RU2395061C1 - Method to determine position of movable objects and integrated navigation system to this end - Google Patents

Abstract

FIELD: instrument making.

SUBSTANCE: geomagnetic and gyro systems of angular orientation are used to determine angle of motion and increase of coordinates per operating cycle. Satellite radio navigation systems are used to measure object coordinates. Initial point coordinates are allowed for to determine movable object coordinates. Current coordinates are recorded on electronic flight routing map in real time. Parametric and functional reliabilities are estimated. Results of linear analysis of measured parametres and flight deviations allow revealing most accurate readings of the system depending upon current effects. Integrated navigation system comprises linear acceleration transducer unit, magnetic field transducer unit, angular speed transducer unit, unit that couples devices by signal levels, time memory unit, high-sensitivity satellite receiver GPS/Glonass, overload transducer, calibration and digital processing unit, computation and control unit, range computation unit, exchange interface and digital graphical display.

EFFECT: higher accuracy.

12 cl, 4 dwg, 1 ex

Description

The invention relates to the field of instrumentation and can be used in navigational instruments, including with a comprehensive operating algorithm, for determining the coordinates of moving objects in the conditions of geomagnetic anomalies, natural atmospheric, imitation, barrage and electromagnetic interference, as well as in the absence or unstable reception of signals satellite radio navigation systems.

A known method of combining inertial navigation systems and integrated navigation system according to the patent [1]. The method uses an inertial navigation system with correction from the receiver of the satellite navigation system according to the correction signals generated by the correction filter according to the speed difference of the inertial navigation system and the base speed sensor, as well as to the difference of signals from horizontal accelerometers converted by the integrator and the base speed sensor. The device consists of an autonomous inertial navigation system, a satellite navigation receiver, an adder, correction filters, integrators and control filters. The specified method and device is very difficult to implement, and the device has large dimensions and power consumption, as a result of which their widespread use is limited for use in moving objects when determining location coordinates.

A known method for determining the location of moving objects and a device for its implementation according to the patent [2]. The method measures the horizontal projections of the total vector of the magnetic field of the Earth and the magnetic field of the object. In each working cycle, the average values of the projections of the total vector of tension and acceleration of gravity on the axis of the instrument coordinate system are measured. From the values of the horizontal projections of the magnetic field vector, taking into account the increment of the path and the correction of direction, determine the increment of coordinates and the angle of the direction of movement. Given the coordinates of the starting point, the coordinates of the object are determined. The device comprises magnetic field sensors, vertical sensors, a unit for calculating horizontal projections of a magnetic field, a control unit, a displacement sensor and a navigation unit. The navigation block contains a block for calculating the increment of coordinates, a block for calculating the angle, and an adder. The method and device relates to autonomous navigation systems of a magnetic type, using the Earth's magnetic field to determine the direction of movement and an odometric number system.

The disadvantages of this method and device is the low accuracy of measuring the coordinates and the angle of the direction of movement, as well as the complexity of their use. This is due to errors in determining coordinates in autonomous navigation systems of the magnetic type. Moreover, errors, depending on the size of the distance traveled, increase over time, which requires periodic correction of the determined coordinates using topographic maps, information about known coordinates, etc. The accuracy of the known method and device is reduced under conditions of external parasitic fields, from power lines, in areas of magnetic anomalies. The introduced corrections of the direction of motion depend on the magnetic declination, the approach of the meridians in a given area and the mismatch of the measuring axis of the sensor along the longitudinal axis of the moving object.

On moving systems, odometric number systems are used, based on the calculation of the number of revolutions of a wheel or a track drive. The coefficient of the path, which determines the conversion of the number of revolutions in the distance traveled, depends on the condition of the running gear: type of tires, pressure in them, etc., as well as on the nature of the terrain. All this complicates the use of the known method and device and limits the scope of their application, and geomagnetic sensors introduce large errors in determining the directional angle, because being in any locality, it is necessary to take into account the current magnetic declination specifically for a given locality.

A known method of inertial navigation and a device for its implementation according to the patent [3]. The inertial navigation method consists in using linear accelerometers operating in the mode of self-oscillations proportional to the acceleration and the period of self-oscillations. Simultaneously with the acceleration of the object is measured, the time interval during which the acceleration is measured, using the accelerometer readings, the components of the velocity vector and the radius vector are determined in the direction of the sensitivity axis of the accelerometers in this interval. The values of the accelerometer readings for each period of self-oscillations are multiplied, and the results for a particular section of the trajectory are summarized.

The disadvantages of this method and device is the low accuracy of measuring time intervals, because there is no synchronization with a single time, which significantly reduces the accuracy in the calculation of coordinates.

The closest in technical essence to the proposed is a method for determining the location of moving objects and a device for its implementation, described in the patent [4], adopted as a prototype.

The prototype method is as follows:

1) in the calibration cycle, the moving object is rotated from the starting point by 270 degrees through the fixed positions of 0.90.180 and 270 degrees and in each determine the values of the horizontal projections of the magnetic field vector;

2) correction factors are determined from control values of horizontal projections;

3) in each working cycle measure the average values of the projections of the total vector of the Earth’s magnetic field and the magnetic field of the object on the axis of the instrument coordinate system, as well as the acceleration of gravity;

4) the measured projection values, taking into account correction factors, determine the horizontal projection values of the magnetic field vectors on the axis of the horizontal coordinate system of the object;

5) the values of the horizontal projections of the magnetic field determine the angle of the direction of movement and the increment of coordinates during the working cycle;

6) determine the coordinates of the object by summing the relative coordinates and the coordinates of the starting point;

7) taking into account the coordinates of the starting point, the coordinates of the moving object are determined;

8) using satellite radionavigation systems (SRNS) measure the coordinates of the object, taking into account which carry out the correction of the relative coordinates and the coordinates of the starting point using the base speed sensor.

The prototype device, the functional diagram of which is shown in figure 1, contains a block of magnetic field sensors 2, a block of linear acceleration sensors 1, a conversion and averaging unit 13, a unit for calculating horizontal projections of the magnetic field 14, a control unit 15, a receiver of satellite radio navigation systems (SRNS ) 6, the block for calculating the angle 17, the first block for calculating the increment of coordinates 18, the first adder 19, the second block for calculating the increment of coordinates 20, the correction block 21, the block for calculating the correction factors 22, the multiplying block 23, the second adder 24, yes motion sensor 25, control panel 26, display unit 16.

