RU2738098C1 - Azimuth determination method - Google Patents

Abstract

FIELD: instrument engineering.

SUBSTANCE: invention relates to instrument making and can be used in development, manufacture and operation of self-orienting gyroscopic systems for course indication and course and roll indication. Method of determining azimuth with gyroscopic system with heading gyroscope and course angle sensor consists in the fact that after switching on gyrocompass mode for initial bringing of main axis of course gyroscope in plane of meridian in north or south direction, bringing the main axis of the heading gyroscope to the plane of the meridian and fixing from the course sensor of the angle of the azimuth value, accelerating turning of the course gyroscope in the azimuth by an angle π and switching on the gyrocompass mode for re-adjustment. Further, the true azimuth value is determined according to the expression: A_tr=(A₁+A₂+π)/2 at A₁>A₂ or A_tr=(A₁+A₂-π)/2 at A₁<A₂, where A₁ is the azimuth value after first bringing the main axis of the heading gyroscope to the meridian plane, A₂ is the heading angle value in a position opposite to the first azimuth value. At positions A₁ and A₂ values of body (rhumb) corrections in the specified positions, determined by results of preliminary adjustment of the gyroscopic system, are taken into account, taking into account sign of their manifestation in specific positions of heading gyroscope depending on conditions of obtaining values of azimuth.

EFFECT: high accuracy of determining true azimuth with a self-oriented gyroscopic system.

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Description

The invention relates to the field of measuring technology and can be used in the development, manufacture and operation of systems of self-orienting gyroscopic heading and heading, intended for systems of navigation and georeferencing, guidance and aiming of mobile objects of ground equipment.

There is a known method for determining the true azimuth by a self-orienting gyroscopic system according to RF patent No. 2407989, in which the invariance of the true azimuth value to latitude changes is achieved by sequentially bringing the main axis of the heading gyroscope to the meridian plane in the north and south directions with fixing the azimuth values from the heading sensor A _N and A _S in the indicated positions, after which the value of the true azimuth is determined as

The disadvantage of the method for determining the true azimuth according to the patent of the Russian Federation No. 2407989 is that after the first alignment in the north direction and the accelerated turn of the course gyroscope in azimuth by the angle π, the main axis of the course gyroscope is brought into the meridian plane in the south direction, for which the polarity of the azimuthal indirect correction to the opposite. As a result, the implementation of the method requires the generation of an additional control signal and the presence of an additional switching device. In this case, due to the imperfect operation of the correction circuits (amplifiers), a change in the conditions for the arrival of the main axis of the course gyroscope to the south direction can be observed, which will lead to an error in determining the azimuth in the south direction and, accordingly, to an error in determining the value of A _ist , and, therefore, to violation of the invariance of the true azimuth value to the change in latitude.

A known method for determining the azimuth of a heading gyroscope with a heading angle sensor according to RF patent No. 2567406, taken as a prototype, free from these disadvantages, in which, after turning on the gyrocompass mode for the initial reduction of the main axis of the heading gyroscope to the meridian plane in the north or south direction, bringing the main axis heading gyroscope into the meridian plane and fixing the azimuth value A ₁ from the heading angle sensor, turn off the gyrocompass mode, make an accelerated turn of the heading gyroscope in azimuth through an angle π, turn on the gyrocompass mode again and determine the true azimuth value, according to the invention, after turning through an angle π, the mode the gyrocompass is turned on to bring the heading gyroscope into the meridian plane in the direction of the initial alignment, after which, within a given time interval, the values from the heading angle sensor and the time values corresponding to the moments of obtaining the values from the heading angle sensor, according to the obtained values, the speed of bringing the heading gyroscope into the meridian plane is calculated from the position of the heading gyroscope A ₁ + π, then additional turns are performed with operations to turn off and on the gyrocompass mode with the calculation, after turning on the gyrocompass mode, the speed of bringing the heading gyroscope into the meridian plane, as a result of performing the specified operations determine the position A ₂ , in which the speed of alignment is equal to zero, then carry out the determination of the value A _ist true azimuth according to the expression:

where A ₁ is the azimuth value after the first bringing the main axis of the course gyroscope into the meridian plane,

And ₂ is the value of the heading angle at which the alignment speed in the position opposite to the first azimuth value is zero.

