A compound inertial system attitude simulation test method

Abstract

A kind of compound inertial system attitude simulation test method, compound inertial system obtains launch system initial attitude angle by initial alignment mode;In dynamic loading process, the inertial data of compound inertial system is collected, and the angle signal of attitude simulation platform excitation is synchronously acquired;The attitude of compound inertial system is converted from launch system to local horizontal coordinate system by navigation solution method, while the angle signal of attitude simulation test platform is converted to the attitude angle of local horizontal coordinate system, and relevant operation is carried out, to obtain the dynamic performance parameter of compound inertial system.

Description

Technical Field

[0001] This invention relates to a method for attitude simulation testing of a composite inertial system, belonging to the field of inertial navigation testing technology. Background Technology

[0002] A fiber optic gyroscope inertial system is a composite inertial system that uses a platform servo loop to stabilize the platform coordinate system and simultaneously achieves an analytical platform coordinate system through attitude integration. During inertial navigation operation, it can switch between platform mode, strapdown mode, and rotation modulation mode, among others.

[0003] To achieve optimal navigation accuracy throughout the entire flight process, a composite inertial system needs to implement the optimal operating mode arrangement under different flight profiles. Therefore, ground attitude simulation tests are required to verify the navigation accuracy of different operating mode arrangements and switching combinations under typical flight profiles.

[0004] Existing attitude simulation testing methods are only applicable to simple inertial platform operation modes or simple strapdown inertial navigation operation modes. For inertial systems employing multiple operation modes in a single flight profile, a unified attitude simulation testing method has not yet been developed, making it impossible to accurately assess inertial navigation accuracy by combining flight profile data. This patent designs an attitude simulation testing method suitable for composite inertial systems, filling a technological gap in existing testing methods. Summary of the Invention

[0005] The technical problem solved by this invention is that current technologies cannot perform attitude simulation and accuracy evaluation of inertial systems with multiple working modes in a single flight profile. Therefore, this invention proposes a composite inertial system attitude simulation test method.

[0006] The present invention solves the above-mentioned technical problem through the following technical solution: A method for attitude simulation testing of a composite inertial system, comprising: The composite inertial system used for attitude simulation and strapdown attitude calculation is fixed to the attitude simulation test bench with screws, and the initial attitude angle of the launch system is obtained through initial alignment. After the experiment begins, the inertial data of the composite inertial system and the excitation angle signal of the attitude simulation test bench are acquired through the synchronous signal generator until the experiment ends. Based on the initial attitude angles and inertial data of the launch system of the composite inertial system, and the attitude transformation matrix from the launch system to the horizontal coordinate system, the attitude angle data and attitude matrix of the composite inertial system in the horizontal coordinate system are obtained. Based on the real-time geocentric and geofixed position information of the composite inertial system, calculate the latitude, longitude, and altitude information of the composite inertial system. The dynamic characteristics of the composite inertial system are evaluated using attitude angle data, attitude matrix, and latitude, longitude, and altitude information in the horizontal coordinate system.

[0007] The attitude simulation test bench is used to simulate attitude data during flight simulation. During the flight simulation, any or a combination of platform, strapdown, and rotary modulation modes are used to optimize and obtain the state target with the minimum position and attitude discrete error of the inertial system.

[0008] The attitude angle data of the composite inertial system in the horizontal coordinate system are as follows:

[0009] In the formula, the pitch angle is yaw angle is The roll angle is , , , , , These are matrix elements.

[0010] After each transformation matrix element is determined based on the attitude transformation matrix, the element values ​​are confirmed using the attitude transformation matrix from the launch system to the horizontal coordinate system. These values ​​are then used to calculate the attitude angle data of the composite inertial system in the horizontal coordinate system. The attitude transformation matrix from the launch system to the horizontal coordinate system is as follows:

[0011] The method for determining the matrix elements in the attitude transformation matrix from the launch system to the horizontal coordinate system is as follows: The attitude matrix of the composite inertial system in the launch frame, the attitude matrix of the composite inertial system from the launch frame to the Earth-centered Earth-fixed frame, the attitude matrix of the composite inertial system from the Earth-centered Earth-fixed frame to the local horizontal coordinate system, and the attitude matrix from the right-front-upper load system to the front-upper-right load system are used to determine the attitude matrix. After determining the attitude transformation matrix from the launch system to the horizontal coordinate system, it is used to convert the matrix elements in the attitude transformation matrix.