The operation of the prototype device is based on the integrated processing of information received from the autonomous navigation system of the magnetic type and the SRNS receiver, which is part of the device.

The disadvantages of the known method and device is the low calibration speed in the operating mode, when moving a moving object. In addition, the magnitude of the magnetic declination is set by a constant and is taken into account only for a particular terrain, and when moving taking into account the terrain, there is no translation of the distance traveled into the projection, which leads to the rapid accumulation of the mean square error in determining coordinates over time.

The accuracy of the known method and device is also reduced under the influence of external spurious fields from power lines, in areas of magnetic anomalies, the influence of magnetic fields of neighboring objects and the magnetic field of the object itself, magnetic declination for a particular area, external directional magnetic and electromagnetic factors. Also, a disadvantage of the known method and device is the low functional and parametric reliability.

The problem to which the claimed invention is directed, is to create a method for determining the location of moving objects and an integrated navigation system using a magnetic and gyroscopic angular orientation system, with increased accuracy and reliability of measuring motion characteristics and increased functional and parametric reliability in areas with unpredictable anomalous characteristics .

The technical result that can be obtained by implementing the proposed method and system consists in increasing the accuracy of determining the coordinates and measuring the angular orientation of the moving object, increasing efficiency and simplifying calibration in the operating mode, as well as improving the reliability characteristics.

To solve the problem in a method for determining the location of moving objects, including measuring in a calibration cycle using a geomagnetic angular orientation system of control values of horizontal projections of the total vector of the Earth’s magnetic field and magnetic field, measuring the values of the projections of gravity acceleration projections averaged over the duration of the working cycle the total vector of the magnetic field of the Earth and the magnetic field of the object on the axis of the instrument coordinate system, which, taking into account the correction coefficients obtained in the calibration cycle, determines the values of the horizontal projections of the Earth's magnetic field vector on the axis of the horizontal coordinate system of the object, which determine the direction of movement, and taking into account the increment of the path, determine the increment of coordinates during the working cycle, according to which, taking into account the coordinates of the starting point, the coordinates of the object are determined; in addition, including the measurement using satellite radio navigation systems (SRNS) of the coordinates of the object, according to which, in each working cycle, the relative coordinates and coordinates of the starting point of the object are corrected, according to the invention, the axes of the gyroscopic system of angular orientation are formed in the calibration cycle in the form of a geographically oriented trihedron, one of whose axes lies in the plane of the geographic meridian, the other axis is directed east, and the third axis coincides with the direction of the gravitational field of force t tin; the control values of the projections of the angular velocity vectors onto the orthogonal axes of the instrument coordinate system are determined, the projections of the angular velocity vectors projected on the axis of the spherical coordinate system averaged over the duration of the working cycle are measured, which, using the correction coefficients obtained in the calibration cycle, determine the values of the projections of the angular velocity vectors on the axis of the instrument coordinate system, in each working cycle determine the geographical azimuth of the direction of movement of the object using gyroscopic system of angular orientation, and also determine the directional angles of the direction of movement of the object during joint processing using geomagnetic, gyroscopic and satellite systems, from the obtained values of the apparent acceleration of movement during the working cycle, determine the increment of the path, previously obtained values of horizontal projections of the magnetic vectors of the magnetic vectors fields and the values of the projections of the angular velocity vectors determine the coordinates of the moving object, which are visually fixed on the electric onnoy map in each operating cycle in real time; at the same time, they analyze the coordinates and directional angles of the direction of movement obtained earlier, according to the results of secondary processing in the autonomous segment of the navigation algorithm, taking into account the linear analysis of the deviations, take into account the readings of the system that gives the most accurate readings depending on the current external influences; at the same time, the processes and functions performed by the above-described navigation algorithm are synchronized with a single time scale.

Moreover, in the method, the values of the projections of the angular velocity vectors on the axis of the instrument coordinate system are determined from the system of differential equations of motion of the angular velocity sensor, while the conversion of the angular velocity vectors from the spherical coordinate system to the instrument coordinate system is performed using the transition matrix; in each working cycle, differential corrections from the SRNS are received; synchronization with a single time scale is carried out by transmitting a pulse signal once a second, the leading edge of which with high accuracy corresponds to the beginning of a second of a single time; when determining the directional angles of the direction of movement of the object, the effective magnetic declination is taken into account specifically for a given area; the magnitude of the increment of the path is determined by the obtained values of the apparent acceleration of movement during the working cycle and / or using the odometric number system of the path according to a deterministic algorithm for calculating the distance traveled.

The solution to this problem is also achieved by the fact that in the navigation system for determining the location of moving objects, containing a block of linear acceleration sensors, a block of magnetic field sensors and a receiver of satellite radio navigation systems (SRNS), according to the invention, a block of angular velocity sensors, a block matching devices by signal levels , time storage unit, overload sensor, calibration and digital processing unit, calculation and control unit, path reckoning unit, digital graphic display and inte face exchange, and the outputs of the linear acceleration sensor block, the magnetic field sensor block, and the angular velocity sensor block are connected, respectively, to the first, second, and third inputs of the device matching unit according to signal levels, the first, second, and third outputs of which are connected to the corresponding inputs of the calibration block and digital processing, the first, second and third outputs of which are connected to the corresponding inputs of the calculation and control unit, the fourth output of which is connected to the input of the exchange interface, the output of which connected to the sixth input of the calculation and control unit; in addition, the output of the linear acceleration sensor unit is connected to the first input of the dead reckoning unit, and through the overload sensor, to the fourth input of the calculation and control unit, the first output of which is connected to the input of the angular velocity sensor unit, and the second output of the calculation and control unit is connected to the input SRNS receiver, the first output of which is connected through the time storage unit to the eighth input of the calculation and control unit, and the second output is connected to the seventh input of the calculation and control unit, the third output of which is connected to Odom digital graphic display, and the fifth calculation unit and output control connected to the second input of dead reckoning, an output connected to a fifth input of the computing and control.

