the reference pattern shown in FIG. 4A and the reference pattern overlap as shown in FIG. In FIG. 4, the hatched portions are portions where the black and white do not match. On the other hand, in the part B of FIG. 4B, when the reference pattern shown in FIG. 4A overlaps the reference pattern as shown in FIG. 4B, the reference pattern and the black and white most match, but the black and white do not match. The ratio of the hatched portion is larger than that of the tire portion. By the way, the direction of travel of the aircraft is clear, and there is always a certain level of illuminance at all times of the day and night to make it easy for pilots to maneuver. There are few dark parts.
As a result of the field test, it is found that the tire detection rate is greatly improved by using the tire detection circuit 6 as a detection logic for finding a portion having a high correlation with the reference pattern 12 from the front of the tire toward the tire. Was. The relationship between the tire position detected by the tire detection circuit 6 and the position of the high-definition camera is shown in FIG. 5, and the position detector 7 calculates the position of the aircraft using the following equation. D = h · tan (θ1 + θ2) h: height of the camera θ1: depression angle of the camera = arctan ( l / h) θ2: angle of tire deviation from the center of the camera

Embodiment 2 FIG. Now, the binarization level given for binarizing the difference image may be a simple fixed value as in the above-described embodiment, but various measures can be taken to further improve the quality of the binary image. FIG. 6 shows an example in which a minimum value detection circuit 14 is provided to improve the quality of a binary image. In this embodiment, the minimum value is detected from the difference image after the difference is obtained by the difference circuit 4, and a value obtained by adding a predetermined value based on the minimum value is used as a binarization level. I have. Normally, the tire portion is the darkest in the difference image, and gives the minimum value of shading. Therefore, even if the brightness of the entire image changes due to a weather difference or a time difference by the method as in the present embodiment, the tire portion is stable. Only the tire part can be easily binarized by distinguishing it from the other parts. FIG. 7 is an example of the difference image of the present embodiment. As shown in FIG. 7, the tire portion is the darkest and gives the minimum value in this screen. In the present embodiment, the value obtained by adding the value of 10% of the dynamic range of the gradation of the image based on the minimum value is used as the binarization level so that only the tire portion is stably distinguished from the other portions. Could be transformed.

Embodiment 3 FIG. FIG. 8 shows an example in which a frequency distribution calculation circuit 15 is provided to improve the quality of a binary image. In this embodiment, the frequency distribution of each density level is calculated as shown in FIG. 9 (b) from the difference image after the difference is obtained by the difference circuit 4, and the density level of this frequency distribution is calculated. The first minimum value from the darkest is used as the binarization level. Normally, the tire part is the darkest in the difference image,
With the method as in this embodiment, binarization can be easily performed by distinguishing only the tire portion from other portions.

Embodiment 4 FIG. FIG. 10 shows an example in which an illuminance calculation circuit 16 is provided to improve the quality of a binary image. In this embodiment, the average illuminance of the entire image is obtained from the difference image after the difference is obtained by the difference circuit 4, and a value set in advance is added to the average illuminance and used as a binarization level. For example, as shown in FIG. 11, normally, when the entire background is bright, such as during a clear day, the tire portion is also bright,
Also, when the entire background is dark as in the case of cloudy sunset, the tire portion is also dark. Therefore, the average illuminance of the entire image is obtained, and a tire binarization level obtained by adding a preset value to the average illuminance is used. Binarization can be easily implemented by distinguishing only the part from other parts. FIG.
1 (a) and (b) show the difference image and the frequency distribution when the entire background is dark, and FIGS. 11 (c) and 11 (d) show the difference image and the frequency distribution when the entire background is bright.

Embodiment 5 FIG. FIG. 12 shows an example in which a projection circuit 17 is provided for detecting a tire portion. In this embodiment, 2
A mapping circuit 17 obtains a mapping in the horizontal direction and / or the vertical direction on the binary image binarized by the value conversion circuit 5, and provides this mapping information to the tire detection circuit 6. . FIG. 13 is an example of the projection obtained in this embodiment. In this embodiment, in a binary pattern binarized at an appropriate binarization level set in advance by the binarization circuit 5, a characteristic pattern of a tire portion, that is, a horizontal projection is performed. Is detected as a tire portion by detecting a pattern in which two peaks of the same degree appear and only one peak appears in the vertical direction.

[0013]

As described above, according to the present invention , the position of the aircraft is determined.
Detect and provide pilot information such as aircraft position
can do.

[Brief description of the drawings]

FIG. 1 is a diagram showing the concept of Embodiment 1 of the present invention.

FIG. 2 is a configuration diagram showing a first embodiment of the present invention.