[0012] Attitude transformation matrix from launch system to horizontal coordinate system The expression is:

[0013] In the formula, the attitude matrix of the composite inertial system in the launching frame is: The attitude matrix of the composite inertial system from the launch frame to the Earth-centered solid frame is: The attitude matrix of the composite inertial system from the Earth-centered Earth-fixed frame to the local horizontal coordinate system is: The attitude matrix from the right front-upload system to the front-upright load system is: .

[0014] The attitude matrix of the combined inertial system in the launch frame The expression is:

[0015] Attitude matrix of a composite inertial system from the launch frame to the Earth-centered solid frame The expression is:

[0016] Wherein: Initial longitude: Geographical latitude: Heading angle: .

[0017] Attitude matrix of a composite inertial system from the Earth-centered, Earth-fixed frame to the local horizontal coordinate system The expression is:

[0018] In the formula, the latitude of the carrier is Longitude is The height is .

[0019] The attitude matrix from the right-front-upper carrier coordinate system to the front-upper-right carrier coordinate system The expression is:

[0020] The direction cosine matrix from the right-front-upper carrier coordinate system to the front-upper-right carrier coordinate system is used to represent the rotational relationship between the two coordinate systems. The rotational relationship is as follows: .

[0021] The method for calculating the latitude, longitude, and altitude information of the composite inertial system based on its real-time geocentric and Earth-fixed frame position information is as follows: Based on the location of the composite inertial system in the Earth's core and solid system Determine the position of the matrix element And it is calculated by combining the inertial data of the composite inertial system.

[0022] The composite inertial system is located in the Earth's core and solid system. The calculation method is as follows:

[0023] In the formula, Indicates the initial value of the launch point location of the Earth-centered Earth-solid system. The composite inertial system at the launch system position With the position of the inertial system Same, make To complete the calculation of the location of the Earth's core and solid system.

[0024] in, , , The coordinates of the composite inertial system in the starting inertial frame can be derived from the initial longitude: Geographical latitude: and initial height Sure.

[0025] The latitude and longitude height information of the composite inertial system The calculation method is as follows:

[0026] In the formula, the radius of curvature of the zonal loop is... The Earth's semi-major axis is a, the Earth's semi-minor axis is b, the eccentricity is e, and the second eccentricity is... The Earth's rotational angular velocity is .

[0027] The advantages of this invention compared to the prior art are: (1) The present invention provides a composite inertial system attitude simulation test method, which obtains the initial attitude angle of the composite inertial system by adopting the initial alignment method. During the dynamic loading process of the attitude simulation test bench, the inertial data such as gyroscope and accelerometer in the composite inertial system and the frame angle signal of the attitude simulation test bench are collected synchronously. The accurate attitude of the inertial system platform relative to the local horizontal coordinate system is obtained by adopting the navigation calculation and attitude conversion method. The information conversion between the coordinate systems is realized by the corresponding algorithm calculation. (2) The present invention provides a composite inertial system attitude simulation test method, which realizes attitude simulation of inertial system and obtains attitude of inertial system through strapdown solution method; (3) The present invention can simulate attitude data during flight by using an attitude simulation test bench; during the simulated flight, the inertial system optimizes the state target with the minimum position and attitude discrete error by adopting platform, strapdown and rotation modulation modes, and solves the problem of difficulty in quickly evaluating the attitude simulation characteristics of composite inertial systems, improves the accuracy and reliability of quickly evaluating inertial systems, and provides a technical basis for the inertial navigation combination of new inertial systems and the improvement of navigation performance. Attached Figure Description

[0028] Figure 1 A flowchart of the coordinate transformation method provided by the present invention; Figure 2A schematic diagram of the attitude simulation test system for the composite inertial system under different working modes provided by the present invention; Figure 3 A schematic diagram of the test platform mode for the attitude simulation characteristics of the composite inertial system provided by the present invention; Figure 4 A schematic diagram of the strapdown mode for testing the attitude simulation characteristics of a composite inertial system provided by this invention; Figure 5 A schematic diagram of the rotation modulation mode for testing the attitude simulation characteristics of a composite inertial system provided by this invention. Detailed Implementation

[0029] A method for attitude simulation testing of a composite inertial system is disclosed. The composite inertial system obtains the initial attitude angle of the launch system through initial alignment. During dynamic loading, the inertial data of the composite inertial system is collected, and the excitation angle signal of the attitude simulation platform is acquired simultaneously. The attitude of the composite inertial system is transformed from the launch system to the local horizontal coordinate system through navigation calculation. At the same time, the angle signal of the attitude simulation platform is transformed into the attitude angle of the local horizontal coordinate system, and relevant calculations are performed to obtain the dynamic performance parameters of the composite inertial system.

