RU2545466C2 - Method of providing given level of magnitude of hypogeomagnetic field induction vector in cylindrical screening chamber and apparatus therefor - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: by turning a screening chamber by an angle which is proportional to a first difference signal, obtained by comparing a given level of the magnitude of the hypogeomagnetic field induction vector with a current value of the magnitude of the hypogeomagnetic field induction vector, measured inside the screening chamber, the current value of the magnitude of the hypogeomagnetic field induction vector is varied until a given level is established, after which the current value of the magnitude of the hypogeomagnetic field induction vector is maintained at the given level by turning the screening chamber by an angle which is proportional to a second difference signal, obtained by comparing the average value of the magnitude of the geomagnetic field induction vector at a given geographic point with the current value of the magnitude of the induction vector of an external magnetic field, measured outside the cylindrical screening chamber.

EFFECT: monitoring the effect of the Earth's magnetic field on an object, fluctuation of the magnetic field due to cosmic action, changes in the magnetic field within the camera when its position changes relative to the magnitude of the induction vector of an external magnetic field.

3 cl, 4 dwg, 1 tbl

Description

The invention relates to techniques for magnetic and electromagnetic shielding during biological, biophysical and biomedical research in the field of studying the influence of magnetic fields on biological and biophysical objects. The intensive use of electromagnetic and electric energy in the modern information society has led to the emergence of a new significant environmental pollution factor - electromagnetic (Grigoryev OA, Bicheldey EP, Merkulov A.V. et al. Definition of approaches to standardizing exposure anthropogenic electromagnetic field on natural ecosystems. Reference publication. Russian National Committee for Protection against Nonionizing Radiation, 1999). Its appearance was led by the development of modern technologies for the transfer of information and energy, remote control and monitoring, some types of transport, as well as the development of a number of technological processes. Currently, the world community has recognized that the electromagnetic field (EMF) of artificial origin is a significant environmental factor with high biological activity. A special concept has been introduced - electromagnetic ecology.

Compared to naturally occurring electromagnetic fields (Earth’s natural electromagnetic background), man-made electromagnetic fields have orders of magnitude greater intensity and uneven localization in space (Bingi V.N., Savin A.V. Physical problems of the action of weak magnetic fields on biological systems // Successes in Physical Sciences , 2003, volume 173, No. 3, pp. 265-300. Ptitsyna NG, J. Villorezi, LI Dorman et al. Natural and man-made magnetic fields as factors potentially hazardous to health // Successes in Physical Sciences , 1998, Volume 168, No. 7, pp. 768-790). The biological effect of artificial EMFs under long-term exposure accumulates, as a result of which the development of degenerative processes of the central nervous system, blood cancer (leukemia), brain tumor, hormonal diseases is possible. The most sensitive systems of the human body: cardiovascular, nervous, immune, endocrine and sexual.

The study of the influence of electromagnetic fields on biological objects is characterized by the presence of a large amount of experimental material confirming the very fact of such an effect and the almost complete absence of data on the possible mechanisms of these interactions.

Clarification of the mechanisms of the influence of electromagnetic fields on biological objects is an extremely urgent task, the solution of which may allow in the future to protect human life and health. For the correct formulation of such studies, it is necessary to significantly reduce the effect of all existing electromagnetic fields (including the natural electromagnetic background of the Earth) in a limited volume sufficient to accommodate a biological or biophysical object and conduct a specific experiment.

In research practice, shielding magnetic materials and shielding chambers (boxes) made of them, which have various shielding characteristics, are widely used. Recently, new soft magnetic materials based on cobalt have appeared, the so-called amorphous metal alloys (AMS), the tapes of which have been used to create shielding chambers (Gudoshnikov S.A., Venediktov S.N., Grebenshchikov Yu.B. Shielding camera for weakening the Earth’s magnetic field on the basis of rolled magnetic materials // Measuring Technique No. 3, 2012, pp. 56-61), which have record-breaking parameters in terms of obtaining magnetic field attenuation coefficients: 300 or more.

However, biophysical tasks are becoming more complicated. It is known that the geomagnetic field is subject to fluctuations (disturbances), the nature of which are flares on the Sun, interplanetary wind, phases of the Moon, as well as factors of anthropogenic nature.

Their influence on the results of experiments in shielding chambers can be detrimental to the object of study, despite the fact that it, of course, is reduced due to the shielding properties of the camera. In this regard, the researchers set the task of ensuring the constancy of the magnitude of the induction module of the hypogeomagnetic field during the experiment with possible external magnetic disturbances.

Traditionally, the measurement of the induction module of the hypogeomagnetic field in closed volumes (chambers, boxes) is carried out, for which standard magnetometers with one measuring probe, for example a flux probe, are used. First, the module of the induction vector of the field is measured outside the volume, and then inside and the magnitude of the module of the induction vector of the hypogeomagnetic field is monitored during the entire time the magnetic field effect on biological objects is studied.