Moreover, in the navigation system, the calculation and control unit is configured to determine the coordinates of the location, directional angles of the direction of movement, magnetic and geographical azimuth, range and angles to the control points of the route, the distance traveled and the speed of moving ground objects based on the integrated processing of information received from the blocks linear acceleration sensors, magnetic field sensors and angular velocity sensors, as well as from the SRNS receiver. The time storage unit is capable of issuing single-time clock signals, signals for synchronizing system units with a single time, providing constant reference to a single time scale, and storing time with high accuracy. The calibration and digital processing unit is configured to scale analog signals at a given level and approximate the voltage into a binary code. The overload sensor is capable of generating a digital alarm (blocking) signal to eliminate the second type of ballistic error (acceleration-attenuation error) of the angular velocity unit for the duration of the error elimination, and when operability is restored, to generate a digital operation permission signal.

The invention is illustrated using the following drawings:

figure 2 presents the coordinate diagram of a moving object;

figure 3 shows a vector diagram of the movement of the route of a moving object using geomagnetic and gyroscopic systems of angular orientation, corrected by a satellite navigation system;

figure 4 presents a block diagram of an integrated navigation system for determining the location of a moving object.

The proposed method for determining the location of moving objects is as follows.

At the beginning, using the SRNS, the initial coordinates of the object are determined, or manually entered using topographic maps.

Then, in the calibration cycle using the geomagnetic navigation system of angular orientation, control values of horizontal projections of the total vector of the Earth’s magnetic field strength and the object’s magnetic field are determined.

- лежит в плоскости географического меридиана, другая ось

- направлена на восток, а третья ось

- совпадает с направлением гравитационного поля силы тяжести.In the calibration cycle, the axes of the gyroscopic system of angular orientation are formed in the form of a geographically oriented trihedron, in which one axis

- lies in the plane of the geographical meridian, the other axis

- directed east, and the third axis

- coincides with the direction of the gravitational field of gravity.

In each working cycle, using the geomagnetic and gyroscopic systems of angular orientation, the projection values of the projections of the total vector of the Earth's magnetic field and the magnetic field of the object, the projections of the angular velocity vectors and the values of the projections of the acceleration of gravity on the axis of the instrumental coordinate system are measured.

Using the measured values of the above projections, taking into account the correction coefficients obtained in the calibration cycle, the horizontal projections of the magnetic field vectors on the axis of the horizontal coordinate system of the object and the projections of the angular velocity vectors on the axis of the spherical coordinate system are determined.

The values of the apparent acceleration of movement during the working cycle are measured, by which, by means of an integral transformation in time, the speed of the object is calculated, by which, by means of an integral transformation in time, the path traveled by the object and the projection of the path are calculated taking into account the tilt angles of the object, directional angles and corrections driving directions.

In addition, the path increment value is determined using the odometric number system of the path using a deterministic algorithm for calculating the distance traveled.

The geographical azimuth of the direction of motion of the object is measured using a gyroscopic system of angular orientation, and the process of complex measurement of the azimuthal angle of the direction of motion using geomagnetic and gyroscopic systems of angular orientation is also carried out.

The directional angles and coordinates of the object are determined, according to which, in each working cycle, the relative coordinates and coordinates of the object's starting point are corrected, and the process of complex measurement of the azimuthal angle is carried out using the SIRS, geomagnetic and gyroscopic systems of angular orientation.

The values of the horizontal projections of the magnetic field vectors and the projections of the angular velocity vectors determine the angles of the direction of motion, taking into account the increment of coordinates during the working cycle, directional angles of the direction of motion, magnetic and geographical azimuth, distance traveled and speed of moving ground objects based on integrated information processing, coming from geomagnetic and gyroscopic navigation systems, as well as from the receiver SRNS.

Given the coordinates of the starting point, determine the coordinates of the moving object obtained from navigation systems with geomagnetic and gyroscopic angular orientation.

Next, the relative coordinates of the moving object are determined by summing the increment of the coordinates of the moving object, previously measured in each working cycle.

Then determine the coordinates of the moving object by summing the relative coordinates and the coordinates of the starting point.

The current values of the coordinates of the object, which are visually recorded on the electronic map of the route in real time, evaluate the parametric reliability of the system. At the same time, the coordinates are calculated based on the values obtained from geomagnetic, gyroscopic and satellite systems, as well as directional angles of direction of movement.

According to the results of a complex secondary processing algorithm in an autonomous segment, which can be classified as a single-point deterministic prediction algorithm, taking into account a linear analysis of the deviations, the readings of the system that produces the most accurate readings depending on the current external influences are taken into account.

At the same time, the processes and functions performed by the above-described navigation algorithm are synchronized with a single time scale.

When the coordinate values diverge in the autonomous mode, the reliability of the measurements is evaluated, the zones of magnetic, electromagnetic, ionization, and gravitational anomalies are determined. The functional reliability of the system is evaluated.

Using SRNS, the coordinates of a moving object are measured, taking into account which the initial point, relative coordinates and the angular orientation of the object are corrected.

If necessary, exchange information with a workstation.

The present invention can be implemented using a device representing an integrated navigation system, a block diagram of which is presented in figure 4.

The proposed integrated navigation system for determining the location of moving objects contains a block of linear acceleration sensors 1, a block of magnetic field sensors 2, a block of angular velocity sensors 3, a unit for matching devices according to signal levels 4, a time storage unit 5, a receiver of satellite radio navigation systems (SRNS) 6, which can be used as a highly sensitive GPS / Glonass satellite receiver, overload sensor 7, calibration and digital processing unit 8, calculation and control unit 9, counting unit track 10, exchange interface 11, and digital graphic display 12. The outputs of the linear acceleration sensor block 1, the magnetic field sensor block 2, and the angular velocity sensor block 3 are connected, respectively, to the first, second, and third inputs of the device matching unit according to signal levels 4, the first, second and third outputs of which are connected respectively with the first, second and third inputs of the calibration and digital processing unit 8, the first, second and third outputs of which are connected with the first, second and third inputs of the unit calculation and control eye 9, the fourth output of which is connected to the input of the exchange interface 11, the output of which is connected to the sixth input of the calculation and control unit 9; in addition, the output of the linear acceleration sensor unit 1 is connected to the first input of the dead reckoning unit 10, and through the overload sensor 7 to the fourth input of the calculation and control unit 9, the first output of which is connected to the input of the angular velocity sensor (DLS) 3, and the second the output is connected to the input of the SRNS receiver 6, the first output of which through the time storage unit 5 is connected to the eighth input of the calculation and control unit 9, and the second output of the SRNS 6 receiver is connected to the seventh input of the calculation and control unit 9, the third output of which is connected to swing digital graphic display 12, and the fifth calculation unit and output control means 9 is connected to the second input unit numeral path 10, whose output is connected to a fifth input of the computing and control means 9.

