Method and system for testing scale factor of atomic interference gyroscope

Abstract

The invention provides an atomic interference gyroscope scale factor test method and system, and the method comprises the steps: fixing an atomic interference gyroscope on a rotary table, starting the atomic interference gyroscope, and taking a Raman light DDS generator phase as a first output phase of the atomic interference gyroscope; starting the rotary table, controlling the rotary table to rotate forward and backward at a given angular speed, and recording a second output phase after waist locking phase compensation; after the test is finished, recording a third output phase of the atom interference gyroscope when the rotary table is static, and calculating an output average value of the atom interference gyroscope when the rotary table is static according to the first output phase and the third output phase; based on the second output phase and the average value, calculating the output of the atom gyroscope under different given angular velocities, and constructing a corresponding input and output model of the atom interference gyroscope; and solving the model through least square fitting to obtain a scale factor. According to the scheme, the environment vibration interference resistance is high, the test precision is high, the measurement speed is high, and the efficiency is high.

Description

Technical Field

[0001] The invention belongs to the field of quantum precision measurement, and in particular relates to a method and system for testing a scale factor of an atomic interferometer gyroscope. Background Art

[0002] As a new generation of inertial measurement instruments, atomic interferometer gyroscopes have great application prospects. The scale factor of an atomic interferometer gyroscope is the ratio of its output to its input. The scale factor nonlinearity and scale factor repeatability measure the maximum deviation of the gyroscope scale factor within the input angular rate range and the consistency between repeated tests of the gyroscope scale factor under the same conditions. These two indicators are the main performance indicators of the gyroscope. Only by accurately measuring the gyroscope scale factor can the performance of the atomic interferometer gyroscope be reasonably evaluated.

[0003] Atomic interferometer gyroscopes are seriously affected by environmental vibration and noise. Under phase-sweeping timing, the system has poor ability to distinguish interference fringes after being placed on the turntable, and cannot accurately calculate the rotation phase, which will lead to inaccurate measurement of the scale factor. The common solution is to calculate the rotation phase with the addition of table vibration compensation while scanning the phase, but this solution is relatively complicated, and the measurement accuracy depends on the effect of the addition of table vibration compensation, and the accuracy of the scale factor cannot be guaranteed.

[0004] At present, there are two common methods for testing gyro scale factors: one is to point the gyro reference axis to the sky, and obtain the rotation phase information based on the turntable at different rotation speeds to calculate the scale factor; the other is to make the gyro reference axis parallel to the horizontal plane, and after the gyro reference axis finds north, use the azimuth turntable to obtain the rotation phase information at different azimuth angles to calculate the scale factor. The former has a fast measurement speed, but the accuracy is not high due to the influence of vibration factors, while the latter takes a long time due to the need for accurate north finding and is inconvenient to operate. Summary of the invention

[0005] In view of this, an embodiment of the present invention provides a method and system for testing a scale factor of an atomic interferometer gyroscope, which are used to solve the problems of low accuracy and long operation time of current scale factor testing.

[0006] In a first aspect of an embodiment of the present invention, a method for testing a scale factor of an atomic interferometer gyroscope is provided, comprising: Fix the atomic interference gyroscope on the turntable so that the reference axis of the atomic interference gyroscope is vertically pointed upward to the sky, and power is supplied to the atomic interference gyroscope and the turntable; The atomic interferometer gyroscope is started, and the phase of the Raman light DDS generator is obtained when the turntable is stationary, and the phase of the Raman light DDS generator is used as the first output phase of the atomic interferometer gyroscope; Starting the turntable, controlling the turntable to rotate forward and reverse at a given angular velocity, respectively, and recording the second output phase of the atomic interferometer gyroscope after performing waist-locking phase compensation on the atomic interferometer gyroscope; The waist-locking phase compensation is the phase compensation required to adjust the left and right atomic groups of the gyroscope to work in the middle position of the interference fringes; After the test, the third output phase of the atomic interferometer gyroscope when the turntable is stationary is recorded, and the output average value of the atomic interferometer gyroscope when the turntable is stationary is calculated based on the first output phase and the third output phase; Based on the second output phase and the average output of the atomic interferometer gyroscope when the turntable is stationary, the output of the atomic interferometer gyroscope under different given angular velocities is calculated, and the corresponding input and output model of the atomic interferometer gyroscope is constructed; The test data of the atomic gyroscope output under different given angular velocities are obtained, and the input and output model of the atomic interferometer gyroscope is solved by least square fitting to obtain the atomic interferometer gyroscope scale factor.

