RU2767989C1 - Method of determining boundaries and dimensions of section of detection zone of passive infrared detector used to detect and identify type of intruder - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: invention relates to methods of security monitoring of an area and can be used in cases of using one passive two-beam infrared detection means on a road section for detecting an intruder and identifying its type. Method consists in installation of one passive infrared detector (ID) at height of 0.3 meters from the ground level near the road at a distance of not less than 40 % of the maximum length of the detection zone (DZ) so that its width at the point of intersection with the road is not less than 1 meter. Optical axis of the double-beam ID DZ is oriented at such horizontal and vertical angles that its projection in the horizontal plane crosses the road section at angle of 90 degrees, and the lower boundary of the double-beam ID DZ was located parallel to the ground level. When the intruder crosses the double-beam ID DZ, the latter switches to alarm mode, during the time spent in which the useful detector signal is recorded. Further, the detector uses an algorithm for determining the type of the intruder from the form of the useful signal: if the first pulse of the useful signal generated when the intruder crosses the detection zone of the detection system, has one local maximum or minimum - a pedestrian intruder, if the first pulse of the useful signal generated when the intruder crosses the detection zone, has two local maximum or minimum - intruder on wheeled vehicle. Information on the type of the intruder is transmitted by the detection system to an information collection and processing system (ICPS), which registers an alarm signal and information on the type of the intruder from the detection system.

EFFECT: reduced error in identifying the type of intruder, regardless of the shape of the vehicle profile.

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Description

The invention relates to methods of security monitoring of the area and can be used in cases where one passive two-beam infrared detection means is used on a road section to detect an intruder and recognize his type.

As a rule, the route of movement of the intruder on the ground passes through the existing network of trails and roads. It is important for the response forces not only to know the fact of violation and the direction of movement of the intruder, but also its type (on foot or on a vehicle), which makes it possible to correctly assess the possible range of speeds of the intruder, the nature of his actions and, based on the data obtained, choose the most rational solutions for his search. and subsequent detention [1].

For signaling cover of the network of trails and roads, passive infrared detection tools (CO) with a two-beam detection zone (ZO) with a length (L) of up to 50 meters (Fig. 1) are widely used. Analysis of CRMs used for the protection of terrain, foreign production ("Rembass", "Rembass 2" - USA, CLASSIC - Great Britain, etc.) and domestic (RS-IK - "Polyus-ST", Radiy BRK-IK - "Umirs" , Mongoose - "Steelsoft", etc.) shows that they use a typical pyroelectric transducer consisting of two differentially connected half-segments (DUAL), the geometric dimensions of the SO and the main characteristics of these tools have values close to each other [2-6].

A known method of recognizing the type of intruder with an infrared detection tool, which consists in installing one CO near the road at a distance of at least 40% of the maximum length of the detection zone (ZO) so that its width at the intersection with the road is at least 1 meter; orienting the SO so that the axis of its two-beam SA intersects the road section at an angle of 90 degrees; transition of SO into alarm mode when the intruder crosses its two-beam ZO; records of the CO of the useful signal during the entire time it is in the alarm mode; application in the CO of the algorithm for determining the type of intruder by the shape of the useful signal: the first pulse of the useful signal generated when the intruder crosses the zone has one local maximum or minimum - the intruder on foot, the first pulse of the useful signal generated when the intruder crosses the zone has two local maxima or minima - offender on a wheeled vehicle; transmission to the CO of information about the type of intruder - a foot intruder or an intruder on a vehicle to the SSSI; ensuring registration of the alarm signal and information about the type of intruder from the SO [7].

The known method has a slight error when crossing the section of the SO with vehicles whose profile is close to an elongated rectangular shape between the wheel axles - more than 4 meters (Fig. 2). In turn, when crossing the SO section with vehicles that have a profile significantly different from an elongated rectangular shape between the wheel axles: a pickup truck, three-door SUVs, etc., the recognition error is quite high (Fig. 3).

It is known that signal generation in PIKSO is based on the registration of changes in the total heat flux from the object and the background of COs located inside the SO [2, 3]. The authors note that if an object that is unevenly heated along its length moves in the SO, the process of signal formation will change significantly. Which in turn affects the receipt of two local maxima in the first pulse of the useful signal, which is the main feature underlying the recognition of the type of intruder in the known method (Fig. 4) [7]. So, if the SO SS crosses a car with a body profile shape close to an elongated rectangular one, the result will be close to that described in the method for recognizing the type of intruder with an infrared detection tool (Fig. 4) [7].

If the SO SS crosses a car with a body profile shape that differs significantly from an elongated rectangular one from one wheel axle to another, then thermal contrast fluctuations that occur due to the upper part entering the detection zone, which differs significantly from the lower part of the profile, can prevent the formation of two local maxima in the first pulse of the useful signal (Fig. 1, 3, 5).

The aim of the invention is to obtain the possibility of recognizing the type of intruder detected by a two-beam passive infrared detection means with a minimum recognition error, regardless of the shape of the vehicle profile.