[0030] A method for attitude simulation testing of a composite inertial system, comprising the following steps: The composite inertial system is fixed to the attitude simulation test bench with screws, and the initial attitude angle of the launch system is obtained through initial alignment. After the experiment begins, the inertial data of the composite inertial system and the excitation angle signal of the attitude simulation test bench are acquired through the synchronous signal generator until the experiment ends. Based on the initial attitude angles and inertial data of the launch system of the composite inertial system, and the attitude transformation matrix from the launch system to the horizontal coordinate system, the attitude angle data and attitude matrix of the composite inertial system in the horizontal coordinate system are obtained. Based on the real-time geocentric and geofixed position information of the composite inertial system, calculate the latitude, longitude, and altitude information of the composite inertial system. The dynamic characteristics of the composite inertial system are evaluated using attitude angle data, attitude matrix, and latitude, longitude, and altitude information in the horizontal coordinate system.

[0031] The attitude angle data of the composite inertial system in the horizontal coordinate system are as follows:

[0032] In the formula, the pitch angle is yaw angle is The roll angle is , , , , , These are matrix elements.

[0033] After each transformation matrix element is determined based on the attitude transformation matrix, the element values ​​are confirmed using the attitude transformation matrix from the launch system to the horizontal coordinate system. These values ​​are then used to calculate the attitude angle data of the composite inertial system in the horizontal coordinate system. The attitude transformation matrix from the launch system to the horizontal coordinate system is as follows: .

[0034] The method for determining the matrix elements in the attitude transformation matrix from the launch system to the horizontal coordinate system is as follows: The attitude matrix of the composite inertial system in the launch frame, the attitude matrix of the composite inertial system from the launch frame to the Earth-centered Earth-fixed frame, the attitude matrix of the composite inertial system from the Earth-centered Earth-fixed frame to the local horizontal coordinate system, and the attitude matrix from the right-front-upper load system to the front-upper-right load system are used to determine the attitude matrix. After determining the attitude transformation matrix from the launch system to the horizontal coordinate system, it is used to convert the matrix elements in the attitude transformation matrix.

[0035] Attitude transformation matrix from launch system to horizontal coordinate system The expression is:

[0036] In the formula, the attitude matrix of the composite inertial system in the launching frame is: The attitude matrix of the composite inertial system from the launch frame to the Earth-centered solid frame is: The attitude matrix of the composite inertial system from the Earth-centered Earth-fixed frame to the local horizontal coordinate system is: The attitude matrix from the right front-upload system to the front-upright load system is: .

[0037] Attitude matrix of the combined inertial system in the launch frame The expression is:

[0038] Attitude matrix of a composite inertial system from the launch frame to the Earth-centered solid frame The expression is:

[0039] Wherein: Initial longitude: Geographical latitude: Heading angle: .

[0040] Attitude matrix of a composite inertial system from the Earth-centered, Earth-fixed frame to the local horizontal coordinate system The expression is:

[0041] In the formula, the latitude of the carrier is Longitude is The height is .

[0042] Attitude matrix from right front-upload system to front-upright load system The expression is:

[0043] The direction cosine matrix (representing the rotation relationship between the two coordinate systems) of rotating from the "right-front-up" coordinate system to the "front-up-right" coordinate system is as follows: .

[0044] The method for calculating the latitude, longitude, and altitude information of the composite inertial system based on its real-time geocentric and Earth-fixed frame position information is as follows: Based on the location of the composite inertial system in the Earth's core and solid system Determine the position of the matrix element And it is calculated by combining the inertial data of the composite inertial system.

[0045] Composite inertial system at the Earth's core and Earth-solid system position The calculation method is as follows:

[0046] In the formula, Indicates the initial value of the launch point location of the Earth-centered Earth-solid system. The composite inertial system at the launch system position With the position of the inertial system Same, make To complete the calculation of the location of the Earth's core and solid system.

[0047] in, , , The coordinates of the composite inertial system in the starting inertial frame can be derived from the initial longitude: Geographical latitude: and initial height Sure.

[0048] Latitude and longitude information of the combined inertial system The calculation method is as follows:

[0049] In the formula, the radius of curvature of the zonal loop is... The Earth's semi-major axis is a, the Earth's semi-minor axis is b, the eccentricity is e, and the second eccentricity is... The Earth's rotational angular velocity is .

