Coriolis north seeker and north seeking method thereof

Abstract

The invention relates to the technical field of inertial navigation, and provides a Coriolis north seeker and a north seeking method thereof. The Coriolis effect rotating table is connected with the output end of the rotating motor; the laser transmitter is fixed in position and is used for continuously transmitting laser; the dynamic rotation acceleration sensing unit is fixed with the Coriolis effect rotating table, and the dynamic rotation acceleration sensing unit comprises an acceleration sensor and a laser receiver; and the azimuth angle resolving module is used for receiving an output signal of the acceleration sensor and an output signal of the laser receiver, performing rotation period division by using the output signal of the laser receiver, and resolving according to the output signal of the acceleration sensor in a rotation period to obtain a north azimuth angle. According to the method, azimuth angle calculation is carried out on the rotation full-period data of the acceleration sensor, so that random errors caused by few data sample points can be reduced, and the north-seeking precision is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of inertial navigation, and in particular to a Coriolis north-finder and a north-finder method thereof. Background Art

[0002] North-seeking technology refers to the technology of determining the true north direction of the earth through various devices and methods. Inertial north-seeking technology is one of them, which uses inertial components such as gyroscopes and accelerometers to measure the north component of the earth's rotational angular velocity to determine the true north direction. Inertial devices are not affected by external environmental conditions such as magnetic field interference, weather changes, terrain obstructions and other factors. They have the advantages of long-term stable operation, high accuracy, full autonomy, and short measurement time. They are often used in the initial alignment of missiles, artillery aiming and launching, geophysical exploration, geodesy, coal mining and oil drilling.

[0003] The structure of the gyroscope system is complex, and different types of gyroscopes generally have contradictions between small size, high precision, high efficiency, strong anti-interference and low cost. Therefore, the research of high-precision, small size, high efficiency and low-cost north finder is still an important research topic in the field of inertial navigation.

[0004] In the 1980s, with the advancement of accelerometer manufacturing technology, a non-gyroscopic inertial measurement unit (NIMU) appeared abroad. It abandoned the expensive gyro and used three orthogonally placed and independently rotating accelerometers for north-seeking attitude settlement, which greatly reduced the manufacturing cost. It also adopted a dynamic working mode with fast response speed, avoiding the influence of gyro drift and other factors on orientation accuracy.

[0005] In the 1990s, some domestic scholars proposed a new idea of ​​using accelerometers to replace gyroscopes for north-seeking. Accelerometer north-seeking adopts a dynamic north-seeking method with potential advantages of fast response speed, high accuracy and low cost. In recent years, research on accelerometer north-seeking has gradually increased.

[0006] The existing accelerometer north-finding solution is to place the accelerometer symmetrically on a connecting rod symmetrical structure turntable, with the sensitive axis of the accelerometer pointing vertically upward. The connecting rod structure turntable moves at a uniform speed driven by a motor, and the accelerometer measures the absolute acceleration at four reference points to calculate the azimuth angle.

[0007] The existing accelerometer north finder uses the four-position method for dynamic north finding. The number of data sample points is small and the single-point data is highly random. The random error of a single position accumulates with the increase of data volume, thus affecting the accuracy of north finding. The use of a connecting rod split structure will produce large vibrations when rotating at high speed, reducing the signal-to-noise ratio of useful signals. In addition, the existing device uses conductive rings and servo motors, which inevitably lead to large size, high power consumption, and difficulty in carrying. Summary of the invention

[0008] In view of the deficiencies in the prior art, the present invention provides a Coriolis north-finding instrument and a north-finding method thereof, aiming to solve at least some of the technical problems existing in the prior art.