An example of such a task is the technology of obtaining funds having heliogeomagnetoprotective properties according to the patent of the Russian Federation No. 2342149, MKI A61K 33/00, publ. December 27, 2008. The specified tool is exposed to a long exposure (at least 5 hours) in the working space of the shielding device, which attenuates the complete vector of the geomagnetic field by at least 300 times in comparison with the background. The exposure time of at least 5 hours does not allow the measurement and control of the attenuation coefficient of the geomagnetic field in the traditional (time-divided) way, it does not allow to take into account the influence of perturbations of the geomagnetic field.

In most known devices for protecting internal volumes from magnetic fields, the main emphasis is on the improvement of structural materials. Traditionally, materials in the form of steel, copper, aluminum sheets, and foil are used to create an electromagnetic screen or shielded volume (“Portable shielded camera” (RF patent No. 2345512, MKI H05K 9/00, published on January 27, 2009); “Shielded box with protected from external electromagnetic effects by internal volume "(RF patent No. 2402892, MKI H05K 9/00, publ. 10/27/2010)).

However, the task of protecting internal volumes from exposure to magnetic fields cannot be solved only in terms of improving the structural materials of the shielding chambers.

A device is known for studying the influence of electromagnetic fields on biological objects (RF patent No. 2454675, MKI G01R 1/00, 5/00, publ. 27.06.2012), containing a spherical magnetic screen. The screen made according to the invention provides shielding with constant and variable components of the magnetic field.

The disadvantage of this device is that it does not solve the problem of measuring the influence of an external magnetic field on objects inside the sphere. In addition, to access the object under study, placed inside a spherical screen, it is necessary to ensure its detachability, which is an intractable technological task. At the same time, ensuring high screening parameters of the screen is problematic.

A device is known for measuring the intensity and direction of external magnetic fields including power supply and recording units having respective semiconductor devices, US Patent 4218652, August 19 , 1980). This device is designed to measure only the external magnetic field.

A known method of determining the optimal parameters of the magnetic field to control seed germination (RF patent No. 2342658, G01N 33/487, G01N 27/74, A01C 1/00, publ. 12/27/2008), in which the studied object is subjected to simultaneous exposure to a magnetic field with a frequency 3-300 Hz, with a strength of 0.15-10 A / m and an alternating electric field with a frequency of 1-30 Hz and with a strength of 0.01-0.07 mV / m.

It is known "Device for stabilizing the geomagnetic field in the working volume" (RF patent No. 2274870, MKI G01R 33/02, publ. 04/20/2006) to protect biological and physical objects from magnetic influences. The device is based on a three-component flux-gate rod magnetometer, and the working volume is the same for the placement of the object of influence and the magnetometer.

The disadvantage of this device is that only the magnetic field from the internal source acts on the studied objects, but the influence of an external magnetic field is not taken into account.

GOST R 51724-2001 “Screened objects, premises, technical means. The field is hypogeomagnetic. Methods of measurement and assessment of compliance of field levels with technical requirements and hygienic standards ”regulates methods for measuring magnetic fields, and also recommends serial magnetometers for this purpose. Taking into account the requirements and regulations of GOST, modern devices are created and tools for determining the levels of the magnetic field inside the premises are developed, depending on the external sources of the electromagnetic field. The measurement of the magnetic field induction is carried out at control points in standard climatic, mechanical and electromagnetic operating conditions of controlled objects and the workplace (see paragraphs 6.2, 6.7, 7.5, B1). However, GOST does not consider the problem of stabilizing the module of the induction vector of the hypogeomagnetic field in the shielding chamber.

The well-known “Shielded box with internal volume protected from external electromagnetic influences” (RF patent No. 2402892, IPC H05K 9/00, published October 27, 2010), in which the obtained values of the degree of attenuation of the external electromagnetic field are achieved by the materials of the box walls. The measurements of the external magnetic field and the magnetic field inside the box are carried out using magnetometers.

The disadvantage of this solution is that when determining the protective properties of a box from exposure to a magnetic field, factors such as the effect of the Earth’s magnetic field on the object, magnetic field fluctuations from cosmic effects, a change in the magnetic field inside the box due to a change in the position of the box relative to the vector module induction of an external magnetic field, as well as the need to stabilize the magnetic field at a certain (predetermined) level when changing the position of the box relative to the external magnetic field.

However, despite the above disadvantages, RF patent No. 2402892 was adopted as a prototype for the method and device for stabilizing the module of the induction vector of the hypogeomagnetic field in the shielding chamber according to a partial similarity of technical solutions.

The objective of the present invention is to control the effect on the object of the Earth’s magnetic field, fluctuations of the magnetic field from cosmic effects, changes in the magnetic field inside the camera when the camera’s position changes relative to the external magnetic field induction vector module by providing a given level of the hypogeomagnetic field induction vector module in the cylindrical screening chamber, which can be installed in a wide range within its design characteristics and maintained constant.

