KR20220063436A - Obstacle detection system for screen door using infrared cameras - Google Patents

Abstract

Disclosed in the present specification is an obstacle detection system capable of monitoring the entire area of a screen door. According to the present specification, the obstacle detection system may comprise: a plurality of infrared cameras installed on a screen door; an image data receiving unit for receiving image data from each of the plurality of infrared cameras; and an obstacle detecting unit for detecting an obstacle in each image data received by the image data receiving unit.

Description

OBSTACLE DETECTION SYSTEM FOR SCREEN DOOR USING INFRARED CAMERAS

The present invention relates to an obstacle detection system using an infrared camera, and more particularly, to a system mounted on a screen door installed in a railway platform to detect an obstacle of a railway or a screen door.

The content described in this section merely provides background information for the embodiments described herein and does not necessarily constitute prior art.

In general, in the case of a specific company or organization, a video surveillance system including hundreds or thousands of cameras is built and operated, and a huge amount of money is consumed to build such a system. Some of the multiple camera input images installed in this way are recorded in the image storage device for a certain period of time, and some are sent to the monitoring center of the general command room so that they can be monitored in real time by at least one security manager.

At this point, no matter how well trained and competent the security administrator is, it is impossible to pay full attention to more than one or two things at the same time, and even monitoring and managing can only focus on a few minutes at a time. Due to this, the majority of the numerous images displayed on the monitor pass without observation. This situation is like having hundreds of eyes but no brain to process that information.

On the other hand, urban railroads are used by many passengers, and since an accident can lead to a major accident, it is possible to reduce human life and property damage to a minimum according to the initial response in the event of an accident. To this end, a monitoring system using CCTV for monitoring urban railroads has been proposed, but it is a passive system that simply receives an image and outputs it to the monitor, and the manager waits for 24 hours and directly monitors to identify the emergency situation. This also has a problem in that the manager cannot closely and intensively monitor it.

In addition, the existing CCTV surveillance system of urban railroads has the advantage of being able to express the image closest to the truth without distortion because it is mainly analog signal type image information, while a coaxial cable for image information, a control cable for camera control, and power supply Each is composed of a power cable that supplies

Laid-open Patent Publication No. 10-2011-0075794, 2011.07.06

An object of the present specification is to provide an obstacle detection system capable of monitoring the entire area of a screen door.

The present specification is not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

Screen door obstacle detection system according to the present specification for solving the above problems, a plurality of infrared cameras installed on the screen door; an image data receiver configured to receive respective image data from the plurality of infrared cameras; and an obstacle detecting unit for detecting an obstacle in each image data received by the image data receiving unit.

According to one embodiment of the present specification, the plurality of infrared cameras may be provided with a pair of infrared cameras for each opening of the screen door, and each pair of infrared cameras may be installed on both ends of the opening. .

In this case, the plurality of infrared cameras may be installed to photograph the platform and the track in the upper region of the screen door.

According to an embodiment of the present specification, the obstacle detecting unit may distinguish a platform area and a track area in each image data, and detect whether there is an obstacle in the track area.

According to another embodiment of the present specification, the obstacle detecting unit may distinguish a platform area from a track area by using a difference in brightness in each image data.

According to another exemplary embodiment of the present specification, the obstacle detecting unit may detect a straight line in a central region in each image data, and divide the platform area and the track area based on the detected straight line.

According to another embodiment of the present specification, the obstacle detecting unit may distinguish the platform area from the track area using pixels in which an infrared marker installed between the track and the platform in each image data is photographed.

The screen door obstacle detection system according to the present specification may further include a screen door control unit configured to control opening and closing of an opening part of the screen door. In this case, the screen door control unit may control the opening to be opened when the obstacle detecting unit determines that there is an obstacle in the track area.

The screen door obstacle detection method according to the present specification comprises receiving respective image data from a plurality of infrared cameras installed on the screen door, and detecting an obstacle in each image data, wherein the processor (a) a platform in each image data dividing an area and a track area; (b) determining whether there is an obstacle in the track area; and (c) opening the opening of the screen door when there is an obstacle in the track area.

The screen door obstacle detection method according to the present specification may be implemented in the form of a computer program written to perform each step in a computer and recorded in a computer-readable recording medium.

Other specific details of the invention are included in the detailed description and drawings.

According to one aspect of the present specification, it is possible to more accurately detect the presence or absence of an obstacle that is difficult to determine only with a conventional point type photosensor or a two-dimensional planar type laser sensor.

