CN109813296B - Angle measuring device and method for eliminating scale factor error of fiber-optic gyroscope - Google Patents
Angle measuring device and method for eliminating scale factor error of fiber-optic gyroscope Download PDFInfo
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- CN109813296B CN109813296B CN201910224761.8A CN201910224761A CN109813296B CN 109813296 B CN109813296 B CN 109813296B CN 201910224761 A CN201910224761 A CN 201910224761A CN 109813296 B CN109813296 B CN 109813296B
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Abstract
The invention discloses an angle measuring device and method for eliminating scale factor errors of a fiber-optic gyroscope. The angle measuring device comprises a box body base, a self-aligning bearing, a leveling platform, a supporting spring and an aligning shaft, wherein the self-aligning bearing is installed on the box body base, the upper end of the aligning shaft is fixed with the leveling platform, and the supporting spring is installed between the leveling platform and the box body base and used for supporting and isolating vibration; an inclination angle sensor is arranged on the leveling platform, and the optical fiber gyroscope is fixed on the leveling platform and is positioned right above the adjusting shaft; the leveling platform is provided with an inclination adjusting unit and a locking unit. The angle measurement method comprises the following steps of 1) pre-calibrating a scale factor of the fiber-optic gyroscope; 2) and (5) actual measurement. The invention can adjust the inclination state of the leveling platform according to the output of the inclination angle sensor to eliminate the influence of the inclination state on the scale factor, or compensate the angle measurement result according to the output of the inclination angle sensor, thereby eliminating the scale factor error caused by different inclination states of the installation plane on different occasions.
Description
Technical Field
The invention relates to an angle measuring device and method for eliminating scale factor errors of a fiber-optic gyroscope.
Background
Angle measurement is an important component of geometric measurement technology, and is increasingly widely applied to the fields of aerospace, semiconductor manufacturing, optical-mechanical-electrical integration and the like. Some current angle measurement methods, such as laser interference, moire fringe technology, and ring laser, have great limitations in terms of accuracy, sensitivity, and dynamic range in practical applications. The optical fiber gyroscope (FOG) is an angular velocity sensor based on the Sagnac effect, and has the advantages of high starting speed, wide dynamic range, simple structure, low price, high precision and sensitivity and the like, so the optical fiber gyroscope is widely applied to the field of angle measurement. At present, the scale factor of the fiber-optic gyroscope is an important factor influencing the angle measurement accuracy, and the scale factor is a quantity changing along with the installation state of the fiber-optic gyroscope, so that before the fiber-optic gyroscope is installed for testing each time, the scale factor needs to be calibrated again to avoid the influence caused by installation errors. When the angle generating device such as a rotary table is lacked in practical application occasions and calibration cannot be carried out, inconvenience is brought to the use of the optical fiber gyroscope, and even the accuracy of measurement cannot be ensured.
Disclosure of Invention
In order to overcome the defects, the invention provides an angle measuring device and method for eliminating the scale factor error of a fiber-optic gyroscope.
An angle measuring device for eliminating scale factor errors of a fiber optic gyroscope comprises a box body base, a self-aligning bearing, a leveling platform, a supporting spring and an aligning shaft, wherein the self-aligning bearing is installed on the box body base, the upper end of the aligning shaft is fixed with the leveling platform, and the supporting spring is installed between the leveling platform and the box body base and used for supporting and isolating shock;
an inclination angle sensor is arranged on the leveling platform, and the optical fiber gyroscope is fixed on the leveling platform and is positioned right above the adjusting shaft;
the leveling platform is provided with an inclination adjusting unit and a locking unit.
The inclination adjusting unit comprises a thread pair, a thread pair metal cap and a thread pair metal rod, wherein the thread pair is fixed on the leveling platform, the thread pair metal cap is sleeved on the thread pair metal rod, the thread pair metal rod connects the box body base, the leveling platform and the thread pair together through a through hole in the leveling platform, and the thread pair metal cap drives the thread pair metal rod to rotate so as to adjust the inclination state of the leveling platform.
The locking unit comprises a locking screw and a locking screw metal cap, the locking screw metal cap is sleeved on the locking screw, the locking screw is connected with the thread pair, and when the inclination state of the leveling platform is adjusted to a proper state, the locking screw is driven by rotating the locking screw metal cap to lock the inclination state of the leveling platform.
