阅读说明：本技术 一种寻北装置 (North seeking device ) 是由 赵子豪 杨晨光 邢成 薛兵 侯泽 庄灿涛 于 2020-04-22 设计创作，主要内容包括：本说明书一个或多个实施例提供一种寻北装置,包括：粗寻北单元、光纤陀螺仪、转台机构、驱动单元及数据处理单元：数据处理单元包括：判断模块,用于根据获取的所述粗寻北单元的方位输出信号,判断所述光纤陀螺仪是否位于非误差角度位置；控制模块,用于当判断所述光纤陀螺仪位于非误差角度位置时,控制所述驱动单元动作,以使所述转台机构带动所述光纤陀螺仪转动至预定位置；倾角计算模块,用于根据获取的所述光纤陀螺仪位于预定位置时的输出信号,计算得到第一倾角结果。本实施例的寻北装置能够实现高精度寻北。(One or more embodiments of the present specification provide a north-seeking apparatus, including: the rough north-seeking unit, the optical fiber gyroscope, the turntable mechanism, the driving unit and the data processing unit: the data processing unit includes: the judging module is used for judging whether the optical fiber gyroscope is located at a non-error angle position according to the acquired azimuth output signal of the rough north-seeking unit; the control module is used for controlling the driving unit to act when the optical fiber gyroscope is judged to be located at a non-error angle position, so that the rotary table mechanism drives the optical fiber gyroscope to rotate to a preset position; and the inclination angle calculation module is used for calculating to obtain a first inclination angle result according to the acquired output signal when the optical fiber gyroscope is positioned at the preset position. The north-seeking device of the embodiment can realize high-precision north seeking.)

1. A north-seeking apparatus, comprising: the rough north-seeking unit, the optical fiber gyroscope, the turntable mechanism, the driving unit and the data processing unit: the data processing unit includes:

the judging module is used for judging whether the optical fiber gyroscope is located at a non-error angle position according to the acquired azimuth output signal of the rough north-seeking unit;

the control module is used for controlling the driving unit to act when the optical fiber gyroscope is judged to be located at a non-error angle position, so that the rotary table mechanism drives the optical fiber gyroscope to rotate to a preset position;

and the inclination angle calculation module is used for calculating to obtain a first inclination angle result according to the acquired output signal when the optical fiber gyroscope is positioned at the preset position.

2. The north-seeking apparatus according to claim 1, wherein the data processing unit further comprises:

the judging module is used for judging whether the optical fiber gyroscope is positioned in an error angle position range according to the acquired azimuth output signal of the rough north-seeking unit;

the control module is used for controlling the driving unit to act when the optical fiber gyroscope is judged to be located in the error angle position range, so that the rotary table mechanism drives the optical fiber gyroscope to rotate by a preset angle to reach a non-error angle position; after the optical fiber gyroscope is located at a non-error angle position, controlling the driving unit to act so that the turntable mechanism drives the optical fiber gyroscope to rotate to a preset position;

and the inclination angle calculation module is used for calculating to obtain an inclination angle result according to the acquired output signal when the optical fiber gyroscope is positioned at the preset position, and determining a second inclination angle result according to the inclination angle result and the preset angle.

3. The north seeker of claim 1, wherein the tilt calculation module calculates the first tilt result by:

wherein S is the first inclination angle result, P_1iWhen the optical fiber gyroscope rotates to a first preset position, obtaining an output signal P of the optical fiber gyroscope at the ith time_2iWhen the optical fiber gyroscope rotates to a second preset position, obtaining the output signal of the optical fiber gyroscope at the ith time, P_3iWhen the optical fiber gyroscope rotates to a third preset position, obtaining an output signal P of the optical fiber gyroscope at the ith time_4iThe number m is the total number of times of the output signal of the optical fiber gyroscope acquired when the optical fiber gyroscope rotates to the preset position.

4. The north-seeking apparatus according to claim 1, wherein the apparatus further comprises an optical encoder, and the data processing unit further comprises:

and the position judging module is used for judging whether the optical fiber gyroscope reaches the preset position or not according to the acquired output signal of the photoelectric encoder.

