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CN-122015825-A - Navigation precision improving method based on optical fiber inertial measurement unit

CN122015825ACN 122015825 ACN122015825 ACN 122015825ACN-122015825-A

Abstract

The invention discloses a navigation precision improving method based on an optical fiber inertial measurement unit, which comprises the steps of firstly acquiring inertial measurement information through the optical fiber inertial measurement unit, calculating attitude information and speed information of a carrier, secondly calculating navigation attitude information of the carrier according to the attitude information and the speed information of the carrier, then acquiring relative position information of the carrier based on a photoelectric imaging system, establishing a navigation system measurement equation, outputting a result obtained by the navigation system measurement equation as a position error estimated value, and finally carrying out error correction on the navigation attitude information of the carrier according to the position error estimated value, and outputting the result. The method can introduce a photoelectric imaging system to carry out error correction on the navigation pose information measured by the optical fiber inertial measurement unit so as to avoid the error accumulation effect of positioning errors, and the carrier has higher-precision navigation capability.

Inventors

  • ZHANG XIAOFENG

Assignees

  • 北京中航天佑科技有限公司

Dates

Publication Date
20260512
Application Date
20260204

Claims (10)

  1. 1. The navigation precision improving method based on the optical fiber inertial measurement unit is characterized by being applied to navigation of an unmanned aerial vehicle provided with the optical fiber inertial measurement unit, wherein the method comprises the following steps: Acquiring angular velocity information and acceleration information of an optical fiber inertial measurement unit, and calculating attitude information and speed information of a carrier according to the angular velocity information and the acceleration information; Calculating navigation pose information of the carrier according to the pose information and the speed information of the carrier, wherein the navigation pose information of the carrier is used for representing coordinates and angle information of the carrier in a navigation coordinate system at the current moment; acquiring relative position information of the carrier based on the photoelectric imaging system, wherein the relative position information is used for representing the distance and angle of the carrier relative to a target point in the photoelectric imaging system; Establishing a navigation system measurement equation according to navigation pose information and relative position information of the carrier, and outputting a result obtained by the navigation system measurement equation as a position error estimated value; And carrying out error correction on the navigation pose information of the carrier according to the optimal position error estimation value, and outputting the corrected navigation pose information as accurate navigation pose information.
  2. 2. The method for improving navigation accuracy based on an optical fiber inertial measurement unit according to claim 1, wherein calculating navigation pose information of a carrier according to pose information and speed information of the carrier comprises: acquiring inertial navigation position information of a carrier based on the optical fiber inertial measurement unit, wherein the inertial navigation position information of the carrier is used for representing the coordinate position of the carrier in a world coordinate system acquired from the optical fiber inertial measurement unit; Calculating displacement information of the carrier according to the speed information of the carrier; calculating the attitude angle of the carrier according to the attitude information of the carrier; And taking the inertial navigation position information, the displacement information and the attitude angle of the carrier as navigation attitude information of the carrier.
  3. 3. The method for improving navigation accuracy based on an optical fiber inertial measurement unit according to claim 2, wherein acquiring the relative position information of the carrier based on the optoelectronic imaging system comprises: Acquiring characteristic information of each target object by using a photoelectric imaging system, wherein each target object is all objects detected by the photoelectric imaging system; selecting a target object with highest feature matching degree as a target point based on the feature information of each target object; Acquiring a target point navigation coordinate value of a target point in a navigation coordinate system of the carrier, and calculating a geographic position increment and a relative angle of the target point relative to the carrier in a world coordinate system according to the target point navigation coordinate value of the target point; And calculating the relative position information of the carrier according to the geographic position increment and the relative angle of the target point relative to the carrier in the world coordinate system.
  4. 4. The method for improving navigation accuracy based on an optical fiber inertial measurement unit according to claim 3, wherein the step of establishing a navigation system measurement equation according to navigation pose information and relative position information of the carrier comprises the steps of: establishing an error state equation according to the attitude information and the speed information of the carrier, wherein the error state equation comprises a platform error angle equation, a speed error equation, a position error equation and an inertial instrument error equation; calculating a position offset difference value of the carrier according to the relative position information of the carrier and the navigation pose information of the carrier; Establishing a position error measurement equation according to the navigation coordinate value of the target point; And taking the error state equation and the position error measurement equation as navigation system measurement equations, and taking the output quantity of the navigation system measurement equations as the position error estimated value.
  5. 5. The method for improving navigation accuracy based on an optical fiber inertial measurement unit according to claim 1, wherein after outputting a result obtained by a measurement equation of a navigation system as a position error estimated value, further comprising: And performing filtering calculation on the position error estimated value to obtain an optimal position error estimated value.
  6. 6. The method for improving navigation accuracy based on an optical fiber inertial measurement unit according to claim 5, wherein performing a filtering calculation on the position error estimation value to obtain an optimal position error estimation value comprises: Acquiring a position error propagation model; introducing a Gaussian distribution function, and establishing a noise covariance matrix equation based on a position error propagation model; And inputting the position error estimated value into a noise covariance matrix equation, and obtaining the optimal position error estimated value through filtering calculation.
  7. 7. The method for improving navigation accuracy based on an optical fiber inertial measurement unit according to claim 1, wherein performing error correction on navigation pose information of a carrier according to an optimal position error estimation value, and outputting the corrected navigation pose information as accurate navigation pose information, comprises: obtaining a position error correction value according to the optimal position error estimation value; performing superposition calculation on the position error correction value and the navigation pose information of the carrier, and obtaining an error correction result; Updating the navigation pose information of the carrier to be an error correction result; And outputting the updated navigation pose information as accurate navigation pose information at the current moment.
  8. 8. A navigation system based on an optical fiber inertial measurement unit, comprising: the data acquisition module is used for acquiring the angular velocity information and the acceleration information of the optical fiber inertial measurement unit and calculating the attitude information and the speed information of the carrier according to the angular velocity information and the acceleration information of the optical fiber inertial measurement unit; the data processing module is used for calculating navigation pose information of the carrier according to the pose information and the speed information of the carrier, wherein the navigation pose information of the carrier is used for representing the coordinates and the angle information of the carrier in a navigation coordinate system at the current moment; the photoelectric imaging module is used for acquiring relative position information of the carrier based on the photoelectric imaging system, wherein the relative position information is used for representing the distance and the angle of the carrier relative to a target point in the photoelectric imaging system; The error estimation module is used for establishing a navigation system measurement equation according to navigation pose information and relative position information of the carrier, and outputting a result obtained by the navigation system measurement equation as a position error estimation value; The error correction module is used for carrying out error correction on the navigation pose information of the carrier according to the optimal position error estimation value, and outputting the corrected navigation pose information as accurate navigation pose information.
  9. 9. An electronic device, comprising a memory, a processor and a transceiver, which are connected in turn in communication, wherein the memory is used for storing a computer program, the transceiver is used for receiving and transmitting a message, and the processor is used for reading the computer program and executing the navigation precision improving method based on the optical fiber inertial measurement unit according to any one of claims 1-7.
  10. 10. A computer program product comprising a computer program or instructions, characterized in that the computer program or instructions, when executed by a computer, implement the navigation accuracy improvement method based on an optical fiber inertial measurement unit according to any one of claims 1-7.