An angle measuring method using the angle measuring device,
1) pre-calibrating a scale factor of the fiber-optic gyroscope;
2) and (5) actual measurement.
And 1) pre-calibrating the scale factor of the fiber-optic gyroscope, and calibrating when the leveling platform is in a horizontal state or a non-horizontal state.
The invention has the beneficial effects that:
the invention realizes the measurement of the angle by using the information of the angular velocity of the sensitive outer part of the optical fiber gyroscope. Aiming at the characteristic that the scale factors of the fiber optic gyroscope are influenced by the installation plane and the installation state, the adjustable leveling platform is designed, the fiber optic gyroscope and the inclination angle sensor are fixedly installed on the adjustable leveling platform, compared with a common installation mode, the influence of installation errors caused by the difference between the installation planes in different application occasions is eliminated, and the inclination state of the installed leveling platform is adjustable, so that the influence of the inclination state of the leveling platform on the scale factors can be eliminated by adjusting the inclination state of the leveling platform according to the output of the inclination angle sensor in actual use, or the angle measurement result is compensated according to the output of the inclination angle sensor, so that the scale factor errors caused by the different inclination states of the installation planes in different occasions are eliminated, and the accuracy of the angle measurement result is ensured.
Drawings
FIG. 1 is a schematic structural diagram of an angle measuring device for eliminating scale factor errors of a fiber-optic gyroscope according to the present invention;
wherein: the device comprises a box body base 1, a self-aligning bearing 2, a leveling platform 3, an optical fiber gyroscope 4, an inclination angle sensor 5, a thread pair 6, a thread pair metal cap 7, a thread pair metal rod 8, a locking screw 9, a locking screw metal cap 10, a supporting spring 11 and a self-aligning shaft 12.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
As shown in fig. 1, an angle measuring device for eliminating scale factor errors of a fiber optic gyroscope comprises a box base 1, a self-aligning bearing 2, a leveling platform 3, a supporting spring 11 and a self-aligning shaft 12, wherein the self-aligning bearing 2 is installed on the box base 1, and the upper end of the self-aligning shaft 12 is fixed with the leveling platform 3, so that when the inclination state of the leveling platform 3 changes, the inclination direction of the self-aligning shaft 12 correspondingly changes along with the inclination state of the leveling platform 3 under the action of the self-aligning bearing 2, and a plurality of supporting springs 11 are installed between the leveling platform 3 and the box base 1 and used for supporting and isolating shock.
The leveling platform 3 is provided with the tilt angle sensor 5, the optical fiber gyroscope 4 is fixed on the leveling platform 3 and is positioned right above the aligning shaft 12, and the tilt state of the leveling platform 3 is determined through the output of the tilt angle sensor 5, so that the leveling platform 3 is the installation platform of the optical fiber gyroscope 4 no matter what the actual application occasion is, the consistency of the installation platform under different application conditions is ensured, and the error of a scale factor caused by the difference of the installation platform can be effectively avoided.
The leveling platform 3 is provided with an inclination adjusting unit and a locking unit.
The inclination adjusting unit comprises thread pairs 6 (totally 4 and distributed at four corners of the leveling platform 3), thread pair metal caps 7 (totally 4 and distributed at four corners of the leveling platform 3), thread pair metal rods 8 (totally 4 and distributed at four corners of the leveling platform 3), wherein the thread pairs 6 are fixed on the leveling platform 3, the thread pair metal caps 7 are sleeved on the thread pair metal rods 8, the thread pair metal rods 8 connect the box body base 1, the leveling platform 3 and the thread pairs 6 together through holes in the leveling platform 3, and the thread pair metal caps 7 drive the thread pair metal rods 8 to rotate, so that the inclination state of the leveling platform 3 is adjusted, and the design can ensure the consistency of the inclination state of the optical fiber gyroscope mounting plane (namely the leveling platform 3) by adjusting the leveling platform 3 on different occasions.
The locking unit comprises locking screws 9 (totally 4, distributed at four corners of the leveling platform 3) and locking screw metal caps 10 (totally 4, distributed at four corners of the leveling platform 3). The locking screw metal cap 10 is sleeved on the locking screw 9, the locking screw 9 is connected with the thread pair 6, and when the inclination state of the leveling platform 3 is adjusted to a proper state, the locking screw 9 is driven by rotating the locking screw metal cap 10 to realize the locking of the inclination state of the leveling platform 3.
