Inertial navigation error correction method, system and equipment based on reverse navigation solution

Abstract

The invention relates to the technical field of inertial navigation, and provides an inertial navigation error correction method, system and equipment based on inverted navigation resolving, and the method comprises the following steps: recording original data measured by an inertial navigation system in a navigation moment from starting to alignment ending; recording the gyroscopic drift and the initial misalignment angle of the platform estimated by the alignment filter at the navigation moment after the alignment stage is ended; performing navigation solution on the original data based on a time reverse sequence, estimating a gyroscopic drift error according to a reverse sequence navigation result, and performing secondary compensation on the gyroscopic drift and a platform initial misalignment angle error; and performing navigation calculation from the navigation moment based on the compensated platform misalignment angle and gyroscopic drift. According to the method, reverse-sequence navigation calculation is carried out based on parameters obtained by alignment and data recorded in the alignment stage after the alignment moment is finished, and secondary estimation and compensation of drift and misalignment angle errors after the alignment stage are realized based on the calculation result, so that higher navigation precision is obtained.

Description

Technical Field

[0001] This invention relates to the field of inertial navigation technology, and in particular to an inertial navigation error correction method, system and device based on reverse navigation calculation. Background Technology

[0002] Inertial navigation systems (INS) provide a range of navigation information, including position, velocity, and attitude, to a vehicle. INS primarily consists of core inertial components such as gyroscopes and accelerometers. Before navigation, an alignment process is required to align the measurement coordinate system with the navigation calculation coordinate system and assign initial position, velocity, and attitude to the vehicle. Especially for long-endurance INS, gyroscope drift needs to be estimated and compensated for to further improve navigation accuracy. The alignment process typically uses a Kalman filter to estimate the initial state and drift. Due to limitations in inertial component performance and alignment time, errors often exist in the estimated misalignment angle and gyroscope drift during the alignment stage, which determine the accuracy of the final navigation result. Therefore, maximizing alignment accuracy is a core issue that needs to be addressed for long-period INS. Space-stabilized platform inertial navigation systems are a type of platform inertial navigation system. Before navigation, a long alignment process is required to accurately estimate gyroscope drift and platform misalignment angle. However, due to the stabilization process of inertial components after startup, such as gyroscopes and accelerometers, there is still a certain degree of error in the alignment results. These errors are the main factors affecting the long-term navigation accuracy.

[0003] Traditional technologies often fail to fully mine and utilize the raw measurement data from the start-up to the end of the alignment phase, relying solely on preliminary estimates from the alignment filter output for subsequent navigation calculations. This results in the waste of valuable information contained in the raw data and makes it difficult to deeply mine and accurately correct system errors. Existing technologies typically perform gyroscope drift and initial platform misalignment estimation and compensation in a single operation. Due to measurement noise, environmental interference, and limitations of the filter algorithm itself during the alignment phase, single-operation estimation results often contain errors. If these errors are directly used for navigation calculations, they accumulate continuously during subsequent forward navigation, significantly reducing the accuracy and reliability of long-term navigation. This error accumulation problem is particularly pronounced in high-precision navigation scenarios, making it difficult to meet the stringent accuracy requirements of the carrier. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in related technologies. To this end, this invention provides an inertial navigation error correction method, system, and device based on reverse navigation calculation. By performing reverse navigation calculation based on the parameters obtained during alignment and the data recorded during the alignment phase after the alignment time, and by using the calculation results to achieve secondary estimation and compensation for drift and misalignment angle errors after the alignment phase, higher navigation accuracy can be obtained.

[0005] This invention provides an inertial navigation error correction method based on reverse navigation calculation, comprising: S1: Record the raw data measured by the inertial navigation system from startup to the moment of navigation transition after alignment completion; S2: Record the gyro drift and the initial misalignment angle of the platform estimated by the alignment filter at the moment of navigation at the end of the alignment phase; S3: Based on gyroscope drift and the platform's initial misalignment angle, the original data is processed in reverse time order to obtain the reverse navigation result; S4: Estimate the gyroscope drift error based on the reverse navigation results, and perform secondary compensation for the gyroscope drift and the platform's initial misalignment angle error; S5: Based on the compensated platform misalignment angle and gyroscope drift, navigation calculation is performed starting from the navigation moment, and the navigation result is output.

