JPH0260881A - Obstacle detection device for railway crossings - Google Patents

Abstract

PURPOSE:To securely detect an obstacle in a crossing by catching the sight of the railway crossing by a camera and memorying it, comparing present sight information with the memoried sight information by a sight change detecting means and detecting the obstacle by the change of the sights. CONSTITUTION:The sight of a crossing just after the pass of a train is caught by a television camera 1 and its sight information is memoried by a frame memory 3 via a read control unit 2 and it is renewed every passing of a train. A train progresses toward a crossing A, a crossing gate is let down, a signal is output to the read control unit 2 from a crossing gate control unit 2, sights nearby the crossing gate A just before the passing of a train caught by the camera 1 are selected and stored in a frame memory, sight information just after the passing of the train memoried by a sight change detecting unit 5 is compared with the present sight information, sight change volume more than a predetermined value is detected as an obstacle to notice it to the operator of the train via a control output unit 6. Like this way, an obstacle having a length less than 3 meters can be securely detected so that a safety operation can be attempted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a railway crossing obstacle detection device for ensuring the safe operation of trains at railway crossings.

[Conventional technology]

Figure 4 shows, for example, the "Signal" issued by Koyusha in 1985.
FIG. 2 is a configuration diagram showing a conventional railroad crossing obstacle monitoring device shown on pages 795 to 796 of the Japanese Patent Application Publication No. At the railroad crossing A, there is a light emitter IA that emits infrared rays on one side of the railroad crossing in the direction of the railroad track R.
and receivers 2^, 2^ for receiving infrared rays are installed on the same line at a predetermined height from the ground at appropriate intervals, and on the other side, a receiver 2^, 2^ for receiving infrared rays emitted by the emitter IA is installed. The light receiver 2B, 2B and the light receiver 2A,
Light emitters IB for projecting infrared rays to 2A are installed on the same line at a predetermined height from the ground at appropriate intervals. The light emitting side of the emitter IA faces the light receiving sides of the light receivers 2B and 2B across the railroad crossing A, and the light emitting side of the light emitter IB faces the light receiving sides of the light receivers 2A and 2A across the railroad crossing A. I'm letting you do it. These emitters, receivers IA, IB, 2
A, 2A, 2B.

2B is each number 3 at any position on the railroad crossing.
It is selected to be able to reliably detect an object passing through a railroad crossing, such as a motor vehicle, having a length of m or more, and also determine the direction in which the infrared rays are projected. These emitters, receiver IA
, IB, 2A, 2A, 2B, and 2B are each connected to the control section 3 by a control line (not shown).

In this level crossing obstacle monitoring device, when the infrared light emitted by the light emitters IA and IB and crossing the level crossing A is interrupted for a predetermined period of time or more, the control unit 3 detects this and operates the obstacle detection relay. This activates a warning device such as a special signal light emitter to issue a warning to trains proceeding towards level crossing A.

[Problem to be solved by the invention]

Conventional level crossing obstacle monitoring devices are configured as described above, so that objects with a length of 3 m or less will not enter the level crossing A.
If infrared rays continue to exist between each other across railroad crossing A, there is a problem that the presence of the object can be detected because the infrared rays are not blocked, and obstacles at the railroad crossing cannot be accurately monitored. .

SUMMARY OF THE INVENTION In view of such problems, it is an object of the present invention to provide a railway crossing obstacle detection device that reliably detects obstacles at a railway crossing, regardless of their length.

[Means for Solving the Problems] The obstacle detection device for a railroad crossing according to the present invention includes a camera that captures the situation at a railroad crossing, a means for storing situation information obtained from this camera, and a current situation. A situation change detection means is provided for detecting a situation change by comparing the information with the stored situation information.

[Effect]

The camera captures the situation at the railroad crossing. The means for storing the situation information captured by the camera is stored.

The situation change detection means compares the stored situation information and the current situation information. The situation change detection means detects an obstacle at a railroad crossing.

Therefore, obstacles are detected regardless of their length.

〔Example〕

The present invention will be described in detail below with reference to drawings showing embodiments thereof. FIG. 1 is a block diagram of a railway crossing obstacle detection device according to the present invention. The output of the television camera 1 that captures the scene of a railroad crossing (hereinafter referred to as a railroad crossing) is input to a reading control section 2 that selects a frame memory 3.4 and reads scene information into it. is provided with an output from a barrier control unit 8 which works in conjunction with a barrier, which will be described later, provided at the level crossing and outputs an output when the barrier is down. And reading control section 2
The output of each frame memory 3.4 is given to a frame memory 3 for storing scene information and a frame memory 4 for temporarily storing current scene information, and the output of each frame memory 3.4 is used to detect the difference between the two scene information. The situation change detection unit 5 is provided with the following information. Further, the output of the situation change detection section 5 is given to a control output section 6 which outputs an alarm when a significant change is detected.

