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RU-2861665-C1 - METHOD FOR MEASURING ANGULAR VELOCITY AND ACCELERATION PARAMETERS USING MICROMECHANICAL GYROSCOPES AND ACCELEROMETERS FOR CREATING GYROCOMPASS

RU2861665C1RU 2861665 C1RU2861665 C1RU 2861665C1RU-2861665-C1

Abstract

FIELD: measurement technology. SUBSTANCE: essence of the invention lies in the fact that in the method of measuring angular velocity and acceleration parameters using micromechanical gyroscopes and accelerometers, the axis of rotation of one movable module is positioned at an angle of 54.74° to the orthogonal axes X, Y, Z of the second fixed module attached to the object. In addition, when rotating the two sensitivity axes of the movable module, four stops are made at angles of 0°;45°;180°;225°, during which the measured values are recorded along the three axes of the fixed module and the two axes of the movable module. At the fourth stop at the end of the turn, the measured values along the three axes of the fixed module are converted into projections of the values along the two axes of the movable module, and then the obtained projections are compared with the measured values along these two axes. As a result of the comparison, the zero offset in the measurement results along the X, Y, and Z axes of the fixed module is determined, which is then subtracted from all current measurements of the fixed module. The measurement results are corrected at the end of each rotation of the movable module. EFFECT: increased measurement reliability. 1 cl, 5 dwg

Inventors

  • Nikitina Olga Nikolaevna

Dates

Publication Date
20260507
Application Date
20250409

Claims (12)

  1. A method for measuring angular velocity and acceleration parameters using micromechanical gyroscopes and accelerometers, according to which two modules are installed on board a moving object, containing triads of accelerometers and gyroscopes, the sensitivity axes of which lie along the axes of the orthogonal coordinate system X, Y, Z for the first module and the orthogonal coordinate system K, M, N for the second module, wherein the first module is fixedly fixed on the object, and the second module is rotated around the K axis with four stops, during which the projections of the measured quantities W M and W N are fixed on the axes of the moving module, the obtained measurement results are processed, excluding from them the systematic error of the zero offset of the output signal of the measuring device, the obtained values are used to correct the measurement values of the fixed module, characterized in that the rotation axis K is set at an angle of 54.74° to the axes X, Y, Z, while the rotation is carried out in the range from 0° to 225°, and back from 225° to 0° with four stops 1-0°, 2-45°, 3-180°, 4-225°, and at the first stop at an angle of 0°, the N 1 axis lies in the same plane as the Z and K axes, while at each stop, the projections of the measured quantities onto the W x , W y , W z axes are recorded and the projections of the measured quantities onto the M and N axes are calculated:
  2. W m1 = 0.707W x1 - 0.707W y1 ;
  3. W m3 = -0.707W x3 +0.707W y3 ;
  4. W n2 = -0.786W x2 +0.211W y2 +0.579W z2 ;
  5. W m2 =0.211W x2 -0.786W y2 -0.364W z2 ;
  6. W n4 =0.786W x4 -0.211W y4 -0.579W z4 ;
  7. W m4 = -0.211W x4 +0.786W y4 -0.3664W z4 ,
  8. and then at the end of the turn at the fourth stop, the zero offsets are calculated in the measurement results along the X, Y, Z axes of the fixed module:
  9. Δх=1.47 (W n2 -W n4 -W N2 +W N4 )-2.33(W m2 -W m4 -W M2 +W M4 )+1.65(W m1 -W m3 -W M1 +W M3 );
  10. Δy=1.47 (W n2 -W n4 -W N2 +W N4 )-2.33(W m2 -W m4 -W M2 +W M4 )+0.94(W m1 -W m3 -W M1 +W M3 );
  11. ΔZ=2.33 (W n2 -W n4 -W N2 +W N4 )-2.33(W m2 -W m4 -W M2 +W M4 )+1.89(W ml -W m3 -W M1 +W M3 ),
  12. after which the corresponding values of zero offsets Δх, Δy, Δz are subtracted from the measured values W X , W Y , W Z .