5. The north-seeking arrangement according to claim 4,

the position judging module is used for determining a first rotation angle of the driving unit according to the acquired rotation parameters of the photoelectric encoder, determining a second rotation angle of the driving unit according to the driving parameters of the driving unit and control parameters corresponding to the driving unit to control the optical fiber gyroscope to reach the preset position, judging whether the first rotation angle and the second rotation angle are equal, and if so, judging that the optical fiber gyroscope reaches the preset position.

6. The north-seeking device according to claim 1, wherein the device further comprises a MEMS tilt sensor, the data processing unit further comprising:

and the inclination angle calculation module is used for calculating an inclination angle result according to the output signal of the MEMS inclination angle sensor when the acquired optical fiber gyroscope is positioned at a preset position.

7. The north-seeking apparatus according to claim 6, wherein the tilt angle calculation module calculates the tilt angle result by:

wherein β is the tilt angle of the MEMS tilt sensor with respect to the horizontal direction, L is the total number of output signals of the MEMS tilt sensor obtained when the optical fiber gyroscope is located at a predetermined position, Y_jThe output signal of the MEMS tilt angle sensor in the Y-axis direction is X when the optical fiber gyroscope is positioned at the j preset position_jAnd outputting a signal of the MEMS tilt angle sensor in the X-axis direction when the optical fiber gyroscope is located at the j preset position.

8. The north seeker according to claim 1, wherein the north seeker includes a base plate, a first support plate, a turntable, a second support plate, a photoelectric encoder, a slip ring, and an upper cover, the base plate is connected to the first support plate via a support, an output shaft of the drive unit is connected to an input end of a reducer, the reducer is fixed to one side of the first support plate, the photoelectric encoder is fixed to the other side of the first support plate, a grating plate of the photoelectric encoder is coaxially connected to an output shaft of the reducer, one side of the turntable is connected to an output shaft end face of the reducer, the other side of the turntable is connected to one side of the second support plate via a fixing bracket, and the optical fiber gyroscope is fixed to the fixing bracket; one end of the slip ring is connected with the other side of the second supporting plate, signal output ends of the optical fiber gyroscope and the photoelectric encoder are connected with a data input end of the data processing unit through the slip ring, a control signal end of the data processing unit is connected with a control end of the driving unit through the slip ring, the data processing unit is realized based on a circuit board, and the circuit board is fixedly connected with the upper cover.

9. The north seeker of claim 8 further comprising an outer cylinder, wherein the outer cylinder is fixedly connected with the bottom plate and the upper cover in a sealing manner.

10. The north-seeking apparatus according to claim 2, wherein the data processing unit further comprises:

the time service module is used for providing time service time;

and the storage module is used for storing the first inclination angle result or the second inclination angle result according to the time format of the time service time.

Technical Field

One or more embodiments of the present disclosure relate to the field of observation instrument technology, and more particularly, to a north seeker.

Background

The north-seeking device is a high-precision inertial instrument capable of automatically indicating the direction, and is widely applied to the engineering measurement fields of mines, railways, aerospace, military and the like. The north-seeking device based on the optical fiber gyroscope is influenced by the design process of the gyroscope, and when the inclination angle of the optical fiber gyroscope relative to the due north direction is within the error angle position range, a zero error is generated, so that the measurement precision of the north-seeking device is influenced.

Disclosure of Invention

In view of the above, one or more embodiments of the present disclosure are directed to a north seeker capable of improving the measurement accuracy of the north seeker.

In view of the above, one or more embodiments of the present specification provide a north seeking apparatus, including: the rough north-seeking unit, the optical fiber gyroscope, the turntable mechanism, the driving unit and the data processing unit: the data processing unit includes:

the judging module is used for judging whether the optical fiber gyroscope is located at a non-error angle position according to the acquired azimuth output signal of the rough north-seeking unit;

the control module is used for controlling the driving unit to act when the optical fiber gyroscope is judged to be located at a non-error angle position, so that the rotary table mechanism drives the optical fiber gyroscope to rotate to a preset position;

and the inclination angle calculation module is used for calculating to obtain a first inclination angle result according to the acquired output signal when the optical fiber gyroscope is positioned at the preset position.