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] In one aspect, the present invention provides a Coriolis north finder, comprising:

[0011] Rotating electrical machines;

[0012] A Coriolis effect rotating table, which is connected to the output end of the rotating motor and performs a rotating motion driven by the rotating motor;

[0013] A laser transmitter, which is fixed in position and used for continuously emitting laser light;

[0014] A dynamic rotation acceleration sensing unit, which is fixed to the Coriolis effect rotating table, and includes an acceleration sensor and a laser receiver, wherein the acceleration sensor is used to sense acceleration and output a signal; when the Coriolis effect rotating table rotates to a certain position, the laser receiver is directly opposite to the laser transmitter, and the laser receiver is used to generate a high level and output a signal after receiving the laser signal;

[0015] The azimuth angle calculation module is used to receive the output signal of the acceleration sensor and the output signal of the laser receiver, divide the rotation period by the output signal of the laser receiver, and calculate the north azimuth according to the output signal of the acceleration sensor within one rotation period.

[0016] Preferably, the rotating motor is a hollow shaft motor, the output end of which is a hollow rotor, and a lower half shaft is extended from the lower end surface of the Coriolis effect rotating table, and the lower half shaft is inserted into the hollow rotor and fixed.

[0017] Preferably, an upper semi-shaft is extended from the upper end surface of the Coriolis effect rotating table, and the top of the upper semi-shaft is connected to a fixed platform via a bearing.

[0018] Preferably, the laser transmitter is fixed to the bottom of the fixed platform, and the laser transmitter and the laser receiver are at the same distance from the central axis of the Coriolis effect rotating table.

[0019] Preferably, the laser receiver is located at the midpoint of a line connecting the center of the Coriolis effect rotating table and the center of the acceleration sensor.

[0020] Preferably, the Coriolis effect rotating platform and the dynamic rotation acceleration sensing unit are both disc-shaped and coaxially bonded together.

[0021] Preferably, it also includes an azimuth display unit, which is used to receive and display the north azimuth data calculated by the azimuth solving module.

[0022] Preferably, the dynamic rotational acceleration sensing unit also includes a non-contact signal transmission module, and the azimuth display unit includes a non-contact signal receiving module, a main control chip and a display screen. The non-contact signal transmission module transmits the north azimuth data calculated by the azimuth calculation module to the non-contact signal receiving module, and the non-contact signal receiving module transmits the north azimuth data to the main control chip for processing and then displays it on the display screen.

[0023] On the other hand, the present invention further provides a Coriolis north-finding method, using the Coriolis north-finding instrument as described in any one of the above items, the method comprising:

[0024] The rotating motor drives the Coriolis effect rotating table to rotate at a preset speed;

[0025] Synchronously collect the output signal of the acceleration sensor and the output signal of the laser receiver;

[0026] The output signal of the laser receiver is used to divide the rotation period, and the north azimuth is calculated based on the output signal of the acceleration sensor within one rotation period.

[0027] Preferably, the step of calculating the north azimuth according to the output signal of the acceleration sensor within one rotation cycle specifically includes:

[0028] (1) According to the principle of acceleration synthesis, the north-seeking equation of the acceleration sensor is determined:

[0029] a=-g+a0+2Ωrω N cos(Ωt+θ)

[0030] a is the output signal of the acceleration sensor, g is the gravitational acceleration, a0 is the zero bias of the acceleration sensor, Ω is the angular velocity of the Coriolis effect turntable, r is the distance from the sensitive axis of the acceleration sensor to the axis of the Coriolis effect turntable, ω N =ωcosφ is the north component of the earth's rotation angular velocity at that location, ω is the earth's rotation angular velocity, φ is the latitude of the location of the Coriolis effect rotating platform, and θ is the north azimuth; g and a0 are constants;

[0031] According to the trigonometric function and the difference angle formula, the above formula is transformed into the following form:

[0032] a=q1sinΩt+q2cosΩt+q3

[0033] Where: q1 = -2Ωrω N sinθ,q2=2Ωrω N cosθ,q3=-g + a0

[0034] The mathematical model of the acceleration sensor output signal is constructed as follows:

[0035] a i =q1sinΩt i +q2cosΩt i +q3 (i=1,2,3,…,n)

[0036] Among them, a i is the output signal of the acceleration sensor corresponding to the i-th sampling point, Ωt i is the angle of rotation of the Coriolis effect rotating stage at the i-th sampling point;

[0037] (2) Take n groups of acceleration sensor output signals in the same rotation cycle to construct a set of equations:

[0038]

[0039] Construct a matrix from a system of equations:

[0040]

[0041] Solving the equation gives the values ​​of q1, q2, and q3.