The present invention is also the development of a device to provide a given level of the module of the induction vector of the hypogeomagnetic field in the shielding cylindrical chamber, which can be installed in a wide range within its design characteristics and keep constant.

The problem is solved in that in the method of providing a given level of the module of the induction vector of the hypogeomagnetic field in the shielding cylindrical chamber, it is proposed by rotating the shielding cylindrical chamber by an angle proportional to the first difference signal obtained by comparing the specified level of the module of the induction vector of the hypogeomagnetic field with the current value of the module of the induction vector of the hypogeomagnetic field field measured inside the shielding cylindrical chamber in real time, change the current value of m modulating the hypogeomagnetic field induction vector until a specified level is established, and then maintaining the current module value of the hypogeomagnetic field induction vector at a given level by rotating the screening cylindrical chamber by an angle proportional to the second difference signal obtained by comparing the average statistical value of the geomagnetic field induction vector module in a given geographical point with the current value of the modulus of the induction vector of the external magnetic field, measured outside the shielding ilindricheskoy camera in real time.

The problem is also solved by the fact that the device for providing a given module of the induction vector of the hypogeomagnetic field in the shielding cylindrical chamber according to the invention comprises a first flux-probe three-component magnetometer of the hypogeomagnetic field with a sensor installed inside the shielding chamber and a second flux-probe three-component magnetometer of the geomagnetic field with a sensor mounted behind outside the shielding chamber, while the shielding chamber is mounted with the possibility of rotation with the first and second servomotors, which alternately provide rotation of the shielding chamber, while the control input of the first servomotor is connected to the control output of the system for setting the level of the module of the induction vector of the hypogeomagnetic field connected by the information input to the information output of the first magnetometer and the control input to the first output of the control unit, and the control input of the second servomotor is connected to the control output of the automatic control system connected to the information input m second data output and a control input magnetometer - the second output of the control unit.

Moreover, the system for setting the level of the module of the induction vector of the hypogeomagnetic field can contain an input unit for the technological process program, the first digital multiplexer, a code comparison circuit, the first digital-to-analog converter and the first driver, the system for automatically regulating and stabilizing the set level of the module of the induction vector of the hypogeomagnetic field can contain an average value input unit geomagnetic field intensity vector module, second digital multiplexer, digital discriminator, Torah analog converter, an integrating amplifier and a second driver, and the control unit may include a synchronization unit coupled input to an output of the timer. In this case, the first magnetometer is connected by the information output to the first information input of the first multiplexer, and the second magnetometer is connected by its information output to the first information input of the second multiplexer, the technological program input unit is connected by the output to the second information input of the first multiplexer, the output of the latter is connected to the input of the code comparison circuit, the “equal” output of which is connected to the “stop” input of the first driver and the inverter input, the output of which is connected to the “stop” input of the second driver RA, the analog control input of the first driver is connected to the output of the first digital-to-analog converter, the input of which is connected to the control output “more-less” of the code comparison circuit, the first driver is connected with the output of the first servomotor mechanically connected to the rotary table drive of the shielding camera, while the input unit of the average value of the module of the induction vector of the geomagnetic field is connected with its output to the second information input of the second multiplexer, the output of which, in its the series is connected to the information input of the digital discriminator, the output of the latter is connected to the input of the second digital-to-analog converter, the output of which is connected to the input of the integrating amplifier, connected by the output to the control input of the second driver, connected by the output to the input of the second servomotor, the output of which is mechanically connected to the shielding rotary table drive cameras, the synchronizing device with its first output, which is the first output of the control unit, is connected to the control inputs of the unit the input of the technological program, the first digital multiplexer and the code comparison circuit, and is connected to the control inputs of the input unit of the average statistical value of the geomagnetic field induction vector module, the second multiplexer, and the digital discriminator with its second output, which is the second output of the control unit.

The invention is illustrated by drawings:

в системе координат, связанной с магнитным меридианом (ось X) и вертикалью (Z).Figure 1. Geomagnetic field induction vector $${\overrightarrow{B}}_0$$

in the coordinate system associated with the magnetic meridian (X axis) and vertical (Z).

Figure 2. The dependence of the magnitude of the induction vector of the hypogeomagnetic field in the center of the shielding chamber on the rotation angle α.

Figure 3. The dependence of the magnitude of the induction vector of the hypogeomagnetic field at the edges of the working volume of the shielding chamber on the rotation angle α.

Figure 4. A block diagram of a device for providing a given level of the module of the induction vector of a hypogeomagnetic field in a cylindrical screening chamber.