According to another aspect of the present specification, an obstacle in a track area that is relatively dark compared to a platform area may be detected using an infrared camera.

Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a block diagram schematically showing the configuration of a screen door obstacle detection system according to the present specification.
2 is a reference diagram in which a plurality of infrared cameras are installed on a screen door.
3 is a reference diagram of an area photographed by an infrared camera.
4 is a reference diagram for dividing a platform and a track area.
5 is a diagram illustrating an example of pixel coordinate system transformation.
6 is an exemplary view in which an IR marker is installed on the platform.
7 is an exemplary view showing people on the platform and the track.
8 is a flowchart of a screen door obstacle detection method according to the present specification.

Advantages and features of the invention disclosed herein, and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present specification is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the present embodiments allow the disclosure of the present specification to be complete, and those of ordinary skill in the art to which this specification belongs. It is provided to fully inform those skilled in the art (hereinafter, 'those skilled in the art') the scope of the present specification, and the scope of the present specification is only defined by the scope of the claims.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the scope of the present specification. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other components in addition to the stated components.

Like reference numerals refer to like elements throughout, and "and/or" includes each and every combination of one or more of the recited elements. Although "first", "second", etc. are used to describe various elements, these elements are not limited by these terms, of course. These terms are only used to distinguish one component from another. Accordingly, it goes without saying that the first component mentioned below may be the second component within the spirit of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used herein will have the meaning commonly understood by those of ordinary skill in the art to which this specification belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless specifically defined explicitly.

Spatially relative terms "below", "beneath", "lower", "above", "upper", etc. It can be used to easily describe the correlation between a component and other components. Spatially relative terms should be understood as terms including different directions of components during use or operation in addition to the directions shown in the drawings. For example, when a component shown in a drawing is turned over, a component described as "beneath" or "beneath" of another component may be placed "above" of the other component. can Accordingly, the exemplary term “below” may include both directions below and above. Components may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to orientation. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram schematically showing the configuration of a screen door obstacle detection system according to the present specification.

Referring to FIG. 1 , the screen door obstacle detecting system 100 according to the present specification may include a plurality of infrared cameras 110 , a data receiving unit 120 , and an obstacle detecting unit 130 .

The plurality of infrared cameras 110 are installed on the screen door. A screen door is a door installed between a track and a platform and serves to prevent a passenger from falling onto the track. When the train stops at the correct position on the track, the opening of the screen door is opened so that passengers can get on and off.

2 is a reference diagram in which a plurality of infrared cameras are installed on a screen door.

According to one embodiment of the present specification, the plurality of infrared cameras 110 may be provided with a pair of infrared cameras for each opening of the screen door. In addition, each pair of infrared cameras may be installed at both ends of the opening. Since two infrared cameras form a pair and are installed in each opening, the accuracy of obstacle detection can be improved, and even if one of the infrared cameras fails, the other one can detect it.

3 is a reference diagram of an area photographed by an infrared camera.

According to an embodiment of the present specification, the plurality of infrared cameras may be installed to photograph the platform and the track in the upper region of the screen door. Through this, the platform area and the track area may be photographed together in the image captured by each infrared camera.

Referring back to FIG. 1 , the image data receiver 120 may receive respective image data from the plurality of infrared cameras. The image data receiver 120 may be a so-called switching hub for data communication. In addition, the image data receiving unit 120 may be a component of the so-called management office monitoring server.

The obstacle detecting unit 130 may detect an obstacle in each image data received by the image data receiving unit 120 . The obstacle detection unit 130 may be a component of the so-called management office monitoring server. The management office monitoring server may include a plurality of displays for displaying each image to the manager. In addition, the management office monitoring server may output one image by concatenating each image in conjunction with the physical location of the infrared camera installed on the screen door.

Meanwhile, the obstacle detecting unit 130 may determine whether an obstacle exists by excluding the background in the image. In particular, the platform area and the track area may be photographed together in the image, and the obstacle detection unit 130 distinguishes the platform area and the track area in each image data, and detects whether there is an obstacle in the track area. .

According to an embodiment of the present specification, the obstacle detecting unit 130 may distinguish a platform area from a track area by using a difference in brightness in each image data. In general, the platform area has a relatively bright brightness due to the indoor lighting, and the track area has relatively dark brightness because a separate lighting device is not installed. Accordingly, the platform area and the track area can be distinguished by using the difference in brightness in the image captured by the infrared camera.