[0042] (3) Establish the azimuth angle solution equation:

[0043]

[0044] The north azimuth θ can be calculated.

[0045] In summary, the present invention has the following beneficial effects compared with the prior art:

[0046] The present invention generates a periodic signal by the cooperation of a laser transmitter and a laser receiver, divides the rotation period by the output signal of the laser receiver, and calculates the north azimuth according to the output signal of the acceleration sensor within one rotation period. By calculating the azimuth of the full rotation period data of the acceleration sensor, the random error caused by the small number of data sample points can be reduced, thereby greatly improving the north-seeking accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A structural diagram of a Coriolis north finder provided in this embodiment;

[0048] Figure 2 A schematic diagram of a dynamic rotation acceleration sensing unit provided in this embodiment;

[0049] Figure 3 A schematic diagram of an azimuth angle display unit provided in this embodiment;

[0050] Figure 4 The Coriolis north-seeking principle diagram provided for this embodiment. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0052] Embodiment 1:

[0053] like Figures 1 to 3 As shown, an embodiment of the present invention provides a Coriolis north finder, comprising:

[0054] A rotating electrical machine 1 having a speed output terminal;

[0055] A Coriolis effect rotating table 2, which is connected to the output end of the rotating motor 1 and performs a rotating motion driven by the rotating motor 1;

[0056] A laser transmitter 4, which is fixed in position and used to transmit laser light of a specific frequency;

[0057] A dynamic rotation acceleration sensing unit 3, which is fixed to the Coriolis effect rotating table 2 and rotates with the Coriolis effect rotating table. The dynamic rotation acceleration sensing unit 3 includes an acceleration sensor 301 and a laser receiver 306. The acceleration sensor 301 is used to sense acceleration and output a signal. When the Coriolis effect rotating table 2 rotates to a certain position, the laser receiver 306 is directly opposite to the laser transmitter 4. At this time, the laser receiver 306 can receive the laser signal emitted by the laser transmitter 4. The laser receiver 306 is used to generate a high level and output a signal after receiving the laser signal. Since the position of the laser transmitter 4 is fixed, only the laser receiver 306 rotates. The laser receiver 306 receives a laser signal once per rotation cycle, that is, each time the laser receiver 306 generates an output signal, it represents that the Coriolis effect rotating table 2 rotates one circle, so that the rotation cycle can be divided;

[0058] The azimuth angle calculation module 302 is used to receive the output signal of the acceleration sensor 301 and the output signal of the laser receiver 306, divide the rotation period by the output signal of the laser receiver 306, and calculate the north azimuth according to the output signal of the acceleration sensor 301 within a rotation period.

[0059] The present invention generates a periodic signal by the cooperation of a laser transmitter and a laser receiver, divides the rotation period by the output signal of the laser receiver 306, and calculates the north azimuth according to the output signal of the acceleration sensor 301 within one rotation period. By calculating the azimuth of the full rotation period data of the acceleration sensor 301, the random error caused by the small number of data sample points can be reduced, thereby greatly improving the north-seeking accuracy.

[0060] Specifically, the rotating motor 1 is a hollow shaft motor, and its output end is a hollow rotor. The Coriolis effect rotating table 2 is disc-shaped, and the upper and lower half shafts are respectively extended and arranged at the center positions of the upper and lower end surfaces thereof, and the upper and lower half shafts are preferably arranged integrally with the Coriolis effect rotating table 2. The lower half shaft is inserted into the hollow rotor and fixed, so that the Coriolis effect rotating table 2 rotates under the drive of the hollow rotor. By inserting the lower half shaft of the Coriolis effect rotating table 2 into the hollow rotor of the rotating motor 1 and fixing it, the rotating shaft of the rotating motor 1 is omitted, and the connection between the two is more stable, and the overall structure is more compact.

