UA100760U - HYROAXELEROMETRIC METHOD OF DETERMINATION OF ANGLE ORIENTATION PARAMETERS - Google Patents

Abstract

Gyro-accelerometric method of determining the parameters of angular orientation involves measuring the projections of absolute linear acceleration and measuring the projections of the earth velocity vector, components of coriolis and relative acceleration. The values of roll and pitch are calculated by accelerometer information having a high-frequency error, and then processed according to the compensation scheme.

Description

The utility model belongs to the field of navigation technology and can be used in the design of integrated inertial-satellite navigation systems (INS) for various vehicles, including unmanned aerial systems (UAS).

A known method of determining angular orientation parameters according to (1), based on the use of signals from the accelerometer unit and gyroscopic angular velocity sensors, is as follows. They calculate the matrix of guiding cosines between the bound and navigation coordinate systems, compensate for accelerometer errors due to accounting for the rotation of the bound system, recalculate the readings of the accelerometers from the bound to the navigation coordinate system and integrate them to calculate current speeds and coordinate increments. At the same time, various modes of object movement are taken into account, which are characterized by roll parameters, course derivative and acceleration in the horizon plane.

Further, these parameters are used to calculate the gain coefficients of systems that implement individual control laws in parallel to the calculated matrices of guide cosines between the bound and navigation coordinate systems based on the same readings of accelerometers and angular velocity sensors. For each computational matrix of guiding cosines, their own navigation parameters are determined, which have a different frequency of errors. Errors in the calculation of each of the matrices also have a different frequency spectrum depending on the media movement modes. Navigation parameters for each computational matrix of guiding cosines are fed to the inputs of the filter, which forms an optimal combination of navigation solutions depending on the frequency range of their errors, as well as on movement parameters. The disadvantage of the proposed method is the need to take into account different modes of movement.

There is a known method of determining the angular orientation parameters I|2| consists in improving the inertial-satellite system with the combined use of satellite data by replacing expensive high-precision inertial sensors with more "rough" and cheap ones based on

MEMb5B technology, as well as the introduction of an additional magnetometer block and a height measurement block containing a barometric and ultrasonic altimeter. Its disadvantage is the use of a large amount of satellite navigation system (SNA) information, which may not be available in a radio silence zone or when the satellite signal is intentionally blocked.

There is a known method of determining navigation parameters by |IZ| includes an inertial system

From the orientation (CO) on "rough" sensitive elements, which is connected to the computer platform and has three accelerometers and three angular velocity sensors located along three orthogonal axes of ISO. Orientation angles are calculated by calculating the matrix of guiding cosines between the bound and navigation coordinate systems, perform compensation for the errors of the acceleration signals of the accelerometers, perform the recalculation of accelerations from the bound coordinate system to the navigation system, and determine the current speeds and coordinate increments. The disadvantage is that errors in determining orientation are uniquely determined by the accuracy of angular velocity sensors (AVRs) and accelerometers, while errors in determining coordinates grow over time in proportion to the speed of AVR drift. Therefore, after some time of autonomous operation (it depends on the accuracy of the sensitive elements), the navigation system calculated on board will differ from the true navigation system by large angles, which actually leads to the failure of the navigation method. A limitation of this traditional method is that the errors of the inertial system are inseparable from the useful signal (ie, the true navigation parameters). This conclusion is based on the fact that the errors of the inertial system have a low-frequency character, the so-called Schuler oscillations, which are inseparable from the real movements of the carrier on which the system is installed.

The task of the useful model is to increase the accuracy of determining the navigation parameters by correcting the angular orientation parameters by compensating for errors that appear due to the drift of gyroscopic angular velocity sensors.

The problem is solved by the fact that the gyroaccelerometric method of determining the parameters of the angular orientation includes measuring the projections of the absolute linear acceleration using accelerometers, measuring the projections of the earth velocity vector and the components of the Coriolis and relative acceleration, using gyroscopic sensors of angular velocities, according to the useful model, the roll and pitch values are calculated according to the information of the accelerometers, which has a high-frequency error, is then processed according to the compensation scheme.

If the only force acting on the object is the force of Earth's gravity, then. pr rerometer, measuring the projection of the gravity vector on its own axis of sensitivity - Za po z is used as an inclusion ADuation of the static angle of inclination of the accelerometer.

In practice, in addition to the force of gravity, other forces act on a moving object, caused by accelerations, rotations, shaking, etc. In particular, in flight, the Coriolis acceleration o h transfer acceleration and the acceleration of the earth's gravity. Then acceleration

A, measured by an accelerometer, looks like this:

Am no go)hM, oh shh B) obi

Usually, the transferable acceleration caused by the rotation of the Earth (ох(охв)|) is vector summed up with the acceleration of the earth's gravitational forces Чо (8), forming the acceleration of the force of gravity d- do(8)-ох(ох В).