The way to ensure a given level of the module of the induction vector of the hypogeomagnetic field in the shielding cylindrical chamber is as follows. The average statistical value of the module of induction of the geomagnetic field at a given geographical point is compared with the current values of the module of the vector of the induction of an external magnetic field in real time to obtain a difference signal, and the values of the module of the induction vector of the hypogeomagnetic field and the attenuation coefficient of the geomagnetic field are determined. By turning the shielding cylindrical chamber, the module of the induction vector of the hypogeomagnetic field is changed to a predetermined level, its value is stabilized at a predetermined level. Depending on the technological process, by additional turns of the camera to specified levels, the next module values of the induction vector of the hypogeomagnetic field are established, automatically stabilized and maintained. The difference signal between the average value of the module of the vector of the induction of the geomagnetic field at a given geographical point and the value of the module of the vector of the induction of the external magnetic field, measured in real time, is used as the control in the system of automatic regulation and stabilization of the hypogeomagnetic field.

The value of the module of the induction vector of the hypogeomagnetic field of the hypogeomagnetic field is monitored in a cylindrical shielding chamber, in the initial position, set arbitrarily on the azimuth-adjusted lodgements of the turntable.

The chamber is pre-aligned by means of, for example, compasses relative to the direction of the induction vector of the external geomagnetic field.

The module of the induction vector of the hypogeomagnetic field is measured by means of a sensor, a measuring probe of a magnetometer, introduced into the working volume of the chamber.

The module of the external magnetic field induction vector is measured by a second magnetometer, the obtained value is compared with the value of the external magnetic field induction vector module, which is an average result of many days of monitoring the magnetic field at a given geographical point (average statistical value of the module), previously stored in memory.

Depending on the technological process, the next values of the module of the induction vector of the hypogeomagnetic field are established, automatically stabilized and maintained.

By comparing the average statistical value of the module of the vector of the induction of the geomagnetic field at a given geographical point with the values of the module of the vector of the induction of the external magnetic field in real time, a difference signal is extracted between the measured value of the module of the induction vector of the hypogeomagnetic field and the required value of this module recorded in memory - the set level. The difference signal is used as the control signal in the system of automatic regulation and stabilization of the hypogeomagnetic field. In this case, the control action is to rotate the camera to the required angle between its longitudinal axis and the magnetic meridian, and the attenuation coefficient of the magnetic field is a variable parameter.

The stability of a given level is affected by magnetic storms (mainly, as a result of solar activity). Therefore, the average statistical module value of the induction vector of the external magnetic field is taken as a reference value and compared with the value of the module of the vector of the external magnetic field induction in real time (using an external magnetometer), the set level is automatically monitored and maintained by the automatic control system. The difference signal is used as the control signal in the automatic control and stabilization system so that the readings of the internal magnetometer are constant and correspond to a given level.

Consider the efficiency of the proposed method on the example of the current technological installation used in biophysical research.

For the selected configuration of the shielding chamber using the AMC 82KZKhSR tape, the transverse and longitudinal attenuation coefficients of the geomagnetic field K _g⊥ and K _{g ||} respectively.

. Минимум модуля индукции гипогеомагнитного поля достигается, когда ось экрана Р перпендикулярна направлению вектора $${\overrightarrow{B}}_0$$

.It was determined that the attenuation coefficient of the geomagnetic field depends on the orientation of the longitudinal axis of the screen P relative to the vector of the geomagnetic field $${\overrightarrow{B}}_0$$

. The minimum modulus of induction of the hypogeomagnetic field is achieved when the axis of the screen P is perpendicular to the direction of the vector $${\overrightarrow{B}}_0$$

.

We show how the field inside the shielding chamber changes when its axis P is in the horizontal plane and the shielding chamber rotates around the vertical axis.

The elements of the geomagnetic field induction vector according to the Klyuchi magnetic observatory (10 km from Akademgorodok, Novosibirsk) are shown in Fig. 1. The X axis is directed along the magnetic meridian, the Z axis is vertical. According to the magnetic observatory, the average statistical value of the module of the geomagnetic field induction vector is 60600 nT (the result of many years of monitoring), and the inclination angle I of the geomagnetic field intensity vector relative to the X axis is 73.4 °. The rotation angle of the shielding chamber α is the angle between the longitudinal axis of the shielding chamber P and the Y axis. In the initial state, P is aligned with the Y axis, i.e. α = 0.

, $$\overrightarrow{j}$$

, $$\overrightarrow{k}$$

единичные векторы вдоль осей X, Y, Z соответственно. Найдем компоненты вектора $${\overrightarrow{B}}_0$$

в указанной системе координат.Let be $$\overrightarrow{i}$$

, $$\overrightarrow{j}$$

, $$\overrightarrow{k}$$

unit vectors along the axes X, Y, Z, respectively. Find the components of the vector $${\overrightarrow{B}}_0$$

in the specified coordinate system.

