RU2787971C1 - Method for autonomous orientation of objects in near-earth space - Google Patents

Abstract

FIELD: moving objects strapdown autonomous orientation.

SUBSTANCE: invention relates to a method for strapdown autonomous orientation of moving objects in near-Earth space. For the orientation of moving objects, primary instrument information is formed about the apparent acceleration vector

and the vector of the resulting magnetic field

according to the signals of pre-calibrated triaxial blocks of accelerometers and magnetometers, as well as on the subsequent processing of this information, taking into account the use of navigation information received from a satellite navigation system, correct taking into account the results of previously performed technological calibrations, they are brought to the axes of the orthonormal basis m=XYZ associated with the object

then, based on the use of navigation information from the satellite navigation system, the components of the vectors of the Earth's gravity field

of the geomagnetic field

and the apparent acceleration

reduced to the axes of the basis are calculated q, and finally, the vectors

corrected and reduced to the bases m and q are used to determine the orientation parameters of the object using non-integral strapdown processing algorithms vector information.

EFFECT: increased accuracy of solving problems of orientation of moving objects.

1 cl, 2 dwg, 5 tbl

Description

The invention relates to the field of on-board instrumentation and automation, can be used to solve problems of autonomous orientation when controlling ground, floating, aircraft, ballistic and space vehicles in near-Earth space.

When solving problems of spatial orientation of moving objects (MO) in near-Earth space, preference is given to autonomous orientation methods corresponding to strapdown and gyroscope-free technologies [1, 2]

There is a known geometric method for autonomous orientation of software in near-Earth space based on the use of platform gyroscopic technologies [3, 4].

This method is based on the principles of physical reproduction (in a geometrical way) in space of two or three basic reference directions using gyroscopic orientation systems (GSO). Schemes for constructing a GSO may involve the implementation of various options for circuitry and design solutions [3, 4]:

- combinations of three-degree (free and adjustable) gyroscopes in gimbals (direction gyroscopes, gyrocompasses, gyrorbitants, gyro-verticals, gero-verticants, etc.),

- gyroscopic headings (KVG),

- combinations of uniaxial (OGS) and biaxial (DGS) gyrostabilizers,

- triaxial indicator, power and indicator-power gyrostabilizers (TGS) with gyro-stabilized platforms (GSP),

- systems of three and several single-axis gyrostabilizers (OGS),

- gyroazimuth horizons (GAG) based on the use of OGS, DGS, TGS schemes, etc. In all variants of GSO construction, the principle of physical

modeling of reference bases, reproduced materially using three unit vectors:

- векторы кинетических моментов и их модули для i-ых гироскопов.where

- vectors of kinetic moments and their modules for the i-th gyroscopes.

отсчетный базис

строят на основе следующих ортов:For GSO schemes built taking into account the use of only two gyroscopes with kinetic moments

reference basis

build on the basis of the following vectors:

определяемых по формулам (1) или (2), для любой схемы ГСО представляет собой неортогональный и нестационарный базис (в силу проявления геометрических свойств кардановых подвесов и свойств астатизма гироскопов).In the general case, the reference coordinate system built on the basis of unit vectors

determined by formulas (1) or (2), for any scheme, the GSO is a non-orthogonal and non-stationary basis (due to the manifestation of the geometric properties of gimbals and the properties of astatism of gyroscopes).

The disadvantages of the geometric method of autonomous software orientation based on the use of GSO include the following:

- large dimensions and masses of GSO,

- the need to carry out GSO correction operations, because gyroscopes "leave in space" due to the manifestation of their drift, due to the property of astatism,

- the use of GSO on software imposes some restrictions on the spatial maneuvers of objects due to the manifestation of the geometric properties of the knockout of gyroscopes, due to the phenomenon of "frame folding" of gimbal suspensions.

Giving the GSO with gimbals the properties of stability, non-knockout, spatial all-mode and all-maneuverability is achieved by complicating the circuitry and design solutions (an additional servo frame is introduced, which is worked out in the position of the gyroscope stability using the servo system, and correction from additional reference systems is also introduced). This improvement leads to an even greater degree of deterioration in the overall and mass characteristics of the GSO, as well as to a decrease in manufacturability, efficiency, and operational reliability.

This fact has led to the fact that in the last 20-30 years, specialists in the field of software control, when solving problems of spatial autonomous orientation of objects, give preference to strapdown and gimbals-free technologies [1-5].

Known methods of spatial autonomous strapdown orientation software in near-Earth space, combined into a single group of methods of three-dimensional extended inertial orientation (TRIO) [1-5]. Variants of methods for strapdown autonomous inertial orientation of software (TRIO methods) differ from each other primarily in the ways of describing the geometry and kinematics of the rotational motion of an object [2, 3, 6].