[0007] In a second aspect of an embodiment of the present invention, a system for testing a scale factor of an atomic interferometer gyroscope is provided, comprising: The atomic interferometer gyroscope is used to obtain the phase of the Raman light DDS generator when the turntable is stationary as the first output phase after the gyroscope is started, perform waist-locking phase compensation according to computer instructions after the turntable is started, and obtain the second output phase, and after the test is completed, obtain the third output phase when the turntable is stationary, and send the first output phase, the second output phase and the third output phase to the computer; The waist-locking phase compensation is the phase compensation required to adjust the left and right atomic groups of the gyroscope to work in the middle position of the interference fringes; A turntable, used for forward and reverse rotation according to the angular velocity given by the computer; The atomic interference gyroscope is fixed on a turntable, the atomic interference gyroscope rotates with its reference axis pointing vertically upward to the sky, and the atomic interference gyroscope and the turntable are powered on; The computer is used for controlling the atomic interference gyroscope to perform waist-locking phase compensation, setting the angular velocity of the turntable, and receiving the first output phase, the second output phase, and the third output phase, calculating the output average value of the atomic interference gyroscope when the turntable is stationary according to the first output phase and the third output phase, calculating the output of the atomic gyroscope under different given angular velocities based on the second output phase and the output average value of the atomic interference gyroscope when the turntable is stationary, and constructing the corresponding input-output model of the atomic interference gyroscope, obtaining the test data of the atomic gyroscope output under different given angular velocities, solving the input-output model of the atomic interference gyroscope by least square fitting, and obtaining the scale factor of the atomic interference gyroscope.

[0008] In the embodiment of the present invention, the rotation phase offset is calculated by adopting the waist-locked phase compensation method, and it is used as the phase change value caused by the rotation, so as to solve the scale factor of the gyroscope input-output model. Therefore, not only is the ability to resist environmental vibration interference strong, the scale factor test has high accuracy, but also, compared with the traditional north-seeking azimuth measurement scale factor, the measurement speed is fast, the efficiency is high and the operation is convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0010] Figure 1 A schematic diagram of the principle of a method for testing the scale factor of an atomic interferometer gyroscope provided by an embodiment of the present invention; Figure 2 A schematic flow chart of a method for testing the scale factor of an atomic interferometer gyroscope provided by an embodiment of the present invention; Figure 3 A schematic structural diagram of an atomic interferometer gyroscope scale factor testing system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0011] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, 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 embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0012] It should be understood that the term "including" and other similar expressions in the specification or claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions, such as a process, method, system, or device including a series of steps or units is not limited to the listed steps or units. In addition, "first" and "second" are used to distinguish different objects, not to describe a specific order.

[0013] In one embodiment, the atomic interferometer gyroscope scale factor test principle is as follows Figure 1As shown, the test system includes an atomic interferometer gyroscope, a turntable, a computer, a control cable 1 and a control cable 2. The turntable and the computer are connected by a control cable 1. The turntable serves as a carrier of the atomic interferometer gyroscope to realize the rotation of the gyroscope under different speed conditions. The atomic interferometer gyroscope and the computer are connected by a control cable 2, which is fixed on the turntable surface to receive computer instructions and output rotation information. The computer is used to send instructions to control the rotation of the turntable, receive the rotation information of the atomic interferometer gyroscope, and send instructions to realize the atomic interferometer gyroscope waist lock phase compensation, so as to obtain the output phase information for scale factor calculation.

[0014] See also Figure 2 Another embodiment of the present invention provides a schematic flow chart of a method for testing a scale factor of an atomic interferometer gyroscope, including: S201, fixing the atomic interference gyroscope on a turntable so that the reference axis of the atomic interference gyroscope is vertically pointed upward to the sky, and energizing the atomic interference gyroscope and the turntable; The atomic interference gyroscope is a gyroscope based on the principle of atomic interference, and is generally used to measure angular velocity. It cools atoms to near absolute zero to form matter waves. When these atoms propagate in opposite directions in a circular optical path, the Sagnac effect caused by the rotation will cause the optical paths of the two matter waves to be different, resulting in a phase difference, and the angular velocity can be calculated based on the phase difference.

[0015] The turntable is a platform that is controlled by a computer and rotates in a forward or reverse direction at a set angular velocity. The atomic interference gyroscope is fixed to the turntable so that the atomic interference gyroscope can rotate with the turntable at a fixed angular velocity.

[0016] The atomic interferometer gyroscope's rotation reference axis points vertically upward to the sky, which means it points in the direction opposite to gravity, that is, the sky in the northeast celestial coordinate system (station center coordinate system).