According to figure 2 you can write:

B _X = B ₀ cosI

B _Y = 0

B _{Z ′} = B ₀ sinI

. $${\overrightarrow{B}}_0={\mathrm{<figure-callout\; id="0"\; label="B"\; filenames="00000019.png,00000020.png"\; state="\{\{state\}\}">B</figure-callout>}}_0\cos I\cdot \overrightarrow{i}+{\mathrm{<figure-callout\; id="0"\; label="B"\; filenames="00000019.png,00000020.png"\; state="\{\{state\}\}">B</figure-callout>}}_0\sin I\cdot \overrightarrow{k}$$

.

, направленным вдоль продольной оси, тогдаThe position of the axis P of the screen is set by a unit vector $$\overrightarrow{P}$$

directed along the longitudinal axis, then

α is the angle between the axis of the screen P and the axis Y.

The induction of the field parallel to the axis of the screen is:

, то индукция поля, перпендикулярного оси $$\overrightarrow{P}$$

, находится из соотношения:As $${\mathrm{<figure-callout\; id="0"\; label="B"\; filenames="00000019.png,00000020.png"\; state="\{\{state\}\}">B</figure-callout>}}_0^2=B_{||}^2+B_{\perp }^2$$

, then the induction of the field perpendicular to the axis $$\overrightarrow{P}$$

is found from the ratio:

Thus, B _|| and B _{⊥ are} determined depending on the magnetic inclination I and the angle α of rotation of the axis of the shielding chamber.

In the General case, the induction of the field inside the shielding chamber is determined by the formula:

Using relations 2, 3, and 4, we obtain for the field induction module inside the chamber:

In our case, I = 73.4 °, then cos ² I = 0.0816 and to calculate the dependence (5), you can use the formula:

Values of K _{g ||} and K _{g⊥ are} determined when calculating the effective shielding chamber to attenuate the geomagnetic field, the walls of which are made of tape АМС 82КЗХСР. In the center of the screen they are equal: To _{r ||} = 99.3; K _r = 436.1. At the edges of the working volume: K _{g ||} = 48.6; K _g⊥ = 377.4.

Using these values, K _{g ||} and К _г⊥ , it is possible to calculate by the formula (6) the value of the magnetic field induction module В _Э in the center of the shielding chamber and at the edges of its working volume depending on the angle α. The results of this calculation are shown in Table 1 and in Figures 2 and 3 are graphs in dependence on the angle α _E at the center and at the edges of the working volume of the shielding chamber.

The calculation results presented in the table, performed on the example of an active shielding camera at a specific geographical point in certain geomagnetic conditions, clearly show the prospects of the proposed method for stabilizing the module of the induction vector of the hypogeomagnetic field by controlling the attenuation coefficient of the geomagnetic field during biophysical experiments and in the corresponding technological processes.

Table α (degree) _E (nTl) (Center) In _E (nTl) (Edge of the slave. Volume) 0 (180) 138.9 160.6 10 (190) 142.2 171.9 20 (200) 150.5 200.9 30 (210) 162.8 238.7 40 (220) 176.6 278.1 50 (230) 190.2 314.6 60 (240) 202.2 345.5 70 (250) 211.4 368.8 80 (260) 217.3 383.1 90 (270) 219.2 387.9 100 (280) 217.3 383.1 110 (290) 211.4 368.8 120 (300) 202.2 345.5 130 (310) 190.2 314.6 140 (320) 176.6 278.1 150 (330) 162.8 238.7 160 (340) 150.5 200.9 170 (350) 142.2 171.9 180 (360) 138.9 160.6

The figure 4 shows a device for providing a given level of the module of the vector of induction of the hypogeomagnetic field in a shielding cylindrical chamber that implements the proposed method. The device comprises a shielding cylindrical chamber 1, located on a rotary table 2, which is shown schematically (electromechanical couplings are not shown conventionally), the first digital fluxgate magnetometer 3 of a hypogeomagnetic field, the first three-component fluxgate magnetic field sensor 4, the first digital multiplexer 5, and the second digital fluxgate magnetometer 6 geomagnetic field, the second three-component flux-gate sensor 7 of the magnetic field, the second digital multiplexer 8, circuit 9 comparison of codes with operational memory Yu, first driver 10, inverter (NOT) 11, second driver 12, first digital-to-analog converter 13, first servo motor 14. Unit 15 for inputting the average value of the geomagnetic field induction vector module, digital discriminator 16 with random access memory, second digital-to-analog converter 17, integrating amplifier 18, a second servomotor 19, a synchronizing device 20, a timer 21, and a process program input unit 22. Moreover, the process program input block 22, the first digital multiplexer 5, the code comparison circuit 9, the first digital-to-analog converter 13 and the first driver 10 form a system for setting the level of the module of the induction vector of the hypogeomagnetic field (not shown in the figures), connected by an information input to the information output of the first magnetometer 3 and a control input - with the first output of the control unit (not shown in the figures), which is the first output of the synchronizing device 20. In turn, the unit 15 input srednestat the true value of the module of the geomagnetic field vector, the second digital multiplexer 8, the digital discriminator 16, the second digital-to-analog converter 17, the integrating amplifier 18 and the second driver 12 form a system of automatic regulation and stabilization of a given level of the module of the induction vector of the hypogeomagnetic field (not shown in the figures), connected information input with the information output of the second magnetometer 3 and the control input with the second output of the control unit, which is the second output synchronizing device 20.

