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SMART” SENSORS FOR INTELLIGENT SECURITY SYSTEMS..
UKOV Vyacheslav Sergeevich, Candidate of Technical Sciences
RYCHKOV Sergey Alekseevich
“SMART” SENSORS FOR INTELLIGENT SECURITY SYSTEMS
The article examines the status, possibilities of use and development prospects of modern alarm sensors used in intelligent security systems.
The main trends in the development of modern security systems (SS) are the processes of automation, integration and informatization based on artificial intelligence [1]. These trends are most fully manifested in the development of modern alarm sensors(DTS) for security systems. For greater clarity when conducting the analysis, Fig. 1 shows the diagrams of generalized systems of safety and life support (SLS) of an object and a person.
Fig. 1. Diagrams of generalized systems of safety and life support of a person and an object
Ensuring security and life support includes a wide range of activities aimed at protecting against various types of threats, the source of which (and the object of protection) can be three main parts: man, nature and the man-made environment (everything created by man).
It is known that when organizing a system of physical protection of an object, the classical principle of sequential boundaries is used, in case of violation of which threats will be promptly detected and their spread will be prevented by reliable barriers. Such boundaries (security zones) should be located sequentially, for example, from the fence around the territory of the facility to the main, especially important premises. The optimal location of security zones and the placement of effective technical means of protection (detection and counteraction) in them form the basis of the concept of physical protection of any facility.
As a rule, when organizing a system of physical protection of facilities, a three-line physical protection scheme is most often used (Fig. 2).
Fig. 2. Typical three-line scheme of physical protection of an object
As is known, the main link of the physical protection system is the detection subsystem (security alarm), consisting of sensors (detectors), means of transmitting notifications, control and monitoring devices and centralized monitoring consoles.
The most important component of the detection subsystem are alarm sensors, the characteristics of which determine the main parameters of the entire protection system. Since each line of defense performs its own tasks and has its own characteristics, further analysis of alarm sensors used in physical protection systems of objects is carried out taking into account these characteristics.
Alarm sensors for ensuring physical protection of objects
When designing a security system, one of the central tasks is to select the optimal means of notification and, first of all, alarm sensors. Currently, a large number of various alarm sensors have been developed and are used. Let us briefly consider the operating principles, distinctive features and methods of application of the most common of them.
The classification of modern alarm sensors for ensuring physical protection is presented in Fig. 3.
Fig. 3. Classification of modern alarm sensors
for ensuring physical protection of premises
Brief characteristics and features of using alarm sensors
Based on the analysis of the market of technical means of ensuring security, in particular, alarm sensors for physical protection systems of objects, their main capabilities and features of use in organizing a security system are given below (Table 1).
Table 1. Comparative characteristics of alarm sensors
| Name of sensors | Features and operating principle | Note |
| Perimeter tension sensors | Sensors of this type consist of several rows of stretched wire connected to mechanical switches. The slightest bend in the wire triggers the alarm. Barbed wire is usually used to install tension sensors. | The switches are installed on special stands, which are 60 cm apart. The wire is stretched with a force of up to 45 kg, the switch mechanism is triggered when the wire bends more than 2 mm. |
| Perimeter infraacoustic sensors | They are installed on metal fences and detect low-frequency sound vibrations of the fences during their overcoming | False alarms of such sensors are possible due to street noise from nearby roads |
| Perimeter electric field sensors
|
Sensors of this type consist of two parts: a transmitter and several receivers. Both parts of the sensor are made of electric cables stretched between the poles. | When an intruder passes between the transmitter and the receivers, a change in the electric field between them occurs, which is the alarm signal. |
| Perimeter vibration sensors | Sensors of this type are contact switches of various types, connected in series or parallel. The sensors are mounted on posts or fence mesh and are triggered by swings, shocks or vibrations. Such sensors are usually equipped with microprocessors for processing signals from contact switches, generating and sending an alarm command to the central security post. | Contact switches of vibration sensors according to the operating principle are mercury, ball, piezoelectric and pendulum |