[0050] The following description, in conjunction with the accompanying drawings and preferred embodiments, provides further details: In the current embodiment, such as Figure 2 As shown, the composite inertial system is fixed to the position and attitude simulation test bench by screws, and the initial attitude angle of the launching system is obtained by the initial alignment method. During the dynamic simulation test, the inertial data of the composite inertial system and the excitation angle signal of the attitude simulation test bench are acquired simultaneously.

[0051] like Figure 1 As shown, the specific process of attitude simulation test includes: (1) The composite inertial system is fixed to the attitude simulation test bench by screws, and the initial attitude angle of the launch system is obtained by the initial alignment method; (2) During the test, the attitude simulation test bench is dynamically loaded. At the beginning of the test, the inertial data of the composite inertial system and the excitation angle signal of the attitude simulation test bench are synchronously acquired through the synchronous signal generator. At the end of the experiment, the acquisition of inertial data and attitude simulation test bench excitation angle signals of the composite inertial system was synchronously terminated by the synchronous signal generator. (3) Based on the initial attitude angles and inertial data of the composite inertial system, the transformation matrix from the launch system to the local horizontal coordinate system (Northeast Celestial Geographic System) is as follows: Obtain the yaw angle in the local horizontal coordinate system Pitch angle and roll angle :

[0052] Among them, pitch angle: Yaw angle: Roll angle: .

[0053] The attitude matrix of the carrier in the local horizontal coordinate system (Northeast China coordinate system) is as follows:

[0054] in, The attitude matrix from the right front-upload system to the front-upright load system: .

[0055] The attitude matrix of the carrier in the launch system (pitch angle: Yaw angle: Roll angle: ):

[0056] Here is the attitude matrix of the carrier from the launch system to the Earth-centered Earth-fixed system:

[0057] The attitude matrix from the Earth-centered Earth-fixed system to the local horizontal coordinate system (Northeast Celestial-Geographical System):

[0058] Among them, the latitude of the carrier: ,longitude: ,high: .

[0059] Initial longitude: Geographical latitude: Heading angle: .

[0060] Location of the Earth's core and solid system , is represented as: ,in: Indicates the initial value of the launch point location of the Earth-centered Earth-solid system. Position of the launch system With the position of the inertial system Equal, that is .

[0061] latitude and longitude of the carrier :

[0062] in: Earth's semi-major axis a, Earth's semi-minor axis b, eccentricity e, Earth's rotational angular velocity .

[0063] The attitude angle sequence of the attitude simulation test bench and the attitude angle of the composite inertial system are generated based on coordinate transformation. The attitude simulation process of the composite inertial system is obtained through the constructed attitude simulation system, and the attitude is obtained by strapdown calculation.

[0064] like Figure 3 The diagram shown is a schematic of a test platform mode for attitude simulation characteristics of a composite inertial system. Figure 4 The diagram shown is a schematic of the attitude simulation characteristic test of a composite inertial system in strapdown mode. Figure 5 As shown, this is a schematic diagram of the attitude simulation characteristic test of a composite inertial system - rotation modulation mode; the attitude simulation test bench can simulate attitude data during flight; and during the simulated flight, it uses platform, strapdown and rotation modulation modes to optimize and obtain the state target with the minimum position and attitude discrete error of the inertial system.

[0065] This embodiment provides an effective method for rapidly obtaining attitude data during simulated flight and evaluating the attitude simulation and test characteristics of composite inertial systems by enabling free transformation between multiple coordinate systems and performing related calculations during coordinate system transformations in inertial navigation. It allows for optimization to obtain the state target with the minimum position and attitude discrepancies during inertial navigation system flight by switching between platform mode, strapdown mode, and rotation modulation mode of the composite inertial system. This method can be applied to inertial systems and offers high accuracy and flexibility.

[0066] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

[0067] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A method for attitude simulation testing of a composite inertial system, characterized in that... include: The composite inertial system used for attitude simulation and strapdown attitude calculation is fixed to the attitude simulation test bench with screws, and the initial attitude angle of the launch system is obtained through initial alignment. After the experiment begins, the inertial data of the composite inertial system and the excitation angle signal of the attitude simulation test bench are acquired through the synchronous signal generator until the experiment ends. Based on the initial attitude angles and inertial data of the launch system of the composite inertial system, and the attitude transformation matrix from the launch system to the horizontal coordinate system, the attitude angle data and attitude matrix of the composite inertial system in the horizontal coordinate system are obtained. Based on the real-time geocentric and geofixed position information of the composite inertial system, calculate the latitude, longitude, and altitude information of the composite inertial system. The dynamic characteristics of the composite inertial system are evaluated using attitude angle data, attitude matrix, and latitude, longitude, and altitude information in the horizontal coordinate system.

