KR20220160308A - Apparatus and method for detecting fire based on polarized light scattering - Google Patents

Abstract

Provided is a device for detecting a fire based on polarized light scattering. The device includes: a chamber into which smoke is introduced; a light emitting unit which polarizes and irradiates light into the space within the chamber; a light receiving unit for polarizing and receiving light scattered by smoke introduced into the chamber; a control unit for controlling the operation of the light emitting unit and the light receiving unit; and a fire determination unit comprising a polarization scattering matrix based on the incident light signal value by the light emitting unit and the scattered light signal value by the light receiving unit, and classifying fire smoke and non-fire smoke based on a comparison result with a previously derived detection signal value.

Description

Apparatus and method for detecting fire based on polarization scattering {APPARATUS AND METHOD FOR DETECTING FIRE BASED ON POLARIZED LIGHT SCATTERING}

The present invention relates to an apparatus and method for detecting a fire based on polarization scattering.

A general fire detector is a device that determines whether or not there is a fire by detecting heat and smoke generated in the event of a fire. These fire detectors include a heat detection method and a smoke detection method.

Thermal sensing methods include a constant temperature type that detects a fire when the ambient temperature of the sensor rises above a certain level, and a differential type that operates when the temperature increase rate exceeds a threshold value.

In addition, smoke detection methods include an ionization method for measuring a change in an ion current value by smoke and a photoelectric method for detecting scattering of light by smoke particles.

On the other hand, recently, the use of photoelectric fire detectors for rapid detection of fire is increasing. Such a photoelectric fire detector has a structure in which smoke flows into a chamber inside the detector and when light is scattered by the smoke particles, the scattered light is sensed and a fire alarm is generated.

However, the conventional photoelectric fire detector has a non-fire alarm that determines that it is a fire and issues an alarm even when fine particles other than fire, such as cooking smoke, cigarette smoke, water vapor, and fine dust, that occur in daily life, flow in as well as actual smoke. There are problems that occur frequently.

Publication No. 10-2021-0049661 (2021.05.06)

The problem to be solved by the present invention is to detect a fire by using the scattering characteristics of light with respect to smoke particles. It is to provide a device and method for detecting.

However, the problem to be solved by the present invention is not limited to the above problem, and other problems may exist.

An apparatus for detecting a fire based on polarization scattering according to a first aspect of the present invention for solving the above problems is a chamber into which smoke is introduced, a light emitting unit that polarizes and irradiates light into a space within the chamber, and an inflow into the chamber. A polarization scattering matrix is configured based on a light receiving unit that polarizes and receives light scattered by smoke, a control unit that controls operations of the light emitting unit and the light receiving unit, and a signal value of incident light by the light emitting unit and a signal value of scattered light by the light receiving unit, and a fire determination unit that classifies fire smoke and non-fire smoke based on a comparison result with the derived signal value for detection.

In some embodiments of the present invention, the light emitting unit includes a plurality of first polarization filters for polarizing light in a plurality of different directions, and the light receiving unit detects light polarized through the first polarization filters scattered by smoke. A second polarization filter for polarizing and receiving scattered light may be included.

In some embodiments of the present invention, the light emitting unit may include a plurality of light emitting units for emitting light composed of a plurality of wavelengths, and the light receiving unit may include a plurality of light receiving units for separately receiving light of the plurality of wavelengths. can

In some embodiments of the present invention, the light emitting unit radiates light consisting of a plurality of wavelengths and a plurality of light emitting units and a plurality of first polarization polarizing light consisting of the plurality of wavelengths in a plurality of different directions. The light receiving unit includes a second polarization filter for polarizing scattered light scattered by smoke from the light polarized through the first polarization filter, and converts the scattered light polarized by the second polarization filter into the plurality of wavelengths. A plurality of light receiving units for separately receiving light may be included.

In some embodiments of the present invention, the control unit may periodically control blinking of the light emitting unit and periodically receive control of the light receiving unit.

In some embodiments of the present invention, the fire determination unit configures the polarization scattering matrix by performing matrix multiplication based on the incident light signal value and the scattered light signal value, wherein each element value of the polarization scattering matrix is fire smoke and non-fire smoke It can be configured to be discriminated according to.

In some embodiments of the present invention, the fire determination unit stores the detection signal value derived in advance for each type of fire smoke and non-fire smoke, and fire smoke based on a comparison result with each element value of the polarization scattering matrix. and non-fire smoke.

In addition, a method for detecting a fire based on polarization scattering according to a second aspect of the present invention includes controlling the light emitting unit to periodically flicker to irradiate polarized light into a space in a chamber through which smoke is introduced; periodically receiving and controlling a light receiver to polarize and receive light scattered by smoke introduced into the chamber; constructing a polarization scattering matrix based on the incident light signal value by the light emitting unit and the scattered light signal value by the light receiving unit; and distinguishing between fire smoke and non-fire smoke based on a comparison result between each element value of the polarization scattering matrix and a previously derived detection signal value.