| Perimeter electret sensors | They are made of coaxial cable with radially polarized dielectric. Such cable is pulled through the perimeter fences of the object. At the moment of overcoming the fence, the cable is shaken and, accordingly, the electric signal passing through the cable changes. Like vibration sensors, electret sensors are equipped with microprocessors to control the response threshold and can be adjusted to recognize impacts caused by wind, thrown stones or other objects, animals, birds, vibrations of the soil from moving vehicles, hail or snow, earthquakes, movement of tree branches. | Perimeter vibration and electret sensors can be bypassed by digging under or overcoming them from above without touching them. |
| Infrared space monitoring sensors | The principle of operation of the sensors is based on changing the signal from the emitter to the receiver when an intruder gets between them. Infrared LEDs or small laser installations are used as emitters. The distance between the emitter and the receiver is no more than 100 meters. Several such devices are usually installed on special poles to create a vertical detection strip of the required height | To increase reliability, frequency modulation of the radiation signal is sometimes used. Sensors may lose their functionality in thick fog and snowfall |
| Microwave sensors for space control | Consist of two parts: a super-high-frequency transmitter and receiver, which are installed at a distance of up to 150 meters from each other. In this space between them, an electromagnetic field is created, the change in which when an attempt to pass is registered by the receiver | For such sensors to work effectively, it is necessary that the height of the soil unevenness does not exceed 5 — 7 cm, and there is no vegetation in the coverage area. |
| Seismic sensors | There are two types of this type of sensor. The first type is liquid and consists of two hoses with liquid placed side by side in the soil. Such sensors are triggered by a change in pressure in one of the hoses when an intruder passes. The operating principle of the second type of sensor is based on the piezoelectric effect, in which the electrical signal changes when pressure is applied to the piezoelectric element. | Both types of seismic sensors are sensitive to extraneous vibrations caused, for example, by passing vehicles or strong winds. Seismic sensors are used to protect the perimeters of territories and buildings, they are installed covertly in the soil or its covering, under the surfaces of walls and building structures. |
| Magnetic sensors | They are made of wire mesh that is laid in the ground. Sensors of this type react to the passage of a person with a metal object of sufficiently large mass. The presence of metal causes induction changes in the electric field of the wire mesh, which triggers an alarm signal. | Magnetic sensors are ineffective near roads and railways. False alarms from lightning discharges, powerful electric motors and relays are possible. |
| Seismomagnetic sensors | They are made in the form of an electric cable laid in the soil. The electric signal changes under the influence of both seismic and magnetic disturbances, for example, when a person passes by and carries a weapon. | The reasons for false alarms are the same as in the case of magnetic sensors |
| Electromechanical switches | The operation of sensors of this type is based on recording the break in the electric circuit when an intruder acts. They are used to monitor the perimeters of buildings and premises. | Two types of sensors are manufactured: with non-destructive elements (like buttons) and with destructible contacts when using, for example, conductive glass or foil mesh. |
| Magnetic switches | Sensors of this type consist of a switch (the so-called reed switch), the contacts of which open or close under the influence of a magnet. | The sensor consists of two parts: a movable part and a fixed part. A magnet is installed on the movable part, such as a door or window frame, and a reed switch is installed on the fixed part, which, when the movable part opens, opens the electrical circuit and causes an alarm to appear. |
| Wire mesh | They are used to detect penetration into a room through walls, floors, ceilings, doors, windows and other structures. The protected surface is covered with a grid of electric wire with cell sizes of 10 — 15 cm. Mechanical destruction of the grid cells leads to a break in the conductors and, accordingly, to a break in the electrical circuit. | For camouflage, the sensor grid can be covered with wallpaper or facing materials |