Optionally, the data processing unit further includes:

the judging module is used for judging whether the optical fiber gyroscope is positioned in an error angle position range according to the acquired azimuth output signal of the rough north-seeking unit;

the control module is used for controlling the driving unit to act when the optical fiber gyroscope is judged to be located in the error angle position range, so that the rotary table mechanism drives the optical fiber gyroscope to rotate by a preset angle to reach a non-error angle position; after the optical fiber gyroscope is located at a non-error angle position, controlling the driving unit to act so that the turntable mechanism drives the optical fiber gyroscope to rotate to a preset position;

and the inclination angle calculation module is used for calculating to obtain an inclination angle result according to the acquired output signal when the optical fiber gyroscope is positioned at the preset position, and determining a second inclination angle result according to the inclination angle result and the preset angle.

Optionally, the method for calculating the first inclination result by the inclination calculation module is as follows:

wherein S is the first inclination angle result, P_1iWhen the optical fiber gyroscope rotates to a first preset position, obtaining an output signal P of the optical fiber gyroscope at the ith time_2iWhen the optical fiber gyroscope rotates to a second preset position, obtaining the output signal of the optical fiber gyroscope at the ith time, P_3iWhen the optical fiber gyroscope rotates to a third preset position, obtaining an output signal P of the optical fiber gyroscope at the ith time_4iThe number m is the total number of times of the output signal of the optical fiber gyroscope acquired when the optical fiber gyroscope rotates to the preset position.

Optionally, the apparatus further includes a photoelectric encoder, and the data processing unit further includes:

and the position judging module is used for judging whether the optical fiber gyroscope reaches the preset position or not according to the acquired output signal of the photoelectric encoder.

Optionally, the position determining module is configured to determine a first rotation angle of the driving unit according to the acquired rotation parameter of the optical encoder, determine a second rotation angle of the driving unit according to the driving parameter of the driving unit and a control parameter corresponding to controlling the driving unit to move so that the optical fiber gyroscope reaches the predetermined position, determine whether the first rotation angle and the second rotation angle are equal, and if so, determine that the optical fiber gyroscope reaches the predetermined position.

Optionally, the apparatus further includes a MEMS tilt sensor, and the data processing unit further includes:

and the inclination angle calculation module is used for calculating an inclination angle result according to the output signal of the MEMS inclination angle sensor when the acquired optical fiber gyroscope is positioned at a preset position.

Optionally, the method for calculating the tilt angle result by the tilt angle calculation module is as follows:

wherein β is the tilt angle of the MEMS tilt sensor with respect to the horizontal direction, L is the total number of output signals of the MEMS tilt sensor obtained when the optical fiber gyroscope is located at a predetermined position, Y_jThe output signal of the MEMS tilt angle sensor in the Y-axis direction is X when the optical fiber gyroscope is positioned at the j preset position_jAnd outputting a signal of the MEMS tilt angle sensor in the X-axis direction when the optical fiber gyroscope is located at the j preset position.

Optionally, the device comprises a bottom plate, a first supporting plate, a rotary table, a second supporting plate, a photoelectric encoder, a slip ring and an upper cover, wherein the bottom plate is connected with the first supporting plate through a support column, an output shaft of the driving unit is connected with an input end of a speed reducer, the speed reducer is fixed on one side of the first supporting plate, the photoelectric encoder is fixed on the other side of the first supporting plate, a grating disc of the photoelectric encoder is coaxially connected with an output shaft of the speed reducer, one side of the rotary table is connected with an output shaft end face of the speed reducer, the other side of the rotary table is connected with one side of the second supporting plate through a fixing frame, and the optical fiber gyroscope is fixed on the fixing frame; one end of the slip ring is connected with the other side of the second supporting plate, signal output ends of the optical fiber gyroscope and the photoelectric encoder are connected with a data input end of the data processing unit through the slip ring, a control signal end of the data processing unit is connected with a control end of the driving unit through the slip ring, the data processing unit is realized based on a circuit board, and the circuit board is fixedly connected with the upper cover.

