RU2723976C1 - Method for determining angular orientation of ground vehicle - Google Patents

Abstract

FIELD: physics; machine building.SUBSTANCE: invention relates to gyroscopic instrument-making and can be used in ground vehicles for continuous determination of angular orientation (heading, roll, pitch) of moving vehicle. Method for determination of angular orientation of vehicle includes initial exhibition of stabilized platform (SP) of triaxial gyrostabilizer in plane of horizon and orientation in countries of light, control of SP signals proportional to angular speed of rotation of Earth and integrated information from accelerometers. During the parking at the initial control section, the system is tuned, during which the error constants of the initial angular display of the instrument coordinate system are determined in the reference coordinate system and angular velocity error. In the process of controlling the SP in each cycle by the digital computer system (DCS), using external information of the current values of the geographical coordinates of the vehicle, calculation of correction values of angular deviations of the instrument coordinate system from the reference coordinate system taking into account instability of errors of all elements of the control circuit in real time. Values of corrections obtained in each DCS cycle of the central coordinates are used to compensate for errors in the inertial navigation system and accurate determination of angular orientation of the vehicle by pitch, yaw and course taking into account information from angle sensors.EFFECT: technical result is reduced error of determination of angular orientation of ground vehicle in process of movement taking into account instability of errors of sensitive elements in real time scale.1 cl, 3 dwg

Description

The invention relates to gyroscopic instrumentation and can be used in land vehicles (TS) for the continuous determination of the angular orientation (course, roll, pitch) of a moving vehicle.

The following methods are known from the prior art for determining the angular orientation of a moving vehicle.

A method for generating navigation parameters and the vertical of a place, which consists in generating signals proportional to the corresponding projections of the apparent acceleration vector measured using accelerometers installed on each axis of the instrument trihedron associated with the gyro platform, generating control signals for the gyro platform, holding the gyro platform in the horizontal plane, and generating a vertical location and navigation parameters based on control signals proportional to the corresponding projections of the angular velocity vector of the instrument trihedron and taking into account the estimation of their errors by comparing the values of the same output parameters of various integration loops of the kinematic equations of the instrument trihedron generated on the basis of signals proportional to the sum of the corresponding projections of the angular velocity vector of the instrument trihedron and the corresponding additional signals, the magnitude and law of change of which are pre-set or set with the power of the device for generating navigation parameters, due to which circuit means provides a reduction in the influence of inertial system errors on the output navigation parameters and the vertical location. [1]

Inertial navigation method, including measuring signals from accelerometers, generating a reference coordinate system, calculating the output navigation parameters of the system, characterized in that the output parameters of the navigation system are calculated using the reference model, the corresponding input signals from accelerometers are calculated for the reference model in which the reading system is deployed coordinates at fixed angles relative to the reference coordinate system of the navigation system, calculate the signals from the accelerometers obtained by redesigning the signals from the accelerometers of the navigation system to the coordinate system deployed at the same fixed angles, then from the values of the calculated signals from the accelerometers for the reference model and signals from the accelerometers obtained by redesigning, determine the angular drift of the reference coordinate system of the navigation system and carry out the correction of the angular position of the reference coordinate system of the navigation system we. [2]

These methods have 2 main disadvantages that do not allow to provide the specified accuracy:

1. In the methods, the effect of various errors on the errors of the navigation system is determined and compensation is introduced based on their immutability. Real equipment has unstable errors and taking into account their changes in the process of vehicle movement is the main task of the developer of an autonomous navigation system or systems for generating angular orientation of the vehicle.

2. Real equipment generates output information with a high level of interference due to the presence of vibration and shock during vehicle movement. Continuous execution of calculations by the proposed methods in these conditions is impossible.

Closest to the proposed technical solution is the method described in [3]. The essence of the method is the formation, on the basis of general equations of errors, of simplified models describing the errors of the inertial navigation system (ANN), valid for various operating conditions (movement with small constant speeds υ≤500 km / h relative to the Earth, within 1 hour, 2- 2.5 hours, as well as accelerated movement of the object). Determination of errors in the navigation parameters of the ANN, based on the use of information from sensors external to it, and their assessment by wave estimation algorithms and limit transition algorithms, and algorithmic compensation for these errors of the ANN.

The application of the above methods allows us to solve both the direct problem of determining the navigation parameters, and the inverse - determining the angular orientation of the vehicle, with ANN errors. These methods are very time-consuming, have significant errors, and reliable values are determined with a large delay, which does not meet modern requirements for determining the angular orientation of the vehicle, which require the calculation of these parameters in the process of movement continuously and with a delay of no more than 0.06 seconds. The correction of errors in the navigation parameters of the ANN described in [3] is not carried out in real time.