To achieve this goal, a method has been developed for determining the boundaries and sizes of the PIR detection zone area used to detect and recognize the type of intruder, which consists in installing one PIR detection tool at a height of 0.3 meters from the ground level near the road at a distance of at least 40 % of the maximum length of the detection zone (ZO) so that its width at the intersection with the road is at least 1 meter; orienting the optical axis of the two-beam SO with such horizontal and vertical angles that its projection in the horizontal plane intersects the road section at an angle of 90 degrees, and the lower boundary of the two-beam SO with is parallel to the ground level; CO transition to the alarm mode when the intruder crosses its two-beam SO CO; records of the CO of the useful signal during the entire time it is in the alarm mode; application in the CO of the algorithm for determining the type of intruder by the shape of the useful signal: the first pulse of the useful signal generated when the intruder crosses the JO has one local maximum or minimum - the intruder on foot, the first pulse of the useful signal generated when the intruder crosses the JO has two local maxima or minimum - an intruder on a wheeled vehicle; transmission of information about the type of intruder by the SO - a foot intruder or an intruder on a vehicle to the information collection and processing system (ISOS); ensuring registration of the alarm signal and information about the type of intruder from the SO.

In the known methods of using PIKSO, it is recommended to install the CO at a height of 0.7-0.9 meters from the ground level [4-6]. Such a height of the installation of CO, the shape and dimensions of the SO of the CO can significantly reduce the sharp drop in the sensitivity of CO to the end of its SO. Thus, the drop in sensitivity to changes in thermal contrast, introduced by a person crossing the SA SO closer to its end, is reduced (compensated) by increasing the transverse dimensions of the SA SO. Its lower limit runs along the ground level (where the lower part of the human body, including the feet) is located, the upper limit is almost at the level of human growth (Fig. 1) [4-6]. Those. in the known methods, the height of the installation (0.7-0.9 meters) and the orientation of the axis of the ES parallel to the surface of the earth at a given threshold of operation provides the required probability of detection at the end of the ES [4-6].

The authors note that for the known method of recognizing the type of an intruder with an infrared detection tool, ensuring the maximum probability of detecting a human intruder at the end of the SO SS is not a priority, since the method is used for security monitoring of roads and it uses only the middle part of the SS SO [7].

The authors also note that the elongated rectangular shape of the profile between the wheel axles of most vehicles, regardless of the shape of their body, is at a height of up to 1 meter (Fig. 3).

It is proposed to provide a relatively uniform thermal contrast recorded by the CO between the front and rear wheelset, and thus reduce the probability of a recognition error, by orienting the SO of the CO over the road with the calculation of detecting the vehicle in a specific, conditionally allocated part of it 7: the lower limit is the threshold of the body, the upper limit is along the hood (Fig. 3).

The specified part of the majority of passenger cars (Fig. 2, 3) is close to an elongated rectangular and has a fairly uniform heating between the wheel axles, which eliminates a serious impact on an undesirable increase or decrease in the amplitude of the pulse when the car is in the EZ along the entire length of the body. The upper part of the vehicle profile, which is the most different from a rectangular shape, and therefore gives a different temperature contrast along the length from one wheel axle to another, is outside the boundaries of the SR, and therefore will not affect the signal generation result (Fig. 3, 6).

In order to ensure complete coverage of the SC SO with part 7 of the vehicle, which has the most uniform heating, it is necessary to install the SC at a height of 0.3 meters from the ground level and set the optical axis of the two-beam SC SC at a vertical angle at which the lower boundary of the two-beam SC SC would be parallel to the level land (Fig. 6). So, taking into account the removal of CO from the road section 5 by a distance H, the height to the upper boundary of the SO SO over the entire width of the road, which is about 8 meters, does not exceed the height of the part 7 of the vehicle, which completely covers the ZO SO in the vertical plane. In order for the lower boundary of the SO SO to be parallel to the ground level, it is necessary to orient its optical 3rd axis at a vertical angle V, which can be done using an optical sight with a vertical angular grid. This angle corresponds to half the viewing angle of the CO (α) vertically, which is indicated in the performance characteristics of each CO (Fig. 6).

where V is the vertical angle of orientation of the optical axis relative to the ground level, degrees;

α - vertical viewing angle of CO, degrees.

An analysis of the characteristics of SO used to protect terrain shows that the value of the vertical viewing angle is the same for most of the SO, its value lies within 3 degrees [4-6].

The method for determining the boundaries and dimensions of the area of the detection zone of the passive infrared detection means used to detect the intruder and recognizing its type includes two stages: preparatory and main.

Preparatory stage:

1. Installation of a detection means 1, including: an optical system 8, a pyro receiver 9, an amplifier 10, an alarm generator 11, a signal interface 12, a memory device 13, a device 14 deciding at a height of 0.3 meters from the ground level 2 at a distance H from section 5 of the road (Fig. 6, 8).

2. Orientation of the optical axis 3 to the section 5 of the road at a horizontal angle of 90 degrees, and to the ground level 2 at a vertical angle V, ensuring the passage of the lower boundary parallel to the ground level (Fig. 6).