Optionally, the north-seeking device further comprises an outer cylinder, and the outer cylinder is fixedly connected with the bottom plate and the upper cover in a sealing manner.

Optionally, the data processing unit further includes:

the time service module is used for providing time service time;

and the storage module is used for storing the first inclination angle result or the second inclination angle result according to the time format of the time service time.

As can be seen from the above description, the north-seeking apparatus provided in one or more embodiments of the present specification includes a coarse north-seeking unit, an optical fiber gyroscope, a turntable mechanism, a driving unit, and a data processing unit, where the data processing unit includes a determining module, configured to determine whether the optical fiber gyroscope is located at a non-error angular position according to an obtained azimuth output signal of the coarse north-seeking unit; the control module is used for controlling the driving unit to act when the optical fiber gyroscope is judged to be located at the non-error angle position, so that the rotary table mechanism drives the optical fiber gyroscope to rotate to a preset position; and the inclination angle calculation module is used for calculating to obtain a first inclination angle result according to the acquired output signal when the optical fiber gyroscope is positioned at the preset position. The north-seeking device of the embodiment can realize high-precision north seeking.

Drawings

In order to more clearly illustrate one or more embodiments or prior art solutions of the present specification, the drawings that are needed in the description of the embodiments or prior art will be briefly described below, and it is obvious that the drawings in the following description are only one or more embodiments of the present specification, and that other drawings may be obtained by those skilled in the art without inventive effort from these drawings.

FIG. 1 is a schematic perspective view of an apparatus according to one or more embodiments of the present disclosure;

FIGS. 2A, 2B and 2C are schematic views of the device shown in FIG. 1 with different angles;

FIG. 3 is a schematic diagram of an apparatus according to one or more embodiments of the present disclosure;

FIG. 4 is a block diagram of a data processing unit according to one or more embodiments of the present disclosure;

fig. 5 is a block diagram of a data processing unit according to another embodiment of the present disclosure.

Detailed Description

For the purpose of promoting a better understanding of the objects, aspects and advantages of the present disclosure, reference is made to the following detailed description taken in conjunction with the accompanying drawings.

It is to be noted that unless otherwise defined, technical or scientific terms used in one or more embodiments of the present specification should have the ordinary meaning as understood by those of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in one or more embodiments of the specification is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

As shown in fig. 1 to 4, one or more embodiments of the present specification provide a north seeking apparatus including a coarse north seeking unit, an optical fiber gyro 8, a turntable mechanism, a driving unit 3, and a data processing unit, the data processing unit including:

the judging module is used for judging whether the optical fiber gyroscope 8 is located at a non-error angle position according to the acquired azimuth output signal of the coarse north-seeking unit;

the control module is used for controlling the driving unit 3 to act when the optical fiber gyroscope 8 is judged to be located at the non-error angle position, so that the turntable mechanism drives the optical fiber gyroscope 8 to rotate to a preset position;

and the inclination angle calculation module is used for calculating to obtain a first inclination angle result according to the acquired output signal when the optical fiber gyroscope 8 is located at the preset position.

In this embodiment, data processing unit acquires the azimuth output signal of the unit of seeking north roughly, judge whether the module judges fiber gyroscope 8 to be located non-error angular position according to azimuth output signal, if, confirm that fiber gyroscope 8 can not produce zero error in this position, control module control drive unit 3 acts, 3 drive revolving stage mechanisms of drive unit rotate, drive fiber gyroscope 8 and rotate to preset position, when fiber gyroscope 8 rotates to preset position, inclination calculation module is according to fiber gyroscope 8's output signal, calculate first inclination result, zero error does not exist in the computational result, can realize that the high accuracy seeks north.

In some embodiments, zero errors may be generated when the inclination angle of the optical fiber gyroscope with respect to the north direction is within the ranges of 345 ° to 360 ° and 0 ° to 15 °, so that the inclination angle of the optical fiber gyroscope with respect to the north direction is within the ranges of 345 ° to 360 ° and 0 ° to 15 ° as an error angular position range, the coarse north-seeking unit is first used to acquire the azimuth output signal of the optical fiber gyroscope 8, and if it is determined that the optical fiber gyroscope 8 is not within the error angular position range according to the azimuth output signal of the coarse north-seeking unit, the optical fiber gyroscope 8 is located at a non-error angular position, and in the non-error angular position, no zero error is generated, and the north-seeking result may be determined based on the current position calculation. Alternatively, the rough north-seeking unit may use an instrument such as the electronic compass 14 that can detect the azimuth.

