RU2251078C1 - Method of determining navigation parameters and vertical of site - Google Patents

Abstract

FIELD: navigation.

SUBSTANCE: method comprises processing the signals from the gyroscope or pickups of absolute angular velocity. The gyroscopic platform controls the signals, which include the signals proportional to the components of the virtual acceleration generated by accelerometers, keeping the gyroscopic platform at a given angle with respect to the horizontal plane. The outer axis of the double-axle gimbal suspension is perpendicular to the base plane. The base is made of a platform stabilized in the horizontal plane.

EFFECT: enhanced reliability of determining.

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Description

The invention relates to gyroscopic instrumentation and can be used to provide navigation of marine, air and ground objects.

There is a method of generating navigation parameters and vertical location [1].

This method includes measuring the components of apparent acceleration using accelerometers, generating gyro platform control signals in the gimbal, working out the generated signals using a gyroscope, determining navigation parameters and the vertical location.

The disadvantage of this method is the limited possibility of dynamic and accuracy characteristics, design constructs.

The aim of the invention is to improve the accuracy and expansion of design capabilities.

The goal is achieved by the fact that the gyro platform is controlled by signals containing signals proportional to the apparent acceleration components generated by accelerometers, while the gyro platform control signals are formed in such a way as to provide a predetermined angle of inclination of the gyro platform relative to the horizon plane in the plane of the compass meridian, and to ensure direct reading of the course value object, the outer axis of the gimbal is installed perpendicular to the plane of the base, which I use a stabilized platform in the horizontal plane.

We illustrate the proposed method in the following examples. In the drawings 1 and 2 presents a functional diagram of a gyroscopic navigation system, where the following notation:

1 - sensory element (SE) - gyro-stabilized platform in a gimbal, the outer axis of which is directed perpendicular to the plane of the base;

2 - control unit gyro platform and the development of navigation parameters;

3 - control unit stabilization engines;

4 - three-stage gyroscope;

5, 6 - moment sensors of the gyroscope;

7, 8 - gyro angle sensors;

9, 10 - accelerometers;

11, 11 ', 12 - stabilization engines in the horizon;

13 - object heading sensor;

14 - stabilized in the horizon plane platform.

Example pic. 2 differs from the example in Fig. 1 by the presence of an additional degree of freedom around the ON axis, and, accordingly, by an additional stabilization engine 11 '.

The gyroscopic navigation system contains a gyro-stabilized platform 1, a gyro platform control unit and generating navigation parameters 2, on the gyro platform 1 there is a three-stage gyroscope 4 with moment sensors 5, 6 and angle sensors 7, 8, two accelerometers 9 and 10, axes whose sensitivities are orthogonal and are in the plane of the gyro platform 1, the outputs of the accelerometers 9, 10 are connected to the control unit of the gyro platform and generate output parameters 2, the outputs of which are connected to the moment sensors of the gyroscope 5, 6, the inputs of the unit board stabilization engines 3 are connected to the outputs of the angle sensors 7, 8 of the gyroscope 4, the outputs of the control unit of stabilization engines 3 are connected to the corresponding stabilization motors.

Gyroscopic navigation system operates as follows: gyro platform 1 using stabilization engines according to the error signals of the angle sensors of the gyroscope 7, 8 is always kept in the same plane with the casing of the gyroscope 4. The casing of the gyroscope 4 together with the gyro-stabilized platform 1 is brought into a position inclined relative to the plane the horizon at a predetermined angle and is held in this position with the help of moments superimposed through the moment sensors of the gyroscope 5, 6 according to the signals generated in the control unit gyro platform 2. With the appropriate choice of control signals of the gyro platform, including signals proportional to the apparent acceleration components generated by accelerometers, the inclination angle of the gyro platform (speed deviation value) can be related to the horizontal component of the absolute angular velocity of the object by the ratio:

where α is the angle of inclination of the gyro platform (value of speed deviation);

- горизонтальная составляющая абсолютной угловой скорости объекта;

- the horizontal component of the absolute angular velocity of the object;

R is the radius of the Earth;

ω _o - Schuler frequency;

n is the coefficient of proportionality.

.The values of the velocity deviation of the gyro platform indicate that the perpendicular to the plane of the gyro platform will always tend to be installed in the plane of the compass meridian, the direction of which is determined by the vector

.

The value of the coefficient η is chosen to be greater than unity in order to increase the guiding force of the gyroscope and provide a given angle of inclination of the gyro platform. Stabilized in the horizon plane platform 14 serves as the basis for the installation of a sensitive element (SE).

Platform 14 may be: a) a platform with indirect stabilization, for example, from an inertial system; b) the gyro platform of the inertial system; c) a gyro platform in a biaxial gimbal, for example, with a triaxial gyroscope, which provides stabilization along two horizontal axes, and accelerometers.

Measuring the angle between the plane of the CE platform and the plane of the horizontal platform, determine the instrumental value of the angle α _pr and thereby find the instrumental value of the horizontal component of the absolute angular velocity of the object

The angle α _pr can also be found using the readings of the accelerometer of the SE and the readings of the accelerometer of the inertial system, ensuring the position of the horizontal platform.