[0061] Preferably, a fixed platform is further included, a bearing hole is provided at the bottom of the fixed platform, a bearing 5 is provided in the bearing hole, an outer ring of the bearing 5 is fixed to the inner wall of the bearing hole, the top of the upper half shaft of the Coriolis effect rotating table 2 extends into the inner ring of the bearing and is fixed, and the top of the upper half shaft is connected to the fixed platform through the bearing 5, which does not affect the rotation of the Coriolis effect rotating table 2 and can limit the Coriolis effect rotating table 2 to a certain extent, so that it is more stable during rotation and reduces vibration, effectively improving the signal-to-noise ratio of the output signal of the acceleration sensor 301 under high speed conditions, thereby making the subsequent azimuth angle solution more accurate.

[0062] In this embodiment, the laser emitter 4 is fixed to the bottom of the fixed platform, and the laser emitter 4 and the laser receiver 306 are at the same distance from the central axis of the Coriolis effect rotating table 2, so as to ensure that when the Coriolis effect rotating table 2 rotates to a certain position, the laser receiver 306 is directly opposite to the laser emitter 4. In other embodiments, the laser emitter 4 can also be fixed to other positions, as long as it can ensure that when the Coriolis effect rotating table 2 rotates to a certain position, the laser receiver 306 can receive the laser emitted by the laser emitter 4.

[0063] Preferably, the laser receiver 306 is located at the midpoint of a line connecting the center of the Coriolis effect rotating platform 2 and the center of the acceleration sensor 301 to avoid mutual influence between components.

[0064] Preferably, the dynamic rotation acceleration sensing unit 3 is also disc-shaped as a whole and is coaxially attached to the Coriolis effect rotating table 2. The middle of the dynamic rotation acceleration sensing unit 3 has a clearance hole for the upper half axis of the Coriolis effect rotating table 2 to pass through. Preferably, the dynamic rotation acceleration sensing unit 3 also includes a non-contact signal transmission module 303, a data acquisition module 305 and a button battery 304. The non-contact signal transmission module 303 is used to transmit data. The data acquisition module 305 is preferably a high-speed precision ADC module for synchronously acquiring the output signal of the acceleration sensor 301 and the output signal of the laser receiver 306; the button battery 304 is used to power the dynamic rotation acceleration sensing unit 3. Preferably, the azimuth angle resolution module 302 can also be integrated into the dynamic rotation acceleration sensing unit, so that the azimuth angle resolution can be completed in the device without external processing, which greatly improves the efficiency of north-seeking. More preferably, the acceleration sensor 301, button battery 304 and data acquisition module 305 are provided in two groups and are symmetrically arranged, so that the mass of the dynamic rotation acceleration sensing unit is balanced, the vibration generated during movement is reduced, and the north-seeking accuracy is improved.

[0065] Preferably, it also includes an azimuth display unit 6, which is used to receive and display the north azimuth data obtained by the azimuth solution module. The azimuth display unit 6 includes a non-contact signal receiving module 605, a main control chip 602, a display screen 601, a switch 603 and a battery compartment 604. The non-contact signal transmission module 303 transmits the north azimuth data obtained by the azimuth solution module to the non-contact signal receiving module 605. The non-contact signal receiving module 605 transmits the north azimuth data to the main control chip 602 for processing and then displays it on the display screen 601. The non-contact signal transmission method is adopted, and the signal transmission is more convenient, the connecting wire is omitted, and the structure of the north finder is optimized. The azimuth display unit 6 is located on the fixed platform, and the whole device is integrated.