The following are the purpose of the elements of the device and their brief description (figure 4).

The shielding cylindrical chamber 1 of finite length is made in the form of a multi-shell structure, on each shell of which a ribbon of cobalt-based amorphous metal alloy (AMS) is applied, having a coefficient of attenuation of the geomagnetic field strength vector module of at least 600, provided that the longitudinal axis of the chamber is oriented in azimuth the plane perpendicular to the direction of the geomagnetic field vector.

A cylindrical shielding chamber 1 is mounted on the rotary table 2. The first three-component flux-probe magnetic field sensor 4 is placed in the working area of the chamber 1, recording the orthogonal components of the magnetic field induction vector. The hypogeomagnetic field is measured by the first standard 3 digital fluxgate magnetometer having a sensitivity of no worse than 1 nT, the limit of the admissible value of the main relative error is no worse than 1% with a standardized data output / input port.

The rotary table 2 has a drive in the form of the first and second servomotors 14, 19 with the first and second drivers 10, 12. The first servomotor 14 is designed to align the shielding chamber 1 in the azimuthal plane in accordance with the program of the experiment (technological process). The second servomotor 19 is the actuating element of the automatic control system, which rotates the shielding chamber 1 in the azimuthal plane, compensating for the perturbation of the geomagnetic field so that the modulus of the induction vector of the hypogeomagnetic field is constant and equal to a predetermined value within the error. As motors, stepper motors of the type AD-200-32 are used.

Inverter 11 controls the first and second drivers 10, 12 at the “stop” inputs, while one driver is always in the active state, and the other in the passive state.

The input unit 15 of the average statistical value of the module of the geomagnetic field induction vector is intended for input through the second multiplexer 8 into the digital memory of the discriminator 16 of the above value based on the results of many years of monitoring the state of the geomagnetic field by the international system INTERMAGNET (Geomagnetic Observatory "Keys", Novosibirsk participates in the operation of this system ) or according to the results of our own observations at a given geographical point.

The synchronizing device 20 determines the operation algorithm of all digital elements, while generating all the necessary commands.

The first digital multiplexer 5, according to the control commands of the synchronizing device 20, sends the values of the module of the induction vector of the hypogeomagnetic field, measured by magnetometer 3, and the program values of this module written in advance to the block 22 of the input of the experiment program (technological program) into the RAM of the circuit 9 for comparing codes.

The second digital multiplexer 8, according to the control commands of the synchronizing device 20, sends to the digital memory of the digital discriminator 16 the values of the module of the geomagnetic field induction vector in real time and the value of the average module of the geomagnetic field induction vector for a given geographical point, which is the result of many years of monitoring of the geomagnetic field, for example, an international system INTERMAGNET.

The code comparison circuit 9 is equipped with random access memory, has an “equal to” output that controls the first driver 10 at the stop-start input and, through the inverter 11, the second driver 12 at the same input. In addition, through the “more - less” output of the circuit, a mismatch signal is generated in digital format and its sign between the values of the absolute value of the induction vector of the hypogeomagnetic field and its program value required by the conditions of the experiment (technology) at a given time.

The first digital-to-analog Converter 13 - standard version is designed to convert a digital signal mismatch circuit 9 code comparison in the analog control signal of the first driver 10.

The second digital-to-analog converter 17 is designed to convert the digital signal of the digital discriminator 16, which is proportional to the geomagnetic disturbance module, into an analog signal to control the angle of rotation of the camera.

The integrating amplifier 18 is designed to integrate the control DC voltage from the output of the second digital-to-analog converter 17 in order to give additional stability to the automatic control system.

The digital discriminator 16 is equipped with random access memory and is designed to isolate, at the command of the synchronizing device 20, a mismatch signal and its sign between the average value of the module of the geomagnetic field induction vector and its value measured in real time. The main function of digital discriminator 16 is to track all possible perturbations of the geomagnetic field, which are the result of solar activity and other factors of a random nature that may arise over a long period of the experiment (technological process).

The timer 21 is designed to temporarily bind the necessary values of the module of the vector of the intensity of the hypogeomagnetic field to the program of the experiment (technological process).

The operation of the device is as follows.

To describe the operation of the device, we accept the initial position.

The attenuation coefficient of the geomagnetic field by the shielding chamber is a structural parameter and, when the longitudinal axis of the chamber is oriented perpendicular to the direction of the geomagnetic field induction vector, has a maximum value. For example, it is 600.

