CN103674066B - A kind of method of testing of resolution of fiber-optic gyroscope - Google Patents

Abstract

A test method for the resolution of the fiber optic gyroscope is provided. First, adjust the rate turntable, then install the fiber optic gyroscope, and finally start the test. On the basis of the existing rate turntable, the present invention effectively eliminates the influence of the horizontal component of the earth's rotation on the resolution of the fiber optic gyroscope by improving the test method, thereby using the low-precision rate turntable to accurately test the resolution of the high-precision fiber optic gyroscope .

Description

A test method for fiber optic gyroscope resolution

technical field

The invention belongs to the technical field of inertial device testing and angular rate sensor calibration testing, and in particular relates to a testing method for the resolution of an optical fiber gyroscope.

Background technique

Fiber optic gyroscope is an angular rate sensor, which is used to measure the angular rate of motion of the carrier in inertial space, and is widely used in various fields such as aviation, aerospace, weapons and so on. With the improvement of fiber optic gyroscope development technology, the accuracy of fiber optic gyroscope is getting higher and higher. The resolution of the fiber optic gyroscope determines the accuracy of application systems such as navigation and north-seeking, and can also reflect the overall noise level of the fiber optic gyroscope. The rate turntable is the main instrument for testing the fiber optic gyroscope. The angular rate resolution of the existing rate turntable is lower than that of the fiber optic gyroscope. Therefore, how to accurately measure the resolution of the fiber optic gyroscope is of great significance to the development and production of the fiber optic gyroscope.

Contents of the invention

The technical problem solved by the present invention is to provide a test method for the resolution of the fiber optic gyroscope. On the basis of the existing rate turntable, by improving the test method, the influence of the horizontal component of the earth's rotation on the resolution of the test fiber optic gyroscope can be effectively eliminated , so as to accurately test the resolution of high-precision fiber optic gyro with a low-precision rate turntable.

The technical solution adopted in the present invention: a method for testing the resolution of an optical fiber gyroscope, comprising the following steps:

1) Adjust the rate turntable: tilt the tiltable rate turntable to the south, and the inclination angle formed with the horizon is equal to the geographical latitude angle of the test site. At this time, the axis of the turntable is perpendicular to the polar axis of the earth, eliminating the horizontal component of the earth's rotation on the fiber optic gyroscope test Impact;

2) Install the fiber optic gyroscope: fix the fiber optic gyroscope on the rate turntable through the hexahedral fixture, and make the axis of the turntable of the rate turntable and the input axis of the fiber optic gyroscope form an angle of 89.5°, and make the earth's polar axis perpendicular to the rate turntable The plane formed by the axial direction of the turntable and the input axis of the fiber optic gyroscope, at this time, the input angular rate of the fiber optic gyroscope and the angular rate of the rate turntable have a cosine relationship;

3) Start the test: use the computer to precisely control the angular rate of the rate turntable, and increase the minimum angular rate increment that the optical fiber gyroscope can be sensitive to on the basis of the specified input angular rate of the optical fiber gyroscope. The output increment generated by the angular rate increment is at least It should be equal to 50% of the expected output increment according to the scale factor, and the resolution of the fiber optic gyroscope can be obtained by multiple measurements.

In the above step 2), the angular rate resolution of the rate turntable is 1×10 ^-4 °/s, and the minimum angular rate of the fiber optic gyroscope tested by this method is 8.7×10 ^-7 °/s;

In step 3) above,

① First test the scaling factor K of the fiber optic gyroscope;

② Use the computer to accurately control the angular rate of the rate turntable in real time through the turntable controller, and collect the output of the fiber optic gyroscope. The rate turntable is fixed at an angular rate Ω _o , and the output of the fiber optic gyro is Y. When the input angular rate of the rate turntable is Ω _o After stabilization, the relationship between the input and output of the fiber optic gyroscope is: Y=KΩ _o cos89.5°

③ Add a small angular rate increment ΔΩ=0.1°/s on the basis of the angular rate of the rate turntable 1 is Ω _o , the corresponding expected value of the output increment of the fiber optic gyroscope is ΔY _o , collect the output value of the fiber optic gyroscope, and repeat the test Several times, take the average value ΔY, if satisfy Then the angular rate increment ΔΩ _o corresponding to this value is valid, and the angular rate increment ΔΩ ₁ is recorded;

④Take the angle increment ΔΩ _n =n ^-1 ΔΩ°/sn=2, 3, 4... in turn, repeat step ③ until the formula $\frac{\mathrm{\ΔY}}{{\mathrm{\ΔY}}_o}\&Greater\; Equal;50\%$ invalid;

⑤ Take the smallest angular rate increment among all angular rate increments ΔΩ _n n=1, 2, 3... as ΔΩ, then the positive resolution of the fiber optic gyroscope is θ ₊ =ΔΩcos89.5°;

⑥According to the same method, control the speed turntable 1 to run in the opposite direction, repeat steps ②, ③, ④, ⑤, and test the inversion resolution of the fiber optic gyroscope θ _- = ΔΩcos89.5°;

⑦ Take the absolute value of the measured positive and negative resolutions, and record the maximum value as θ, which is the resolution of the fiber optic gyroscope.