In this embodiment, the calculation method for calculating the first tilt result by the tilt calculation module according to the obtained output signal of the optical fiber gyroscope at the predetermined position includes:

wherein S is a first inclination result, i.e. an inclination of the optical fiber gyroscope 8 with respect to the true north direction (or an included angle between the north-seeking device and the geographic north pole), P_1iThe ith acquired output signal, P, of the optical fiber gyroscope 8 when the optical fiber gyroscope 8 rotates to the first predetermined position_2iThe output signal P of the optical fiber gyroscope 8 acquired at the i-th time when the optical fiber gyroscope 8 rotates to the second predetermined position_3iThe output signal P of the optical fiber gyroscope 8 acquired at the i-th time when the optical fiber gyroscope 8 rotates to the third predetermined position_4iWhen the optical fiber gyroscope 8 rotates to the fourth preset position, the output signal of the optical fiber gyroscope 8 acquired at the ith time, and m is the total number of times of the output signal of the optical fiber gyroscope 8 acquired when the optical fiber gyroscope 8 rotates to the preset position.

In some embodiments, the first tilt angle result is calculated based on a four-position north-seeking algorithm of the optical fiber gyroscope, wherein the optical fiber gyroscope is located at four positions separated by 90 degrees from the first predetermined position, the second predetermined position, the third predetermined position, and the fourth predetermined position, namely, positions corresponding to Φ, Φ +90 °, Φ +180 °, Φ +270 °, respectively.

In some embodiments, the data processing unit further comprises:

the judging module is used for judging whether the optical fiber gyroscope 8 is positioned in the error angle position range according to the acquired azimuth output signal of the coarse north-seeking unit;

the control module is used for controlling the driving unit 3 to act when the optical fiber gyroscope 8 is judged to be positioned in the error angle position range, so that the turntable mechanism drives the optical fiber gyroscope 8 to rotate by a preset angle to reach a non-error angle position; when the optical fiber gyroscope 8 is located at the non-error angle position, the driving unit 3 is controlled to act, so that the turntable mechanism drives the optical fiber gyroscope 8 to rotate to a preset position;

and the inclination angle calculation module is used for calculating an inclination angle result according to the acquired output signal when the optical fiber gyroscope 8 is located at the preset position, and determining a second inclination angle result according to the inclination angle result and the preset angle.

In this embodiment, the data processing unit obtains an azimuth output signal of the rough north-seeking unit, the determining module determines whether the optical fiber gyroscope 8 is located in the error angle position range according to the azimuth output signal, if so, in order to prevent the optical fiber gyroscope 8 from generating a zero error at the position, the control module controls the driving unit 3 to act, the driving unit 3 drives the turntable mechanism to rotate, and drives the optical fiber gyroscope 8 to rotate by a predetermined angle to reach a non-error angle position; and then, controlling the driving unit 3 to act so that the turntable mechanism drives the optical fiber gyroscope 8 to rotate to a preset position, when the optical fiber gyroscope 8 rotates to the preset position, calculating an inclination angle result by the inclination angle calculation module according to an output signal of the optical fiber gyroscope 8, and calculating a second inclination angle result according to the inclination angle result and a preset angle.

In some modes, when judging that fiber optic gyroscope 8 is located error angle position within range, through the action of control drive unit 3, control fiber optic gyroscope 8 clockwise rotation 45 degrees in order to reach non-error angle position, then, under the condition that fiber optic gyroscope 8 is located non-error angle position, control fiber optic gyroscope 8 rotates to predetermined position, according to fiber optic gyroscope 8 in the output signal of predetermined position collection, utilize formula (1) calculation inclination result, later, subtract 45 degrees with the inclination result that obtains, obtain the second inclination result, as seeking north result, can eliminate zero point error, improve and seek north measurement accuracy.