A computer program according to another aspect of the present invention for solving the above problems is combined with a computer that is hardware to execute a method for detecting a fire based on polarization scattering, and is stored in a computer readable recording medium.

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

According to one embodiment of the present invention described above, it is possible to reduce false alarms due to non-fire alarms caused by life smoke through a fire detection device and method having a fire and non-fire distinguishing function, and to prevent firefighters from being dispatched by mistake in advance. There are advantages to being able to do it.

The 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 description below.

1 is a diagram showing an example for vertical polarization.
2 is a diagram illustrating a spherical coordinate system.
3 is a diagram showing the shape of each polarization.
4 is a schematic diagram of a general photoelectric fire detector.
FIG. 5 is a view for explaining how the photoelectric fire detector of FIG. 4 operates when smoke particles are introduced.
6 is a diagram for explaining a fire detection device according to an embodiment of the present invention.
7 is a flow chart of a fire detection method according to an embodiment of the present invention.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only these embodiments are intended to complete the disclosure of the present invention, and are common in the art to which the present invention belongs. It is provided to fully inform the person skilled in the art of the scope of the invention, and the invention is only defined by the scope of the claims.

Terminology used herein is for describing the embodiments and is not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. As used herein, "comprises" and/or "comprising" does not exclude the presence or addition of one or more other elements other than the recited elements. Like reference numerals throughout the specification refer to like elements, 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 components, these components 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 element mentioned below may also be the second element within the technical spirit of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with meanings commonly understood by those skilled in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless explicitly specifically defined.

Hereinafter, a fire detection device 100 (hereinafter referred to as a fire detection device) based on polarization scattering according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6 .

Polarization is an interpretation of light as an electromagnetic wave in terms of wave optics, and refers to a phenomenon in which the electric or magnetic field constituting the wave vibrates in a specific direction when the electromagnetic wave propagates. Here, light can be interpreted as an electric field, so if only the electric field is considered, light is generally a mixture of light vibrating in all directions perpendicular to the direction of travel, but polarization uses a specific filter to vibrate only in a specific direction. . That is, polarization can be said to be light that vibrates only in a specific direction.

축 방향으로 진행하는 빛은

성분

와

성분

로 표현될 수 있다. 여기에서

와

는 각 방향에 대한 빛의 크기,

는 진동 주파수,

는 시간,

는 파수,

는 위치,

는 두 성분 사이의 위상차를 나타낸다. 이때,

또는

가 0이면 선형 편광(수직, 수평)이고,

이고,

또는

이면 원형 편광(우편광, 좌편광),

와

가 0이 아니고

이고,

이면 타원형 편광이 된다. 도 1은 수직 편광에 대한 예시를 도시한 도면이다.Polarization is generally divided into linear polarization, circular polarization, and elliptical polarization. Since light is a transverse wave,

Light traveling in the axial direction

ingredient

Wow

ingredient

can be expressed as From here

Wow

is the magnitude of light in each direction,

is the vibration frequency,

time,

is the watchman,

is the location,

represents the phase difference between the two components. At this time,

or

is 0, linear polarization (vertical, horizontal),

ego,

or

Backside circular polarization (right polarized light, left polarized light),

Wow

is not 0

ego,

If it is, it becomes elliptically polarized light. 1 is a diagram illustrating an example of vertical polarization.

Meanwhile, the Stokes variable is a value introduced to describe the polarization state of electromagnetic waves including light. 2 is a diagram illustrating a spherical coordinate system. Referring to the spherical coordinate system of FIG. 2, the relationship between the Stokes variable, the amount of light, and the parameters of the polarization ellipse can be expressed as Equation 1 below.

[Equation 1]

는 전체 광량,

는 편광도,

는 도 2의 3차원 공간상 구면 좌표계의 각도이다. 식 1에서

앞의 상수 2는 어떤 편광 타원이든

회전시 구분할 필요가 없음을 나타내고,

앞의 상수 2는 타원의 반축 길이가

회전과 연계되어 바뀜을 나타낸다. 이러한 스토크스 변수들은 식 2와 같이 스토크스 벡터의 형태로 나타낼 수 있다.From here

is the total amount of light,

is the degree of polarization,

Is the angle of the spherical coordinate system in the 3-dimensional space of FIG. in Equation 1

The previous constant 2 is any polarization ellipse

Indicates that there is no need to distinguish when rotating,

The preceding constant 2 is the length of the semi-axis of the ellipse

In conjunction with rotation, it represents change. These Stokes variables can be expressed in the form of a Stokes vector as shown in Equation 2.