Compared with the prior art, the present invention is simple and easy to implement, meets the testing requirements of the fiber optic gyroscope, is convenient to install, is easy to implement, eliminates the influence of the earth's rotation on the fiber optic gyroscope test, and can accurately test the resolution of the fiber optic gyroscope.

Description of drawings

Fig. 1 is a schematic diagram of the test system of the present invention;

Fig. 2 is the schematic diagram of fiber optic gyroscope of the present invention;

Fig. 3 is a relationship diagram among the polar axis of the earth, the axis of the turntable and the axis of the fiber optic gyroscope.

detailed description

An embodiment of the present invention is described below in conjunction with accompanying drawings 1-3.

A method for testing the resolution of a fiber optic gyroscope, comprising the steps of:

1. Adjust the rate turntable: tilt the tiltable rate turntable 1 to the south, and the inclination angle formed with the horizon is equal to the geographic latitude angle of the test site. At this time, the axis 4 of the turntable is perpendicular to the polar axis of the earth, eliminating the impact of the horizontal component of the earth's rotation on the optical fiber Impact of the Gyro 5 test;

2. Install the fiber optic gyroscope: fix the fiber optic gyroscope 5 on the rate turntable 1 through the hexahedral fixture 3, and make the angle relationship between the turntable axis 4 of the rate turntable 1 and the input axis of the fiber optic gyroscope 5 be 89.5°, and make the earth The polar axis is perpendicular to the plane formed by the turntable axis 4 of the rate turntable 1 and the input axis of the fiber optic gyroscope 5. At this time, the input angular rate of the fiber optic gyroscope has a cosine relationship with the angular rate of the turntable, and the angular rate resolution of the rate turntable is 1× 10 ^-4 °/s, the minimum angular rate tested by this method is 8.7×10 ^-7 °/s, which is more than 100 times higher than the angular rate resolution of the turntable, and the precise test resolution is 2.7×10 ^{- 5} °/s fiber optic gyroscope;

3. Start the test: use the computer 7 to accurately control the angular rate of the rate turntable 1, increase the minimum angular rate increment that the optical fiber gyroscope 5 can be sensitive to on the basis of the input angular rate specified by the optical fiber gyroscope 5, and the angular rate generated by the angular rate increment The output increment should be at least equal to 50% of the expected output increment according to the scale factor, and the resolution of the fiber optic gyroscope 5 can be obtained through multiple measurements. Specifically include the following steps:

①Test the scaling factor K of the fiber optic gyroscope first, and get K=4.7×10 ⁷ bit/°;

② Use the computer 7 to accurately control the angular rate of the rate turntable 1 in real time through the turntable controller 6, and collect the output of the fiber optic gyroscope 5. The relationship between the input and output of the fiber optic gyroscope 5 is: Y=KΩ _o cos89.5°. The rate turntable 1 fixes an angular rate Ω ₀ =100°/s. When the input angular rate Ω _o of the rate turntable 1 is stable, the actual output value of the fiber optic gyro 5 is Y=4.08×10 ⁷ bit/s. The expected output value of the fiber optic gyroscope 5 is: Y=KΩ _o cos89.5°=4.1×10 ⁷ bit/s.

③ Add a small angular rate increment ΔΩ=0.1°/s on the basis of the angular rate of the rate turntable 1 is Ω _o , and the corresponding expected value of the output increment of the fiber optic gyroscope 5 is ΔY _o =4.1×10 ⁴ bit/s, Collect the output value of the fiber optic gyroscope 5, repeat the test several times, and take the average value ΔY=3.98×10 ⁴ bit/s, satisfying Then the angular rate increment ΔΩ _o corresponding to this value is valid, and record the angular rate increment ΔΩ ₁ =0.1°/s;

④ Take the angular increment ΔΩ _n = n ^-1 ΔΩ°/s (n=2, 3, 4...) in turn, repeat step ③ until the formula $\frac{\mathrm{\ΔY}}{{\mathrm{\ΔY}}_o}\&Greater\; Equal;50\%$ invalid;

When n=2, ΔY _o =2.05×10 ⁴ bit/s, ΔY=2.00×10 ⁴ bit/s, then is established, record the angular increment ΔΩ ₂ =0.05°/s;

When n=3, ΔY _o =1.37×10 ⁴ bit/s, ΔY=1.34×10 ⁴ bit/s, then is established, record the angular increment ΔΩ ₃ =0.03°/s;

When n=4, ΔY _o =1.04×10 ⁴ bit/s, ΔY=1.0×10 ⁴ bit/s, then is established, record the angular increment ΔΩ ₄ =0.025°/s;

………………………………………

When n=32, ΔY _o =1.28×10 ³ bit/s, ΔY=0.67×10 ³ bit/s, then established, record the angular increment ΔΩ ₃₂ =0.0031°/s;

When n=33, ΔY _o =1.24×10 ³ bit/s, ΔY=0.6×10 ³ bit/s, then invalid.