The operation of the device is based on the integrated processing of information received from the block of linear acceleration sensors 1, the block of magnetic field sensors 2, the block of angular velocity sensors 3 and the SRNS receiver 6.

In the initial state, the blocks of angular velocity sensors 3 (gyroscopic system of angular orientation) and linear acceleration sensors 1 go into the initial exhibition mode, and according to the correction tables, the axes of the block of angular velocity sensors 3 are accurately calibrated.

It is known that the North Magnetic Pole does not really coincide with the true geographical North. The true geographical North is the axis of rotation of the Earth. At various points on the planet, this difference, called the declination of λ, can reach ± 25 °. The declaration depends on the geographical location and are determined from the geodetic tables. It can be seen from the foregoing that in order to accurately determine the direction of movement to the North (azimuth) when using a geomagnetic angular orientation system operating in an autonomous mode, iteration is necessary to perform two iterations:

1) measurement of the horizontal components of the Earth’s magnetic field on the axis of the instrument coordinate system H _XM , H _YM (the roll of the object must be taken into account);

2) adding or subtracting the declaration of λ to correct the course to the true geographical North.

If there is no reception of the SRNS signals in the calculation and control unit 9, the coordinates of the object's starting point (the initial coordinates of the object) X ₀ , Y ₀ and the magnetic declination (directional correction Δα for a given area) are entered, which are corrected in the calculation and control unit 9 using the correction spreadsheet embedded in the navigation algorithm of the calculation and control unit 9.

In the measurement mode, the linear acceleration sensor block 1, the magnetic field sensor block 2 and the angular velocity sensor block 3 continuously generate analog signals at their outputs proportional to the corresponding values of the projections of the vectors H _{XM of the} total magnetic field of the Earth and the magnetic field of the object, the projections of the gravity acceleration vectors A _X , A _Y , A _Z and the projections of the angular velocity vectors V _X , V _Y , V _Z on the axis of the instrument coordinate system OXYZ (figure 2). Analog signals from the sensor blocks 1, 2, 3 are respectively supplied to the first, second and third inputs of the device matching unit according to signal levels 4, where noise reduction and level normalization occur. Then, from the outputs of block 4, the analog signals arrive respectively at the first, second, and third inputs of block 8, where they undergo separate digital processing with subsequent discretization using an analog-to-digital converter, which is a serial approximation converter that can be calculated by the formula:

where T _s is the sampling period;

T _b , - time scan;

N _S is the multiplier.

,

,

оцифрованные значения проекций векторов напряженности магнитного поля

,

, и оцифрованные значения проекций векторов угловой скорости

,

,

c соответствующих выходов блока 8 поступают соответственно на первый, второй и третий входы блока 9, где проводится цифровой расчет горизонтальных проекций векторов магнитного поля Земли H_XM, H_YM, поступающих с блока 2, расчет проекций векторов ускорения силы тяжести A_XM, A_YM, A_ZM, поступающих с блока 1, и проекций векторов угловой скорости

,

Then, the corrected and digitized values of the projections of the gravity acceleration vectors

,

,

digitized projections of the magnetic field vectors

,

, and digitized projections of angular velocity vectors

,

,

c the corresponding outputs of block 8 are received respectively at the first, second and third inputs of block 9, where digital calculation of horizontal projections of the Earth’s magnetic field vectors H _XM , H _YM from block 2 is carried out, calculation of the projections of the gravity acceleration vectors A _XM , A _YM , A _ZM coming from block 1 and projections of angular velocity vectors

,

coming from block 3. In addition, from the first output of block 1, analog signals are fed to the input of block 7 and the first input of block 10, from the outputs of which the signals respectively arrive at the fourth and fifth inputs of block 9. During mechanical overloads that occur during the movement of a moving object , the overload signal from block 1 is fed to the input of the overload sensor 7, from the output of which the signal is fed to the fourth input of block 9, from the first output of which a blocking signal is fed to the input of the block of angular velocity sensors 3, as a result of which its slave that is locked for the duration of an overload. In this case, the processing of information about the movement of a moving object is carried out using a geomagnetic angular orientation system using blocks 1 and 2. At the end of the overloads from the output of the overload sensor 7, the enable signal arrives at the fourth input of unit 9, from the first output of which the operation enable signal for block 3 is received at his entrance. Simultaneously with the acceleration of the object, the time interval of the movement of the object is measured in block 10, which measures the apparent acceleration of motion, which includes the acceleration of gravity; by integrating the obtained value of the acceleration of movement, the speed is calculated, followed by integration of the speed to determine the distance traveled. The coordinates correction signals of the moving object from the first output of the SRNS 6 receiver are fed to the input of the time storage unit 5, from the output of which the signal is fed to the eighth input of the unit 9, to synchronize the time stamp and ensure temporary stability. From the second output of block 9, the request signal is input to the receiver of the SRNS 6, from the second output of which the response signal is supplied to the seventh input of block 9. To control the accuracy of coordinate calculations and information exchange, an exchange interface block 11 is introduced, the signal from the output of which goes to the sixth input of the block 9, from the fourth output of which the response signal is fed to the input of the exchange interface 11. The signal from the third output of block 9 is fed to the input of a digital graphic display 12, which allows the use of electronic cards for visual observation niya and control the operation of the navigation system.

,

,

,

,

,

,

,

,

и по значению вычисленного приращения пройденного пути δS, с учетом поправки направления Δα, определяют приращение координат в блоке 9. В блоке 9 определяются приращения пройденного пути δS за каждый рабочий цикл в соответствии с фиг.3. По значениям приращений координат, измеренных в каждом рабочем цикле, определяют относительные координаты ΔX, ΔY в соответствии со значениями исходной точки X₀, Y₀. При отсутствии приема сигналов СРНС значения относительных координат и координат исходной точки геометрически суммируются в блоке 9, который обеспечивает определение координат с отображением навигационной информации на цифровом графическом дисплее 12.By values

,

,

,

,

,

,

,

,

and from the value of the calculated increment of the traveled path δS, taking into account the correction of the direction Δα, determine the increment of coordinates in block 9. In block 9, the increments of the traveled path δS for each working cycle in accordance with Fig.3 are determined. From the values of the increments of the coordinates measured in each working cycle, determine the relative coordinates ΔX, ΔY in accordance with the values of the starting point X ₀ , Y ₀ . In the absence of reception of SRNS signals, the values of the relative coordinates and the coordinates of the starting point are geometrically summed in block 9, which provides the determination of coordinates with the display of navigation information on a digital graphic display 12.