We take the average statistical value of the module of the induction vector of the geomagnetic field at a given geographical point approximately equal to 60,000 nT.

In this case, the magnitude of the induction vector of the hypogeomagnetic field is naturally equal to 100 nT.

The magnitude of the induction vector of the perturbed geomagnetic field can reach 70,000 nT.

The magnitude of the geomagnetic field induction vector, measured in real time by a magnetometer, can theoretically range from 50,000 nT to 70,000 nT. Thus, the range of control of the tracking system for disturbances is selected ± 10,000 nT relative to the average 60,000 nT.

The proposed program, in accordance with which the set levels of the module of the induction vector of the hypogeomagnetic field in the shielding cylindrical chamber are set, depends on the technological process, which is due, for example, to the nature of the influence of the magnetic field on the biophysical sample placed inside the shielding chamber.

All module values of the induction vector of the hypogeomagnetic field are entered into the input block of the experiment program (technological process) using the keyboard built into the block.

The value of the modulus of the induction vector of the geomagnetic field is recorded in the input unit of the average value and is a reference value, in comparison with which the amplitude of the perturbations of the geomagnetic field and their compensation through the automatic control system are allocated.

When the device is turned on, the first driver 10 is in a passive state, the shaft of the first servomotor 14 is disconnected from the rotary table gearbox 2 (not shown in Fig. 4), the second driver 12 is in the active state, the shaft of the second servomotor 19 is by means of an electromechanical coupling (on 4 is not shown) is connected to the gear of the rotary table 2. The second magnetometer 6 by means of the second flux-gate sensor 7 of the magnetic field registers in real time the value of the module of the geom induction vector a magnetic field, which in digital format, at the command of a synchronizing device 20, is input through the second digital multiplexer 8 into the random access memory of the digital discriminator 16. On the other hand, the average value of the module of the geomagnetic field induction vector, characteristic of the geographical point of the technological process by means of the average value input unit 15 module of the induction vector of the geomagnetic field, at the command of the synchronizing device 20 through the second digital multiplexer 8 is entered also in the random access memory of the digital discriminator 16. The digital discriminator 16 generates a mismatch signal in digital format, which is converted into analog form by the second digital-to-analog converter 17 and fed through the integrating amplifier 18 to the control input of the second driver 12. The second driver 12 positions the second servomotor 19 and, therefore through the gearbox, the rotary table 2 with the shielding chamber 1 in the position when, firstly, the above error signal is “0” and, secondly, the readings of the first ma nitometra 3, the recording size of the vector field induction hypogeomagnetic module in real time, will be equal to 100 nT. Thus, at the first stage, the device is optimized and normalized according to the attenuation coefficient of the geomagnetic field and the preparation of the tracking system for the perturbations of the geomagnetic field is prepared.

Further, by means of the keyboard of the technological process program input block 22, the module values of the hypogeomagnetic field induction vector required by the experiment are entered into the RAM of the block. The second driver 12 is in a passive state, and the first driver 10 is in an active state. The shaft of the second servomotor 19 is disconnected by an electromechanical coupling from the gearbox of the rotary table 2 of the shielding chamber 1, and the shaft of the first servomotor 14 is connected to it through its electromechanical coupling. The first fluxgate magnetometer 3 by means of a fluxgate sensor 4, placed in the working area of the shielding chamber 1, registers in real time the value of the module of the induction vector of the hypogeomagnetic field, which through the first digital multiplexer 5 is fed into the random access memory of the code comparison circuit 9, to the second input of which in the same way its program value is supplied.

So, the initial tracking system for perturbations set the absolute value of the induction vector of the hypogeomagnetic field to 100 nT. At the same time, according to the program of the technological process for a given period of time, the biophysical object must be kept in the chamber with the value of this module equal to, for example, 200 nT. To set this value according to the commands of the synchronizing device 20 and the timer 21, the program value of the module of the induction vector of the hypogeomagnetic field from the input unit 22 is supplied through the first digital multiplexer 5 to the RAM of the code comparison circuit 9. At the output of the "more-less" circuit 9 code comparison, a mismatch signal is generated in digital format and the signal code is "more" or "less". This signal is converted into analog form by the first digital-to-analog converter 13 and, through the first driver 10, controls the first servomotor 14 in such a way that as a result of the rotation of the rotary table 2 with the camera 1, the mismatch signal decreases even when the magnitude of the module of the induction vector of the hypogeomagnetic field recorded first magnetometer, it will become equal to 200 nT, the code comparison circuit at its output “equals” generates a signal for the end of the software installation, while the first driver 10 is switched to passive with standing, and the second driver 12 - the active. Electromechanical couplings are transferred to the corresponding state by disconnecting the shaft of the first servomotor 14 from the gearbox of the rotary table 2 of the chamber 1 and connecting the shaft of the second servomotor 12 to it.