According to another embodiment of the present specification, the obstacle detecting unit 130 may detect a straight line in a central region within each image data, and may divide the platform area and the track area based on the detected straight line. The infrared camera according to the present specification is installed on the screen door. The screen door is generally installed in the boundary line area between the platform and the track. Accordingly, the boundary line area between the platform and the track may be captured even in the image captured by the infrared camera installed on the screen door. Preferably, the boundary line area will be captured in the central area of the image captured by the infrared camera.

4 is a reference diagram for dividing a platform and a track area.

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으로 변환)된 예시(도 5의 (b))를 확인할 수 있다. r-θ평면의 한 점은 직선을 나타내므로 교차점이 존재한다면 X-Y평면에서의 점들이 한 직선 위에 있다는 것을 의미한다. 따라서, Edge detection 알고리즘을 거친 영상에서 직선이 아닌 오브젝트들은 검출되지 않으므로 승강장과 선로 사이의 경계선만 추출할 수 있다.Referring to FIG. 4 , it can be confirmed that the platform and the track appear in the image in the image captured by the infrared camera. In this case, in order to distinguish the platform from the track, the central region of the image (eg, 1/3 of the entire image) may be designated as the region of interest (ROI). In addition, the edge of the ROI region can be detected using an edge detection algorithm. Since the edge detection algorithm is known to those skilled in the art, a detailed description thereof will be omitted. What we are trying to find here is the boundary line that separates the platform and the track, and the other edges are unnecessary edges. Accordingly, in order to detect a straight line in an image, a set of points having a straight line tendency more accurately, the points on the image are converted from the Cartesian coordinate system to the polar coordinate system, and the tendency can be analyzed to detect the straight line on the image. In more detail, all straight lines passing through a point (pixel: x, y) expressed in a Cartesian coordinate system can be expressed as xcosθ + ysinθ = r. 5 is a diagram illustrating an example of pixel coordinate system transformation. Referring to FIG. 5, the pixel coordinates of the existing XY plane ((a) of FIG. 5) are converted into r and θ planes (points

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Converted to ) can be seen in the example (Fig. 5 (b)). A point in the r-θ plane represents a straight line, so if there is an intersection point, it means that the points in the XY plane are on a straight line. Therefore, since non-linear objects are not detected in the image that has been subjected to the edge detection algorithm, only the boundary line between the platform and the track can be extracted.

6 is an exemplary view in which an IR marker is installed in the platform.

According to another embodiment of the present specification, the obstacle detecting unit 130 may distinguish the platform area from the track area using pixels in which an infrared marker installed between the track and the platform in each image data is photographed. To this end, the IR marker may be installed at a point dividing the track and the platform at regular intervals (see Fig. 6 (a)). Since the IR marker has a characteristic of retroreflecting infrared rays (refer to (b) of FIG. 6), the brightness value of the pixel at the point where retroreflection is higher than the brightness value of the pixel at the point where no retroreflection in the image taken with the infrared camera has The magnitude of the brightness value is relatively large (refer to (c) of FIG. 6). The obstacle detecting unit 130 may detect the position of the IR marker in the image by using a pixel area greater than a specific threshold value and detect it as a boundary line by connecting it with a straight line. The IR marker is not limited to a circular marker, and various IR markers such as IR tape and IR spray are possible.

On the other hand, the screen door obstacle detection system 100 according to the present specification may further include a screen door control unit (not shown) for controlling the opening and closing of the opening of the screen door. In addition, when the obstacle detecting unit 130 determines that there is an obstacle in the track area, the screen door control unit may control the opening to be opened.

7 is an exemplary view showing people on the platform and the track.

Referring to FIG. 7A , the passenger exists only in the platform area and does not exist in the track area. In this case, the obstacle detection unit 130 may determine that there is no obstacle in the track area, and the screen door control unit may control the opening to close.

Referring to (b) of FIG. 7 , it is a case in which a passenger moves from a platform to a train. In this case, the passenger is present in the platform area and the track area at the same time. Accordingly, the obstacle detecting unit 130 may determine that an obstacle exists in the track area, and the screen door control unit may control the opening to be opened.

Referring to FIG. 7C , it is a case in which a passenger moves from a train to a platform. In this case, since the passenger is present in the track area, the obstacle detecting unit 130 may determine that an obstacle exists in the track area, and the screen door controller may control the opening to be opened.

8 is a flowchart of a screen door obstacle detection method according to the present specification.