As shown in the figure, in this embodiment, the north-seeking apparatus further includes a photoelectric encoder 6, and the data processing unit further includes:

and the position judgment module is used for judging whether the optical fiber gyroscope 8 reaches a preset position according to the acquired output signal of the photoelectric encoder 6.

In some embodiments, the position determining module is configured to determine a first rotation angle of the driving unit 3 according to the acquired rotation parameter of the optical encoder 6, determine a second rotation angle of the driving unit 3 according to the driving parameter of the driving unit 3 and a control parameter corresponding to controlling the driving unit 3 to move so that the optical fiber gyroscope 8 reaches a predetermined position, determine whether the first rotation angle and the second rotation angle are equal to each other, and if so, determine that the optical fiber gyroscope 8 reaches the predetermined position.

In some embodiments, the driving unit 3 is a stepping motor, an output shaft of the stepping motor rotates, the turntable mechanism drives the photoelectric encoder 6 and the optical fiber gyroscope 8 to rotate therewith, the control module determines the first rotation angle of the driving unit 3 according to the rotation parameter of the photoelectric encoder 6, and the calculation method is as follows:

wherein, theta_tFor the angle of rotation of the stepping motor during time t, n_tThe number of the code discs which are rotated by the photoelectric encoder in the time t is N, and the N is the total number of the code discs of the photoelectric encoder and can be determined according to the selected photoelectric encoder. Optionally, the total number of code discs of the selected photoelectric encoder is 2000.

In some embodiments, the second rotation angle of the driving unit 3 is determined according to the driving parameter of the driving unit 3 and a control parameter corresponding to controlling the driving unit 3 to act so as to enable the optical fiber gyroscope 8 to reach a predetermined position, and the calculation method is as follows:

wherein, theta_cFor controlling the fiber optic gyroscope 8 to reach the c-th preset rotation angle, u, corresponding to the predetermined position_cIn order to achieve the c-th preset rotation angle, the number of pulses required to be sent is determined, r is the reduction ratio of the speed reducer, and D is the subdivision of the stepping motor drive. Optionally, the reduction ratio of the selected speed reducer is 50, and the step motor drive is subdivided into 2000.

Calculating according to the formula (2) to obtain a first rotation angle theta_tThe second rotation is calculated according to the formula (3)Angle theta_cWhen theta is_t＝θ_cWhen it is determined that the optical fiber gyro 8 has reached the predetermined position. If theta₁When the optical fiber gyroscope 8 reaches the 1 st preset rotation angle corresponding to the first preset position, the rotation angle is equal to theta₁＝θ_tThen, it is judged that the optical fiber gyro 8 has reached the first predetermined position; if theta₂When the optical fiber gyroscope 8 reaches the 2 nd preset rotation angle corresponding to the second preset position, the angle theta is calculated₂＝θ_tThen, it is judged that the optical fiber gyro 8 has reached the second predetermined position; if theta₃When the optical fiber gyroscope 8 reaches the 3 rd preset rotation angle corresponding to the third preset position, the angle theta is equal to the preset rotation angle theta₃＝θ_tThen, it is judged that the optical fiber gyro 8 has reached the third predetermined position; if theta₄When the optical fiber gyroscope 8 reaches the 4 th preset rotation angle corresponding to the fourth preset position, the angle theta is determined₄＝θ_tAnd then, judging that the optical fiber gyroscope 8 reaches the fourth preset position, wherein the time t for the optical fiber gyroscope 8 to reach the four preset positions is different, and the number of code discs rotated by the photoelectric encoder 6 in the time t is different.

As shown in fig. 2A and fig. 5, in this embodiment, the north-seeking apparatus can not only measure the inclination angle and realize accurate north-seeking, but also measure the inclination angle of the apparatus relative to the horizontal direction. The north-seeking device further comprises a MEMS tilt sensor 15, and the data processing unit further comprises:

and the inclination angle calculation module is used for calculating an inclination angle result according to the output signal of the MEMS inclination angle sensor 15 when the acquired optical fiber gyroscope 8 is located at the preset position.