The objective of the invention is to develop a method for determining the angular orientation of the vehicle with fewer errors in real time using external information of the current values of the geographical coordinates of latitude and longitude.

The problem is solved by the fact that the proposed method for determining the angular orientation of the vehicle, including the initial exhibition of the stabilized platform (SP) of the triaxial gyrostabilizer (TGS) in the horizontal plane and orientation to the countries of the world, control of the SP signals proportional to the angular velocity of the Earth and integrated information from accelerometers. During parking at the initial control section of the joint venture, the system is tuned, during which the error constants of the initial angular exhibition of the instrument coordinate system in the reference coordinate system and the angular velocity errors are determined. In the process of controlling a joint venture in each cycle by a digital computer complex (CVC), using external information of the current values of the geographical coordinates of the vehicle, the correction values of the angular deviations of the instrument coordinate system from the reference coordinate system are calculated taking into account the instability of the errors of all elements of the joint venture control circuit in real scale time. The correction values obtained in each CVC cycle are used to compensate for errors in the inertial navigation system and to accurately determine the angular orientation of the vehicle by pitch, yaw and heading, taking into account information from angle sensors.

The errors of the ANN, implemented by the instrument trihedral of the gyro platform, oriented to the countries of the world and the local vertical, under the conditions of stability of their own drifts of gyro blocks and using external information of the current values of the latitude and longitude of the moving vehicle, are compensated by the generated corrections, taking into account the instability of the errors of all elements of the gyro platform control scheme in real scale time, which are due to the control features, in the feedback mode according to information from accelerometers [4], they lead to angular errors in three axes, and therefore to a change in the projection of gravity acceleration (g) on the measuring axes of the accelerometers.

In FIG. 1 shows the structural diagram of the TGS, for which the proposed method is applied, where:

X _P Y _P Z _P - instrument coordinate system (UCS) associated with the joint venture;

X _K Y _K Z _K is the coordinate system associated with the device body and the vehicle, due to the tight connection of the device and the vehicle;

B, P, T - axis of rotation, yaw and pitch, passing through the frames of the gimbal;

GB X, GB Y, GB Z - two-stage float integrating gyroscopes located along the axes X _P , Y _P and Z _P, respectively;

X, Z - accelerometers located along the axes X _P and Z _P respectively;

DK V, DK R, DK T - command sensors located along the axes B, P and T of the gimbal, respectively;

DU V, DU R, DU T - angle sensors located along the axes B, P and T, respectively.

TGS contains a joint venture located in a three-axis gimbal, with angle sensors (DU) and command sensors (DK) installed on each of its axes. Two accelerometers and three two-stage float integrating gyroscopes are installed at the joint venture, which form the right rectangular coordinate system parallel to the UCS axes. Gyroscopes on the precession axes have moment sensors (DM) and precession angle sensors (DUP), which are included in the TGS stabilization system and the reduction system. The formation of the control signal SP is implemented by the CVC.

In FIG. 2 shows the relationship of UCS (X _P Y _P Z _P ) and the reference coordinate system (CSC) (X _O Y _O Z _O ) of a semi-analytical ANN, where:

X _O - the horizontal axis of the USC, directed to the North;

Y _O - axis directed along the local vertical;

Z _O - complements the coordinate system to the right;

ω _X , ω _Y , ω _Z - the projection of the angular velocity of the joint venture relative to the axes X _P , Y _P , Z _P ;

α _X , α _Y , α _Z - mismatch angles of UCS and USC along the axes X, Y, Z.

In FIG. 3 is a diagram of a device for implementing a method for determining the angular orientation of a land vehicle, which includes a TGS (DU V, DU R, DU T, DM GB X, DM GB Y, DM GB Z, accelerometers X and Y), an external navigation sensor ( GLONASS, GPS, etc.) and CVC. The CVC comprises a stabilized platform control signal generation unit, a vehicle relative speed calculation unit, a calculation unit for the tuning constants and correction values of the angular deviations of the orientation of the instrument coordinate system from the reference coordinate system, and a vehicle angular orientation calculation unit. β, Ψ, K are the angles of deviation of the coordinate system associated with the device’s body from the OSK in pitch, yaw and heading, respectively, and are identical to the angles of deviation of the vehicle from the OSK, due to the tight connection of the device and the vehicle.