[Equation 2]

Table 1 below summarizes Equation 2 according to the type of polarization. At this time, FIG. 3 is a diagram showing the shape of each polarization.

form of polarization no polarization horizontal polarization vertical polarization +45° polarization -45° polarization right circular polarization left circular polarization

I One One One One One One One

Q 0 One -One 0 0 0 0

U 0 0 0 One -One 0 0

V 0 0 0 0 0 One -One

When light is incident on a surface or material, phenomena of transmission, reflection, and scattering appear. When the above Stokes vector is expressed for scattering, the following equation is shown.

[Equation 3]

은 입사광을 나타내고

는 산란광을 나타낸다.At this time, in Equation 3

represents the incident light

represents the scattered light.

4 is a schematic diagram of a general photoelectric fire detector. FIG. 5 is a view for explaining how the photoelectric fire detector of FIG. 4 operates when smoke particles are introduced.

A photoelectric fire detector according to the prior art is composed of a light emitting part and a light receiving part, and the light blocking wall or the light emitting part and the light receiving part are arranged at a different angle to maintain a certain angle inside the chamber, so that the light of the light emitting part is detected by the light receiving part when there is no smoke. It is structured to prevent this from happening.

As such, the internal chamber of the conventional photoelectric fire detector has a structure in which the light emitting part does not interfere with the light receiving part in an environment without smoke particles, so that the light source is not detected in the light receiving part, but when smoke particles are introduced into the detector, smoke The light source generated in the light emitting unit by the particles is scattered by the smoke particles, and the light source is input to the light receiving unit, and the light receiving unit reacts. Since these conventional photoelectric fire detectors respond by aerosol particles, they respond not only to smoke caused by fire but also to everyday life smoke such as kitchen cooking smoke, cigarette smoke, water vapor, and dust, resulting in frequent occurrence of non-fire alarms. have.

In order to solve this problem, one embodiment of the present invention can distinguish between fire and non-fire using polarization scattering characteristics of light.

6 is a diagram for explaining a fire detection device 100 according to an embodiment of the present invention.

A fire detection device 100 according to an embodiment of the present invention includes a chamber 110, a light emitting unit 120, a light receiving unit 130, a control unit 140, and a fire determination unit 150.

In the chamber 110, an inspection space through which smoke flows is formed, and light is irradiated into the inspection space through the light emitting unit 120, and scattered light scattered by the smoke is received by the light receiver 130.

The light emitter 120 polarizes and radiates light into the space within the chamber 110, and the light receiver 130 polarizes and receives light scattered by smoke introduced into the chamber 110.

In one embodiment, the light emitting unit 120 may include a plurality of first polarization filters that polarize light in a plurality of different directions. For example, the plurality of first polarization filters polarize and irradiate light in a first direction, and polarize and irradiate light in a second direction different from the first direction.

In an exemplary embodiment, the light receiver 130 includes a second polarization filter that polarizes and receives scattered light scattered by smoke from light polarized through the first polarization filter. For example, the plurality of second polarization filters polarize and receive light scattered by smoke in a first direction, and polarize and receive light in a second direction different from the first direction.

In this case, the first and second directions of the light emitting unit 120 and the light receiving unit 130 may be the same as or different from each other.

In addition, in one embodiment of the present invention, the light emitting unit 120 may include a light emitting unit for radiating light composed of a plurality of different wavelengths, and the light receiving unit 130 is irradiated with light having a plurality of wavelengths. It may be configured to include a plurality of light receiving units for separately receiving a plurality of wavelengths.

In this case, the fire detection device 100 according to an embodiment of the present invention may be configured by simultaneously using a plurality of polarization filters and a plurality of wavelengths. That is, the light emitting unit 120 may be composed of a plurality of polarizations of at least two or more types, may be composed of a plurality of wavelengths different from the wavelength of the light source, or may be composed of adding a plurality of polarization functions for each wavelength. Similarly, the light receiving unit 130 may be composed of a plurality of polarized light and may be configured to receive a plurality of wavelengths according to the wavelength range of the light emitting part.

Meanwhile, a wavelength band used in an embodiment of the present invention may be selected and applied by a user according to a place where the fire detection device 100 is installed, an arrangement location, and an arrangement environment.

The control unit 140 controls the operation of the light emitting unit 120 and the light receiving unit 130 . In one embodiment, the control unit 140 controls the light emitting unit 120 to blink periodically, and periodically controls whether a detection signal is generated by the light receiving unit 130 or not.

At this time, when the smoke particles are introduced into the chamber 110, the light irradiated through the first polarization filter of the light emitting unit 120 is scattered by the smoke particles, and the scattered light passes through the second polarization filter of the light receiving unit 130. The light is received through and collected by the control unit. The scattered light signal collected in this way is a signal value corresponding to SC in Equation 3, and a signal value corresponding to in is a value set through initial measurement of the configuration.