[0017] S202, starting the atomic interferometer gyroscope, obtaining the phase of the Raman light DDS generator when the turntable is stationary, and using the phase of the Raman light DDS generator as the first output phase of the atomic interferometer gyroscope; The Raman optical DDS (Direct Digital Synthesis) generator is a Raman optical signal generator, which modulates the signal source signal and changes the Raman optical phase by controlling the radio frequency signal of the Raman optical signal.

[0018] S203, starting the turntable, controlling the turntable to rotate forward and reverse at a given angular velocity, and recording the second output phase of the atomic interferometer gyroscope after waist-locking phase compensation is performed on the atomic interferometer gyroscope; The waist-locking phase compensation is the phase compensation required to adjust the left and right atomic groups of the gyroscope to work in the middle position of the interference fringes; The atomic interferometer gyroscope is a three-pulse interferometer gyroscope, that is, a three-Raman pulse gyroscope.

[0019] It can be understood that the atomic interference signal of the atomic interferometer gyroscope satisfies the following formula: ; At small angles:

[0020]

[0021]

[0022] Combining the above two equations, the phase It can be expressed as:

[0023] For the two atoms on the left and right with opposite effective wave vectors, , A simple calculation can give the rotation phase : =

[0024] When the atomic interference gyro is placed on the turntable, the left and right atomic groups are adjusted to work at the waist of the interference fringes. When the turntable is stationary, the rotation phase of the solution is is a fixed value, which can be used as the output of the atomic interferometer gyroscope when it is stationary. When the speed rotates, will change, and the amount of change is Phase output of atomic interferometer gyroscope at rotation speed.

[0025] Optionally, the phase of the single Raman light DDS generator in the atomic group interference process is controlled by a PID algorithm, so that the left and right atomic groups of the atomic interference gyroscope work at the middle position of the interference fringes without changing.

[0026] The single Raman light DDS phase in the atomic group interference process is controlled by the PID algorithm to compensate for the phase change caused by the rotation of the turntable, so that the atomic groups on the left and right of the atomic interference gyroscope are calculated by the formula It remains unchanged. In this case, the change in DDS phase can be equivalent to the atomic interferometer gyro rotation phase caused by the rotation of the turntable. Finally, the atomic interferometer gyroscope scale factor can be obtained by calculating the DDS phase output by the atomic interferometer gyroscope.

[0027] S204, after the test is completed, the third output phase of the atomic interferometer gyroscope when the turntable is stationary is recorded, and the output average value of the atomic interferometer gyroscope when the turntable is stationary is calculated according to the first output phase and the third output phase; Among them, after the test, the output phase of the atomic interferometer gyroscope is recorded when the turntable is stationary. , i.e. the third output phase, combined with the Raman DDS phase recorded at the beginning of the test when the turntable was stationary , that is, the first output phase, according to formula (1), the average phase value of the atomic interferometer gyroscope output when the turntable is stationary is obtained: ; (1) In the formula, represents the average output of the atomic interferometer gyroscope when the turntable is stationary, represents the first output phase, Indicates the third output phase.

[0028] S205, calculating the output of the atomic gyroscope at different given angular velocities based on the second output phase and the average output of the atomic interferometer gyroscope when the turntable is stationary, and constructing a corresponding atomic interferometer gyroscope input and output model; Specifically, the output of the atomic gyroscope at different given angular velocities is calculated according to formula (2): - ; (2) In the formula, Indicates the nth given angular velocity The output of the atomic gyroscope is represents the second output phase of the atomic interferometer gyroscope under phase compensation, It represents the average output of the atomic interferometer gyroscope when the turntable is stationary; The input and output model of the constructed atomic interferometer gyroscope is expressed as: ; (3) Where K is the scale factor of the atomic gyroscope, represents the angular velocity of the turntable, Indicates the fitting zero position.

[0029] S206, obtaining test data of the atomic gyroscope output under different given angular velocities, solving the atomic interferometer gyroscope input and output model by least square fitting, and obtaining the atomic interferometer gyroscope scale factor.

[0030] Based on multiple sets of test data, the least squares method is used to fit the straight line and the scale factor K of the atomic interferometer gyroscope is calculated.

[0031] In this embodiment, the atomic interferometer gyroscope is subjected to a waist-locked phase compensation method to calculate the rotational phase offset, which is used as the phase change value of the atomic interferometer gyroscope caused by the rotation of the turntable. The atomic interferometer gyroscope scale factor is then calculated in combination with the test data. This method not only has strong resistance to environmental vibration interference and high accuracy, but also has fast and efficient scale factor measurement speed.