The SP placed in the horizontal plane and oriented to the countries of the world is controlled by the control signals generated by the CVC in the CVC and proportional to the angular velocity of the Earth’s rotation and integrated information from X and Z accelerometers. The SP should be deployed relative to the inertial coordinate system (ISK) with angular velocities:

,

,

- угловые скорости вращения СП относительно ИСК;where:

,

,

- angular velocity of rotation of the joint venture relative to the ISK;

Ω is the angular velocity of the Earth;

B, L -information of the current values of the geographical coordinates of latitude and longitude of the OSK coming from an external navigation sensor (GLONASS, GPS, etc.);

V _X , V _Z - projection of the relative (ground) speed of the vehicle on the X and Z axis of the OSK, calculated according to the information of the accelerometers X and Z;

R _N and R _E - surface curvature at the current point on the Krasovsky ellipsoid in the North-South and West-East directions in the planes of the sections of the ellipsoid passing through the Y _O axis.

In the process of managing the joint venture, in each cycle in the CVC are calculated:

1. sin B, cos B - values of the functions of the sine and cosine of latitude;

2. ΔВ, ΔL - full increments of the geographical coordinates of latitude and longitude;

3. V _X , V _Z - projection of the ground speed of the vehicle;

4. R _N and R _E - according to information of the current latitude;

- ускорение Кориолиса.five.

- Coriolis acceleration.

The projections of the relative velocity of the vehicle on the X _O and Z _O axis (V _X , V _Z ) are determined by integrating information from the corresponding accelerometers about the apparent acceleration taking into account the Coriolis acceleration along the Z axis of the USC:

The Coriolis acceleration is combined with the apparent acceleration during the movement of the vehicle in the northern hemisphere, since it is directed to the left of the vehicle velocity vector and practically does not affect the motion parameters, but is perceived by the accelerometer located along the Z axis of the joint venture.

The calculation of ANN errors takes into account the error constants of the initial orientation along the angles and angular velocities along 3 axes, determined over a short time interval during the vehicle’s parking, with the current values Vx (z) and ΣVx (z) calculated from information from accelerometers, as well as external information on the current values of latitude and longitude, in conditions of stability of their own drifts of gyro blocks.

With perfect control, that is, in the absence of any errors in the equipment, the relative angular velocity of the instrument coordinate system in the reference coordinate system will be zero and the initial coincidence of the UCS and USC will be preserved.

The initial exhibition usually has errors in angles and angular velocities. Angular errors cause disturbances in the control system of the joint venture in the form of projections of the acceleration of gravity (g) on the X and Z axes of the UCS and projections of the angular velocity of the Earth's rotation (Ω) on all the axes of the UCS.

Errors of the initial angular velocity are maintained throughout the entire navigation time.

Denoting the mismatch angles of UCS and USC as α _X , α _Z and α _Y , corresponding to the angular deviations of the measuring axes of the X and Z accelerometers from the USC and the Y-axis axis angle sensor _{П П} СП, and the angular velocity errors as δω _X , δω _Y and δω _Z , we can write the values of the relative angular velocities ω _X , ω _Y and ω _Z , respectively, to the axes SP X _P , Y _P , Z _P , according to the diagram shown in FIG. 2:

где Т_ц - время цикла ЦВК,Given that

where T _c - the time of the CVC cycle,

i is the index of the current operand, (i-1) is the index of the previous operand, and bringing it to a form convenient for integration on the CVC, we obtain a mathematical model of errors that determine the position of the UCS relative to the USC during parking:

where: Vx (z) are the projections of the relative velocity of the vehicle on the X and Z axis of the OSK, calculated according to information from the accelerometers X and Z during the control of the joint venture in the parking lot, in each CVC cycle;

- константы погрешностей начальной угловой выставки ПСК в ОСК.

- error constants of the initial PSK corner exhibition in USC.

, можно записать в виде:Having

, can be written as:

Integrating (4), substituting into the right-hand side of (5) and, taking into account the change in latitude and longitude under traffic conditions, we obtain the correction values of the angular deviations of the orientation of the UCS from the USC

where: index P - correction value of the angular deviations of the UCS from the OSK;

ΔL _i , ΔB _i - current (complete) changes in the geographical coordinates of the latitude and longitude of a moving vehicle.

δω_Z, δω_Х и δω_Y, измеряемые при настройке, во время управления СП сигналами, пропорциональными угловой скорости вращения Земли и интегрированной информации с акселерометров X, Z в первые несколько секунд работы, используя текущие значения широты и долготы, поступающие от внешнего навигационного датчика, а также текущие значения

V_X(Z)i, вычисляемые в каждом цикле ЦВК во время управления СП, с учетом нестабильности погрешностей всех элементов схемы управления СП в реальном масштабе времени.Formulas (6) allow us to calculate the correction values of the angular deviations of the orientation of the UCS from the OSK in the process of moving the vehicle using the constants

δω _Z , δω _X and δω _Y , measured during tuning, while controlling SP signals proportional to the angular velocity of the Earth’s rotation and integrated information from X, Z accelerometers in the first few seconds of operation, using the current latitude and longitude values received from an external navigation sensor as well as current values

V _{X (Z) i} , calculated in each cycle of the CVC during the control of the joint venture, taking into account the instability of the errors of all elements of the control circuit of the joint venture in real time.