The screen door obstacle detection method according to the present specification corresponds to a method in which the obstacle detection unit 130 included in the screen door obstacle detection system according to the present specification determines an obstacle. The obstacle detection unit 130 includes a processor, an application-specific integrated circuit (ASIC), another chipset, a logic circuit, and a register known in the art to execute a determination method, calculation, and various control logic to be described below. , a communication modem, a data processing device, and the like. In addition, when the determination logic to be described below is implemented in software, the obstacle detecting unit may be implemented as a set of program modules. In this case, the program module may be stored in the memory and executed by the processor.

Referring to FIG. 8 , in step S110 , a platform area and a track area in each image data may be divided. In the next step S120, it may be determined whether there is an obstacle in the track area. When there is an obstacle in the track area (YES in step S120), the process may proceed to step S121. In step S121, the opening of the screen door may be opened. On the other hand, when there is no obstacle in the line area (NO in step S120), the process may proceed to step S122. In step S122, the opening of the screen door may be closed.

Meanwhile, the screen door obstacle detection method according to the present specification may be implemented in the form of a computer program. The computer program is C/C++, C#, JAVA, Python that a processor (CPU) of the computer can read through a device interface of the computer in order for the computer to read the program and execute the methods implemented as a program , may include code coded in a computer language such as machine language. Such code may include functional code related to a function defining functions necessary for executing the methods, etc., and includes an execution procedure related control code necessary for the processor of the computer to execute the functions according to a predetermined procedure. can do. In addition, the code may further include additional information necessary for the processor of the computer to execute the functions or code related to memory reference for which location (address address) in the internal or external memory of the computer to be referenced. there is. In addition, when the processor of the computer needs to communicate with any other computer or server located remotely in order to execute the above functions, the code uses the communication module of the computer to determine how to communicate with any other computer or server remotely. It may further include a communication-related code for whether to communicate and what information or media to transmit and receive during communication.

The storage medium is not a medium that stores data for a short moment, such as a register, a cache, a memory, etc., but a medium that stores data semi-permanently and can be read by a device. Specifically, examples of the storage medium include, but are not limited to, ROM, RAM, CD-ROM, magnetic tape, floppy disk, and an optical data storage device. That is, the program may be stored in various recording media on various servers accessible by the computer or in various recording media on the computer of the user. In addition, the medium may be distributed in a computer system connected to a network, and a computer-readable code may be stored in a distributed manner.

As mentioned above, although the embodiments of the present specification have been described with reference to the accompanying drawings, those of ordinary skill in the art to which this specification belongs can realize that the present invention may be embodied in other specific forms without changing the technical spirit or essential features thereof. you will be able to understand Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

100: screen door obstacle detection system 110: infrared camera
120: data receiving unit 130: obstacle detecting unit

Claims (10)

a plurality of infrared cameras installed on the screen door;
an image data receiver configured to receive respective image data from the plurality of infrared cameras; and
and an obstacle detection unit for detecting an obstacle in each image data received by the image data receiving unit. The method according to claim 1,
The plurality of infrared cameras is provided with a pair of infrared cameras for each opening of the screen door,
Each pair of infrared cameras is a screen door obstacle detection system installed at both ends of the opening. 3. The method according to claim 2,
The plurality of infrared cameras are installed to take pictures from the upper area of the screen door toward the platform and the railroad obstacle detection system for the screen door. The method according to claim 1,
The obstacle detection unit,
A screen door obstacle detection system that divides a platform area and a track area in each image data and detects whether there is an obstacle in the track area. 5. The method according to claim 4,
The obstacle detection unit,
A screen door obstacle detection system that distinguishes the platform area from the track area using the difference in brightness in each image data. 5. The method according to claim 4,
The obstacle detection unit,
A screen door obstacle detection system that detects a straight line in a central area in each image data and divides a platform area and a track area based on the detected straight line. 5. The method according to claim 4,
The obstacle detection unit,
A screen door obstacle detection system that distinguishes the platform area from the track area by using pixels photographed with an infrared marker installed between the track and the platform in each image data. The method according to claim 1,
It further includes; a screen door control unit for controlling the opening and closing of the opening of the screen door;
The screen door control unit controls the opening portion to be opened when the obstacle detection unit determines that there is an obstacle in the track area. A method of receiving respective image data from a plurality of infrared cameras installed on a screen door and detecting an obstacle in each image data, the processor comprising:
(a) classifying a platform area and a track area in each image data;
(b) determining whether there is an obstacle in the track area; and
(c) opening an opening of the screen door when there is an obstacle in the track area; screen door obstacle detection method comprising a. A computer program written in a computer to perform each step of the method for detecting an obstacle on a screen door according to claim 9 and recorded in a computer-readable recording medium.

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