[0066] Example 2

[0067] The embodiment of the present invention further provides a Coriolis north-finding method, using the Coriolis north-finding instrument described in the above embodiment 1, the method comprising:

[0068] The rotating motor drives the Coriolis effect rotating table to rotate at a preset rotating speed, and the rotating speed is adjustable;

[0069] The azimuth angle calculation module controls the data acquisition module to synchronously collect the output signal of the acceleration sensor and the output signal of the laser receiver;

[0070] The output signal of the laser receiver is used to divide the rotation period, and the north azimuth is calculated based on the output signal of the acceleration sensor within one rotation period.

[0071] Preferably, the step of calculating the north azimuth according to the output signal of the acceleration sensor within one rotation cycle specifically includes:

[0072] (1) According to the principle of acceleration synthesis, the north-seeking equation of the acceleration sensor is determined:

[0073] a=-g+a0+2Ωrω N cos(Ωt+θ)

[0074] a is the output signal of the acceleration sensor, g is the gravitational acceleration, a0 is the zero bias of the acceleration sensor, Ω is the angular velocity of the Coriolis effect turntable, in degrees / second or radians / second, r is the distance from the sensitive axis of the acceleration sensor to the axis of the Coriolis effect turntable, ω N =ωcosφ is the north component of the earth's rotation angular velocity at that location, ω is the earth's rotation angular velocity, φ is the latitude of the location of the Coriolis effect rotating platform, and θ is the north azimuth; g and a0 are constants;

[0075] According to the trigonometric function and the difference angle formula, the above formula is transformed into the following form:

[0076] a=q1sinΩt+q2cosΩt+q3

[0077] Where: q1 = -2Ωrω N sinθ,q2=2Ωrω N cosθ,q3=-g+a0

[0078] The mathematical model of the acceleration sensor output signal is constructed as follows:

[0079] a i =q1sinΩt i +q2cosΩt i +q3 (i=1,2,3,…,n)

[0080] Among them, t is time in seconds; i is the mathematical model sampling point, and one sampling point i corresponds to one time t i ; a i is the output signal of the acceleration sensor corresponding to the i-th sampling point, Ωt i is the angle rotated by the Coriolis effect rotating stage at the i-th sampling point; the meanings of other letters are the same as above.

[0081] (2) Take n groups of acceleration sensor output signals in the same rotation cycle to construct a set of equations:

[0082]

[0083] Construct a matrix from a system of equations:

[0084]

[0085] Solving the equation gives the values ​​of q1, q2, and q3.

[0086] (3) Establish the azimuth angle solution equation:

[0087]

[0088] The north azimuth θ can be calculated.

[0089] The north-seeking method of the present invention simplifies the north-seeking equation. By solving the azimuth angle of the full-cycle data of the acceleration sensor rotation, the random error caused by the small number of data sample points can be reduced, and the north-seeking accuracy is greatly improved. The north-seeking method of the present invention can complete the azimuth angle solution in the device without external processing, which greatly improves the north-seeking efficiency. Moreover, the solution can be performed when the device is turned on, and can be used in real time.

[0090] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer-usable program code.

[0091] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0092] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0093] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0094] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A Coriolis north finder, characterized in that: include: Rotating electrical machines; A Coriolis effect rotating table, which is connected to the output end of the rotating motor and performs a rotating motion driven by the rotating motor; A laser transmitter, which is fixed in position and used for continuously emitting laser light; A dynamic rotation acceleration sensing unit, which is fixed to the Coriolis effect rotating table, and includes an acceleration sensor and a laser receiver, wherein the acceleration sensor is used to sense acceleration and output a signal; when the Coriolis effect rotating table rotates to a certain position, the laser receiver is directly opposite to the laser transmitter, and the laser receiver is used to generate a high level and output a signal after receiving the laser signal; The azimuth angle calculation module is used to receive the output signal of the acceleration sensor and the output signal of the laser receiver, divide the rotation period by the output signal of the laser receiver, and calculate the north azimuth according to the output signal of the acceleration sensor within one rotation period.