During the operation of the tracking system according to perturbations, the first magnetometer 3 in real time fixes within its error the current value of the module of the induction vector of the hypogeomagnetic field, equal to 200 nT.

After a predetermined time, depending on the program of the technological process, the synchronizing device 19 issues a command to the input unit 22 of the technological process program to establish a different value of the specified level of the module of the induction vector of the hypogeomagnetic field, for example 170 nT, again translating the first driver 10, the first servomotor 14 with the corresponding Electromechanical clutch in active state. In this case, the second driver 12, the second servomotor 19 with the corresponding coupling are transferred to the passive state. The process is repeated, as described previously, until the first magnetometer 3 fixes the module value of the induction vector of the hypogeomagnetic field equal to 170 nT. Then the servo system is reconnected according to disturbances, and the programming system is turned off.

If during the process the fact of a geomagnetic disturbance of various etiologies is recorded, the digital discriminator 16 of the tracking system will generate a mismatch signal in digital format proportional to the amplitude of this disturbance and, acting through the second digital-to-analog converter 17, integrating amplifier 18, the second driver 12, and the second the servomotor 19 will rotate the rotary table 2 with the shielding chamber 1, while changing the attenuation coefficient of the geomagnetic field in the direction of its uv Licheng until full, within the error compensation of the current disturbance.

Claims (3)

1. The way to ensure a given level of the module of the induction vector of the hypogeomagnetic field in the shielding cylindrical chamber, characterized in that the rotation of the shielding cylindrical chamber by an angle proportional to the first difference signal obtained by comparing the specified level of the module of the induction vector of the hypogeomagnetic field with the current value of the module of the induction vector of the hypogeomagnetic field measured inside the shielding cylindrical chamber in real time, the current value of the module of the hypogene induction vector is changed magnetic field until a predetermined level is established, after which the current value of the module of the induction vector of the hypogeomagnetic field is maintained at a given level by rotating the shielding cylindrical chamber by an angle proportional to the second difference signal obtained by comparing the average statistical value of the module of the geomagnetic field induction vector at a given geographical point with the current the magnitude of the induction vector of the external magnetic field measured outside the shielding cylindrical chamber in real ohm time. 2. A device for providing a given level of the module of the induction vector of the hypogeomagnetic field in the shielding cylindrical chamber, characterized in that it contains a first flux-probe three-component magnetometer of the hypogeomagnetic field with a sensor installed inside the shielding chamber, and a second flux-probe three-component magnetometer of the geomagnetic field with a sensor installed outside a shielding chamber, wherein the shielding chamber is rotatably mounted using the first and second servomotors, which alternately provide rotation of the shielding chamber, while the control input of the first servomotor is connected to the control output of the system for setting the level of the module of the induction vector of the hypogeomagnetic field connected by the information input to the information output of the first magnetometer and the control input to the first output of the control unit, and the control input of the second servomotor is connected with the control output of the automatic control system connected by the information input to the information output of the second ma Gnitometer and control input - with the second output of the control unit. 3. The device according to claim 2, characterized in that the system for setting the level of the module of the induction vector of the hypogeomagnetic field contains a process program input block, a first digital multiplexer, a code comparison circuit, a first digital-to-analog converter, a first driver, an automatic control and stabilization system for a given module level the induction vector of the hypogeomagnetic field contains a unit for inputting the average statistical value of the module of the geomagnetic field intensity vector, a second digital multiplexer, Digital the second discriminator, a second digital-to-analog converter, an integrating amplifier and a second driver, the control unit comprising a synchronizing device connected by an input to a timer output, the first magnetometer being connected by the information output to the first information input of the first multiplexer, and the second magnetometer being connected by its information output to the first information input of the second multiplexer, the input unit of the technological program output is connected to the second information input of the first multiplexer Xor, the output of the latter is connected to the input of the code comparison circuit, the output of which is “equal” to the stop input of the first driver and the inverter input, the output of which is connected to the stop input of the second driver, the analog control input of the first driver is connected to the output of the first digital-to-analog converter , the input of which is connected to the control output “more-less” of the code comparison circuit, the first driver is connected by its output to the input of the first servomotor mechanically connected to the rotary table shielding cam drive ery, while the input block of the average value of the module of the induction vector of the geomagnetic field is connected by its output to the second information input of the second multiplexer, the output of which, in turn, is connected to the information input of the digital discriminator, the output of the latter is connected to the input of the second digital-to-analog converter, the output of which is connected to the input of the integrating amplifier, connected by the output to the control input of the second driver, connected by the output to the input of the second servomotor, the output of which is is mechanically connected to the rotary table drive of the shielding chamber, the synchronizing device, with its first output, which is the first output of the control unit, is connected to the control inputs of the technological program input unit, the first digital multiplexer and code comparison circuit, and its second output, which is the second output of the control unit, is connected with the control inputs of the input block of the average value of the module of the induction vector of the geomagnetic field, the second multiplexer and digital discriminator.

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