The instability of the errors of the sensitive elements and the gyro platform control path included in the system, as a rule, is caused by a change in the values of V _Xi and V _Zi , which are calculated using the CVC and taken into account in the correction formulas (6) in real time.

The correction values obtained in each CVC cycle are used to compensate for ANN errors.

The angles β, Ψ, K are calculated taking into account the information of the angle sensors located on the axes B, P and T of the cardan suspension of the device.

During the movement of the vehicle, the values of the projections of the relative velocities (Vx, Vz) and their integrals are filtered parameters that are calculated continuously and also allow you to continuously determine the corrections of the angular deviations of the instrumental UCS trihedron from the reference OSK trihedron.

The proposed method provides for the following operations:

1. The initial exhibition of the joint venture in the plane of the horizon and orientation to the countries of the world;

2. Management of SP signals proportional to the angular velocity of the Earth’s rotation and integrated information from X, Z accelerometers using external information of the current values of the geographical coordinates of the latitude of the TS;

и погрешностей угловых скоростей δω_Y, δω_Z, δω_Х;3. System configuration at the initial short-term joint venture control section during parking, during which the error constants of the initial corner exhibition of the CPM in the USC are determined

and angular velocity errors δω _Y , δω _Z , δω _X ;

4. The development of correction values of angular deviations that determine the position of the UCS relative to the OSK, taking into account the instability of the errors of all elements of the gyro platform control circuit in real time;

5. Compensation of ANN errors;

6. Determination of the angular orientation of the vehicle, taking into account information from the angle sensors of the cardan suspension of the device.

Thus, a method is proposed that is used to determine the angular orientation (heading, roll, pitch) of a land vehicle, including the initial exhibition of SP TGS in the horizontal plane and orientation to the countries of the world, control of SP signals proportional to the angular velocity of the Earth’s rotation and integrated information from accelerometers . During parking at the initial control section of the joint venture, the system is tuned, during which the error constants of the initial angular exhibition of the instrument coordinate system in the reference coordinate system and the angular velocity errors are determined. In the process of controlling a joint venture in each CVC cycle, using the external information of the current values of the geographical coordinates of the vehicle, the correction values of the angular deviations of the instrument coordinate system from the reference coordinate system are calculated taking into account the instability of errors of all elements of the joint venture control circuit in real time. The correction values obtained in each CVC cycle are used to compensate for errors in the inertial navigation system and to accurately determine the angular orientation of the vehicle by pitch, yaw and heading, taking into account information from angle sensors.

The technical result of the application of the proposed method is to reduce the error in determining the angular orientation (heading, roll, pitch) of a ground vehicle during movement, taking into account the instability of errors in the sensitive elements and the gyro platform control path in real time, which, according to the control features in the information feedback mode signals from accelerometers are reduced to angular errors along three axes, and therefore to a change in the magnitude of the projection of the acceleration of gravity on the measuring axes of the accelerometers.

List of references:

1. Patent RU No. 2098765 "Method for the development of navigation parameters and vertical location" (09/30/1994);

2. Patent RU No. 2107897 "Method of inertial navigation" (04/10/1995);

3. O.S. Salychev, Wave description of perturbations in problems of estimating errors of inertial navigation systems, - Moscow. Engineering, - 1992, - p. 128-141;

4. Inertial navigation systems of marine objects, D.P. Lukyanov, A.V. Mochalov, A.A. Odintsov, I.B. Weissgant, - Leningrad. Shipbuilding, - 1989, 184 p.

Claims (1)

A method for determining the angular orientation of a land vehicle, including the initial exhibition of a stabilized platform (SP) of a triaxial gyrostabilizer in the horizontal plane and orientation to the countries of the world, control of SP signals proportional to the angular velocity of rotation of the Earth and integrated information from accelerometers, error compensation of an inertial navigation system, characterized in that during parking at the initial control section of the joint venture, the system is set up, during which the error constants of the initial angular exhibition of the instrument coordinate system in the reference coordinate system and the angular velocity error are determined, in the control process of the joint venture in each cycle by a digital computer complex (CVC), with using external information of the current values of the vehicle’s geographical coordinates, the correction values of the angular deviations of the instrument coordinate system from the reference coordinate system are calculated taking into account the instability of the errors values of all elements of the SP control circuit in real time, the correction values obtained in each cycle of the CVC are used to compensate for errors in the inertial navigation system and accurately determine the angular orientation of the vehicle by pitch, yaw and heading, taking into account information from angle sensors.

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