2. A Coriolis north finder as claimed in claim 1, characterized in that: The rotating motor is a hollow shaft motor, and its output end is a hollow rotor. A lower half shaft is extended from the lower end surface of the Coriolis effect rotating table, and the lower half shaft is inserted into the hollow rotor and fixed.

3. A Coriolis north finder as claimed in claim 1, characterized in that: An upper half shaft is extended from the upper end surface of the Coriolis effect rotating platform, and the top of the upper half shaft is connected to a fixed platform through a bearing.

4. A Coriolis north finder as claimed in claim 3, characterized in that: The laser transmitter is fixed to the bottom of the fixed platform, and the laser transmitter and the laser receiver are at the same distance from the central axis of the Coriolis effect rotating stage.

5. A Coriolis north finder as claimed in claim 1, characterized in that: The laser receiver is located at the midpoint of a line connecting the center of the Coriolis effect rotating platform and the center of the acceleration sensor.

6. A Coriolis north finder as claimed in claim 1, characterized in that: The Coriolis effect rotating platform and the dynamic rotating acceleration sensing unit are both disc-shaped and coaxially attached together.

7. A Coriolis north finder as claimed in claim 1, characterized in that: It also includes an azimuth display unit, which is used to receive and display the north azimuth data calculated by the azimuth calculation module.

8. A Coriolis north finder as claimed in claim 7, characterized in that: The dynamic rotation acceleration sensing unit also includes a non-contact signal transmission module, and the azimuth display unit includes a non-contact signal receiving module, a main control chip and a display screen. The non-contact signal transmission module transmits the north azimuth data calculated by the azimuth calculation module to the non-contact signal receiving module, and the non-contact signal receiving module transmits the north azimuth data to the main control chip for processing and then displays it on the display screen.

9. A Coriolis north-finding method, using the Coriolis north-finding instrument as claimed in any one of claims 1 to 8, characterized in that: The method includes: The rotating motor drives the Coriolis effect rotating table to rotate at a preset speed; Synchronously collect the output signal of the acceleration sensor and the output signal of the laser receiver; The output signal of the laser receiver is used to divide the rotation period, and the north azimuth is calculated based on the output signal of the acceleration sensor within one rotation period.

10. A Coriolis north-finding method as claimed in claim 9, characterized in that: The method of calculating the north azimuth according to the output signal of the acceleration sensor within one rotation cycle specifically includes: (1) According to the principle of acceleration synthesis, the north-seeking equation of the acceleration sensor is determined: a=-g+a0+2Ωrω N cos(Ωt+θ) a is the output signal of the acceleration sensor, g is the gravitational acceleration, a0 is the zero bias of the acceleration sensor, Ω is the angular velocity of the Coriolis effect turntable, r is the distance from the sensitive axis of the acceleration sensor to the axis of the Coriolis effect turntable, ω N =ωcosφ is the north component of the earth's rotation angular velocity at that location, ω is the earth's rotation angular velocity, φ is the latitude of the location of the Coriolis effect rotating platform, and θ is the north azimuth; g and a0 are constants; According to the trigonometric function and the difference angle formula, the above formula is transformed into the following form: a=q1sinΩt+q2cosΩt+q3 where: q1 = -2Ωrω N sinθ, q2 = 2Ωrω N cosθ, q3 = -g + a0 The mathematical model of the acceleration sensor output signal is constructed as follows: a i =q1sinΩt i +q2cosΩt i +q3(i=1,2,3,…,n) Among them, a i is the output signal of the acceleration sensor corresponding to the i-th sampling point, Ωt i is the angle of rotation of the Coriolis effect rotating stage at the i-th sampling point; (2) Take n groups of acceleration sensor output signals in the same rotation cycle to construct a set of equations: Construct a matrix from a system of equations: Solving the equation gives the values ​​of q1, q2, and q3. (3) Establish the azimuth angle solution equation: The north azimuth θ can be calculated.

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