As the initial mathematical model of the rotational motion of any software in space in all methods of TRIO, the kinematic equation of rotation of a rigid body is taken:

- вектор абсолютной угловой скорости вращения объекта в инерциальном пространстве, измеряемый с помощью блока гироскопов,where

- the vector of the absolute angular velocity of rotation of the object in inertial space, measured using a block of gyroscopes,

- вектор переносной угловой скорости вращения объекта вместе с вращающейся Землей в инерциальном пространстве,

- the vector of the portable angular velocity of rotation of the object together with the rotating Earth in inertial space,

- вектор относительной угловой скорости вращения объекта относительно Земли.

- the vector of the relative angular velocity of the object's rotation relative to the Earth.

On the basis of the vector equation (3), first, the kinematic equations of the rotational motion of the software in space are formed, and then the integral algorithms for processing inertial information for various variants of the TRIO, expressed in terms of various orientation parameters [2, 3, 6].

TRIO integral algorithm in terms of three-dimensional parameters (Euler angles) [6]:

TRIO integral algorithm in terms of four-dimensional parameters (Rodrigues-Hamilton parameters) in quaternion and vector-matrix forms [17]:

TRIO integral algorithm in terms of nine-dimensional parameters (direction cosines of the matrix A (3 × 3) of the orientation of the software) [3, 4, 6, 17]:

Algorithms (4) - (8) use the following designations:

- оценки эйлеровых углов (углов курса, тангажа (дифферента), крена(вращения), соответственно),

- estimates of Euler angles (angles of heading, pitch (trim), roll (rotation), respectively),

- оценки кватернионов конечного поворота и вектора

- estimates of quaternions of final rotation and vector

знак кватернионного произведения кватернионов,

sign of the quaternion product of quaternions,

- квадратные матрицы (4×4),

- square matrices (4×4),

- оценка матрицы ориентации ПО (3×3),

- evaluation of the software orientation matrix (3×3),

- обратная матрица (3×3) при векторе

- inverse matrix (3×3) with vector

- тензоры векторов

- vector tensors

- оценки начальных значений эйлеровых углов, кватерниона и матрицы ориентации, соответственно.

- estimates of the initial values of the Euler angles, quaternion and orientation matrix, respectively.

In the information processing algorithms (4) - (8), in order to take into account the estimates of the initial parameters of the orientation of the software in all TRIO methods, the operation of the initial autonomous alignment (IAV) is preliminarily performed [1-6].

измеряемые с помощью трехосного блока гироскопов (ТБГ), находятся под знаком интеграла. В реальных условиях показания ТБГ содержат наряду с полезными сигналами

мультипликативные

и аддитивные

погрешности:In all integral orientation algorithms PO (4) - (8) components of the angular velocity vector

measured using a triaxial gyroscope unit (TBG) are under the integral sign. In real conditions, TBG readings contain, along with useful signals

multiplicative

and additive

errors:

)

)

с помощью ТБГ видно, что всем вариантам способов ТРИО ПО характерен общий недостаток, заключающийся в накоплении погрешностей во времени, связанном с процессом интегрирования как полезных сигналов, так и ошибок гироскопов

From the analysis of integral algorithms for orientation of software (4) - (8) taking into account expressions (9) for real measurements

using TBG, it can be seen that all variants of the TRIO software methods are characterized by a common drawback, which consists in the accumulation of errors in time associated with the process of integrating both useful signals and gyroscope errors

Due to the manifestation of this general drawback, all methods of inertial orientation of the software have limitations on the time of operation of the BSO or require the use of additional correction techniques.

For this reason, the efforts of specialists in the field of software control since the end of the 20th century have been aimed at eliminating this main drawback by searching for and developing gyroscope-free methods of autonomous orientation, in particular, methods of autonomous orientation based on the processing of information about geophysical fields (GFP).

There is a known method of autonomous orientation software in space, based on the formation and processing of two-vector or three-vector information received from pairs or triplets of triaxial blocks of gyroscopes, accelerometers, magnetometers [7].

In the scientific and technical literature, the method is called the method of analytical horizon-compassing (AGC). The AGK method is implemented in three versions:

- two-vector AGK based on inertial information about vectors

- two-vector AGK based on magneto-intertial information about vectors

- three-vector combined AGK based on the combination of two-vector methods

In variants of the AGK method, the designations of HFP vectors are accepted:

- вектора напряженности поля тяжести Земли (ПТЗ),

- the intensity vector of the Earth's gravity field (PTZ),

- вектора напряженности магнитного поля Земли (МПЗ),

- vector of the Earth's magnetic field (EMF),

- вектора угловой скорости собственного суточного вращения Земли.

- the vector of the angular velocity of the Earth's own daily rotation.