The disadvantage of the method of the patent of RF №2567406 lies in the fact that due to the self-orienting gyroscopic system error that depends on the current position of the gyroscope relative to the course of the housing in azimuth, the azimuth value A ₁ and the azimuth value A ₂ at a position opposite to the first value azimuth, are determined with errors equal to the current hull (or, in other words, bearing) correction, determined for a given position of the heading gyroscope relative to the device body in azimuth when presetting the self-orienting gyroscopic system. As a result, the azimuth value (3) is also determined with an error. It was experimentally established that the value of the body correction for determining the azimuth when determining the value of the heading angle A _S in expression (1) as a result of bringing the heading gyroscope in the opposite direction by switching the sign of the indirect correction to the opposite one or the value of the heading angle A ₂ in expression (2), when where the speed of alignment without switching the sign of the indirect correction in the position opposite to the first value of the azimuth is equal to zero, corresponds to the corpus corrections determined during the preliminary adjustment of the self-orienting gyroscopic system during normal bringing to stable positions A _S or A ₂ with the corresponding positions of the body of the self-orienting gyroscopic system in azimuth , but taken with the opposite sign.

The invention is aimed at improving the accuracy of determining the true azimuth by the self-orienting gyroscopic system by eliminating the influence of the body error in determining the azimuth of the self-orienting gyroscopic system on the accuracy of determining the true azimuth.

при А₁>А₂ или

при А₁<А₂, перед определением значения истинного азимута с использованием процесса приведения курсового гироскопа в плоскость меридиана без переключения знака косвенной коррекции режима гирокомпаса проводят предварительную настройку системы самоориентирующейся гироскопической путем определения значений корпусных (румбовых) поправок в положениях курсового гироскопа, равномерно распределенных в азимуте в диапазоне углов от 0 до 360°, затем вводят в устройство памяти, работающее совместно с системой самоориентирующейся гироскопической, значения корпусных (румбовых) поправок определения азимута, а при определении значения истинного азимута после определения положения А₁ главной оси курсового гироскопа после первоначального приведения в плоскость меридиана и положения A₂ курсового гироскопа, противоположного первому положению курсового гироскопа, определяют значения корпусных (румбовых) поправок в указанных положениях A₁ и А₂, после чего в значении А₁, полученном в результате первоначального приведения главной оси курсового гироскопа в плоскость меридиана, учитывают значение корпусной (румбовой) поправки в положении курсового гироскопа A₁, а в значении А₂, полученного в положении, противоположном положению А₁ курсового гироскопа после предварительного приведения, учитывают значение корпусной (румбовой) поправки в положении курсового гироскопа А₂, но взятое с противоположным знаком.The specified technical result is achieved by the fact that in the known method of determining the azimuth with a heading gyroscope with a heading angle sensor, which consists in the fact that after turning on the gyrocompass mode for the initial bringing of the main axis of the heading gyroscope to the meridian plane, bringing the main axis of the heading gyroscope into the meridian plane and fixing with directional sensor of the azimuth value A ₁ , turn off the gyrocompass mode, make an accelerated turn of the directional gyroscope in azimuth by an angle π, after turning through an angle π, turn on the gyrocompass mode again to bring it into the meridian plane, then determine the value from the directional sensor of the angle A ₂ in position opposite to the first position localizer A gyroscope _1, the A ₂ value is then used to determine the true value of the azimuth according to the expression A _ist