| Perimeter ultrasonic sensors | The action is based on the registration of ultrasonic waves from an intruder when it impacts the elements of the building or room perimeter structures. Both passive and active ultrasonic sensors are used. Passive sensors register ultrasonic vibrations of air or another medium at frequencies of 18 — 60 kHz, which occur when attempting to destroy metal structures mechanically or thermally.There are two types of active ultrasonic sensors. The first uses elements of the perimeter structures of the protected premises. When such an impact occurs, such as breaking a window glass, the connection between the transmitter and receiver through the glass is disrupted and the sensor is triggered. Active ultrasonic sensors of the second type register a change in frequency (the signal emitted by the sensor) in the protected environment, for example, when opening a lock or sawing off a metal grate. | |
| Capacitive sensors | They are used to protect protective metal grids of utility lines. The operation of the sensors is based on recording changes in electrical capacity between the floor of the room and the internal grid fence. | |
| Ultrasonic sensors for monitoring rooms | Sensors of this type with emitting and receiving parts register changes in the radiation signal reflected from the intruder. For premises up to 50 sq. m., single-housing sensors can be used. Larger premises are protected by dual-housing sensors: the emitter, located in a separate housing, is mounted on one wall, and the receiver (or several receivers) are mounted on the opposite wall. The sensor operates based on the interference of ultrasonic vibrations and the Doppler effect. | Large objects located in the room limit the operation of such a sensor, creating shielding areas (“dead zones”) in which the sensor does not respond to the intruder's movement. |
| Microwave sensors | They operate in the microwave range at frequencies of about 10.5 GHz. Emission and reception are carried out by one antenna. The sensors detect movement indoors. Their operation is based on the interference of centimeter-range radio waves emitted by the sensor. They are very effective, but require careful adjustment. | Long-term exposure to sensor radiation is harmful to health |
| Photoelectric sensors | The unique capabilities of these sensors make them the only choice in many areas of science, industry and household appliances. In the field of security, they are actively used in physical protection systems for objects. Small size and weight, high sensitivity in a wide spectral range, the ability to analyze images at the hardware level — this is what modern photoelectric sensors on devices with charge coupling provide | These sensors, when building physical protection systems for objects, allow for full integration of security alarms with security television systems. |
| Photoswitches | The operation of this type of sensor is based on the interruption of a light beam of any range by an intruder, formed by an appropriate filter. | |
| Acoustic sensors | These sensors include a microphone and a signal processing unit. They are used to detect intruders and respond to sounds that inevitably occur when trying to enter a protected area. | |
| Barometric sensors
|
A very promising type of sensor, which has been actively used recently in security alarm systems. It is designed to protect closed spaces. The sensor responds to air pressure fluctuations in the protected area, is resistant to noise, vibration, movement of people and animals, does not have a harmful effect, is triggered when doors, windows, vents are opened or when walls, ceilings, doors and windows are destroyed. | Very economical (current consumption is no more than 1 mA) and does not have a harmful effect on people. |
| Biometric sensors
|
The operating principle of this type of sensors is based on the analysis of human biometric parameters. Biometric sensors (BS) can be either contact or contactless. According to the operating principle, BS are divided into static, dynamic and combined. The most commonly used bio-features are the shape of the face and hand, the pattern of the retina, finger skin, signature, iris, voice characteristics, gait, etc. According to the manufacturing technology, BS can be classified as television, thermal imaging, semiconductor, ultrasonic, pyroelectric, electro-optical, etc. | Biometric sensors are most often used to identify people, since they provide the highest level of identification |
| Combined sensors | Such sensors are a single design, in which two sensors of different types are located, for example, sound and infrared, and they work independently of each other. Combined in one housing, they allow to reduce the price compared to the case when two separate sensors are used | |
| Combined sensors | The most effective and universal at present are the so-called combined sensors, in which several physical phenomena are used simultaneously for greater efficiency, mutually complementing each other | By making the appropriate adjustments, it is possible to obtain a sensor with the required specific characteristics. For example, to obtain a given sensitivity with an acceptable probability of false alarm |
Physical principles of operation of modern sensors
The basic principles of operation of modern sensors and their features are given in Table 2.