значению поправки направления Δα и значению деклинации λ, проводит расчет дирекционного угла α направления движения.With a sharp start or sudden braking of the object, the linear acceleration sensor block 1 goes into limiting mode and the overload sensor 7 is activated, the signal of which arrives at the fourth input of block 9, where a response signal is generated, which is fed to the input from the first output of block 9 through the feedback circuit block 3, the operation of which is blocked for the duration of the overload of block 1, after which a signal is issued allowing the operation from the first output of block 9 to the input of block 3. During the action of the blocking signals, I calibration of the angular velocity sensor unit 3 in order to eliminate errors due to an error of the acceleration-damping (ballistic error of the second kind). At the time of blocking the angular velocity sensors in block 9, the increments of coordinates are calculated according to the values of H _XM , H _{YM of the} block of magnetic field sensors 2. In each working cycle, block 9 is calculated by the values of the horizontal projections H _XM , H _YM , the values of the projections of the angular velocities

the value of the direction correction Δα and the value of the declination λ, calculates the directional angle α of the direction of motion.

The calculation and control unit 9, operating in accordance with the above-described navigation algorithm, can be implemented on the FPGA and the processor of the AWP family.

Digital graphic display 12 is designed for visual display of measured parameters on electronic maps in real time, coming from the SRNS and navigation systems with gyroscopic and magnetic angular orientation, working in stand-alone mode.

The introduction in the present invention of the operation of calculating the angular velocity of an object when using the angular velocity sensor unit 3 for orientation to the true geographic meridian, the introduction of an overload sensor 7, including the operation of calculating the angle using magnetic sensors (secondary processing in the autonomous segment), to compensate for errors in the TLS ( gyrocompass), arising from the accelerated movement of the object, with sharp acceleration and sharp braking of the object associated with a ballistic error of the second kind, or the acceleration-damping, the reorientation of the gyrocompass to the geographical meridian in the case of work in the north, as well as the calculation of the difference in the directional angle between the magnetic and geographical north, so that depending on the orientation of the gyrocompass (north-south), to compensate for the angular difference (declination λ≈ ± 11.5 °). The introduction of the exchange interface 11 allows you to organize communication with the workstation, and with the help of the time storage unit 5 provide stabilized second marks (temporary stability), integrating the apparent acceleration in time, calculate the speed of the object and then integrate the speed to determine the path traveled by the object through block 10. The dead reckoning unit can be implemented on MK series controllers with the ability to connect additional odometric sensors and accelerometers.

All of the above allows you to provide increased accuracy and reliability of determining the coordinates of the object in comparison with the prototype.

This is achieved by:

1. The determination of relative coordinates is carried out on the basis of integrated processing of information, taking into account its reliability, coming from navigation systems with geomagnetic and gyroscopic angular orientations, operating in standalone mode, and SRNS. At the same time, on the one hand, the systematic errors of the autonomous navigation system are taken into account, and on the other hand, the geomagnetic autonomous system allows you to compensate for the gyrocompass errors, because the magnetic field sensors do not respond to the inertial components of the movement of a moving object.

2. The continuous operation of the device is ensured, which does not require the need for a separate calibration cycle, this is achieved by introducing an overload sensor 7, which responds to the excess signal received from block 1, and generates a logical signal that goes to block 9, and then from it the output signal enters block 3 and turns it off for the period of extinguishing of the exciting inertia forces during which the block 3 is calibrated. At the end of the block 3 calibration, a control signal is generated in block 9 for switching operating mode from block 2 to block 3.

The sensor blocks 1 and 3 can be implemented, for example, on microcircuits of the ADIS16355 type, which are precisely aligned along the axes and calibrated by the offset and sensitivity of the device.

The block of magnetic field sensors 2 can be implemented, for example, on a chip type MMC212 × MG company MEMSIC.

As an overload sensor, a comparator with feedback and a pic microcontroller can be used.

3. The introduced time storage unit 5 synchronizes the second timestamp received from the SRNS 6 receiver, and in standalone mode provides temporary system stability, which increases the accuracy of calculating the path and determining coordinates. As a time storage unit, for example, a precision quartz oscillator with double thermostating can be used.

4. The introduction of the exchange interface 11 provides information exchange with a workstation.

5. The introduction of a digital graphic display 12 allows the use of electronic maps, to monitor in the form of graphs, and also allows visual control of the operation of the navigation system.

Compared with the prototype, which requires a forced calibration cycle, and therefore it was necessary to stop the operation of the device, in the present invention provides continuous operation of the system due to the interchangeability of autonomous navigation systems. Correction of the relative coordinates and the coordinates of the starting point is made both from the satellite navigation system and from autonomous navigation systems. In addition to increasing accuracy, it is worth noting the higher parametric and functional reliability and stability of the proposed system, especially under the influence of interference, in areas of magnetic anomalies, in areas of unstable reception of SRNS signals, etc. The use of a highly sensitive GPS / Glonass 6 satellite receiver as SRNS provides an initial snap of the starting point without operator intervention.

All of the above allows you to provide a solution to the problems to which the claimed invention is directed.

Consider a vector diagram of the moving route of a moving object, using gyroscopic and magnetic navigation systems, corrected by the satellite navigation system, presented in figure 3, where it is indicated:

- RO - coordinates of the starting point;

- RD - increment of autonomous coordinates for one measurement cycle;

- RT - coordinate offset relative to the starting point;

- RC - the current coordinates of the object (the result of calculations during joint processing);

- RG - coordinates received from the satellite navigation system;

- RS - coordinates not involved in the calculation of the coordinates of the object;

- SS - maximum permissible error coefficient (if it exceeds, then filtering is introduced).

