A dynamic lever arm compensation method for optoelectronic pod inertial navigation

Abstract

The present invention relates to a dynamic lever arm compensation method for an optoelectronic pod inertial navigation system, comprising: obtaining a lever arm length 1 between a GPS signal receiving center and an optoelectronic pod platform rotation center, and obtaining a lever arm length 2 between an optoelectronic pod platform rotation center and an inertial element calculation center; obtaining a conversion matrix 1 and a conversion matrix 2 according to measurement data of platform rotation; obtaining a conversion matrix 3 according to measurement data of an inertial sensitive element; calculating an effective lever arm according to a lever arm compensation model, and realizing dynamic lever arm compensation for an optoelectronic pod inertial navigation system according to the calculated effective lever arm, thereby improving the effective use accuracy of the optoelectronic pod during operation.

Description

Technical Field

[0001] The invention relates to the technical field of inertial detection, and in particular to a dynamic lever arm compensation method for an optoelectronic pod inertial navigation. Background Art

[0002] Airborne optoelectronic pods are a type of dynamic platform measurement and control device that is hung on the outside of an aerial vehicle. They use optoelectronic detection systems to search, capture, and track targets. They are usually installed on armed reconnaissance helicopters and unmanned reconnaissance aircraft, and are widely used in enemy reconnaissance, target tracking, optoelectronic guided weapon simulation, power line inspection, maritime anti-smuggling, and environmental monitoring.

[0003] Since the rotation center of the three-axis platform of the optoelectronic pod does not coincide with the calculation center of the inertial element, the lever arm effect will cause the lever arm error in the pod solution process. In actual use, the lever arm between the GPS signal receiving center and the platform rotation center is directly used for the solution during its working process, ignoring the lever arm error caused by the misalignment of the platform rotation center and the calculation center of the inertial element. Summary of the invention

[0004] Aiming at the problem of lever arm error caused by lever arm effect in the use of current optoelectronic pod, the present invention provides a dynamic lever arm compensation method for inertial navigation of optoelectronic pod, which improves the use accuracy.

[0005] To achieve the above object, the present invention provides a dynamic lever arm compensation method for an optoelectronic pod inertial navigation system, comprising:

[0006] Obtain the arm length 1 between the GPS signal receiving center and the optoelectronic pod platform rotation center, and obtain the arm length 2 between the optoelectronic pod platform rotation center and the inertial sensor element calculation center;

[0007] According to the measurement data of the rotation of the optoelectronic pod platform, the conversion matrix from the carrier coordinate system to the inertial sensor coordinate system is obtained. And the transformation matrix from the inertial sensor coordinate system to the carrier coordinate system

[0008] According to the measurement data of the inertial sensor, the transformation matrix from the inertial sensor coordinate system to the carrier coordinate system is obtained.

[0009] The effective lever arm is calculated according to the lever arm compensation model as the lever arm of the GPS signal receiving center and the inertial sensitive element calculation center for navigation solution.

[0010] Furthermore, we get the transformation matrix And the transformation matrix 2 include:

[0011] The optoelectronic pod platform rotates around ZYX in sequence by angles α, β, and φ. The conversion matrix for:

[0012]

[0013] The transformation matrix for:

[0014]

[0015] Furthermore, the transformation matrix 3 from the inertial sensor coordinate system to the navigation coordinate system is obtained, including: obtaining the inertial group output attitude angles θ, ψ, γ

[0016] The transformation matrix three for:

[0017]

[0018] Furthermore, the effective lever arm is calculated according to the lever arm compensation model, and the lever arm compensation model is:

[0019]

[0020] in is the effective lever arm, is the length of the lever arm, is the length of the lever arm, is the transformation matrix 1, is the transformation matrix 2, is the transformation matrix three.

[0021] The above technical solution of the present invention has the following beneficial technical effects:

[0022] The method provided by the present invention measures the length of the lever arm between the rotation center and the calculation center of the inertial element, obtains a new lever arm for solving the problem during the operation of the optoelectronic pod through coordinate conversion compensation, thereby realizing dynamic lever arm compensation for the inertial navigation of the optoelectronic pod and improving the effective use accuracy during the operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the airborne optoelectronic pod;

[0024] Figure 2 Flowchart of pitch angle error compensation measured by accelerometer. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0026] like Figure 1 As shown, the optoelectronic pod inertial navigation includes a GPS signal receiving module 1, an optoelectronic pod suspension bracket 2, an inertial sensitive element 3, and an optoelectronic pod three-axis stable platform 4. The optoelectronic pod suspension bracket 2 is located on one side of the optoelectronic pod three-axis stable platform 4 and extends outward, the GPS signal receiving module 1 is located on the upper part of the optoelectronic pod suspension bracket 2, and the inertial sensitive element 3 is located on the upper part of the optoelectronic pod three-axis stable platform 4.