. Тогда проекции абсолютной угловой скорости трехгранника ENξ на его оси будут O;

, r₁. Проекции ускорения вершины трехгранника ЕNξ на его оси суть

; (r; V); g, где g - ускорение силы тяжести, r₁ - вертикальная составляющая абсолютной угловой скорости.As the initial coordinate system, we choose the accompanying Darboux trihedron ENξ, oriented by the OM axis along the horizontal component of the absolute angular velocity

. Then the projections of the absolute angular velocity of the trihedron ENξ on its axis will be O;

, r ₁ . The projections of the acceleration of the vertex of the trihedron ENξ on its axis are

; (r; V); g, where g is the acceleration of gravity, r ₁ is the vertical component of the absolute angular velocity.

With the gyro platform we associate the right coordinate system E ₁ N ₁ ξ ₁ . The axis Oξ _{1 is} perpendicular to the plane of the gyro platform. The coordinate system E ₁ N ₁ ξ ₁ will be obtained by turning around the Oξ axis by the angle ΔK, then by rotating around the auxiliary axis OE ₁ by the angle α and turning around the axis Oξ ₁ by the angle ΔKCosα, where ΔK is the error in generating the object's course.

For example (figure 2) also at an angle β around the axis ON ₁ .

The projections of the absolute angular velocity of the trihedron E ₁ N ₁ ξ ₁ on its axis OE ₁ and ON ₁ will be:

The projections of the acceleration of the vertex of the trihedron E ₁ N ₁ ξ ₁ on the axis OE ₁ and ON ₁ will be

+(r₁VCosα+gSinα)ΔKCosα+(r₁VSinα-gCosα)βW _E1 =

+ (r ₁ VCosα + gSinα) ΔKCosα + (r ₁ VSinα-gCosα) β

W _N1 = gSinα + r ₁ VCosα; Wξ ₁ = gCosα-r ₁ VSinα

For example (FIG. 1) β = ΔKSinα

W _E1 W _N1 Wξ ₁ - are measured by the corresponding accelerometers of the SE.

An accelerometer measuring Wξ _{1 is} not shown in the drawing.

To provide an invariant value of velocity deviation, for example,

The control signals in the coordinate system E ₁ N ₁ ξ ₁ can take the form, for example:

1) To generate the control signals for the _{gyro-platform CE} Ω _E1

или

or

2) To generate control signals for the _{gyro-platform CE} Ω _N1

или

or

or

The acceleration component along the ON axis can be obtained as:

(r ₁ V) _pr = W _N1 Cosα _pr -Wξ ₁ Sinα _pr

The equations of motion of the gyro-platform of the SE are determined by the following relations:

Ω _E1 = Ω _E1adr Ω _N1 = Ω _N1adr see (1), (2), (3).

.The inertial system that ensures the stabilization of the SE in the horizon, using the horizontal components of the absolute angular velocity of the Darboux trihedron, can determine the compass heading of the object Kies and the value of the horizontal component of the absolute angular velocity

.

According to the readings of accelerometers, the inertial system can determine the projection of the acceleration of the vertex of the Darboux trihedron ENξ on its axis OE and ON

W_Nkc=(r₁V)_nc W _EnC =

W _Nkc = (r ₁ V) _nc

The indicated information together with the information of the same name generated by the SE can be used both for controlling the SE and for controlling the inertial system and its gyro platform. At the same time, using the signals of the difference of the same information, they provide asymptotic stability of both the SE and the inertial system, as well as the assessment of their instrumental errors.

It should be noted that the same effect can be obtained when using the CE in the gyro platform instead of the three-stage gyroscope, two absolute angular velocity sensors (TLS).

In this case, the stabilization engines 11, 12 for the layout (figure 1) and 11, 11 'for the layout (figure 2) will perform the functions of tracking engines and work out the equilibrium position of the SE platform, characterized by the expression

and the direction when the perpendicular to the plane of the SE platform will be in the plane of the compass meridian.

The engine control signals in this case will be

where F ₁ and F ₂ - transfer functions;

Ω _E1 Ω _N1 - TLS signals, see (1);

Ω _E1adr Ω _N1adr - control signals see (2), (3);

Here, the conditions Ω _E1 = Ω _Eupr , Ω _N1 = Ω _N1upr will also be satisfied.

The specified method can be implemented in a strap-down ANN.

Sources of information:

[1] V.A. Belenky - Russian Federation Patent No. 2000544.

Claims (1)

A method for generating navigation parameters and elevation vertical, including measuring apparent acceleration components using accelerometers, generating gyro platform control signals, processing generated signals using a gyroscope or absolute angular velocity sensors, determining navigation parameters and elevation vertical, characterized in that the gyro platform controls signals containing signals proportional to the components of the apparent acceleration generated by accelerometers, while the control signals ly gyro platform is formed so as to provide a predetermined angle of inclination α relative to the horizontal plane gyro platform in compass meridian plane, in accordance with the expression

where α is the angle of inclination of the gyro platform (value of velocity deviation),

- the horizontal component of the absolute angular velocity of the object, ω _about - Schuler frequency, h is the coefficient of proportionality, and to ensure the removal of the value of the course of the object, the outer axis of the gimbal is installed perpendicular to the plane of the base, which is used as a platform stabilized in the horizon.

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