получаемую с помощью трехосных блоков акселерометров (ТБА), используют для решения задачи аналитического горизонтирования (АГ), т.е. задачи определения углов

отклонения ПО от плоскости горизонта аналитическим путем на основе алгоритмической обработки информации ТБА в связанном с объектом базисе т:In all three variants of the AGK method, information about the vector

obtained using triaxial accelerometer units (TBA) is used to solve the problem of analytical leveling (AG), i.e. angle detection problems

deviations of software from the plane of the horizon analytically based on the algorithmic processing of TBA information in the basis t associated with the object:

The components of the vector referred to the axes of the geographic basis (N - the direction to the North, H - the direction of the vertical of the place, E - the direction to the East) are calculated based on the use of the basic gravimetry equation [8]:

- ускорение свободно падающего тела на экваторе,where

is the acceleration of a freely falling body at the equator,

a - the semi-major axis of the reference ellipsoid of the figure of the Earth,

a = 6378245, m,

h - geographical height, h = r - R,

R - average radius of the Earth, R=6378211 m,

α ² is the square of the eccentricity of the Earth's compression,

b - semi-minor axis of the figure of the Earth, b=6356863 m,

ϕ - geographical latitude of the observation point,

q is the ratio of centripetal acceleration to acceleration at the equator:

Ω is the angular velocity of the Earth's rotation,

точки наблюдения с координатами

вычисляют по формуле:Radius vector

observation points with coordinates

calculated by the formula:

вычисленных по формулам (10), (11), формируют уравнение АГ:Based on component vectors

calculated by formulas (10), (11), form the AG equation:

- матрицы (3×3) углов крена γ и тангажа ϑ.where

- matrices (3×3) of roll angles γ and pitch ϑ.

By solving the scalar equations obtained from the vector-matrix equation (15), the AG algorithms are formed:

After solving the AG problem, analytical compensating equations (AC) are compiled for two options:

- for analytical inertial compassing (AQI),

- for magnetometric analytical compassing (MAC), (g T - AK).

- транспонированные матрицы (3×3) углов тангажа и крена ПО,where

- transposed matrices (3×3) of pitch and roll angles,

- проекции вектора

на оси связанного базиса m (определяют по показаниям трехосного блока магнитометров (ТБМ))

- vector projections

on the axis of the associated basis m (determined by the readings of a triaxial block of magnetometers (TBM))

- проекции вектора

МПЗ на оси географического базиса q (вычисляют по модели нормального МПЗ [9],

- vector projections

EMF on the axis of the geographical basis q (calculated according to the normal EMF model [9],

- матрица (3×3) курса ПО. Уравнения АК (17) и (18) справедливы только в режиме неподвижности (ПО (в режиме ZUPT), при котором выполняются соотношения (10) и условия для показаний ТБГ:

- matrix (3×3) of the software course. The AC equations (17) and (18) are valid only in the immobility mode (in the ZUPT mode), in which the relations (10) and the conditions for the TBG indications are satisfied:

From the solutions of equations (17) and (18), the AK algorithms (AKI and MAK) are obtained.

AQI algorithm

MAC algorithm (g T - option):

And

To improve the accuracy of solving the AGK problem, as well as to ensure the conditions for all-mode and stability of the algorithms, sometimes the AKI and MAK methods are performed jointly in one method (AGK variant) using extended magneto-inertial information [10, 11].

а при работе в средах с аномальными магнитными свойствами вычисляют параметры ориентации по сигналам

. Таким образом, обработку многомерной магнито-инерциальной информации

выполняют по схеме реконфигурации алгоритмов (g Ω -АГК или g T-АГК).The method for orienting an inclinometer as part of an underground projectile in a well [11] includes measuring the projection on the axis of the associated basis of the magnetic field intensity by ferrosondes, measuring the projection of the acceleration of a freely falling body with accelerometers, measuring the projection of the angular velocity of the Earth's rotation with gyroscopes, converting primary signals and determining the angles of the object's spatial orientation. At the same time, the error of the gyroscopes is estimated using information from the satellite navigation system (SNS) and the values of the gyroscope drifts are corrected taking into account information from the fluxgates. Moreover, in the absence of magnetic anomalies, the orientation angles of the software are calculated from the TBM signals

and when working in media with anomalous magnetic properties, the orientation parameters are calculated from the signals

. Thus, the processing of multidimensional magneto-inertial information

perform according to the scheme of reconfiguration of algorithms (g Ω -AGK or g T-AGK).

In the absence of magnetic anomalies in the environment, the g T -AGK scheme is implemented using a non-gyroscope magneto-accelerometric module (TBM+TBA). In the presence of magnetic anomalies and the manifestation of external magnetic interference, autonomous orientation is implemented according to the g Ω-AGK scheme using only inertial information (TBA + TBG).

A common disadvantage of the AGK method in all variants (g Ω, gT and g Ω T) are restrictions on the conditions for using the measuring module (TBA, TBM, TBG) in the form of a requirement to execute the software stop mode (ZUPT mode).