for A ₁ > A ₂ or

at A ₁ <A ₂ , before determining the value of the true azimuth using the process of bringing the course gyroscope to the meridian plane without switching the sign of the indirect correction of the gyrocompass mode, pre-adjust the self-orienting gyroscopic system by determining the values of the corpus (bearing) corrections in the positions of the course gyroscope, evenly distributed in azimuth in the range of angles from 0 to 360 °, then enter into the memory device, working in conjunction with the self-orienting gyroscopic system, the values of the corpus (bearing) corrections for determining the azimuth, and when determining the value of the true azimuth after determining the position A1 _{of the} main axis of the course gyroscope after initial alignment into the plane of the meridian and the position A _{2 of the} heading gyroscope, opposite to the first position of the heading gyroscope, determine the values of the corpus (bearing) corrections in the indicated positions A ₁ and A ₂ , after which, in the value of A ₁ obtained as a result of then initial actuation major axis localizer gyroscope in the meridian plane, take into account the value housing (rumbovoy) amendments in position localizer gyroscope A ₁ and A ₂ value obtained at the position opposite to the position of A ₁ localizer gyro after the preliminary driving, take into account the value housing (rumbovoy) corrections in the position of the heading gyroscope A ₂ , but taken with the opposite sign.

In the proposed method for determining the azimuth, improving the accuracy of determining the true azimuth by the self-orienting gyroscopic system, eliminating the effect of changing the latitude of the location during the operation of the self-orienting gyroscopic system on the accuracy of determining the true azimuth is implemented as follows.

Preliminarily, the self-orienting gyroscopic system is tuned in bench conditions by determining the values of the hull (bearing) corrections in different positions of the course gyroscope using the standard process of bringing the meridian into the plane without switching the sign of the indirect correction of the gyrocompass mode. For this, the self-guided gyroscopic system is installed on a rotary stand. The body of the system is sequentially oriented using the turntable of the stand to positions uniformly distributed in azimuth in the range of angles from 0 to 360 °. In each position, the gyrocompassing process is performed with the determination of the azimuth value. Based on the obtained values, a graph of the azimuth values reduced to the initial value is plotted, depending on the values of the azimuth positions of the system body set by the stand. According to the obtained dependence as a deviation from the average azimuth value calculated from all the given measurements, the values of the hull (bearing) error are obtained depending on the azimuth values measured by the system. The process of measuring the hull (bearing) error for a self-orienting gyroscopic system is described in the AYUIZh.462515.013I1 setup and control instructions. System of self-orienting gyroscopic course-heading, JSC “VNII“ Signal ”[1] or in the instructions for setting and monitoring AYUIZh.462515.017I1 System of self-orienting gyroscopic heading-tenoning, JSC“ VNII “Signal” [2]. In the future, to eliminate the influence of the corpus (bearing) error, the obtained values are introduced as corrections into a memory device, which is part of a computing device operating in conjunction with a self-orienting gyroscopic system, and these corrections are taken into account in the readings of the self-orienting gyroscopic system. The device in which the hull (bearing) corrections of the self-orienting gyroscopic system are stored and taken into account can be the calculator of the system itself, as indicated, for example, in [2], or the coordinator of the autonomous gyro-course guidance system, as indicated, for example, in the manual for AYUIZh.462414.031RE ... Autonomous system gyroscopic self-orienting course guidance, JSC VNII Signal.

When determining the true azimuth by the self-orienting gyroscopic system after the first activation of the gyrocompass mode, bringing the main axis of the heading gyroscope to the meridian plane in the north (or south) direction, fixing the azimuth value A ₁ from the heading sensor, turning off the gyrocompass mode, sequential accelerated turn of the heading gyroscope in azimuth by the angle π, re-include the gyrocompass mode to bring the main axis of the course gyroscope into the meridian plane in the direction opposite to the initial alignment or in the direction in which the initial alignment was carried out. Thus with the course angle sensor is fixed azimuth second value A ₂ corresponding to the position of bringing the course gyro major axis in the meridian plane in the opposite direction bringing the original or position at which the driving speed at a position opposite to the first value of the azimuth A _1, is zero. The common thing for a measurement carried out in one way or another is that as a result of performing the described operations, the obtained azimuth values А _{2 are} almost opposite to the first measurement A ₁ and are equal (or almost equal) to each other.