Examples
When the device is used, two using methods are generally adopted, specifically as follows:
the method comprises the following steps:
1. pre-calibrating a scale factor of the fiber-optic gyroscope; firstly, the device is arranged on an angle/angular velocity generating device (such as a high-precision rotary table and the like) to accurately calibrate the scale factor of the fiber-optic gyroscope 4, before calibration, a locking screw 9 is loosened to enable the leveling platform 3 to be in an adjustable state, a screw pair metal cap 7 which is sleeved on a screw pair metal rod 8 in a rotating mode drives the screw pair metal rod 8 to rotate, so that the inclination state of the leveling platform 3 is adjusted, the output of the inclination angle sensor 5 is continuously collected in real time in the adjusting process until the output of the inclination angle sensor 5 is zero, and the leveling platform 3 is in the horizontal state at the moment. And then screwing the locking screw 9, locking the current state of the leveling platform 3, starting to calibrate the scale factor of the fiber-optic gyroscope, and recording the scale factor value obtained by calibration as K.
2. Actual measurement in different situations; when the device is used for measuring an actual angle, the device is installed on the plane of an actually measured carrier, and because the difference exists between the plane of the carrier and the plane of the angle/angular velocity generating device when the scale factor is calibrated in advance or because of the deviation caused by the installation process and the like, the output of the inclination angle sensor 5 may not be 0 at the moment, namely the leveling platform 3 is not in the horizontal position, and if K is used as the scale factor before being directly used at the moment, an error is generated. Therefore, the locking screw 9 is loosened to enable the leveling platform 3 to be in an adjustable state, the thread pair metal cap 7 sleeved on the thread pair metal rod 8 in a rotating mode drives the thread pair metal rod 8 to rotate, and therefore the inclination state of the leveling platform 3 is adjusted until the output of the inclination angle sensor 5 is zero, and the fact that the leveling platform 3 at the moment is indicatedHas been in the horizontal state again. The locking screw 9 is then rotated to lock the current state of the levelling bench 3, at which point the previous scale factor K is used again for the actual measurement. It is assumed that during the measurement, the single-point output angle increment value of the fiber-optic gyroscope 4 (the output value refers to the value of the fiber-optic gyroscope after subtracting the static output) is marked as FiAnd the total number of sampling points is N, the angle measurement result theta is expressed as:
the second method comprises the following steps:
1. pre-calibrating a scale factor of the fiber-optic gyroscope; firstly, the device of the invention is arranged on an angle/angular velocity generating device (such as a high-precision turntable and the like) to accurately calibrate the scale factor of the optical fiber gyroscope 4, but the method does not need to adjust the leveling platform 3 to enable the output of the tilt sensor 5 to be zero, only needs to record the output of the corresponding tilt sensor 5 when calibrating the scale factor of the optical fiber gyroscope, and records the output as (alpha, beta), wherein alpha represents the tilt angle of the output of the tilt sensor 5 along the X-axis direction, beta represents the tilt angle of the output of the tilt sensor 5 along the Y-axis direction, and records the scale factor calibrated in the state as (alpha, beta)K α，β（）. At this time, the angle between the normal direction of the leveling platform 3 and the normal direction of the horizontal plane
Can be expressed as:
2. actual measurement in different situations; when the device of the invention is used for actual angle measurement, the device of the invention is arranged on the plane of an actual measured carrier, and before the measurement is started, the output of the inclination angle sensor 5 at the moment is recorded and recorded as (alpha)1，β1). At this time, the angle between the normal direction of the leveling platform 3 and the normal direction of the horizontal plane
Can be expressed as:
it is assumed that during the measurement, the single-point output angle increment value of the fiber-optic gyroscope 4 (the output value refers to the value of the fiber-optic gyroscope after subtracting the static output) is marked as FiAnd the total number of sampling points is N, the angle measurement result theta is expressed as:
in the device, the consistency of the installation plane of the fiber-optic gyroscope is realized by the design of the leveling platform 3 when aiming at different measured carriers, so that the error caused by the difference of the installation plane is avoided, the adjustment of the inclination state of the installation plane of the fiber-optic gyroscope 4 and the compensation of the angle measurement result are realized by combining the output of the leveling platform 3 and the output of the inclination angle sensor 5 when the device is applied to different measured carriers, the universality of the calibrated scale factor on different measured carriers is realized, and the problem that the calibrated scale factor cannot be directly used when the calibrated scale factor cannot be calibrated again due to the limitation of the use condition in actual use, so that the error exists can be effectively avoided.