полюсов, а также не обеспечивают необходимой точности решения задачи автономной ориентации в околополярных районах (с географической широтой

из-за близости векторов

к условиям квазиколлинеарности

В этих же районах проявляется повышенная чувствительность алгоритмов АГК к погрешностям первичных измерений

In addition, the AQI (20) and MAK (21) algorithms degenerate in geographic (cosϕ = 0) and geomagnetic regions.

poles, and also do not provide the necessary accuracy of solving the problem of autonomous orientation in circumpolar regions (with a geographic latitude

due to the proximity of vectors

to the conditions of quasicollinearity

In the same areas, an increased sensitivity of AGK algorithms to errors in primary measurements is manifested.

Taking into account the noted shortcomings, the AGK method has mainly found practical application for solving problems of NAV PO in prelaunch conditions [12].

и инерциальном

каналах измерений.However, in these cases, in order to improve the accuracy of solving the problem of autonomous orientation of the software, it is necessary to minimize errors in the magnetometric

and inertial

measurement channels.

из географического базиса

в связанный с объектом базис

и в последующем решении этого уравнения с целью формирования алгоритмов обработки многомерной геофизической информации (ГФИ) и преобразования ее в пилотажно-навигационную информацию (ПНИ) о параметрах ориентации объекта [13].There is a known method of autonomous spatial orientation (APO) software, which consists in compiling a matrix equation characterizing the transformation of HFP vectors

from geographic basis

to the basis associated with the object

and in the subsequent solution of this equation in order to form algorithms for processing multidimensional geophysical information (GPI) and converting it into flight navigation information (PNI) about the object orientation parameters [13].

и поэтому назван способом ориентации векторным автономным (СОВА).The method operates with information about HFP vectors

and therefore it is called the autonomous vector orientation method (SOVA).

МПЗ

и поля вращения Земли

в географическом q и m связанном базисахBased on the available information, the PTZ vectors are preliminarily calculated

MPZ

and the Earth's rotation fields

in geographic q and m related bases

вычисляют с учетом результатов предварительно выполненных метрологических тарировок и технологических калибровок в соответствии с расширенным уравнением Пуассона [14]:Vector

calculated taking into account the results of previously performed metrological calibrations and technological calibrations in accordance with the extended Poisson equation [14]:

- вектор напряженности результирующего магнитного поля, сформированного по показаниям ТБМ и приведенного к осям приборного отсчетного базиса р.where

- the intensity vector of the resulting magnetic field, formed according to the readings of the TBM and reduced to the axes of the instrument reference basis p.

- вектор напряженности МПЗ в точке наблюдения, приведенный к географическому базису q,

- EMF intensity vector at the observation point, reduced to the geographical basis q,

- компоненты вектора напряженности магнитного поля объекта (МПО), отнесенного к осям связанного базиса m,

are the components of the object's magnetic field strength vector (MFO), referred to the axes of the associated basis m,

- аналогичные компоненты вектора, обусловленного влиянием электромагнитных источников (ЭМИ) помех,

- similar components of the vector, due to the influence of electromagnetic sources (EMR) of interference,

- единичная матрица (3×3),

- identity matrix (3×3),

- матрица коэффициентов Пуассона (3×3),

- matrix of Poisson's ratios (3×3),

- матрица погрешностей сборки ТБМ (3×3),

- TBM assembly error matrix (3×3),

- матрица погрешностей монтажа ТБМ на объекте (3×3).

- error matrix of TBM installation at the facility (3×3).

в осях географического q базиса вычисляют с учетом данных СНС

по моделям нормальных ГФП [8, 9, 14]:Vector components

in the axes of the geographical q basis is calculated taking into account the SNA data

according to normal HFP models [8, 9, 14]:

The geomagnetic potential is represented using spherical Gauss series [8]:

where m, n - degree and order of expansion terms,

- присоединенные функции Лежандра.

are associated Legendre functions.

в географическом базисе [1, 2]:Based on the navigation information (ϕ, λ, h) received from the SNS, the components of the apparent acceleration vector are calculated

in the geographical basis [1, 2]:

where r _ϕ , r _λ are the radii of curvature of an equidistant reference ellipsoid [8].

определяют на основе данных СНС [1, 2]:Vector components

determined on the basis of SNA data [1, 2]:

определяют путем численного дифференцирования.Vector

determined by numerical differentiation.

в связанном базисе, а также путем вычисления дополнительных векторов [13] в базисах m и q:GPI is extended by calculating, based on the vector information recovery method [15], the vector

in the associated basis, as well as by calculating additional vectors [13] in the m and q bases:

Based on the vectors calculated by formulas (11) - (13), (26) - (33), (3), (23), the APO matrix equation is compiled under conditions of functional information redundancy:

In accordance with the principle of decomposition, the matrix equation (34) is divided into particular matrix identification equations with square matrices (3) of the form:

- матрица приборной информации и ГФИ в связанном базисе m (3×3),where

- matrix of instrument information and GFI in the associated basis m (3×3),

- матрица идентификации (3×3) для k-ого варианта.

- identification matrix (3×3) for the k-th option.