⑤ Take the smallest angular rate increment among all angular rate increments ΔΩ _n (n=1, 2, 3...) as ΔΩ=ΔΩ ₃₂ =0.0031°/s, then the positive resolution of the fiber optic gyroscope 5 is θ ₊ = ΔΩcos89.5°=2.7×10 ^-5 °/s=0.01°/h;

⑥According to the same method, control the speed turntable 1 to run in the opposite direction, repeat steps ②, ③, ④, ⑤, and test the inversion resolution of the fiber optic gyro 5 θ _- =ΔΩcos89.5°=—2.61×10 ^-5 °/s =—0.09°/h;

⑦ Take the measured positive resolution θ ₊ =0.01°/h and inverse resolution θ _- =—0.09°/h, take the absolute value, and record the maximum value as θ=0.01°/h, which is the 5 resolution of the fiber optic gyroscope Rate.

The foregoing embodiments are only preferred embodiments of the present invention, and are not intended to limit the scope of the present invention, so all equivalent changes made with the contents of the claims of the present invention should be included within the scope of the claims of the present invention .

Claims (2)

1. a method of testing for resolution of fiber-optic gyroscope, is characterized in that comprising the steps:

1) regulations speed turntable: by tiltable rate table (1) south dip, with inclining that horizon formsOblique angle equals the geographic latitude angle of test site, and now turntable shaft is vertical with earth pole axis to (4), eliminatesThe impact of earth rotation horizontal component on optical fibre gyro (5) test;

2) installing optical fibres gyro: optical fibre gyro (5) is fixed on to speed by hexahedron frock clamp (3)Rate turntable (1) is upper, and defeated to (4) and optical fibre gyro (5) of the turntable shaft that makes rate table (1)Enter and between axle, become 89.5 ° of angular relationships, and make earth pole axis perpendicular to the turntable shaft of rate table (1) to(4) plane forming with the power shaft of optical fibre gyro (5), the now input angle speed of optical fibre gyro (5)Rate becomes cosine relation with the angular speed of rate table (1);

3) start test: with the accurately angular speed of speed control turntable (1) of computer (7), at optical fiberIn the input angle rate basis of gyro (5) regulation, increase the minimum angular speed that optical fibre gyro (5) can be responsiveIncrement, the output increment being produced by this angular speed increment at least should equal by the desired output of scale factor50% of increment, repeatedly measures and obtains the resolution ratio of optical fibre gyro (5);

Above-mentioned steps 3) in,

1. the constant multiplier K of first measuring fiber gyro;

2. use computer (7) by turntable controller (6) speed control turntable (1) accurately in real timeAngular speed, and gather the output quantity of optical fibre gyro (5), rate table (1) is fixed an angular speed Ω_o，Optical fibre gyro (5) is output as Y, as the input angle speed Ω of rate table (1)_oAfter stable, optical fiberPass between the input of gyro (5) and output is: Y=K Ω_ocos89.5°

3. be Ω at rate table (1) angular speed_oBasis on increase little angular speed increment Delta Ω=0.1°/s, the desired value of corresponding optical fibre gyro (5) output increment is Δ Y_o, collection optical fibre gyro (5)Output valve, retest several times, get its mean value Δ Y, if meetThe angular speed increment Delta Ω of this value correspondence_oEffectively, record this angular speed increment Delta Ω₁；

4. get successively angle increment Δ Ω_n＝n^-1Δ Ω °/s (n=2,3,4 ...), repeating step 3., until formulaBe false;

5. get all angular speed increment Delta Ω_n(n=1,2,3 ...) in minimum angular speed increment be Δ Ω,The positive resolution ratio of optical fibre gyro (5) is θ₊＝ΔΩcos89.5°；

6. by identical method, speed control turntable (1) is running in the other direction, repeating step 2., 3.,4., 5., test to obtain optical fibre gyro (5) reversion resolution ratio θ_-＝ΔΩcos89.5°；

7. the positive and negative resolution ratio recording is taken absolute value, its maximum is designated as θ, is optical fibre gyro (5)Resolution ratio.

2. the method for testing of resolution of fiber-optic gyroscope according to claim 1, is characterized in that: onState step 2) in, the angular speed resolution ratio of rate table (1) is 1 × 10^-4°/s, survey in this wayThe minimum angular speed of the optical fibre gyro (5) of examination is 8.7 × 10^-7°/s。