[0027] O b It is the GPS signal receiving center; O1 is the rotation center of the three-axis platform; O s It is the inertial sensitive element solution center. In practical applications, the lever arm is generally ignored. This will cause a certain position error in the navigation solution process. The effective lever arm obtained by the present invention after compensation Participating in the navigation solution can eliminate the problem of ignoring the lever arm. The position error caused.

[0028] The present invention provides a method for dynamic arm compensation of an optoelectronic pod inertial navigation system, comprising obtaining a GPS signal receiving center O b The length of the arm of the optoelectronic pod platform rotation center O1 is Obtain the optoelectronic pod platform rotation center O1 and the inertial element calculation center O s The arm length of

[0029] According to the measurement data of platform rotation, the transformation matrix from the carrier coordinate system to the inertial sensor coordinate system can be obtained: And the transformation matrix from the inertial sensor coordinate system to the carrier coordinate system According to the measurement data of the inertial sensor, the conversion matrix from the inertial sensor coordinate system to the navigation coordinate system can be obtained:

[0030] The platform rotates around ZYX in sequence by angles α, β, and φ. The transformation matrix is for:

[0031]

[0032] The transformation matrix for:

[0033]

[0034] The measurement data of the inertial sensor include: the inertial group output attitude angles θ, ψ, γ

[0035] The transformation matrix three for:

[0036]

[0037] The effective lever arm is calculated according to the lever arm compensation model, and the lever arm compensation model is:

[0038]

[0039] in is the effective lever arm, is the length of the lever arm, is the length of the lever arm, is the transformation matrix 1, is the transformation matrix 2, is the transformation matrix three.

[0040] The equivalent lever arm is obtained by the compensation method Participate in navigation position solution, effectively eliminating the problem of ignoring the lever arm Caused by position error.

[0041] In summary, the present invention relates to a dynamic lever arm compensation method for an optoelectronic pod inertial navigation system, comprising: obtaining a lever arm length 1 between a GPS signal receiving center and a rotation center of an optoelectronic pod platform, and obtaining a lever arm length 2 between a rotation center of the optoelectronic pod platform and a calculation center of an inertial element; obtaining a conversion matrix 1 and a conversion matrix 2 according to measurement data of platform rotation; obtaining a conversion matrix 3 according to measurement data of an inertial sensitive element; and calculating an effective lever arm according to a lever arm compensation model to perform lever arm compensation.

[0042] The present invention measures the length of the lever arm between the rotation center and the calculation center of the inertial element, obtains a new lever arm for solving the problem during the operation of the optoelectronic pod through coordinate conversion compensation, thereby realizing dynamic lever arm compensation for the inertial navigation of the optoelectronic pod and improving the effective use accuracy during the operation.

[0043] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A dynamic lever arm compensation method for an optoelectronic pod inertial navigation system, characterized in that: include: Obtain the arm length 1 between the GPS signal receiving center and the optoelectronic pod platform rotation center, and obtain the arm length 2 between the optoelectronic pod platform rotation center and the inertial sensor element calculation center; According to the measurement data of the rotation of the optoelectronic pod platform, the conversion matrix from the carrier coordinate system to the inertial sensor coordinate system is obtained. And the transformation matrix from the inertial sensor coordinate system to the carrier coordinate system According to the measurement data of the inertial sensor, the transformation matrix from the inertial sensor coordinate system to the carrier coordinate system is obtained. The effective lever arm is calculated according to the lever arm compensation model as the lever arm of the GPS signal receiving center and the inertial sensitive element calculation center for navigation solution; Get the transformation matrix And the transformation matrix 2 include: The optoelectronic pod platform rotates around ZYX in sequence by angles α, β, and φ. The conversion matrix for: The transformation matrix II for: Get the conversion matrix 3 from the inertial sensor coordinate system to the navigation coordinate system, including: Get the inertial group output attitude angles θ, ψ, γ The transformation matrix three for: The effective lever arm is calculated according to the lever arm compensation model, and the lever arm compensation model is: in is the effective lever arm, is the length of the lever arm, is the arm length two, is the transformation matrix 1, is the transformation matrix 2, is the transformation matrix three.

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