In some embodiments, the tilt angle calculation module calculates the tilt angle result by:

wherein β is the tilt angle of the MEMS tilt sensor 15 with respect to the horizontal direction (or the included angle between the north-seeking device and the horizontal direction), L is the total number of output signals of the MEMS tilt sensor 15 obtained when the fiber optic gyroscope 8 is located at a predetermined position, Y_jFor the output signal of the MEMS tilt sensor in the Y-axis direction, X, when the optical fiber gyroscope 8 is located at the j-th predetermined position_jThe output signal of the MEMS tilt sensor in the X-axis direction when the optical fiber gyroscope 8 is located at the j-th predetermined position.

Alternatively, based on the foregoing four-position north-seeking algorithm of the north-seeking apparatus, j is1, 2,3,4, L is 4, that is, when the apparatus is located at the first predetermined position, the second predetermined position, the third predetermined position, and the fourth predetermined position, the tilt angle result of the apparatus is calculated.

In this embodiment, when the optical fiber gyroscope 8 is located at a predetermined position, the inclination angle of the north seeker relative to the horizontal direction is calculated according to the acquired output signal of the MEMS inclination sensor 15, so that not only the function of the north seeker is expanded, but also the accuracy of the measured inclination angle is high.

In some modes, the X axis of the MEMS tilt sensor 15 coincides with the scale mark of the optical fiber gyroscope 8, the scale mark of the optical fiber gyroscope 8 is used for indicating the sensitive axis direction of the optical fiber gyroscope 8, and the first tilt result obtained by calculation according to the formula (1) is the included angle between the scale mark and the due north direction, and is also the initial position of the stepping motor. Optionally, the MEMS tilt sensor 15 is a tilt sensor having X-axis and Y-axis outputs, for example, a MEMS tilt sensor model ADIS16209 may be used.

As shown in fig. 1, 2A, 2B and 2C, in some embodiments, the north seeker includes a base plate 1, a first support plate 5, a turntable 7 and a second support plate 9, the base plate 1 is connected to the first support plate 5 through at least one support post 2, an output shaft of a driving unit 3 is connected to an input end of a speed reducer 4, the speed reducer 4 is fixed to one side of the first support plate 5, a photoelectric encoder 6 is fixed to the other side of the first support plate 5, a grating disc of the photoelectric encoder 6 is coaxially connected to an output shaft of the speed reducer 4, one side of the turntable 7 is connected to an output shaft end face of the speed reducer and can rotate with rotation of the speed reducer 4, the other side of the turntable 7 is connected to one side of the second support plate 9 through a fixing frame 12, a fiber optic gyroscope 8 is fixed to the fixing frame 12, a MEMS tilt sensor 15 is fixed to one side of the second support plate 9, one end, the signal end of the slip ring 13 is connected with the data input end of the data processing unit, the signal output ends of the optical fiber gyroscope 8 and the photoelectric encoder 6 are connected with the data input end of the data processing unit through the slip ring 13, the control signal end of the data processing unit is connected with the control end of the driving motor 3 through the slip ring 13, the signal output end of the electronic compass 14 is connected with the data input end of the data processing unit through a data line, the data processing unit is realized based on the circuit board 10, and the circuit board 10 is fixedly connected with the upper cover 11 through a connecting piece.

As shown in fig. 3, in this embodiment, the north seeker further includes an outer cylinder 16, the outer cylinder 16 is fixedly connected to the bottom plate 1 and the upper cover 11 in a sealing manner, optionally, the height of the north seeker is 326 mm, and the diameter of the upper cover 11 is 100 mm; the whole north-seeking device is compact in structure, reasonable in layout, small in size, particularly suitable for being used underground, and capable of providing accurate measurement inclination angle and inclination angle functions for various observation instruments installed underground.

As shown in fig. 5, in some embodiments, the data processing unit includes a main control chip, the signal output terminals of the electronic compass 14, the optical fiber gyroscope 8, and the optical fiber gyroscope 6 are respectively connected to the signal input terminal of the main control chip, the control signal output terminal of the main control chip is connected to the control terminal of the driving unit 3, the output shaft of the driving unit 3 is connected to the input terminal of the speed reducer 4, the output shaft of the speed reducer 4 is connected to the optical fiber gyroscope 6, the output shaft end surface of the speed reducer 4 is connected to the turntable 7, the main control chip controls the output shaft of the driving unit 3 to rotate, and the optical fiber gyroscope 8 on the photoelectric encoder 6, the turntable 7, and the turntable 7 can be driven to rotate after being decelerated.