Then the equations of the imaginary accelerations of the object's center of mass, measured by the accelerometer, take the form

A - (M) n(ezhgo)x M, -9. (WITH

In the formulas given above, MG is the relative speed vector of the LA; AK - vector characterizing the current location of the object in the selected coordinate system (SC); 9 is the angular speed that occurs when flying over the spherical surface of the Earth, which, in turn, rotates with an angular speed of 9.

In the algorithms of the operating modes of the platform-less inertial navigation system (BINS), in order to obtain the value of the earth velocity vector by integrating the signals of the accelerometers projected on the axis of the rectangular geographic SK OI HV, it is necessary to subtract the components of the Coriolis acceleration projections from these projections (2, an, c) and the components of the acceleration projections of the force of gravity. Then the projections of the vector of the earth's velocity on the axis of the SC ОИ НВ are obtained by integrating the equation в "Men, -Mnov, )- 9. ov Mn-an -M ov, -Mver) on.

Mv - av -IMnei, -M on, ) Ov ov -ov ho ots -Fotsn ho o o -F Shsch620 and p. where B; Wu V.N" Nu N.I; Gu o. components of projections

Mvono - Mo M ov - Mvo Mne; - What can you do? veins, and in.) | STV, V c) | nt d ne) - projections of Coriolis acceleration;

F F F. . pe in, ; Well; in. projections of the angular speed of rotation of the navigation SC OY LV, which occurs when flying over the spherical surface of the Earth; Ов - Озсо5В оон Z озвыВ 0-0, projections of the angular speed of rotation of the Earth ОЗ on the axis of the navigation SK ОИ НВ; MV. M, Mn. projections of the velocity vector on the axis of the SC ОИ НВ; Ус, Ув, 9Ун - projections of the acceleration of the force of gravity, which, with small k - - values of the height (NetObkm), keeping only terms of the order of smallness 10-, are calculated according to the formulas: 9 У Ов - (9) ре дн - -ой т52884.1073 вип "vit-inium c) and i

B - latitude; H - flight height; 9. acceleration of the force of gravity at the equator; C is the semi-major axis of the Earth's ellipsoid; Y is the eccentricity of the Earth's ellipsoid.

When applying the accelerometric method of determining the angular orientation parameters, a similar approach is used. From (zo. accelerometers (1) subtract the projections of the components of the relative 7/3 and Coriolis Fo k20)x M, the accelerations of the center of mass on the axis of the connected SC, leaving only the components of the acceleration of the force of gravity. --9

According to the magnitudes of these acceleration projections of gravity forces, undisturbed by other forces, roll and pitch angles are determined by inclinometer algorithms.

The components of Coriolis and relative acceleration in ISSN are calculated either by navigation parameters estimated using the compensation method. The obtained parameters of the angular orientation are subjected to additional processing using information from the DKSh, which are part of the BINS.

The structural diagram of the gyro-accelerometer angular orientation meter is presented in the drawing.

Here, according to ISSN data on the components of the Earth's velocity vector and the components of Coriolis and relative acceleration, their projections on the axis of the connected SC are calculated. The obtained components are subtracted from the readings of the horizontal accelerometers, and based on the information about the undisturbed components of the acceleration of the force of gravity, using the matrix of directional cosines and the current value of the acceleration of the force of gravity, which are calculated according to the BINS algorithms, the current values of roll and pitch angles are calculated.

Roll and pitch values calculated from accelerometers have a high-frequency error (sensor noise), so this information is subjected to additional processing using a compensation scheme. At the same time, BINS readings with a low-frequency variable error and VGA readings with a high-frequency constant error are integrated. The obtained estimates are used to correct the angular orientation parameters, which are calculated according to BINS algorithms.

The pro-accelerometric method of measuring the angular orientation parameters is considered in the two-component BINS work algorithms, which describe only the longitudinal movement of the UAV flying along the equator.

The kinematics of the rotary motion of the aircraft by the pitch angle in the algorithms of such BINS

I describe as follows:

Uyut ovi U vo (o, still 3/, 0 and the kinematics of translational movement of the center of mass - movement in the vertical plane is described by the equation:

In ShN cor ul cor Kg -

Mn-an-an 78, M o -a -Z2a: GAM /Az.

Oz -7.27-1071/sec, Vz - 6378388М, where . y h an -akhvipo na/uso59 a; -akhsov95 -au vip9, (2) akst - -MtsiY 120). huh? - -M I -gov) - . . . . . 7 and au.