The fire determination unit 150 configures a polarization scattering matrix based on the incident light signal value from the light emitting unit 120 and the scattered light signal value from the light receiving unit 130, and based on the comparison result with the previously derived detection signal value. to distinguish between fire smoke and non-fire smoke.

의 매트릭스를 구성한다. 여기에서 편광 산란 매트릭스의 각 요소값인

값은 화재 연기 및 비화재 연기에 따라 그 값의 차이가 발생한다.In one embodiment, the fire determination unit 150 performs matrix multiplication by applying the incident light signal value and the scattered light signal value to Equation 3

make up the matrix of Here, each element value of the polarization scattering matrix is

The value differs according to fire smoke and non-fire smoke.

에 대한 임계값 또는 일정 범위의 값을 도출하고, 이 도출된 값을

으로 설정하여 저장한다. 그리고 실제 상황에서 연기 입자에 의해 발생된

값을 미리 저장된

값과 비교하여 화재 연기에 대해서는 경보를 발생하고, 비화재 연기에 대해서는 경보 발생을 유보하도록 할 수 있다. 이때, 검출용 신호값

에 대한 임계값 또는 일정 범위는 사용자에 의해 선택 및 변경이 가능하다.As an embodiment, the fire determination unit 150 may store detection signal values derived in advance for each type of fire smoke and non-fire smoke, and the comparison result between the detection signal value and each element value of the polarization scattering matrix Based on this, fire smoke and non-fire smoke can be distinguished. That is, the fire determination unit 150 conducts a preliminary test for each type of fire smoke and non-fire smoke.

Derive a threshold value or a certain range of values for

Set to and save. And in the real situation, the smoke particles generated by

pre-stored values

By comparing the value, it is possible to generate an alarm for fire smoke and defer alarm for non-fire smoke. At this time, the signal value for detection

A threshold value or a certain range for can be selected and changed by the user.

7 is a flow chart of a fire detection method according to an embodiment of the present invention. Meanwhile, each step shown in FIG. 7 may be understood to be performed by the fire detection device 100 of FIG. 6, but is not necessarily limited thereto.

First, the light emitting unit is controlled to blink periodically to polarize and irradiate light into a space in the chamber into which smoke is introduced (S110).

Next, the light receiver periodically receives and controls the light scattered by the smoke introduced into the chamber to polarize and receive light (S120).

to the next. A polarization scattering matrix is constructed based on the incident light signal value by the emitter and the scattered light signal value by the light receiver (S130), and based on the comparison result between each element value of the polarization scattering matrix and the previously derived detection signal value, Smoke and non-fire smoke are classified (S140).

Meanwhile, in the above description, steps S110 to S140 may be further divided into additional steps or combined into fewer steps according to an embodiment of the present invention. Also, some steps may be omitted if necessary, and the order of steps may be changed. In addition, even if other omitted contents, the contents of the fire detection device 100 of FIG. 6 may be applied to the contents of FIG. 7 as well.

The fire detection method according to an embodiment of the present invention described above may be implemented as a program (or application) to be executed in combination with a computer, which is hardware, and stored in a medium.

The above-mentioned program is C, C++, JAVA, Ruby, C, C++, JAVA, Ruby, which the processor (CPU) of the computer can read through the device interface of the computer so that the computer reads the program and executes the methods implemented as a program. It may include a code coded in a computer language such as machine language. These codes may include functional codes related to functions defining necessary functions for executing the methods, and include control codes related to execution procedures necessary for the processor of the computer to execute the functions according to a predetermined procedure. can do. In addition, these codes may further include memory reference related codes for which location (address address) of the computer's internal or external memory should be referenced for additional information or media required for the computer's processor to execute the functions. have. In addition, when the processor of the computer needs to communicate with any other remote computer or server in order to execute the functions, the code uses the computer's communication module to determine how to communicate with any other remote computer or server. It may further include communication-related codes for whether to communicate, what kind of information or media to transmit/receive during communication, and the like.

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

The above description of the present invention is for illustrative purposes, and those skilled in the art can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be construed as being included in the scope of the present invention. do.

100: fire detection device
110: chamber
120: light emitting unit
130: light receiving unit
140: control unit
150: fire judgment unit

Claims (1)

A device for detecting fire based on polarization scattering,
a chamber into which smoke enters;
A light emitting unit that polarizes and irradiates light into the space within the chamber;
A light receiving unit for polarizing and receiving light scattered by smoke introduced into the chamber;
A control unit for controlling the operation of the light emitting unit and the light receiving unit; and
A fire determination that configures a polarization scattering matrix based on the incident light signal value by the light emitting unit and the scattered light signal value by the light receiving unit, and classifies fire smoke and non-fire smoke based on the comparison result with the detection signal value derived in advance. including wealth,
fire detection device.

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