Table 2. Basic principles of operation of modern sensors
| Effect or phenomenon | Transformation | Essence |
| Pyroelectric effect | Temperature – electricity | The appearance of electric charges on the faces of crystals with increasing temperature |
| Thermoelectric effect | Thermal energy – electrons | Electron emission when heating metal in a vacuum |
| Peltier electrothermal effect | Electricity – thermal energy | Absorption (generation) of thermal energy by electric current in a circuit with bimetallic connections |
| Thomson electrothermal effect | Temperature and electricity – thermal energy | Absorption (generation) of thermal energy at different temperatures of sections in a homogeneous circuit |
| Thermal conductivity | Thermal energy – change in physical properties | Heat transfer inside an object to an area with a lower temperature |
| Thermal radiation | Thermal energy – infrared rays | Optical radiation with an increase in the temperature of an object |
| Seebeck effect | Temperature – Electricity | Emergence of EMF in a circuit with bimetallic connections at different layer temperatures |
| Photovoltaic effect | Light – Electricity | Emergence of EMF in a p-n junction irradiated with light |
| Photoconductivity effect | Light – electrical resistance | Change in the electrical resistance of a semiconductor when irradiated with light |
| Zeeman effect | Light, magnetism – spectrum | Splitting of spectral lines when light passes through a magnetic field |
| Raman effect (combination scattering of light) | Light – light | The emergence in a substance of light radiation that differs in spectrum from the original monochromatic |
| The effectPockels | Light and electricity – light | Splitting of a light beam into ordinary and extraordinary when passing through a piezoelectric crystal with an electric voltage applied to it |
| The Kerr | Light and electricity – light | Splitting of a light beam into ordinary and extraordinary in an isotopic substance with an electric voltage applied to it |
| Faraday | Light and magnetism – light | Rotation of the plane of polarization of a light beam when passing through a paramagnetic substance |
| The Hall | Magnetism and electricity – electricity | The emergence of a potential difference on the faces of a solid when an electric current is passed through it and a magnetic field is applied |
| The Doppler | Sound, light – frequency | Change in frequency during mutual movement of objects |
| Magnetoresistance | Magnetism and electricity – electrical resistance | Increase in electrical resistance of a solid in a magnetic field |
| Magnetism – deformation | Deformation of a ferromagnetic body in a magnetic field | |
| Piezoelectric effect | Pressure – electricity | The emergence of a potential difference on the faces of a ferroelectric under pressure |
Analysis of the technical characteristics of modern sensors shows that as microprocessors were introduced, DTS became increasingly intelligent (with artificial intelligence) [2]. Currently, so-called dual technology sensors, i.e. combined sensors, have good intellectual capabilities. These capabilities can be illustrated by the example of the DS970 dual technology microprocessor security sensor from Detection Systems.
This sensor combines a passive infrared detector with a Fresnel lens and a microwave detector based on the Doppler effect. It has two types of directional diagram: standard (21×21 m) and “Beam” – 30×3 m. Good adaptability to various external conditions is achieved through independent sensitivity adjustment of each detector. An alarm signal is generated provided that the infrared and microwave detectors simultaneously register a violation in their security zone. In this case, the amplitude and time parameters of the signals for each detector must correspond to the alarm state. Then the signal from the IR detector is processed by the “Motion Analyzer” circuit, which checks the shape and time characteristics of the signal. The microprocessor automatically adjusts to the speed of movement and the amplitude of its signal. This analyzer does not give false alarms for disturbances caused by hot and cold air flows, the operation of heating devices and air conditioners, the impact of interference from sunlight, lightning and car headlights. “Motion Analyzer” provides two levels of IR detector sensitivity.