At the starting point Ro, the calibration and initial exhibition of navigation systems are performed using corrective corrections from the SRNS. In the first cycle of increments of the autonomous measurement coordinates, the coordinates obtained from three navigation systems are fixed. This paragraph visually demonstrates the accuracy of the integrated system. In the second cycle, as a result of the influence of extreme inertia forces arising in the process of moving a moving object (slipping, sudden braking, acceleration, etc.), the gyroscopic system gives errors (which can fit into the allowable limits of calculation errors). In this case, the most accurate results are obtained from the magnetic navigation system. The third cycle demonstrates the adequate operation of an integrated system with good accuracy characteristics. In the fourth cycle, the system fixes the zone of anomalies (geomagnetic, electromagnetic, etc.), where the magnetic system gives an error that is outside the tolerance, and the coordinates in the autonomous mode are estimated by the gyroscopic navigation system. Thus, the parametric reliability of the proposed navigation system is provided. In the event of a failure or failure of one of the systems, functional reliability is provided by another navigation system.

Consider an example of the implementation of the proposed method.

Previously, before the start of the navigation measurement mode, a calibration cycle is carried out in which the horizontal projections of the magnetic field H _XM , H _YM are measured in four ellipse orientations corresponding to the directions 0, 90, 180, and 270 degrees.

At the starting point, using blocks 1, 2, 3, the values of the projections A _X , A _Y , A _{Z of the} acceleration of gravity, the projections H _XM , H _{YM of the} total intensity vector of the MPZ and the stray magnetic field of the moving object and the projections V _X , V _{Y are measured} , V _Z angular velocities on the orthogonal axis of the instrument coordinate system of the moving object. The axis of the instrument coordinate system (see figure 2) are adjusted as follows. The OY axis is directed along the axis of the moving object in the direction of its movement, the OX axis is along the transverse axis of the moving object (PO), and the OZ axis is along its vertical axis.

,

,

и

,

,

и

,

,

. Проекции

,

,

, вектора магнитного поля Н, проекции

,

,

вектора кажущегося ускорения А и проекции

,

,

угловой скорости V на оси приборной системы координат вычисляются из показаний блоков датчиков 1, 2 и 3 следующим образом:Denote the readings of the sensors of the blocks 1, 2, 3, respectively

,

,

and

,

,

and

,

,

. Projections

,

,

, magnetic field vector H, projection

,

,

vectors of apparent acceleration A and projection

,

,

angular velocity V on the axis of the instrument coordinate system is calculated from the readings of the sensor blocks 1, 2 and 3 as follows:

The zero offsets ΔH _K , ΔA _K ΔV _K of the sensor blocks 1, 2, 3 included in these formulas, as well as their scale factors P _HK , P _AK , P _VK are in the process of initial calibration of the sensor block. In addition, the parameters ΔH _K , P _HK , P _VK can be refined and changed in the process of eliminating deviation.

The sensor blocks 1, 2, 3 are fixed on the movable object so that the OZ axis is directed orthogonal to the plane of the base of the object, and the OY axis is parallel to the vertical plane passing through the longitudinal axis of the object.

It is known that the gyroscopic system of angular orientation does not evaluate external influencing factors, being an inertial system that does not require conversion of the measured values, while to determine the magnetic course of a moving object from the instrument coordinate system, it is necessary to synthesize an auxiliary coordinate system in order to reliably estimate the Earth's magnetic field which acts at a given point on a moving ground object OX _M Y _M Z _M (Fig. 2), the axis OZ _{M of} which is directed vertically and the axis OY _M is horizontally in direction of movement. The projections H _XM , H _YM , H _ZM of the magnetic field on the axis of this coordinate system are calculated using the matrix C of the transition from the coordinate system OXYZ to OX _M Y _M Z _M :

The elements of the rows of the matrix C coincide with the components of the unit vectors i _M , j _M , k _M in the coordinate system OXYZ.

The apparent acceleration vector A, measured by accelerometers, consists of the true acceleration vector relative to the earth's surface and the vector g (minus g), where g is the acceleration of gravity. The unit vector directed along the axis OZ _M can be defined by the expression:

- величина вектора А.Where

is the magnitude of the vector A.

The components of the vector i _M in the instrument coordinate system are found from the condition of perpendicularity to the vertical plane passing through the instrument axis OY:

For the vector j _M we get:

Thus, the matrix C has the form:

We determine the horizontal components of the magnetic field vector.

The magnetic azimuth of the direction of motion (magnetic course) of the object α _m is determined by these components as follows:

The geographic azimuth of the direction of motion (true course) of an object is determined as follows.

Using the mathematical apparatus of spherical trigonometry, we can write the first group of algorithms for azimuthal orientation of objects in the form:

where α is the azimuthal angle between the instrument axis Y and the plane of the geographic meridian;

µ is the angle between the Y axis and the line of intersection of the equatorial plane with the horizon plane;

ω is the angular velocity of the Earth;

φ ₀ - latitude of location;

t is the time of movement of the CRS, measured from the moment of the initial exhibition;

Δω, Δλ - increment of coordinates in latitude and longitude. The presented algorithms correspond to the case when one of the axes of the gyroscope is initially aligned vertically. In this case, the first algorithm is used for azimuthal determination of the axes of a stationary object, and the second for a moving object. For an arbitrary Δφ ₀ and initial Δλ ₀ exhibition of axes, the parameters of the TLS free motion will differ from the cases considered by the angular parameters. The determination of the angular parameters for an arbitrary Δφ ₀ and initial Δλ ₀ exhibition of axes is carried out immediately before the azimuthal orientation of objects according to the algorithm:

Then the angular position ψ of the lines of the TLS axes (with the base stationary) relative to the plane of the meridian can be calculated by the algorithm:

With the azimuthal orientation of moving objects, the algorithm for calculating the angle ψ has the form:

The second group of algorithms for azimuthal orientation of objects, taking into account the drift of a real gyroscope, can be obtained from the system of differential equations of motion of the TLS:

where V _X , V _y , V _Z - the angular velocity of rotation of the gyroscope relative to the axes of the geographical coordinate system;

M _x , M _y - known disturbing moments;

H is the kinetic moment of speed necessary to obtain the Coriolis force during rotation.

The resulting system after linearization should be solved in the deviations of the axes of a real gyroscope from the axes of an ideal (unperturbed) gyroscope:

where ψ _H , θ _H are the calculated angular positions of the angular axes and the vertical axis of rotation of the TLS relative to the geographical coordinate system;

Δφ, Δθ are the deviations of the axes of a real gyroscope relative to the axes of an ideal gyroscope, which are specified (corrected) during periodic checks simultaneously with the determination of variable coefficients of the equations.