Claims (3)
1. A method for measuring an angle without leveling by using an angle measuring device is characterized in that,
1) pre-calibrating a scale factor of the fiber-optic gyroscope when the leveling platform is in any state:
firstly, an angle measuring device is arranged on an angle/angular velocity generating device to accurately calibrate the scale factor of the fiber-optic gyroscope (4), the output of the tilt sensor (5) is zero without adjusting a leveling platform (3), and the output of the corresponding tilt sensor (5) when the scale factor of the fiber-optic gyroscope is calibrated is recorded and is recorded as (alpha, beta)) Wherein alpha represents the inclination angle of the output of the inclination angle sensor (5) along the X-axis direction, beta represents the inclination angle of the output of the inclination angle sensor (5) along the Y-axis direction, and the calibrated scale factor in the state is recorded asK α，β（）(ii) a At the moment, the included angle between the normal direction of the leveling platform (3) and the normal direction of the horizontal plane
Expressed as:
2) and (3) actual measurement:
when actual angle measurement is performed, an angle measuring device is mounted on the plane of an actual measured carrier, and before measurement is started, the output of the inclination angle sensor (5) at that time is recorded and recorded as (alpha)1，β1) At the moment, the included angle between the normal direction of the leveling platform (3) and the normal direction of the horizontal plane
Expressed as:
assuming that the single-point output angle increment value of the fiber-optic gyroscope (4) is recorded as F in the measurement processiAnd the total number of sampling points is N, the angle measurement result theta is expressed as:
the angle measuring device comprises a box body base (1), a self-aligning bearing (2), a leveling platform (3), a supporting spring (11) and a self-aligning shaft (12), wherein the self-aligning bearing (2) is installed on the box body base (1), the upper end of the leveling shaft (12) is fixed with the leveling platform (3), and the supporting spring (11) is installed between the leveling platform (3) and the box body base (1) and used for supporting and isolating vibration;
an inclination angle sensor (5) is arranged on the leveling platform (3), and the optical fiber gyroscope (4) is fixed on the leveling platform (3) and is positioned right above the adjusting shaft (12);
the leveling platform (3) is provided with an inclination adjusting unit and a locking unit.
2. The method according to claim 1, characterized in that the inclination adjusting unit comprises a screw pair (6), a screw pair metal cap (7) and a screw pair metal rod (8), wherein the screw pair (6) is fixed on the leveling platform (3), the screw pair metal cap (7) is sleeved on the screw pair metal rod (8), the screw pair metal rod (8) connects the box base (1), the leveling platform (3) and the screw pair (6) together through a through hole on the leveling platform (3), and the screw pair metal cap (7) drives the screw pair metal rod (8) to rotate, so as to adjust the inclination state of the leveling platform (3).
3. The method according to claim 2, wherein the locking unit comprises a locking screw (9) and a locking screw metal cap (10), the locking screw metal cap (10) is sleeved on the locking screw (9), the locking screw (9) is connected with the thread pair (6), and when the inclination state of the leveling platform (3) is adjusted to a proper state, the locking screw (9) is driven to lock the inclination state of the leveling platform (3) by rotating the locking screw metal cap (10).