The microwave detector signal registration and processing circuit identifies and blocks sources of repeated false alarms and provides flexible adaptation to background disturbances. The algorithm used significantly reduces the probability of false alarms and maintains high reliability of registering a real violation of the security zone. In addition, this sensor also provides “protection from masking”, the “presence control” function, protection from opening and automatic self-testing of IR and MW detectors.
A characteristic trend of global technological development in the last decade has been the emergence of integrated, including microsystem technologies[3]. The initiating factor contributing to the dynamic development of microsystem technology was the emergence of so-called microelectromechanical systems — MEMS, in which galvanic connections are in close interaction with mechanical movements. A feature of MEMS is the fact that electrical and mechanical units are formed from a common base (for example, a silicon substrate), and, as a result of using the technology for forming volumetric structures, microsystem technology with high operational and technical characteristics (mass and dimensions, weight, energy, etc.) is obtained, which immediately attracted the attention of specialists — developers of special equipment.
The use of MEMS technologies in modern electronic systems allows for a significant increase in their functionality. Using technological processes that are almost identical to the production of silicon microcircuits, MEMS device developers create miniature mechanical structures that can interact with the environment and act as sensors that transmit the impact to the integrated electronic circuit. Sensors are the most common example of the use of MEMS technology: they are used in gyroscopes, accelerometers, pressure gauges, and other devices.
Almost all modern cars now use MEMS accelerometers to activate airbags. Microelectromechanical pressure sensors are widely used in the automotive and aviation industries. Gyroscopes are used in a variety of devices, from sophisticated spacecraft navigation equipment to joysticks for computer games. MEMS devices with microscopic mirrors are used to produce displays and optical switches.
Microswitches and resonant devices made using MEMS technology demonstrate lower ohmic losses and high quality factor with reduced power consumption and dimensions, better repeatability and a wider range of variable parameters. In biotechnology, the use of MEMS devices allows the creation of cheap but productive single-crystal devices for decoding DNA chains, developing new drugs and other special preparations (“laboratory on a chip”). In addition, it is also necessary to note the capacious market of inkjet printers, the cartridges of which use microfluidic MEMS devices that create and release microdroplets of ink under the control of electrical signals.
According to experts, the development of microsystem technology can have the same impact on scientific and technological progress as the emergence of microelectronics had on the formation and current state of the leading fields of science and technology. In the near future, we can expect the creation of microsystem sensors for devices for detecting various odors, which will certainly significantly activate forensics and will contribute to solving the problem of biometric contactless identification of a person and control of unauthorized access.
Examples of solving non-traditional problems using DTS
We will consider modern possibilities of solving non-traditional problems using DTS using examples of organizing hidden control of unauthorized access to premises.
Hidden control of unauthorized access to premises using an IR channel
Perhaps the simplest option for organizing hidden unauthorized access control (UAC) to a room is to use two portable personal computers (PPC). Any class of computer with a standard infrared port that meets the requirements of the Infared Data Association (IrDA) and provides wireless data transfer can be used as PPC. To solve this problem, PPCs are used in a closed state in an economical mode of operation from an internal battery. The only condition is a direct line of sight between the IR ports of the PPCs. If necessary, a household mirror can be used.
There are also other options for contactless control of unauthorized access using peripheral devices with a standard IR port. Special software can be developed by a trained user in a high-level language. If necessary, urgent automatic notification of the user indicating the time of unauthorized access is possible (SMS message via mobile phone (MT)). This option is implemented in wireless communication mode without a cable connection of the MT to the control panel. The MT is briefly switched on at the time of unauthorized access.
Hidden control of unauthorized access to the premises using a micro video camera
When solving this problem, the following main options are possible:
A household control panel with a built-in micro video camera (MVC) is used
In this case, the control panel in autonomous mode continuously films the location of possible unauthorized access (e.g. doors) and records it on the computer's hard drive. If urgent notification of unauthorized access is required, an image analysis program is used, which, when the image changes (unauthorized access appears), issues a command to send an SMS message about unauthorized access indicating the time of the violation.