Description

Navigation precision improving method based on optical fiber inertial measurement unit Technical Field The invention belongs to the technical field of inertial navigation, and particularly relates to a navigation precision improving method based on an optical fiber inertial measurement unit. Background Currently, significant advances have been made in unmanned navigation positioning technology, with the most common and efficient approach being to employ a combined navigation strategy of inertial navigation systems in combination with global satellite navigation systems (GNSS). The combined navigation technology integrates the high short-time precision and stability of the inertial navigation system and the long-distance and high-precision positioning capability of the global satellite navigation system, and provides comprehensive and reliable navigation service for the unmanned aerial vehicle. However, while integrated navigation techniques perform well in many open, unobstructed environments, their performance tends to be severely challenged when faced with complex and diverse urban environments. The urban tall building stands up, the buildings are dense, and the towering structures not only block the direct transmission paths of partial satellite signals, but also interfere the reception of the satellite signals in a reflection, scattering and other modes. Particularly, when the unmanned aerial vehicle flies in urban canyons, the reception intensity and stability of satellite signals are greatly reduced due to the shielding of surrounding buildings. In addition, urban environments are also filled with various electromagnetic interference sources, such as radio broadcasting, mobile communication base stations, power lines and the like, which further weaken the quality of satellite signals, so that unmanned aerial vehicles face the risk of signal failure or significantly reduced positioning accuracy when relying on a global satellite navigation system for positioning. In view of such challenges, if the unmanned aerial vehicle simply relies on the inertial navigation system to navigate, although a certain positioning accuracy can be maintained in a short time, since the working principle of the inertial navigation system is to measure the acceleration and angular velocity of the aircraft based on internal sensors (such as an accelerometer and a gyroscope), and obtain the position and velocity information through integral operation, the positioning error thereof can be accumulated continuously over time. This error accumulation effect is particularly pronounced especially during long flights or long range guidance tasks, which may lead to unmanned aerial vehicles deviating from a predetermined course and even to flight accidents. Therefore, it is needed to provide a navigation accuracy improving method capable of eliminating inertial navigation errors and improving navigation accuracy. Disclosure of Invention The invention aims to provide a navigation precision improving method based on an optical fiber inertial measurement unit, which is used for solving the problems in the prior art. In order to achieve the above purpose, the present invention adopts the following technical scheme: In a first aspect, the present invention provides a navigation accuracy improving method based on an optical fiber inertial measurement unit, which is applied to navigation of an unmanned aerial vehicle provided with the optical fiber inertial measurement unit, wherein the method includes: Acquiring angular velocity information and acceleration information of an optical fiber inertial measurement unit, and calculating attitude information and speed information of a carrier according to the angular velocity information and the acceleration information; Calculating navigation pose information of the carrier according to the pose information and the speed information of the carrier, wherein the navigation pose information of the carrier is used for representing coordinates and angle information of the carrier in a navigation coordinate system at the current moment; acquiring relative position information of the carrier based on the photoelectric imaging system, wherein the relative position information is used for representing the distance and angle of the carrier relative to a target point in the photoelectric imaging system; Establishing a navigation system measurement equation according to navigation pose information and relative position information of the carrier, and outputting a result obtained by the navigation system measurement equation as a position error estimated value; And carrying out error correction on the navigation pose information of the carrier according to the optimal position error estimation value, and outputting the corrected navigation pose information as accurate navigation pose information. In one possible design, calculating navigation pose information of the carrier according to pose information and spe