[0032] It should be understood that the serial numbers of the steps in the above embodiments do not imply a sequence of execution, and the execution sequence of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0033] Figure 3 A schematic diagram of the structure of an atomic interferometer gyroscope scale factor test system provided by an embodiment of the present invention, the system comprising: The atomic interferometer gyroscope 310 is used to obtain the phase of the Raman light DDS generator when the turntable is stationary as the first output phase after the gyroscope is started, perform waist-locking phase compensation according to computer instructions after the turntable is started, and obtain the second output phase, and obtain the third output phase when the turntable is stationary after the test, and send the first output phase, the second output phase and the third output phase to the computer 330; The waist-locking phase compensation is the phase compensation required to adjust the left and right atomic groups of the gyroscope to work in the middle position of the interference fringes; The turntable 320 is used to rotate forward and reverse according to the angular velocity given by the computer 330; The atomic interference gyroscope 310 is fixed on the turntable 320, the atomic interference gyroscope 310 rotates with the reference axis pointing vertically upward to the sky, and the atomic interference gyroscope 310 and the turntable 320 are powered on; The computer 330 is used to control the atomic interferometer gyroscope 310 to perform waist-locking phase compensation, set the angular velocity of the turntable 320, and receive the first output phase, the second output phase, and the third output phase. The output average value of the atomic interferometer gyroscope when the turntable is stationary is calculated according to the first output phase and the third output phase. The output of the atomic interferometer gyroscope under different given angular velocities is calculated based on the second output phase and the average output value of the atomic interferometer gyroscope when the turntable is stationary, and the corresponding input-output model of the atomic interferometer gyroscope is constructed to obtain the test data of the atomic gyroscope output under different given angular velocities. The input-output model of the atomic interferometer gyroscope is solved by least squares fitting to obtain the scale factor of the atomic interferometer gyroscope.

[0034] The atomic interferometer gyroscope 310 is a three-pulse interferometer gyroscope.

[0035] Specifically, the atomic interferometer gyroscope lock waist phase compensation includes: The phase of the single Raman light DDS generator in the process of atomic group interference is controlled by PID algorithm, so that the left and right atomic groups of the atomic interference gyroscope work in the middle position of the interference fringes without changing.

[0036] The average output value of the atomic interferometer gyroscope when the turntable is stationary is calculated according to formula (1): ; (1) In the formula, represents the average output of the atomic interferometer gyroscope when the turntable is stationary, represents the first output phase, Indicates the third output phase.

[0037] Among them, the output of the atomic gyroscope at different given angular velocities is calculated according to formula (2): - ; (2) In the formula, Indicates the nth given angular velocity The output of the atomic gyroscope is represents the second output phase of the atomic interferometer gyroscope under phase compensation, It represents the average output of the atomic interferometer gyroscope when the turntable is stationary; The input and output model of the constructed atomic interferometer gyroscope is expressed as: ; (3) Where K is the scale factor of the atomic gyroscope, represents the angular velocity of the turntable, Indicates the fitting zero position.

[0038] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and modules described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0039] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0040] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for testing the scale factor of an atomic interferometer gyroscope, characterized in that: include: Fix the atomic interference gyroscope on the turntable so that the reference axis of the atomic interference gyroscope is vertically pointed upward to the sky, and power is supplied to the atomic interference gyroscope and the turntable; The atomic interferometer gyroscope is started, and the phase of the Raman light DDS generator is obtained when the turntable is stationary, and the phase of the Raman light DDS generator is used as the first output phase of the atomic interferometer gyroscope; Starting the turntable, controlling the turntable to rotate forward and reverse at a given angular velocity, respectively, and recording the second output phase of the atomic interferometer gyroscope after performing waist-locking phase compensation on the atomic interferometer gyroscope; The waist-locking phase compensation is the phase compensation required to adjust the left and right atomic groups of the gyroscope to work in the middle position of the interference fringes; After the test, the third output phase of the atomic interferometer gyroscope when the turntable is stationary is recorded, and the output average value of the atomic interferometer gyroscope when the turntable is stationary is calculated based on the first output phase and the third output phase; Based on the second output phase and the average output of the atomic interferometer gyroscope when the turntable is stationary, the output of the atomic interferometer gyroscope under different given angular velocities is calculated, and the corresponding input and output model of the atomic interferometer gyroscope is constructed; The test data of the atomic gyroscope output under different given angular velocities are obtained, and the input and output model of the atomic interferometer gyroscope is solved by least square fitting to obtain the atomic interferometer gyroscope scale factor.

2. The method according to claim 1, characterized in that The atomic interferometer gyroscope is a three-pulse counter-throw type.