A household control panel with an external micro video camera is used
In this case, any household control panel with a connected external micro video camera is used (an option with a WEB camera connected via a USB port to the control panel and wireless Internet access is possible).
Specific options for implementing hidden control of unauthorized access devices in a room using publicly available technical means, including various combinations of the options discussed above, are determined by the tasks to be solved, capabilities, and specific operational environment.
A combined sensor “Micro-Foto” is used
A logical conclusion about the need to integrate IR sensors with a video camera to detect unauthorized access devices in a controlled object is realized today in the “Micro-Foto” equipment. With its use, it is possible to ensure:
- effective camouflage that does not attract attention — in the form of a standard security alarm sensor;
- 24-hour video monitoring of objects;
- covert photography with automatic activation by signals from built-in motion sensors, IR and video detectors;
- accumulation of up to 20,000 photo frames on a removable miniature Flash card;
- input of footage from the card into a PC via a standard port;
- viewing photo frames on a computer, editing and archiving them;
- programming of shooting parameters, including setting the quality of frames, adaptation to the illumination of the object by contrast and brightness, setting the number of frames taken when detectors are triggered, etc.;
- code access using an IR remote control.
Filming is performed automatically by a hidden micro video camera on commands from IR and video detectors. The user of the equipment only needs to install the bracket on which the “Micro-Foto” equipment is located in the form of a standard security sensor, and connect the adapter to the network. To view and analyze photo frames, it is necessary to remove the Flash card from the “Micro-Foto” product and download the footage to the computer.
Trends and prospects for the development of alarm sensors
Based on the results of the conducted research, we can briefly conclude that modern alarm sensors are characterized by the following main development trends:
- integration of different operating principles (for example, dual technology: infrared and microwave in one housing);
- integration of sensors with communication equipment;
- microsystem integration;
- use of computer (microprocessor) processing;
- the presence of artificial intelligence;
- decentralization, self-testing and autonomous operation.
Perhaps the most revolutionary changes in the operational and technical characteristics of sensors occurred after the introduction of microprocessor signal processing (MPS) [2], which made it possible to ensure all the above-mentioned development trends in the future. This conclusion can be confirmed by the example of modern glass break sensors, which use a microprocessor signal analyzer that recognizes the characteristic spectral components that occur when glass breaks.
In particular, the DS1100 series sensors from Detection Systems use a microprocessor signal analyzer that monitors the analog signal over a wide frequency spectrum. The alarm is triggered only if the spectral components of the signal and their time dynamics of change correspond to the set of reference data. In this case, the probability of a false alarm is reduced and reliable operation of the sensor in difficult conditions is guaranteed. These sensors are designed to protect simple, tempered and reinforced glass, as well as glass with a film coating. The test mode allows you to check the level of external noise, carry out separate control of the level of infra-low and high-frequency noise and determine the optimal location of the sensor even in difficult conditions.
Considering the prospects for the development of DTS, one cannot help but dwell on effective thin-film magnetoresistive sensors, which use the magnetoresistive effect, i.e. a change in the electrical resistance of the material under the influence of an external magnetic field. The main elements of the sensor structure are two ferromagnetic layers made of Co, Ni, Fe alloys and separated by a layer of non-magnetic metal — Cu, Ag, Au, etc. FeMn, FeIr, NiO films are usually used as a fixing layer that creates an exchange interaction with the nearest ferromagnetic layer for its fixation.
Among the areas of application of magnetoresistive sensors, one can note devices for measuring the intensity of constant and alternating magnetic fields (magnetometers), navigation devices (electronic compasses), current meters, galvanic isolation devices, angular and linear position sensors, rulers (matrices) of sensors for diagnostics of printed circuit boards and products made of ferromagnetic materials, sensors for cars (tachometers), combined playback heads for magnetic disks and tapes, security systems.