The maximum possible number of options for constructing matrix identification equations of the form (35) is

например,

For practical purposes, for reasons of saving the amount of RAM of the onboard computer, it is sufficient to use a limited number of options

for example,

APO algorithms for the COBA method are obtained by inverting the identification equations (35):

матрицы ориентации

для к-ого варианта.According to the APO algorithms (37), estimates of the direction cosines are calculated

orientation matrices

for the th option.

Use the operation of comparing estimates (37) and calculating the aligned estimate of the orientation matrix

Based on the calculated values of the direction cosines of the orientation matrix, the estimates of the Euler angles are determined using the formulas [13]:

а также положение ПО относительно осей географического базиса (q=NHE) определяют с помощью табл.1, 2, 3.Values, signs of estimated Euler angles

as well as the position of the software relative to the axes of the geographical basis (q=NHE) is determined using tables 1, 2, 3.

в способе СОВА используют три блока векторных ДПИ-ТБА, ТБГ, ТБМ. На основе этой ППИ могут быть реализованы трехвекторные и двухвекторные алгоритмы отработки информации (23) - (39). За счет этого реализуют условия функциональной избыточности информации, обеспечивающие свойства отказоустойчивости СОН и ее работоспособность в резервно-аварийных режимах (РАР). При этом допускается отказ любого блока или любых датчиков в пределах одного блока без потери работоспособности в РАР.For the formation of primary instrument information

in the COBA method, three blocks of vector DPI-TBA, TBG, TBM are used. Based on this PPI, three-vector and two-vector algorithms for processing information (23) - (39) can be implemented. Due to this, the conditions of functional redundancy of information are implemented, providing the fail-safe properties of the SN and its operability in standby emergency modes (RAR). In this case, failure of any block or any sensors within one block is allowed without loss of operability in the PAP.

The advantage of the COBA method is that for its implementation it is not required to perform the operations of the initial autonomous exhibition (NAV) SON. Disadvantages of the SOVA method:

- the use of TBG leads to a decrease in the accuracy of solving the problem of autonomous orientation due to the drift of gyroscopes,

- the complexity of information processing algorithms, taking into account the functional redundancy of information in the COBA method, increases the requirements for the computational characteristics of the microcontroller (speed, bit grid length, information performance).

магнитометрической

и инерциальной

информации [16].Known non-gyroscope method of semi-autonomous two-vector orientation software in space, based on the integrated use of: satellite navigation

magnetometric

and inertial

information [16].

This method is closest to the claimed method and therefore taken as a prototype.

и спутниковой

информации (по аналогии со способом векторного согласования TRIAD А).In the magnetic-inertial-satellite method (MISS DIADA), the problem of semi-autonomous orientation of the software is solved on the basis of complex processing of the two-vector

and satellite

information (by analogy with the TRIAD A vector matching method).

оценок направляющих косинусов

матрицы

ориентации ПО с последующим определением эйлеровых углов

Способ МИСС DIADA является частным случаем способа СОВА [13]. К достоинствам способа МИСС DIADA следует отнести следующее:The essence of the MISS DIADA method lies in the calculation based on the primary magnetic-inertial information

direction cosine estimates

matrices

software orientation followed by determination of Euler angles

The MISS DIADA method is a special case of the COBA method [13]. The advantages of the MISS DIADA method include the following:

- the absence of TBG signals with gyroscope drift in the PRS contributes to an increase in the accuracy of solving the software orientation problem,

- processing of information according to the MISS DIADA algorithms can be turned on and off at any time during the operation of the attitude control system without first performing NAV operations.

Disadvantages of the MISS DIADA method:

- the MISS DIADA method does not provide conditions for improving the accuracy of solving the software orientation problem due to the fact that the magnetometric channel (from TBM) is built according to rough algorithms that do not take into account the influence of destabilizing factors associated with the magnetic field of the object (MFO) and electromagnetic sources (EMR) of interference , as well as those associated with technological errors in the assembly and installation of TBM,

строят не географический отсчетный базис

а условный повернутый относительно базиса q трехгранник, с осями, направления которых определяют с помощью ортов, не совпадающих с ортами

:- in information processing algorithms in the MISS DIADA method based on unit vectors

build a non-geographic reference basis

and a conditional trihedron rotated relative to the basis q, with axes whose directions are determined using orts that do not coincide with the orts

:

склонной к разрыву

- possible malfunction of the MC due to the fact that in the algorithms for processing information according to the MISS DIADA method, the operation of calculating the tangent function is used

prone to breaking

- the orientation system built according to the MISS DIADA method does not have increased reliability and fault tolerance in PAP due to the absence of a condition for functional redundancy of information.

At the same time, the implementation of the two-vector MISS DIADA method, taking into account the elimination of the noted shortcomings, creates the prerequisites for the development of a small-sized two-unit (TBA, TBM) gyroscope-free semi-autonomous strapdown attitude control system (BSO). The practical use of such a gyroscope-free BSO is very attractive and effective both in production (manufacturability, economy) and in operation (reliability, small size and miniaturization), especially for UAVs.