The working process of the north-seeking device is that the main control chip rapidly judges whether the current position of the optical fiber gyroscope 8 is within an error angle position range according to the acquired azimuth output signal acquired by the electronic compass 14, if not, the main control chip controls the driving unit 3 to act so that the optical fiber gyroscope 8 reaches four preset positions, and when the optical fiber gyroscope 8 reaches the four preset positions according to the output signal of the photoelectric encoder 6, a first inclination angle result is calculated according to the acquired output signal of the optical fiber gyroscope 8 to realize north-seeking; if judge the current position of fiber gyroscope 8 within the error angular position scope, 3 actions of main control chip control drive unit, with 8 clockwise rotations 45 degrees of fiber gyroscope, so that fiber gyroscope 8 is located non-error angular position, then, 3 actions of main control chip control drive unit, make fiber gyroscope 8 reach four preset positions, according to photoelectric encoder 6's output signal, when judging fiber gyroscope 8 and reaching four preset positions, according to the output signal of fiber gyroscope 8 who obtains, calculate the inclination result, subtract 45 degrees with the inclination result again, obtain the second inclination result, realize seeking north.

Meanwhile, when the optical fiber gyroscope 8 reaches four preset positions, the main control chip calculates an inclination angle result according to the acquired output signal of the MEMS inclination angle sensor 15.

As shown in fig. 5, the data processing unit further includes a time service module, a data transmission interface, and a storage module, where the time service module is used to provide accurate time service for the north seeker; the storage module is used for storing the first inclination angle result or the second inclination angle result, the inclination angle result and corresponding time, and specifically, the measured first inclination angle result or the measured second inclination angle result and the measured inclination angle result can be stored according to time service and a time format of year, month, day, hour, minute and second; the main control chip calculates a first inclination angle result or a second inclination angle result, an inclination angle result and corresponding time and transmits the first inclination angle result or the second inclination angle result, the inclination angle result and the corresponding time to the terminal through the data transmission interface, and particularly, when the north-seeking device is applied to the underground, the data processing unit is connected with the ground equipment through the data transmission interface and the CAN bus, and CAN transmit the first inclination angle result or the second inclination angle result, the inclination angle result and the corresponding time of the measurement result data which are obtained through measurement to the ground equipment.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, is limited to these examples; within the spirit of the present disclosure, features from the above embodiments or from different embodiments may also be combined, steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present description as described above, which are not provided in detail for the sake of brevity.

In addition, well-known power/ground connections to Integrated Circuit (IC) chips and other components may or may not be shown in the provided figures, for simplicity of illustration and discussion, and so as not to obscure one or more embodiments of the disclosure. Furthermore, devices may be shown in block diagram form in order to avoid obscuring the understanding of one or more embodiments of the present description, and this also takes into account the fact that specifics with respect to implementation of such block diagram devices are highly dependent upon the platform within which the one or more embodiments of the present description are to be implemented (i.e., specifics should be well within purview of one skilled in the art). Where specific details (e.g., circuits) are set forth in order to describe example embodiments of the disclosure, it should be apparent to one skilled in the art that one or more embodiments of the disclosure can be practiced without, or with variation of, these specific details. Accordingly, the description is to be regarded as illustrative instead of restrictive.

While the present disclosure has been described in conjunction with specific embodiments thereof, many alternatives, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art in light of the foregoing description. For example, other memory architectures (e.g., dynamic ram (dram)) may use the discussed embodiments.

It is intended that the one or more embodiments of the present specification embrace all such alternatives, modifications and variations as fall within the broad scope of the appended claims. Therefore, any omissions, modifications, substitutions, improvements, and the like that may be made without departing from the spirit and principles of one or more embodiments of the present disclosure are intended to be included within the scope of the present disclosure.