3. Recording in the device 14 of the algorithm for determining the type of intruder.

4. Starting the detection tool 1 in standby mode.

The main stage begins when the intruder moves through the controlled section of the road and enters the zone of the detection means 1, it includes:

1. Formation of a useful signal by a pyro-receiver 9, amplification of the signal by an amplifier 10 and the signal received at the input of the alarm generator 11 (Fig. 8).

2. Formation of an alarm signal by the shaper 11 of alarm signals and recording by the device 13 of the memory of the pulses of the useful signal generated by the pyro receiver 9.

3. Determining by the decisive device 14 the number of local maxima or minima in the first pulse of the useful signal and making a decision about the type of intruder who crossed the DO:

- if the first pulse of the useful signal generated when the intruder crosses the DO has one local maximum or minimum, then the type of the intruder is a walking intruder;

- if the first pulse of the useful signal generated when the intruder 30 crosses has two local maxima or minima, then the type of the intruder is an intruder on a wheeled vehicle.

4. Transmission by the detection means 1 through the interface 12 of an alarm signal and information about the type of intruder to the system 15 for collecting and processing information (Fig. 8).

5. Reception by the system 15 of collecting and processing information from the interface 12 of the alarm signal and information on the type of intruder (Fig. 8).

6. Resetting the memory device 13 (Fig. 8).

The essence of the invention is illustrated by graphic materials, where it is presented on:

- fig. 1 is a diagram of the deployment of a two-beam passive infrared detection tool in a known method for recognizing the type of an intruder with an infrared detection tool (side view);

- fig. 2 - profile of a wheeled vehicle, having a shape close to an elongated rectangular between the wheel axles;

- fig. 3 shows the profile of a wheeled vehicle having a shape substantially different from an elongated rectangular one between the wheel axles;

- fig. 4 - the form of a useful signal from a car with two local maxima;

- fig. 5 - the form of a useful signal from a car without local maxima;

- fig. 6 is a diagram of the deployment of a two-beam passive infrared detection tool in the proposed method (side view);

- fig. 7 is a table for ensuring the required conditions for the minimum distance to the road and uniform thermal contrast between the wheel axles inside the detection zone, depending on the distance between the detector and the road;

- fig. 8 is a block diagram of the interconnection of the devices used in the implementation of the proposed method.

The technical result consists in obtaining the possibility of recognizing the type of intruder detected by a two-beam passive infrared detection means with a minimum recognition error, regardless of the shape of the vehicle profile.

Sources of information

1. Shumov, V.V. Application of mathematical methods and models to substantiate decisions on the protection of the state border: Scientific and practical guide. - Part 2. - M.: Enlightenment, 1996. - 196 p.

2. Gruba, I. Security alarm systems. Technical means of detection / I. Gruba. - M.: Solon-press, 2012. - 220 p.

3. Magauenov, R.G. Burglar alarm systems: fundamentals of theory and principles of construction: Uch. allowance / R.G. Magauenov - M.: Hot - Telecom, 2004. - 367 p.

4. RSK "Radiobarrier-MF". Operation manual PMEK.424242.9000RE - M .: "Polyus-ST", 2011. - 65 p.

5. Rapidly deployable complex "Radiy - DBK". Operating manual YUSDP.425149.001RE - Penza: "YUMIRS", 2013. - 41 p.

6. Mobile complex for the protection of the area "Mongoose". Operation manual STVF.425624.001 RE - Stavropol: "Steelsoft", 2017. - 52 p.

7. Pat. 2712648 Russian Federation, IPC 51 G08B 13/19 A method for recognizing the type of intruder by an infrared detection tool / S.A. Udot, I.D. Sable - No. 2019114471; dec. 08.05.19; publ. 01/30/20, Bull. No. 4.

Claims (1)

A method for determining the boundaries and dimensions of a section of the detection zone of a passive infrared detection tool used to detect and recognize the type of intruder, which consists in installing one passive infrared detection tool near the road at a distance of at least 40% of the maximum length of the two-beam detection zone so that its width in place the intersection with the road was at least 1 meter; orienting the passive infrared detection means so that the axis of its two-beam detection zone intersects the road section at an angle of 90 degrees; transition of the detection means to the alarm mode when the intruder crosses its two-beam detection zone; recording by means of detecting a useful signal during the entire time it is in the alarm mode; application in the detection tool of the algorithm for determining the type of intruder by the shape of the useful signal: the first pulse of the useful signal generated when the intruder crosses the detection zone has one local maximum or minimum - a walking intruder, the first pulse of the useful signal generated when the intruder crosses the detection zone has two local maximum or minimum - an intruder on a wheeled vehicle; transmission by the detection means of information about the type of intruder - a foot intruder or an intruder on a vehicle to the information collection and processing system; providing registration by the system for collecting and processing information of the alarm signal and information about the type of intruder from the detection tool, characterized in that the detection tool is installed at a height of 0.3 meters from the ground level; the optical axis of the two-beam detection zone of the detection tool is oriented at a vertical angle, at which the lower boundary of the two-beam detection zone of the detection tool is parallel to the ground level.

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