The objective of the present invention is to develop a method for autonomous strapdown orientation software in near-Earth space, free from the disadvantages of analogs and prototype.

The solution of the problem is achieved by improving the method of processing magnetic-inertial-satellite information (MIS information):

- by improving the algorithms for processing information in the magnetometric channel, in order to take into account the technological features of TBM and the magnetic properties of the software itself,

- due to the development of more advanced and efficient algorithms for processing MIS information in accordance with the technology of algorithmic support for autonomous spatial orientation (APO) [13].

The proposed method for solving the problem of autonomous orientation of software in near-Earth space, the authors called the "magnetic-inertial method for determining the values of A" (MIMOSA) due to the fact that it allows you to determine the nine-dimensional orientation parameters - the direction cosines of the orientation matrix A.

ПО путем комплексной обработки МИС-информации с учетом технологических особенностей магнито-метрического канала с последующим вычислением оценок эйлеровых углов

ориентации объекта по невыбиваемым всережимным алгоритмам.The essence of the proposed method (MIMOSA) is to determine the estimates of the direction cosines of the orientation matrix

Software by complex processing of MIS-information, taking into account the technological features of the magnetometric channel, followed by calculation of estimates of Euler angles

orientation of the object according to non-knockout all-mode algorithms.

The proposed method is illustrated with the help of Fig. 1, 2. In Fig. 1 shows a functional diagram of the MIMOSA method,

1 - block of operations of technological (instrumental and object) calibrations,

2 - block of operations for the formation and conversion of primary instrument information (PDI),

3 - a block of computational operations in the MC according to the MIMOSA algorithms,

4 - a block of computational operations in the MK according to the CASCADE algorithms.

FIG.2 shows a diagram of the algorithmic support of the MIMOSA method.

5 - algorithms for technological support of the module (ATOM),

6 - MIS-information processing algorithms (MIMOSA),

7- complex algorithms for self-control and combined autonomous diagnostics (CASKAD).

The essence of the MIMOSA method lies in the sequential execution of measurement operations, the formation of PPI and its combined processing (FIGS. 1, 2):

1. In advance (before the start of the software), the operations of metrological calibration and technological calibration of the magnetometric and inertial measurement channels (item 1 in Fig. 1) are performed. Technological operations are performed according to the method described in the scientific and technical literature [14].

The processing of technological information (TI) is performed according to the algorithms of the technological support of the module (ATOM) (pos.5 in Fig. 2).

в приборном измерительном базисе

с учетом данных технологических калибровок выполняют операции коррекции показаний блоков (ТБА, ТБМ) и приведения их к ортонормированным осям связанного базиса m=XYZ [13, 14] (поз.2 на Фиг. 1):2. Based on the results of measurements of vectors

in instrumental measuring basis

taking into account the data of technological calibrations, operations are performed to correct the readings of the blocks (TBA, TBM) and bring them to the orthonormal axes of the associated basis m=XYZ [13, 14] (pos. 2 in Fig. 1):

- транспортированная матрица монтажа модуля на объекте,where

- transported module mounting matrix on site,

- обратные матрицы сборки ТБМ и ТБА, соответственно.

- inverse assembly matrices of TBM and TBA, respectively.

3. Perform the basic operations of processing MIS information algorithms MIMOSA (pos.3 in Fig. 1, pos.6 in Fig. 2).

в географическом базисе q по формулам (27)-(32) с учетом использования навигационной информации от СНС

Calculate components of vectors

in the geographical basis q according to formulas (27) - (32) taking into account the use of navigation information from the SNA

Calculate an additional vector

in bound (t) and geographic (q) bases:

Taking into account the calculated vectors, the main equation of the MIMOSA method is compiled in matrix form:

Or in compact forms:

where Р is the instrument information matrix, N is the identification matrix (3×3).

углов между ортами связанного

и географического

базисов:The orientation matrix of software A is determined through the direction cosines

angles between the unit vectors of the connected

and geographical

bases:

по способу МИМОЗА:By inverting the matrix equation (45) (or (46), (47)) a basic information processing algorithm is obtained in order to calculate the estimate of the orientation matrix

according to the MIMOSA method:

- обратная и союзная матрицы,where

- inverse and union matrices,

det N is the determinant of the identification matrix N.

The fulfillment of the condition of non-degeneracy of the identification matrix N is checked:

и определяют их знаки.According to formulas (39) and Tables 1-3, estimates of Euler angles are calculated

and determine their signs.

4. Control and normalizing operations are performed (pos. 4 in Fig. 1) according to complex algorithms for self-testing and combined autonomous diagnostics (CASKAD) (pos. 7 in Fig. 2):

Similarly perform control operations on the components of additional vectors (33).