The input information for the BSHS are the signals of the inertial sensors of the ХХ, which with . yes . . . . . taking into account their errors (dog, lah, U), containing deterministic and white noise components, are described by the following equations: 02 all schools -(; kovi) do, (3) ah -ah. 98 and P9; z(vkorvipv -akorvipv; ) lah (4) and bark; .. aKOore; and au -au 9; сО55, «iv zpU; -and); vepv;)klau (c) . . -F

Here it is taken into account that the DKSh, in addition to the angular velocity en, which characterizes the BAS maneuver, . : ; with and And:

Zo also measures the angular velocity of the Earth's rotation and the angular velocity "!, due to the flyby of the UAS of the spherical Earth (the index "i" indicates that these are true, not calculated values).

Similarly, it is taken into account that accelerometers, in addition to the accelerations en, Ukan, which characterize the maneuver, measure the components of the Coriolis acceleration, as well as the components of the acceleration of the force of gravity.

To implement the gyroaccelerometric method of measuring the pitch angle, the calculated components of the Coriolis acceleration an'vipe - akRsov3 are subtracted from the readings of the longitudinal accelerometer ah. . ah ( ), as well as the calculated longitudinal accelerations of the center of mass of the BAS man caused by the control influences. Then the remaining signal of the longitudinal accelerometer contains only the projection of the gravity vector above its own De of the puffiness, as well as the deterministic and white-noise component of the error of this sensor x in Uzpolvtvah.

The components of the Coriolis acceleration are calculated according to formulas (2), using the estimated information about the components of the earth velocity vector (Un U) and the rate of change of longitude G., and

. . . o, also the known value of the angular speed of rotation of the Earth - To redesign these components on the axis of the connected SC, the corrected (gyroaccelerometric) value of the pitch angle a is used.

Skladovu, Khnan. calculated by the formula cor ; ag-a nau zp , kor, kor ah. КВЗБББЖЖЖ-- 2 Ж 2 5 - 9dapZ-iar'vpe-a| со595 man со59 I

Here, the components of the Coriolis acceleration are also calculated using the estimated information and the corrected value of the pitch angle. When projecting the acceleration of the center of mass of the BAS onto the longitudinal axis of the connected SC, the component of the normal acceleration U is subtracted from it and the previously excluded component of the Coriolis act 9-2 acceleration is restored. The acceleration of the force of gravity at the equator - 7 is set equal to 9.8 m/sec.

F

The estimated value of the horizontal component of the acceleration of the center of mass is obtained by integrating the BINS information and the differentiated signal of M. SHO. When differentiating a noisy radio-technical signal, SNS performs the usual filtering procedures for such signals.

According to the information of AH, the current value of the pitch angle is calculated - the accelerometric pitch angle. ja - agswip (Ah / 9).

The difference between the current value of the pitch angle, which is calculated according to BINS algorithms, and the accelerometric pitch angle forms a signal that corrects the reading of the DKSh (the deterministic component of the sensor error is written off).

Kk

AF, -|Kou-225- (8-5

More | sha Kg (in- you) . (6)

The result of such correction is the corrected (gyroaccelerometric) pitch angle Z,

Similarly, the value of the corrected (gyroaccelerometric) roll angle is calculated.

Sources of information: 1. Patent of the Russian Federation Mo 2348903 Method of determining navigation parameters using a platformless inertial navigation system, - 2009. 2. Patent of Ukraine Mo 79932 Small-sized inertial-satellite integrated navigation system, - 2013.

Zo 3. US Patent Mo 5422817 5igardoult ipegiia! pamidayop 5uziet iv5ipd podp ogaeg soggesiop, -

Claims (1)

USEFUL MODEL FORMULA Gyroaccelerometric method of determining angular orientation parameters, which includes measurement of projections of absolute linear acceleration using accelerometers and measurement of projections of the earth velocity vector and components of Coriolis and relative acceleration using gyroscopic sensors of angular velocities, which differs in that roll and pitch values are calculated from information of accelerometers, which has a high-frequency error, is then processed by a compensation scheme. "val Va B IH hodo dit mna shkny ZY OY t. lyut ik ET om VOMU Blok Essen pen o i Kn i V nin Mn SN I ak i poshko E MONE i N KKU E Jh bi N SO BAKI UBYNM I wa oooooossssssnnnia and with |yaV osv shcha ish an ud ; i і Z is N PEV KOHZ a VKM Kon meto N ike oo sh I N SHY EMK KeKAETH FROM photo. YES N: i Y iy Zhe ek I di shi zhk Ku nn nn ukkkkeyuyuyuyuyutu i N i UMH ooonyaya nn for adayayandianannn DIV MNK Motya M. H. - why yy Z gZ se I EK Ch VK KT N VK, I Her B with 1 in t also RO II A B V; kkkkkk sssr slia and E MMK TEN and PIVVSTEOSYAI I UK Demo oh NOT TY I ET TOO ev