Perhaps the greatest influence on the development of magnetoresistive sensors in recent years has been exerted by photoelectric devicescharge-transfer devices (CTS). In these solid-state devices, charge packets are transferred to the output device due to the movement of the position of potential wells. The threshold sensitivity of the CTS corresponds to the perception of the image of an object in starlight. Currently, CTS are the main element base in the following areas:
- household television systems (VHS, SVHS, HDTV, etc.);
- specialized television systems: security, medicine, motion picture analysis, scientific research, transport;
- robot vision;
- devices for inputting images into computers;
- digital cameras;
- non-contact measuring devices;
- ground-based and space astronomy;
- remote sensing of the Earth from space;
- security systems.
One of the directions of further development of DTS is the search for fundamentally new approaches to the creation of modern sensors. As an example, let us consider the implementation of a device for protection against unauthorized access (UAA) of a person to a controlled area based on torsion interactions. This device was developed at Penza State University (PSU).
Currently, various sensors for detecting object movement are used to protect against unauthorized access, including those based on the Doppler effect. The main disadvantage of such sensors is the possibility of failure if the speed of movement falls below the limit. Therefore, a very urgent problem is the search for new principles for detecting slow and very slow (up to a centimeter per hour) human movements in a controlled sector at a distance of several meters. The developers from PSU used the fact that a person is a biological object with a complex biofield, which includes an energy-information component, so a person can be considered as a source of a complex torsion field.
In the theory of energy-information interaction, the effect of changing the clock rate under the influence of an external torsion field is known. Therefore, a time sensor with an electronic master oscillator was taken as the basis for a sensor that responds to changes in the torsion environment in a room when a person appears. During the experiments, a research methodology was also developed that made it possible to single out the torsion effect among others. For three years, work was carried out to create elements sensitive to the effect of torsion fields and to identify their effect on the sensitivity and spatial selectivity of the sensor.
The developed torsion field sensor was subjected to thorough experimental studies, as a result of which it was established:
- the electronic time sensor, placed in a multilayer grounded electromagnetic screen-housing, responds to human movements relative to the sensor at a distance of several meters;
- the observed value of the sensor's response to human movements, expressed as a relative change in the period or frequency of the master oscillator, can be used in various practical applications;
- various circuit and design solutions make it possible to obtain the property of spatial directionality of the sensor, as well as to increase its sensitivity.
The practical results obtained in creating a torsion field sensor are very promising and are of undoubted interest to developers of not only means of protection against harmful fields, but also means of monitoring unauthorized access to various objects.
Thus, alarm sensors, which are a mandatory link in any modern security system, determine the main operational and technical characteristics of the SB, are developing dynamically and have good prospects for further development.
Conclusions
An analysis of the status and development trends of alarm sensors for protection against unauthorized access to controlled premises showed the following.
- Currently, alarm sensors are the most dynamically developing components of physical protection systems for facilities.
- The best characteristics of all existing alarm sensors are those with dual and triple technology.
- Microsystem and torsion sensors are very promising for solving non-traditional problems of physical protection of premises, in particular, for biometric contactless identification.
- The main directions of further development of DTS are integration, microprocessor processing, artificial intelligence, self-testing, decentralization, implementation of new physical phenomena and processes.
- The use of DTS is very effective in solving non-traditional problems of physical protection of premises.
- New microelectronic technologies significantly affect the composition and performance characteristics of modern DTS, in particular, the use of solid-state photoelectric sensors with charge coupling allows for optimal integration of the security television system into the physical protection system of an object.
Literature
1. Ukov V.S., Rychkov S.A. New technologies of intelligent objects: comfort plus safety./Special equipment, 2004, No. 4.
2. Sensors and micro-computers: Trans. from Japanese. L.: Energoatomizdat, 1986.
3. Ukov V.S. Microsystem special equipment./Special equipment, 2003, No. 4.