The output of the frame memory 4 is given to a CRT 7, which is a display that displays an image based on the current situation information.

Figure 2 is a front view of the railroad crossing. An alarm 10 is installed at an example of the approach entrance of level crossing A to notify of the arrival of a train.
Further, an automatically opening/closing barrier 11 for preventing entry to the level crossing A is installed, with its base serving as an example of a level crossing entrance.

A television camera 1 is installed above the railroad crossing A with its light-receiving side facing downward so as to be able to capture the entire situation around the railroad crossing. This television camera is designed to capture the state of the level crossing within the time period from when the barrier 1 comes down to immediately after the train passes through the level crossing.

Next, the operation of the railway crossing obstacle detection device constructed as described above will be explained with reference to FIGS. 1, 2, and 3. FIG. 3 is a flowchart showing the detection procedure in the situation change detection section.

In this railroad crossing obstacle detection device, every time a train passes through a railroad crossing, scene information from a television camera 1 that captures the scene of the railroad crossing immediately after passing is transferred to a frame memory 3 in which it is to be stored.
The reading control unit 2 selects the frame memory 3 to store the situation information, and therefore, the frame memory 3 always stores information about the latest train that has passed through the railroad crossing. The situation information immediately after the change is updated and stored.

However, if the train is now proceeding toward level crossing A and the barrier 11 is lowered to prevent it from entering the level crossing A, the barrier controller 8 sends a signal indicating that the barrier has been lowered. is given to the reading control unit 2. Thereby, the read control unit 2 captures the scene near the railroad crossing A by the television camera 1, reads the scene information, selects the frame memory 4 in which the current scene information is to be stored, and stores the current scene information therein. is temporarily stored, and an image is displayed on the CRT 7 based on the current scene information.The frame memories 3 and 4 output the stored scene information in the same pixel order, and display the image on the CRT 7 based on the current scene information. The scene change detection unit 5 initializes the pixel coefficient value of the counter to zero (Sl).Subsequently, the pixel shading obtained from the scene information stored in the frame memory 3, for example, is applied to the scene change detection unit 5. From the value a (i, j), subtract the gray value b (i, j) of the pixel of the current scene information that corresponds to this pixel to obtain the gray difference value c (i, j) (S2). , compare the shading difference value c (f, j) with the constant T1 set to remove the influence of circuit noise. For example, that pixel is counted and the pixel coefficient value d is increased by one (S4). Note that if the constant T is below, the counting operation is not performed. In this way, the gradation difference values C of all pixels in one screen are sequentially reduced. Then, for each pixel with a gradation difference value C that is equal to or greater than the constant T6, settings are made to remove the influence of image noise when the TV camera 1 captures the respective gradation difference value C and a moving object such as a tree within the field of view. Compare the size with the constant T2 (S
5). Thereafter, an obstacle is detected when the number of pixels d of the grayscale difference value C, which is equal to or greater than the constant T2, exceeds a predetermined value that is set in advance to determine that an obstacle exists (S6 ). That is, if the grayscale change of the same pixel based on the stored scene information and the current scene information covers a wide range of pixels, an obstacle has been detected.

Upon detecting the obstacle, the situation change detection section 5 outputs an output and sends it to the control output section 6, and the output of the control output section 6 is sent to an alarm section (not shown) indicating that there is an obstacle on the railroad crossing A. inform the train driver of the As a result, before the train arrives at level crossing A, the driver can perform the necessary operations to safely operate the train and avoid collisions with obstacles.

In this way, the situation near the railroad crossing is captured with a TV camera, and the change in the situation between immediately after the train passes the railroad crossing and before the train arrives at the railroad crossing is determined, regardless of the length of the obstacle. This means that obstacles at railroad crossings can be detected accurately.

(Effects of the Invention) As detailed above, according to the present invention, obstacles are detected from changes in the scene captured by the camera, so the length of
The problem of not being able to detect obstacles with a length of m or less is resolved, and obstacles at railroad crossings can be reliably detected. Therefore, a highly reliable obstacle detection device can be provided, and an excellent effect can be achieved that can greatly contribute to the safe operation of trains.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the obstacle detection device for a railroad crossing according to the present invention, FIG. 2 is a front view of the railroad crossing, FIG. 3 is a flowchart showing the detection procedure of the situation change detection unit, and FIG. 4 is a conventional one. FIG. 2 is a schematic diagram of a railroad crossing obstacle monitoring device. 1...TV camera 2...Reading control section 3, 4.
...Frame memory 5...Situation change detection unit 8...
- Breaker control unit In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A lamella that captures the situation at a railroad crossing, a means for storing the situation information obtained from this camera, and a method for detecting changes in the situation by comparing the current situation information and the stored situation information. 1. An obstacle detection device for a railway crossing, comprising: a scenery change detection means, and configured to detect an obstacle within the railway crossing based on an output of the scenery change detection means.