FIG. 3 is a diagram showing a reference pattern according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating an example in which tire detection is performed using a reference pattern according to the first embodiment of the present invention.

FIG. 5 is a diagram showing a positional relationship between a tire position and a high-definition camera according to the first embodiment of the present invention.

FIG. 6 is a diagram showing a second embodiment of the present invention.

FIG. 7 is a diagram illustrating a difference image according to the second embodiment of the present invention.

FIG. 8 is a diagram showing a third embodiment of the present invention.

FIG. 9 is a diagram illustrating a difference image and a frequency distribution according to a third embodiment of the present invention.

FIG. 10 is a diagram showing a fourth embodiment of the present invention.

FIG. 11 is a diagram illustrating a difference image and a frequency distribution according to a fourth embodiment of the present invention.

FIG. 12 is a diagram showing a fifth embodiment of the present invention.

FIG. 13 is a diagram showing a projection according to a fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lens 2 High-definition camera 3 Video input circuit 4 Difference circuit 5 Binary circuit 6 Tire detection circuit 7 Position calculator 8 Display device 9 Illuminance detector 10 Aperture adjustment mechanism 11 Image storage device 12 Reference pattern 13 Control circuit

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Toshinobu Kato 325 Kamimachiya, Kamakura-shi Kamakura Works, Mitsubishi Electric Corporation (56) References JP-A-7-2191 (JP, A) JP-A-6-199298 (JP, A) JP-A-6-199297 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01B 11/00-11/30 102 B64F 1/22-1/24 G06T 1/00 H04N 7/18

Claims (11)

(57) [Claims] An imaging device for imaging an aircraft entering a parking spot after landing at an airport or the like; a binarization circuit for binarizing a video signal output from the imaging device; A tire detection circuit that detects the tires of the aircraft from the output of the binarization circuit, a position calculator that calculates the position of the aircraft from the tire positions detected by the tire detection circuit, and aircraft position information calculated by the position calculator And a providing means for providing information for the aircraft to reach a predetermined stop position in a parking spot for a pilot operating the aircraft. 2. An illuminance detector for detecting the illuminance of a parking spot, and a control circuit for controlling a magnitude of an output signal of the imaging device based on the illuminance detected by the illuminance detector. An aircraft parking position detecting device as described in the above. 3. An image storage device for storing an image of a parking spot without an aircraft, and a difference circuit for obtaining a difference between an image stored in the image storage device and an output from the imaging device. 2. The aircraft parking position detecting device according to claim 1, wherein the device is provided at a stage preceding the circuit. 4. The aircraft parking detection according to claim 1, further comprising a reference pattern of an aircraft tire, wherein the tire detection circuit detects a tire having the highest correlation with the reference pattern as an aircraft tire. apparatus. 5. A minimum value detection circuit for detecting a value of an image in a darkest part of an image input to a binarization circuit, and adding a fixed value to the minimum value detected by the minimum value detection circuit. 5. The aircraft parking position detecting device according to claim 1, wherein the determined value is used as a binarization level of a binarization circuit. 6. A frequency distribution calculation circuit for calculating a frequency distribution of gray levels for each pixel of an image input to a binarization circuit, wherein the first minimum value of the density level of the frequency distribution from the darkest one is used. The aircraft parking position detecting device according to any one of claims 1 to 4, wherein the value is used as a binarization level of a binarization circuit. 7. An illuminance calculation circuit for calculating an average illuminance of the entire image from a difference image of a difference circuit, wherein a value obtained by adding a preset value to the average illuminance is used as a binarization level of a binarization circuit. The aircraft parking position detecting device according to any one of claims 1 to 4, wherein: 8. An image output from a binarization circuit is provided with horizontal, vertical,
Alternatively, it has a projection detection circuit that detects both projections, and the tire detection circuit detects a tire position by detecting a predetermined pattern from the projection detected by the projection detection circuit. An aircraft parking position detecting device according to claim 1. 9. A reference comprising two spaced rectangular shapes.
Holding the reference pattern and before the output of the binarization circuit.
The best correlation between the reference pattern and the aircraft
Characterized by detecting its position as a tire
The aircraft parking position detecting device according to claim 1. 10. The imaging device according to claim 1, wherein the horizontal pixels are rotated 90 degrees.
High resolution of 1500 pixels or more horizontally installed in a rotated state
5. A camera according to claim 1, further comprising a camera.
An aircraft parking position detecting device as described in the above. 11. The binarizing circuit according to claim 11, wherein said tire detecting circuit comprises:
From the image ahead of the aircraft at the output of the road
Detecting tire position toward the image
An aircraft parking position detecting device according to any one of claims 1 to 4, wherein