2. The method for attitude simulation testing of a composite inertial system according to claim 1, characterized in that: The attitude simulation test bench is used to simulate attitude data during flight simulation. During the flight simulation, any or a combination of platform, strapdown, and rotary modulation modes are used to optimize and obtain the state target with the minimum position and attitude discrete error of the inertial system.

3. The method for attitude simulation testing of a composite inertial system according to claim 1, characterized in that: The attitude angle data of the composite inertial system in the horizontal coordinate system are as follows: In the formula, the pitch angle is yaw angle is The roll angle is , , , , , These are matrix elements.

4. The method for attitude simulation testing of a composite inertial system according to claim 3, characterized in that: After each transformation matrix element is determined based on the attitude transformation matrix, the element values ​​are confirmed using the attitude transformation matrix from the launch system to the horizontal coordinate system. These values ​​are then used to calculate the attitude angle data of the composite inertial system in the horizontal coordinate system. The attitude transformation matrix from the launch system to the horizontal coordinate system is as follows: 。 5. The method for attitude simulation testing of a composite inertial system according to claim 4, characterized in that: The method for determining the matrix elements in the attitude transformation matrix from the launch system to the horizontal coordinate system is as follows: The attitude matrix of the composite inertial system in the launch frame, the attitude matrix of the composite inertial system from the launch frame to the Earth-centered Earth-fixed frame, the attitude matrix of the composite inertial system from the Earth-centered Earth-fixed frame to the local horizontal coordinate system, and the attitude matrix from the right-front-upper load system to the front-upper-right load system are used to determine the attitude matrix. After determining the attitude transformation matrix from the launch system to the horizontal coordinate system, it is used to convert the matrix elements in the attitude transformation matrix.

6. The method for attitude simulation testing of a composite inertial system according to claim 5, characterized in that: Attitude transformation matrix from launch system to horizontal coordinate system The expression is: In the formula, the attitude matrix of the composite inertial system in the launching frame is: The attitude matrix of the composite inertial system from the launch frame to the Earth-centered solid frame is: The attitude matrix of the composite inertial system from the Earth-centered Earth-fixed frame to the local horizontal coordinate system is: The attitude matrix from the right front-upload system to the front-upright load system is: .

7. The method for attitude simulation testing of a composite inertial system according to claim 6, characterized in that: The attitude matrix of the combined inertial system in the launch frame The expression is: Attitude matrix of a composite inertial system from the launch frame to the Earth-centered solid frame The expression is: Wherein: Initial longitude: Geographical latitude: Heading angle: ; Attitude matrix of a composite inertial system from the Earth-centered, Earth-fixed frame to the local horizontal coordinate system The expression is: In the formula, the latitude of the carrier is Longitude is The height is .

8. The method for attitude simulation testing of a composite inertial system according to claim 6, characterized in that: The attitude matrix from the right-front-upper carrier coordinate system to the front-upper-right carrier coordinate system The expression is: The direction cosine matrix from the right-front-upper carrier coordinate system to the front-upper-right carrier coordinate system is used to represent the rotational relationship between the two coordinate systems. The rotational relationship is as follows: .

9. The method for attitude simulation testing of a composite inertial system according to claim 6, characterized in that: The method for calculating the latitude, longitude, and altitude information of the composite inertial system based on its real-time geocentric and Earth-fixed frame position information is as follows: Based on the location of the composite inertial system in the Earth's core and solid system Determine the position of the matrix element And it is calculated by combining the inertial data of the composite inertial system.

10. The method for attitude simulation testing of a composite inertial system according to claim 9, characterized in that: The composite inertial system is located in the Earth's core and solid system. The calculation method is as follows: In the formula, Indicates the initial value of the launch point location of the Earth-centered Earth-solid system. The composite inertial system at the launch system position With the position of the inertial system Same, make To complete the calculation of the location of the Earth's core and solid system; in, , , The coordinates of the composite inertial system in the starting inertial frame can be derived from the initial longitude: Geographical latitude: and initial height Sure.

11. The method for attitude simulation testing of a composite inertial system according to claim 10, characterized in that: The latitude and longitude height information of the composite inertial system The calculation method is as follows: In the formula, the radius of curvature of the zonal loop is... The Earth's semi-major axis is a, the Earth's semi-minor axis is b, the eccentricity is e, and the second eccentricity is... The Earth's rotational angular velocity is .

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