The verification of the correctness of the calculation of estimates of the software orientation parameters is performed according to the algorithms of autonomous control and normalization (ACN) [17]:

Based on the results of performing DCA operations according to the CASCADE algorithms, in conclusion, operations are performed to correct and normalize the results of calculations in block pos.3 (Fig. 1) [17].

The practical implementation of the proposed method MIMOSA can be performed both on imported and domestic element base (table 4,5).

Numerical estimates by calculation show that for the implementation of a strapdown attitude control system (SOS) based on the proposed method with permissible errors in the orientation of software in space within 10'...20', it is sufficient to use blocks of vector sensors as part of the SSO, which have instrumental errors and resolutions no worse than threshold values:

which corresponds to the level of achievable indicators for existing (Table 4), and even more so for promising vector sensors.

The length of the MK bit grid of 24 bits, which is necessary to provide computational operations when processing information with guaranteed accuracy in solving the problem of autonomous orientation (with an allowable error and a resolution of at least 1"), suggests:

с помощью ТБМ с допустимой погрешностью

(с точностью до второго знака после запятой),- measurement of vector components

using TBM with an allowable error

(accurate to the second decimal place),

(с точностью до пятого знака после запятой),- measurement of the components of the vector n using TBA with an allowable error

(accurate to the fifth decimal place),

- calculation in MK of functions of Euler angles with a permissible error not exceeding 0.001% (with an accuracy of six decimal places).

For comparison, it should be pointed out that in modern digital flight and navigation systems, information is processed with a digit grid length of 16 ... 32 characters.

Determining the required frequency of updating information is associated with an assessment of the dynamic properties of the software on which it is proposed to implement the BSO in accordance with the proposed method. Numerical analysis shows that for the most dynamic channel of the roll (rotation) of the software, the frequency of updating information in the BSO must satisfy the condition:

частота

Для маломаневренных ПО эта частота обновления информации в БСО

может быть снижена на 1…2 порядка. Частота обновления информации в пилотажном

и навигационном

должны удовлетворять условию согласования:With an allowable error δγ = 1'' for highly maneuverable software

frequency

For low-maneuverable software, this frequency of updating information in the BSO

can be reduced by 1...2 orders of magnitude. The frequency of updating information in the flight

and navigational

must satisfy the agreement condition:

(от СНС) условие (55) выполняется с большим запасом.When the frequency of updating navigation information

(from SNS) condition (55) is satisfied with a large margin.

должна быть согласована с тактовой частотой

обработки приборной, геофизической и пилотажно-навигационной информации в МК:On the other hand, the step frequency of information in

must be matched to the clock frequency

processing of instrumental, geophysical and flight and navigation information in MC:

When choosing modern on-board computers (Table 4), condition (56) is fulfilled.

An important fact in favor of the proposed method of strapdown autonomous software orientation in space is the fact that this method does not impose any restrictions on the choice of the TBM installation site at the facility. In accordance with the requirements of the industry standard (OST 1 00374-80 "Magnetic heading sensors. Requirements for placement on airplanes and helicopters") in aviation, there are restrictions on the choice of installation location for magnetometric sensors on aircraft. Similar restrictions exist in the navy and rocket and space technology. Moreover, to reduce the level of magnetization of floating vehicles in the navy, the technology of demagnetization of ships and submarines is widely used.

In accordance with the algorithms for processing magnetometric information (41), the proposed MIMOSA method takes into account not only the magnetic and electromagnetic properties of the software, but also the assembly errors of the TBM and the errors of its installation at the facility.

In addition, in accordance with the algorithms of platformless information processing (37H39), (Tables 1-3)

- all restrictions on the conditions for performing spatial maneuvers of the software have been removed (i.e., the conditions for all-maneuverability and all-mode operation of the BSO are provided),

- no preliminary execution of the operations of the initial autonomous exhibition (NAV) is required.

For a BSO that implements MIMOSA algorithms, it is important to perform three modes of operation in 3 stages:

- mode (stage) of technological preparation,

- regular mode (stage) of work,

- mode (stage) of self-testing and self-diagnostics.

Structurally, the BSO that implements the MIMOSA method can be built according to one of three options:

- in the form of a single monoblock (module),

- in the form of a set of separate blocks,

- in a mixed version.

The BSO calculator can be implemented according to the circuit built into the design measuring module or as a separate computing unit.

A feature of the practical implementation of the proposed invention lies in the fact that the hardware of the system is selected based on the specific requirements associated with the type of object, the environment and the conditions for its use, and the achievement of the corresponding functions by the system is ensured by the replaceable universal software and algorithmic support. This means that the proposed method can be implemented both in existing BSOs and in planned and promising developments.

An analysis of domestic and foreign scientific and technical literature, and patent sources over the past 30 years shows that there is currently no alternative to the proposed invention, and the proposed method of strapdown autonomous software orientation itself has the necessary signs of novelty, relevance and prospects.