3. The method according to claim 1, characterized in that The control turntable rotates forward and reversely at a given angular velocity respectively, and recording the second output phase of the atomic interferometer gyroscope after the atomic interferometer gyroscope is subjected to waist-locking phase compensation comprises: The phase of the single Raman light DDS generator in the atomic interferometer gyroscope atomic group interference process is controlled by PID algorithm, so that the left and right atomic groups of the atomic interferometer gyroscope work in the middle position of the interference fringes without changing.

4. The method according to claim 1, characterized in that: The method of calculating the output average value of the atomic interferometer gyroscope when the turntable is stationary according to the first output phase and the third output phase comprises: According to formula (1), the average output of the atomic interferometer gyroscope when the turntable is stationary is calculated: ;（1） In the formula, represents the average output of the atomic interferometer gyroscope when the turntable is stationary, represents the first output phase, Indicates the third output phase.

5. The method according to claim 1, characterized in that The calculation of the atomic gyroscope output at different given angular velocities based on the second output phase and the average output of the atomic interferometer gyroscope when the turntable is stationary, and the construction of the corresponding atomic interferometer gyroscope input and output model comprises: According to formula (2), the output of the atomic gyroscope at different given angular velocities is calculated: - ；（2） In the formula, Indicates the nth given angular velocity The output of the atomic gyroscope is represents the second output phase of the atomic interferometer gyroscope under phase compensation, It represents the average output of the atomic interferometer gyroscope when the turntable is stationary; The input and output model of the constructed atomic interferometer gyroscope is expressed as: ；（3） Where K is the scale factor of the atomic gyroscope, represents the angular velocity of the turntable, Indicates the fitting zero position.

6. An atomic interferometer gyroscope scale factor test system, characterized in that: include: The atomic interferometer gyroscope is used to obtain the phase of the Raman light DDS generator when the turntable is stationary as the first output phase after the gyroscope is started, perform waist-locking phase compensation according to computer instructions after the turntable is started, and obtain the second output phase, and after the test is completed, obtain the third output phase when the turntable is stationary, and send the first output phase, the second output phase and the third output phase to the computer; The waist-locking phase compensation is the phase compensation required to adjust the left and right atomic groups of the gyroscope to work in the middle position of the interference fringes; A turntable, used for forward and reverse rotation according to the angular velocity given by the computer; The atomic interference gyroscope is fixed on a turntable, the atomic interference gyroscope rotates with its reference axis pointing vertically upward to the sky, and the atomic interference gyroscope and the turntable are powered on; The computer is used for controlling the atomic interference gyroscope to perform waist-locking phase compensation, setting the angular velocity of the turntable, and receiving the first output phase, the second output phase, and the third output phase, calculating the average output of the atomic interference gyroscope when the turntable is stationary according to the first output phase and the third output phase, calculating the output of the atomic gyroscope under different given angular velocities based on the second output phase and the average output of the atomic interference gyroscope when the turntable is stationary, and constructing a corresponding input-output model of the atomic interference gyroscope, obtaining test data of the atomic gyroscope output under different given angular velocities, solving the input-output model of the atomic interference gyroscope by least squares fitting, and obtaining the scale factor of the atomic interference gyroscope.

7. The system according to claim 6, characterized in that The atomic interferometer gyroscope is a three-pulse counter-throw type.

8. The system according to claim 6, characterized in that The atomic interferometer gyroscope waist-locking phase compensation comprises: The phase of the single Raman light DDS generator in the atomic interferometer gyroscope atomic group interference process is controlled by PID algorithm, so that the left and right atomic groups of the atomic interferometer gyroscope work in the middle position of the interference fringes without changing.

9. The system according to claim 6, characterized in that The method of calculating the output average value of the atomic interferometer gyroscope when the turntable is stationary according to the first output phase and the third output phase comprises: According to formula (1), the average output of the atomic interferometer gyroscope when the turntable is stationary is calculated: ;（1） In the formula, represents the average output of the atomic interferometer gyroscope when the turntable is stationary, represents the first output phase, Indicates the third output phase.

10. The system according to claim 6, characterized in that The calculation of the atomic gyroscope output at different given angular velocities based on the second output phase and the average output of the atomic interferometer gyroscope when the turntable is stationary, and the construction of the corresponding atomic interferometer gyroscope input and output model comprises: According to formula (2), the output of the atomic gyroscope at different given angular velocities is calculated: - ；（2） In the formula, Indicates the nth given angular velocity The output of the atomic gyroscope is represents the second output phase of the atomic interferometer gyroscope under phase compensation, It represents the average output of the atomic interferometer gyroscope when the turntable is stationary; The input and output model of the constructed atomic interferometer gyroscope is expressed as: ；（3） Where K is the scale factor of the atomic gyroscope, represents the angular velocity of the turntable, Indicates the fitting zero position.

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