A linear system of differential equations in deviations for a real gyroscope based on system (5) can be written in the form:

where the coefficients:

Linear acceleration sensors are oriented along the axes of the instrument coordinate system OXYZ. The transformation of vectors from a spherical coordinate system to the instrument is carried out using the transition matrix:

The system of linearized equations (19) is solved by iterative methods based on difference schemes in real time.

The totality of all particular solutions or a combination of individual ones allows you to get a set of algorithms for solving azimuthal orientation problems for a wide variety of situations.

To determine the directional angle α, it is necessary to take into account the value of the directional correction Δα, which is equal to the sum of the magnetic declination θ, the hardware correction Δα _A , caused by the deviation of the axis OY of block 2 from the longitudinal axis and the declination ± λ.

The current coordinates of the object during joint (complex) processing are in accordance with Fig 3:

Summing up the increment of coordinates during one measurement cycle, the values of the current coordinates of the object are obtained:

The root-mean-square error S _{A of the} coordinates calculated in the autonomous mode linearly increases at each step of the calculations

where δS is the expected error of the increment of coordinates at one step of the calculations.

In the absence of SRNS signals, the coordinates in each autonomous cycle are calculated in accordance with the expression:

,

начальной точки уточняются в соответствии с формулами:In this case, the estimated value of the mean square error increases in accordance with (24). Upon receipt of the coordinates X _R and Y _R from the SRNS, the previously calculated relative coordinates ΔX _T , ΔY _T and coordinates

,

starting points are specified in accordance with the formulas:

The elements K ₁ and K _{2 of} the gain matrix are calculated as follows:

where P _ij are the elements of the correlation matrix of the extrapolation errors P. This matrix is updated in each cycle of processing the observation results (upon receipt of the coordinates X _R , Y _R from the SRNS) in accordance with the formula:

, после чего величина S_A обнуляется. Для вычислений по формуле (28) необходимо задать матрицу Р в начальный момент времени. Начальное значение P=P₀ определяется величиной дисперсии D₀ координат начальной точки в момент старта:The dispersion D _{A of the} increments of the autonomous coordinates in the period between the last two packages of the SRNS is defined as

after which the value of S _A is reset. For calculations by formula (28), it is necessary to specify the matrix P at the initial instant of time. The initial value P = P ₀ is determined by the dispersion value D _{0 of the} coordinates of the starting point at the time of start:

This dispersion depends on the conditions of the beginning of motion.

The described algorithm ensures reliable operation of the system both in the presence and in the absence of SRNS packages. If there are no signals from the SRNS, the coordinates are calculated in the autonomous segment with the corresponding gradual accumulation of errors. Upon receipt of radionavigation information, even after a long period of operation in the autonomous mode, as follows from (13) - (15), the coordinates are rather quickly refined and their root-mean-square error decreases. With further joint work, the autonomous equipment actually performs smoothing in the dynamic mode of coordinates from the SRNS, thereby making them more accurate. Separate deliberately false rough jumps of the SRNS coordinates in this mode can simply be discarded. Own error of autonomous systems in this case (during several cycles) is very insignificant.

As already noted, the errors in determining the coordinates during long-term operation of the equipment in stand-alone mode largely depend on the choice of the correct values of the path factor K _S and the direction correction Δα. Additional information from the SRNS receiver allows continuous correction of these parameters during movement. For this, two arrays of the same fixed length are formed, in which the results of selective 10-20 last coordinate measurements by the SRNS receiver and autonomous equipment are stored. The sample is required so that the length of the plot on which the coordinates are compared significantly exceeds the error of the SRNS measurements. The recording of the next points in these arrays is carried out simultaneously, provided that there is no sharp jump in the coordinates from the receiver of the SRNS, and the distance to the previous point (according to autonomous calculations) is at least 10 meters. Before recording the next point, a comparison of the increments of the coordinates from the start to the end point of both arrays is performed. Let L _R and L _A be the distance in meters between the first and last points, respectively, for the SRNS and autonomous arrays. If the difference of these distances in absolute value does not exceed the expected permissible error and L _A > (100 ÷ 200) m, the parameters K _S and Δα are smoothly corrected using the formulas:

where δα is the angle in degrees between the directions from the first to the last point, respectively, for SRNS and autonomous arrays,

Q _S and Q _α are the filtration parameters determined experimentally.

The procedure for calculating the speed according to the longitudinal acceleration data is performed in the calculator and control unit 9 of a special program. As a numerical integration method, the Simpson method is used, the general formula of which is:

a and b are the lower and upper limits, respectively;

n is an even number of equally spaced samples in time.

Calibration in the operating mode is carried out in case of detection of errors associated with a second-order ballistic error, or an acceleration-damping error. In this case, the gyrocompass is blocked by an overload signal, which depends on the value of the moment of inertia forces. Inertial deviation manifests itself in the form of damped oscillations after the end of the maneuver of a moving object (course and / or speed).

The inertial error of the first kind is of greatest importance at the time of the end of the maneuver; the inertial error of the second kind reaches its greatest value after the end of the maneuver. The combination of the above errors forms the total error of the gyrocompass, subdivided into a systematic and random component. Calibration is also carried out in case of other errors associated with external abnormal environmental factors. Interchangeability of sensors is envisaged during operation, for example, a block of angular velocity sensors on a block of sensors of the Earth's magnetic field and / or vice versa. So in the event of a failure of some sensors, the system measures by other sensors, a constant operating mode of the system is ensured, thereby increasing its efficiency, as well as functional reliability.

From the foregoing, it follows that the use in the proposed method of integrated information processing using geomagnetic and gyroscopic navigation systems allows to detect and eliminate errors of the SRNS receiver, and also acts as a filter that sharply reduces random non-correlated errors of individual measurements. In addition, such navigation systems can operate independently if it is impossible to receive SRNS signals.

In turn, the information from the SRNS receiver allows you to filter out measurement errors of geomagnetic and gyroscopic navigation systems, including those caused by short-term exposure to spurious external magnetic fields, and makes it possible to automatically adjust the tuned parameters of the integrated navigation system - direction correction DAp, path coefficient Ks and declination ± λ. In the joint processing of information, the shortcomings of both systems are mutually compensated, and the complex is more stable with respect to external influences.

Thus, in the proposed method, the introduction of integrated processing of information from moving objects using geomagnetic and gyroscopic systems of angular orientation, as well as the receiver SRNS can improve the reliability of assessing the location of the object and evaluate the parametric reliability of the system.