After the first activation of the gyrocompass mode and bringing the main axis of the heading gyroscope to the meridian plane due to the action of moments, mainly from the heading gyroscope's own departure relative to the horizontal axis of sensitivity, as well as from other harmful moments, the main axis of the heading gyroscope deviates from the northern direction depending on latitude ϕ of the measurement location by ΔA

where ω is the value of its own drift relative to the horizontal axis of sensitivity and the equivalent drift away from harmful moments of the course gyroscope, Ω is the angular velocity of the Earth's rotation.

With positive values of ω, the main axis of the heading gyroscope deviates from the north to the east by an angle ΔA, while the azimuth value is recorded with an error from the heading angle sensor of the self-orienting gyroscopic system, namely:

where ΔА _к1 - frame error in position А ₁ .

Similarly, the value of the course angle А ₂ after bringing the main axis of the course gyroscope into the meridian plane in the opposite direction or the value of the course angle А ₂ , at which the speed of alignment in the position opposite to the first position of the course gyroscope after initial bringing into the meridian plane is equal to zero, are also fixed with error ΔА, while:

A ₂ = A + ΔA _{ist-π-ΔA k2,} when A _1> A _2;

where ΔА _к2 - frame error in position А ₂ .

The change in the sign of accounting for the error ΔA in (5) shows that with positive values of ω in position А _{2, the} main axis of the course gyroscope deviates from the southern direction also to the eastern direction by the angle ΔА. In the case of initial reduction to the south direction, the situation is similar, since the error ΔA is related to the gyroscope body. When adding the values А ₁ and А ₂ in (2), errors in (4) and (5), equal in magnitude and opposite in sign, are excluded. Thus, the claimed method automatically compensates for errors arising from the action of its own departure relative to the horizontal axis of sensitivity and the equivalent departure from harmful moments of the course gyroscope, which eliminates the influence (3) of changes in the systematic component of the course gyroscope departure during the operation of the self-orienting gyroscopic system. In this case, by periodically (associated with performing routine maintenance at the facility) performing the operations described in the method, the invariance of the true azimuth value (2) to the change in latitude during the operation of the self-orienting gyroscopic system can be ensured.

Additionally, expressions (2) take into account the angular distance π between A ₁ and A ₂ . In this case, a specific sign of accounting π is chosen when comparing the values of A ₁ and A ₂ on the basis that the values of A ₁ and A _{2 are} always opposite (differ by an angle close to π) in azimuth and are in the range of angles from 0 to 2π.

However, the presence of the bearing or hull error in determining the azimuth reduces the accuracy of determining the azimuth by expression (2). It has been experimentally established that the value of the body correction for determining the azimuth when determining the value of the heading angle A ₂ as a result of bringing the heading gyroscope in the opposite direction by switching the sign of the indirect correction to the opposite one or the value of the heading angle A ₂ , at which the speed of pointing without switching the sign of the indirect correction in the position , opposite to the first value of the azimuth, is equal to zero, corresponds to the hull correction determined during the preliminary adjustment of the system during normal bringing to a stable position А ₂ with the corresponding position of the housing of the system in azimuth, but taken with the opposite sign, which is taken into account in the sign of the value ΔА _к2 in the expression ( 5). In this case, expression (2) taking into account (4) and (5) will have the form:

Whence the error in determining the true azimuth is

With positive values of harmful moments in the opposite A ₁ position A ₂ , leading to the appearance of a hull or bearing error, the main axis of the course gyroscope deviates to the east direction by an angle ΔA _k2 . The change in the sign of taking into account the error ΔА _к2 in (5) with respect to the sign of accounting for the error ΔА _к1 in (4) shows that during the initial reduction to the direction of the meridian, the situation is similar, - the main axis of the heading gyroscope also deviates to the east direction, but at a different angle ΔА _k1 , in view of the fact that the hull or bearing error changes its value and is associated with the gyroscope body. When adding the values of A ₁ and A _2, errors ΔА _к1 , ΔА _к2 , opposite in sign, but different in magnitude, are not excluded, leading to an error in determining the azimuth (7). To eliminate the error in determining the azimuth (7) from the hull error, the proposed method compensates for the hull or bearing error with appropriate corrections, taking into account the sign of their manifestation in specific positions of the course gyroscope, depending on the conditions for obtaining the azimuth values. When initially brought to position A _{1, the} error ΔA _k1 has a sign obtained during the initial setup of the system with the determination of the frame error. When re-bringing, when determining the position A _2, as a result of a change in the sign of the indirect correction for alignment in the opposite direction or a change in the position of the course gyroscope to the opposite in azimuth without changing the sign of the indirect correction with bringing in the original direction, the sign of harmful moments acting in position A ₂ , leading to the error ΔА _к2 . As a result, the error ΔА _к2 in position А ₂ , obtained as a result of performing the actions of the method, has a sign opposite to the value obtained during the initial setup of the system with the determination of the frame error, which is taken into account during measurements. This increases the accuracy by compensating for the influence of the hull (bearing) component of the azimuth determination error.

The method is implemented using a self-orienting gyroscopic system with programmable modes; gyrocompass, accelerated heading gyroscope turn, heading storage. In this case, the implementation of the method is possible for already operating systems without modifying their hardware, as well as using the existing production process for their adjustment. The method is industrially applicable, which is confirmed by its successful approbation on prototypes of systems of self-orienting gyroscopic course directions.

Claims (1)

A method for determining the azimuth by a gyroscopic system with a heading gyroscope and a heading angle sensor, which consists in the fact that after turning on the gyrocompass mode for the initial alignment of the main axis of the heading gyroscope in the meridian plane, bringing the main axis of the heading gyroscope into the meridian plane and fixing the azimuth value A from the heading sensor _1, is turned off gyrocompass mode, produce rapid reversal course gyro azimuth by an angle π, after turning through an angle of π include gyrocompass mode repeatedly for actuating the meridian plane, thereafter determined course angle sensor value a ₂ at a position opposite the first position localizer gyroscope A ₁ , while the value of A _{2 is} then used to determine the value of the true azimuth A _ist according to the expression

for A ₁ > A ₂ or

at A ₁ <A ₂ , characterized in that before determining the value of the true azimuth, the self-orienting gyroscopic system is pre-adjusted using the process of bringing the course gyroscope to the meridian plane in the gyrocompass mode, which consists in determining the values of the corpus (bearing) corrections in the positions of the course gyroscope, uniformly distributed in azimuth in the range of angles from 0 to 360 °, then the values of the hull (bearing) corrections for determining the azimuth are entered into the memory device operating in conjunction with the self-orienting gyroscopic system, and when determining the value of the true azimuth after determining the position A1 _{of the} main axis of the heading gyroscope after the initial bringing into the plane of the meridian and the position A _{2 of the} course gyroscope opposite to the first position of the course gyroscope, taking into account the results of the preliminary adjustment, the values of the corpus (bearing) corrections are determined in the indicated positions A ₁ and A ₂ , after which in the sign chenii A _1, resulting from the initial driving course gyro major axis in the meridian plane, take into account the value housing (rumbovoy) amendments in position localizer gyroscope A ₁ and A ₂ value obtained at the position opposite to the position A ₁ of the course of the gyroscope due to the pre bringing take into account the value housing (rumbovoy) at position correction course gyroscope a ₂ as defined in step presetting gyroscopic system, but taken from the opposite sign.