List of literature and patent sources

1. Matveev V.V., Raspopov V.Ya. Fundamentals of building strapdown inertial navigation systems / Under the general. ed. d.t.s. V.Ya. Raspopov. - St. Petersburg: State Scientific Center of the Russian Federation JSC "Concern" Central Research Institute "Elektropribor", 2009, -280 p.

2. Orientation and navigation of moving objects. Modern information technologies / Under the general. ed. B.S. Aleshina, K.K. Vereemenko, A.I. Chernomorsky. -M.: Fizmatlit, 2006. - 424 p.

3. Repnikov A.V., Sachkov G.P., Chernomorsky A.N. Gyroscopic systems: Proc. allowance for aviation. universities / Ed. d.t.s. A.V. Repnikov. -M.: Mashinostroenie, 1983. -319 p.

4. Rakhteenko E.R. Gyroscopic orientation systems. - M.: Mashinostroenie, 1989.-232 p.

5. Micromechanical sensors and systems. Practical results and development prospects / XII St. Petersburg International Conference on Integrated Navigation Systems - St. Petersburg: State Scientific Center of the Russian Federation OJSC Concern Central Research Institute Elektropribor, 2005, - P. 262-275.

6. Proskuryakov G.M., Plotnikov P.K. Geometry and kinematics of the spatial state of moving objects: textbook. allowance/Sarat.tech. un-t, Saratov, 2008. -155 p.

7. Shvedov A.P. Complexing of magnetometric and inertial orientation systems / A.P. Shvedov, Yu.V. Ivanov, D.M. Malyutin, R.V. Alaluev, M.G. Pogorelov//Handbook. Engineering Journal. Appendix No. 6, 2010 - From 15-19.

8. Manual of the World Geodetic System - 1984 (WGS-84) / - International Civil Aviation Organization IKAO, 2nd edition, 2002, DOC 9674.

9. International Geomagnetic Reference Field IGRF WMM-20, URL: // www.ngdc.noaa.gov/com (accessed 12/20/2021).

10. Silkin A.A. Synthesis and analysis of algorithms for determining the spatial orientation of an unmanned aerodynamic platform based on measurements of the Earth's magnetic field / dissertation. degree cand. tech. Sciences / Institute of Mechanical Engineering named after A.A. Blagonravov RAS. -M., 2002.

11. Pat RU No. 2503 810 IPC E21 B 47/22. The method of autonomous orientation of the inclinometer in the well, publ. 01/10/2014.

12. Binder Ya.I. Paderina T.V. Strapdown inertial measuring module: compassing and calibration on a movable base in conditions of limited angular displacements / Gyroscopy and navigation, No. 4 2003, P. 30-40.

13. Patent RU No. 2653967 C1 IPC G 01 21/00 Method for autonomous orientation of moving objects /authors: Proskuryakov G.M. et al./Patentee-FGBOU VO Sarat.gosud. tech. un-t im. Gagarina Yu.A. dated 06/20/2017, publ. 05/15/2018, Bull. No. 14.

14. Ignatiev A.A., Proskuryakov G.M. Heteromagnetometry: algorithms, techniques, calibration of magnetometer blocks. Saratov: Publishing House of Sarat.un-ta, 2014. -152 p.

15. Patent RU No. 2757828 IPC G05D 1/00; G 05 B23/00; G06F 11/00. A method for restoring vector information in information-measuring systems /authors: Proskuryakov G.M., Golovanov P.N., Pylsky V.A. tech. un-t im. Gagarina Yu.A. dated 12/15/2020, publ. 10/21/2021, Bull. No. 30.

16. Koryukin M.S. Construction of algorithms for the operation of a gyroscope-free aircraft orientation system integrated with SNS (materials of the VII conference of young scientists "Navigation and motion control" / Under the general editorship of Academician RAS V, G. Peshekhonov, - St. Petersburg: SSC RF JSC Concern Central Research Institute Elektropribor, 2006, -p.282-287.

17. Branets V.N. Lectures on the theory of strapdown inertial navigation control systems: Proc. allowance. -M.: MIPT, 2009. -304 p.

Claims (1)

A method for strapdown autonomous orientation of moving objects in near-Earth space, based on the formation of primary instrumental information about the apparent acceleration vector

and vector of the resulting magnetic field

according to the signals of pre-calibrated three-axis blocks of accelerometers and magnetometers, as well as on the subsequent processing of this information, taking into account the use of navigation information received from a satellite navigation system, in order to determine the orientation parameters of an object, characterized in that, first, based on the method of restoring vector information, the measured vectors

are corrected taking into account the results of previously performed technological calibrations and lead to the axes of the orthonormal basis m=XYZ associated with the object

then, based on the use of navigation information from the satellite navigation system, the components of the vectors of the Earth's gravity field are calculated

geomagnetic field

and apparent acceleration

reduced to the axes of the q basis, and finally, according to the vectors corrected and reduced to the m and q bases

determine the orientation parameters of the object using non-integral algorithms for strapdown processing of vector information.

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