Information sources

1. RF patent No. 2082098 "A method for integrating inertial navigation systems and a complete navigation system", 2007

2. RF patent No. 2098764 "Method for determining the location of moving objects and a device for its implementation", 1997

3. RF patent No. 2334198 "Inertial navigation method and device for its implementation", 2008

4. RF patent No. 2202102 "Method for determining the location of moving objects and a device for its implementation", 2003

Claims (12)

1. A method for determining the location of moving objects, including measuring in a calibration cycle using a geomagnetic angular orientation system of control values of horizontal projections of the total vector of the Earth’s magnetic field and magnetic field, measuring the values of the projections of gravity acceleration projections averaged over the duration of the work cycle Earth’s magnetic field and the object’s magnetic field on the axis of the instrument coordinate system, according to which, taking into account the coefficients of the reaction obtained in the calibration cycle, determine the values of the horizontal projections of the vector of the magnetic field of the Earth on the axis of the horizontal coordinate system of the object, which determine the angle of the direction of movement, and taking into account the increment of the path, determine the increment of coordinates during the working cycle, according to which the coordinates of the starting point determine the coordinates of the object; in addition, it includes measuring with the aid of a receiver of satellite radio navigation systems (SRNS) the coordinates of the object, according to which, in each working cycle, the relative coordinates and coordinates of the starting point of the object are corrected, characterized in that the axis of the gyroscopic system of angular orientation are formed in the calibration cycle in the form of a geographically oriented a trihedron, one of the axes of which lies in the plane of the geographic meridian, the other axis is directed east, and the third coincides with the direction of the gravitational gravity; the control values of the projections of the angular velocity vectors onto the orthogonal axes of the instrument coordinate system are determined, the projections of the angular velocity vectors projected on the axis of the spherical coordinate system averaged over the duration of the working cycle are measured, which, using the correction coefficients obtained in the calibration cycle, determine the values of the projections of the angular velocity vectors on the axis of the instrument coordinate system, in each working cycle determine the geographical azimuth of the direction of movement of the object using gyroscopic system of angular orientation, and also determine the directional angles of the direction of movement of the object during joint processing using geomagnetic, gyroscopic and SRNS; determine the increment of the path along which the projection of the path is recalculated taking into account the angle of inclination of the object, the directional angles and the correction of the direction of motion, the previously obtained values of the horizontal projections of the intensity of the magnetic field vectors and the values of the projections of the angular velocity vectors determine the coordinates of the moving object, which are visually fixed on an electronic map in each working cycle in real time; at the same time, they analyze the coordinates and directional angles of the direction of movement obtained earlier, according to the results of the secondary processing in the autonomous segment of the navigation algorithm, taking into account the linear analysis of the deviations, take into account the readings of the system that gives the most accurate readings depending on the current external influences; while the processes and functions performed by the above-described navigation algorithm are synchronized with a single time scale. 2. The method according to claim 1, characterized in that the projection values of the angular velocity vectors on the axis of the instrument coordinate system are determined from the system of differential equations of motion of the angular velocity sensor, and the vectors are converted from the spherical coordinate system to the instrument coordinate system using a transition matrix. 3. The method according to claim 1, characterized in that in each duty cycle receive differential corrections from the receiver SRNS. 4. The method according to claim 1, characterized in that they exchange information with a workstation. 5. The method according to claim 1, characterized in that the synchronization with the scale of a single time is carried out by transmitting a pulse signal once a second, the leading edge of which with high accuracy corresponds to the beginning of a second of a single time. 6. The method according to claim 1, characterized in that when determining the directional angle of the direction of movement of the object, the effective magnetic declination is taken into account specifically for a given area. 7. The method according to claim 1, characterized in that the value of the increment of the path is determined by the obtained values of the apparent acceleration of movement during the working cycle and / or using the odometric number system of the path according to a deterministic algorithm for calculating the distance traveled. 8. An integrated navigation system for determining the location of moving objects, containing a block of linear acceleration sensors, a block of magnetic field sensors and a receiver of satellite radio navigation systems (SRNS), characterized in that a block of angular velocity sensors, a unit for matching devices according to signal levels, a time storage unit are introduced , an overload sensor, a calibration and digital processing unit, a calculation and control unit, a dead reckoning unit, a digital graphic display and an exchange interface, and the outputs of the date block linear acceleration sensors, a magnetic field sensor unit and an angular velocity sensor unit are connected respectively to the first, second and third inputs of the device matching unit according to signal levels, the first, second and third outputs of which are connected to the corresponding inputs of the calibration and digital processing unit, the first, second and the third outputs of which are connected to the corresponding inputs of the computing and control unit, the fourth output of which is connected to the input of the exchange interface, the output of which is connected to the sixth input of the computing unit education and management; in addition, the output of the linear acceleration sensor unit is connected to the first input of the dead reckoning unit and through the overload sensor with the fourth input of the calculation and control unit, the first output of which is connected to the input of the angular velocity sensor unit, and the second output of the calculation and control unit is connected to the input of the SRNS receiver the first output of which through the time storage unit is connected to the eighth input of the calculation and control unit, and the second output of the SRNS receiver is connected to the seventh input of the calculation and control unit, the third output of which connected to the input of the digital graphic display, and the fifth calculation unit and output control connected to the second input of dead reckoning, an output connected to a fifth input of the computing and control. 9. The system of claim 8, characterized in that the calculation and control unit is configured to determine location coordinates, directional angles of the direction of movement, magnetic and geographical azimuth, range and angles to the control points of the route, the distance traveled and the speed of moving ground objects based on integrated processing of information from linear acceleration sensor blocks, magnetic field sensors and angular velocity sensors, as well as from the SRNS receiver. 10. The system of claim 8, wherein the time storage unit is configured to provide a single time clock, signals for synchronizing objects with a single time, providing constant reference to a single time scale and storing time with high accuracy. 11. The system of claim 8, wherein the calibration and digital processing unit is configured to scale analog signals at a given level and approximate the voltage into a binary code. 12. The system of claim 8, characterized in that the overload sensor is configured to generate a digital alarm (lock) signal to eliminate a second-type ballistic error (acceleration-damping error) of the angular velocity unit for the duration of the error correction, and when working, recovery digital signal of permission of work.

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