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| CN111220141B (en) * | 2020-02-25 | 2021-06-25 | 北京航空航天大学 | Shaft aligning method for direct coupling of polarization maintaining optical fiber ring terminal and integrated optical chip |
| CN112697168B (en) * | 2020-11-27 | 2022-05-20 | 浙江大学 | Measuring device and method for simultaneously measuring scale factor and misalignment angle of fiber-optic gyroscope |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6108086A (en) * | 1999-03-04 | 2000-08-22 | Litton Systems, Inc. | System and method of stabilizing the scale factor shift in fiber optic gyroscopes using a spectral monitor array |
| US6209383B1 (en) * | 1997-05-21 | 2001-04-03 | Daimler-Benz Aerospace Ag | Arrangement for calibrating several gyro systems |
| CN1821721A (en) * | 2006-03-27 | 2006-08-23 | 北京航空航天大学 | Precise decoupling detecting method for gyroscope scale factor and input shaft default angle |
| CN201138270Y (en) * | 2007-12-27 | 2008-10-22 | 中国航天时代电子公司 | Mass center measuring apparatus suitable for optical fiber gyroscope apparatus |
| CN102135420A (en) * | 2010-12-10 | 2011-07-27 | 浙江大学 | Method for improving angular displacement measurement accuracy of optical fiber gyroscope |
| CN104034350A (en) * | 2014-05-21 | 2014-09-10 | 浙江大学 | Rapid testing method for optical fiber gyroscope scale factor parameter |
| CN204007639U (en) * | 2014-08-15 | 2014-12-10 | 湖北航天技术研究院总体设计所 | A kind of optical fibre gyro ring body structurc |
| CN104792339A (en) * | 2015-04-24 | 2015-07-22 | 无锡慧联信息科技有限公司 | Calibration method of fiber optic gyroscope (FOG) inclinometer |
| CN204944513U (en) * | 2015-08-10 | 2016-01-06 | 湖北三江航天红峰控制有限公司 | A kind of testing and debugging device of gyro reference axle |
| CN108168536A (en) * | 2017-12-13 | 2018-06-15 | 陕西宝成航空仪表有限责任公司 | The accurate measurement method of optical fibre gyro zero bias |
| CN207887213U (en) * | 2017-12-29 | 2018-09-21 | 绍兴市柯桥区欧祥机械有限公司 | A kind of experiment porch of step-less adjustment height |
-
2019
- 2019-03-24 CN CN201910224761.8A patent/CN109813296B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6209383B1 (en) * | 1997-05-21 | 2001-04-03 | Daimler-Benz Aerospace Ag | Arrangement for calibrating several gyro systems |
| US6108086A (en) * | 1999-03-04 | 2000-08-22 | Litton Systems, Inc. | System and method of stabilizing the scale factor shift in fiber optic gyroscopes using a spectral monitor array |
| CN1821721A (en) * | 2006-03-27 | 2006-08-23 | 北京航空航天大学 | Precise decoupling detecting method for gyroscope scale factor and input shaft default angle |
| CN201138270Y (en) * | 2007-12-27 | 2008-10-22 | 中国航天时代电子公司 | Mass center measuring apparatus suitable for optical fiber gyroscope apparatus |
| CN102135420A (en) * | 2010-12-10 | 2011-07-27 | 浙江大学 | Method for improving angular displacement measurement accuracy of optical fiber gyroscope |
| CN104034350A (en) * | 2014-05-21 | 2014-09-10 | 浙江大学 | Rapid testing method for optical fiber gyroscope scale factor parameter |
| CN204007639U (en) * | 2014-08-15 | 2014-12-10 | 湖北航天技术研究院总体设计所 | A kind of optical fibre gyro ring body structurc |
| CN104792339A (en) * | 2015-04-24 | 2015-07-22 | 无锡慧联信息科技有限公司 | Calibration method of fiber optic gyroscope (FOG) inclinometer |
| CN204944513U (en) * | 2015-08-10 | 2016-01-06 | 湖北三江航天红峰控制有限公司 | A kind of testing and debugging device of gyro reference axle |
| CN108168536A (en) * | 2017-12-13 | 2018-06-15 | 陕西宝成航空仪表有限责任公司 | The accurate measurement method of optical fibre gyro zero bias |
| CN207887213U (en) * | 2017-12-29 | 2018-09-21 | 绍兴市柯桥区欧祥机械有限公司 | A kind of experiment porch of step-less adjustment height |
Non-Patent Citations (3)
| Title |
|---|
| 《A New Open-Loop Fiber Optic Gyro Error Compensation》;Yanshun Zhang;《Sensors》;20150227;第4899-4912页 * |
| 光纤陀螺稳定平台调平系统设计;赖小明等;《计算机测量与控制》;20070331(第03期);第363-365页 * |
| 光纤陀螺组件快速高精度标定方法;李松等;《辽宁工程技术大学学报(自然科学版)》;20180228(第01期);第169-173页 * |
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