Description

The invention relates to measuring equipment, namely to methods for measuring angular velocity and acceleration parameters using micromechanical gyroscopes and accelerometers as applied to the navigation of moving objects and can be used for the navigation of unmanned aerial vehicles, underwater and surface vehicles, for laying oil and gas wells and various underground tunnels as a means of determining true North. A gyrocompass based on micromechanical gyroscopes and accelerometers, based on the method of this invention, is capable of determining the speed of rotation of the Earth (15°/h), thereby allowing the determination of the true direction to the North, as well as for stabilizing the position of a sea vessel, aircraft or other object in the presence of rapidly changing external conditions. A method for automatically compensating for acceleration-independent drifts in a gyroscopic device is known [1]. According to this method, the gimbal of the gyroscopic device, together with a triad of accelerometers, is rotated by a motor around the angular momentum vector. The angular position of the gimbal is recorded by an angle sensor. The gimbal rotates by a calculated angle when the parameter N, determined by mathematical processing of the signals from the gyroscope, accelerometers, and angle sensor, exceeds a predetermined threshold. This reduces the errors in the gyroscope's operation caused by the rotation of the object on which the gimbal is mounted around the gyroscope's angular momentum vector. A disadvantage of this method is the presence of an error in the gyroscope's operation, which, after the gimbal has rotated by the calculated angle, drops to zero and then increases again to a certain level at which the parameter N reaches a threshold. A known method for measuring the angular velocity and acceleration parameters from two micromechanical gyroscope units when solving an orientation problem [2]. According to this method, three modules are installed on board a moving object, where the first and second modules contain a triad of gyroscopes, the third module contains a triad of accelerometers, wherein the first two modules rotate around axes, measuring the rotation angles of the modules, and the axes themselves are positioned perpendicular to each other, the third module is fixedly attached to the object, during the movement of the object, the orientation parameters are found for each module based on their output signals, then, using the error equation and the Kalman filter, the orientation parameters of the second module are corrected, after which, based on the integrated accelerometer readings, the orientation angles of the object of course, pitch and roll are found. The use of this method reduces the requirements for the accuracy of rotation angle measurements during the rotation of the first two modules, which increases the accuracy of the object orientation. The disadvantage of this method is the object orientation errors caused by the reduced, but still present, error in determining the module rotation angle, as well as the influence of the rotating module's angular velocity on the object's orientation calculations. Furthermore, the continuous rotation of the modules requires additional operations to transmit information from the rotating module to the object. Sliding contacts, which are short-lived and unreliable, are typically used for this purpose. A method for measuring angular velocity and acceleration parameters using micromechanical gyroscopes and accelerometers is known, Russian patent No. 2766833 C1, taken as a prototype [3]. According to this method, four modules are installed on board a moving object, which contain triads of accelerometers and gyroscopes, wherein one module with orthogonal sensitivity axes X, Y, Z is positioned motionless on the object, and the three remaining modules have rotations around the axes X, Y, Z, respectively, with synchronous stops, strictly every 90°, on which the measured values are recorded, while eight projections of the values are summed onto each of the axes X, Y, Z of the moving modules, wherein four of the eight projections have different signs, which facilitates the mutual elimination of systematic errors in the zero offset from the measurement results for each of the moving axes of the three modules, the obtained projections of the values during stops are used to correct the output values of the quantities of the fixed module, ensuring its operation in continuous real time. The disadvantage of this method is its complexity, as it requires rotating three modules strictly along three orthogonal axes (X, Y, Z) with synchronous stops. This also requires strict equality of the conversion factors of all six measurement channels along the rotary axes of the moving modules. Implementing this method in the device requires a complex design, which reduces the reliability of the measurement process. The claimed invention solves the problem of reducing the comp