[0006] Furthermore, the inertial navigation system includes a space-stabilized platform inertial navigation system and a non-space-stabilized inertial navigation system. The raw data measured by the system during the time from startup to the end of alignment and transition to navigation in the space-stabilized platform inertial navigation system includes the three-axis acceleration in the platform coordinate system. The raw data measured by the system during the time from startup to the end of alignment and transition to navigation in the non-space-stabilized inertial navigation system includes the acceleration in the platform coordinate system, the angular velocity or angular acceleration measured by the gyroscope, the temperature of the accelerometer, the temperature of the gyroscope, and the frame angle.

[0007] Furthermore, step S3 includes: S31: Based on the gyroscope drift estimate and the platform's initial misalignment angle, calculate the platform's real-time misalignment angle during the alignment process in reverse. S32: Calculate the rotation transformation matrix from the platform coordinate system to the Earth coordinate system based on the platform's real-time misalignment angle; S33: Convert the triaxial acceleration measured in the platform coordinate system to the triaxial acceleration in the Earth coordinate system according to the rotation transformation matrix from the platform coordinate system to the Earth coordinate system; S34: Calculate the gravitational acceleration vector in the Earth coordinate system based on the latitude of the inertial navigation system; S35: Based on the triaxial acceleration and gravitational acceleration vector in the Earth coordinate system, the carrier's velocity and position in the Earth coordinate system are calculated in reverse order to obtain the reverse navigation results.

[0008] Furthermore, step S4 includes: S41: Transform the carrier's position in the Earth coordinate system to the local coordinate system to obtain the latitude and longitude sequence for reverse navigation; S42: Calculate the longitude and latitude errors of the inertial navigation system based on the latitude and longitude sequence of the reverse navigation. S43: Perform curve fitting on the latitude error to obtain the latitude error fitting objective function; S44: Solve for the coefficients of the latitude error fitting objective function to obtain the estimated values ​​of gyro drift error in the x-direction and gyro drift error in the y-direction; S45: Perform curve fitting on the longitude error to obtain the longitude error fitting objective function; S46: Solve for the coefficients of the longitude error fitting objective function to obtain the estimated value of the gyroscope drift error in the z direction.

[0009] Furthermore, the coefficients of the latitude error fitting objective function and the longitude error fitting objective function are solved by the least squares method.

[0010] Furthermore, in step S43, the expression for calculating the latitude error fitting objective function is: in, for Latitude error at any given time This represents the Earth's rotational angular velocity in the Earth coordinate system. The sampling time interval, The first coefficient for latitude error. The second coefficient for latitude error. The third coefficient for latitude error. The fourth coefficient for latitude error. The fifth coefficient for latitude error. The sixth coefficient for latitude error. The seventh coefficient for latitude error. This is the timestamp for the admission data sequence.

[0011] Furthermore, in step S45, the calculation expression for the longitude error fitting objective function is as follows: in, for Longitude error at time The first coefficient for longitude error. The second coefficient for longitude error. The third coefficient for longitude error. The fourth coefficient for longitude error. The fifth coefficient for longitude error. The sixth coefficient for longitude error. Latitude This represents the estimated gyroscope drift error in the x-direction. This represents the estimated gyroscope drift error in the y-direction. This represents the Earth's rotational angular velocity in the Earth coordinate system. The sampling time interval, This is the timestamp for the admission data sequence.

[0012] Furthermore, the platform's real-time misalignment angle estimation formula is updated as follows: in, for The x-axis misalignment angle of the time platform for The y-axis misalignment angle of the time platform for The z-axis misalignment angle of the time platform The initial x-axis misalignment angle of the platform. The initial y-axis misalignment angle of the platform. The initial z-axis misalignment angle of the platform. The sampling time interval, The maximum sampling time, The x-axis component of the gyroscope drift estimate. The y-axis component of the gyroscope drift estimate. The z-axis component of the gyroscope drift estimate. This is the estimated value of the residual error of the gyroscope drift in the x-direction. This represents the estimated gyroscope drift error in the y-direction. This is the estimated value of the gyroscope drift error in the z-direction.

[0013] The present invention also provides an inertial navigation error correction system based on reverse navigation calculation, for executing the above-mentioned inertial navigation error correction method based on reverse navigation calculation, comprising: The first recording module records the raw data measured by the inertial navigation system from startup to the moment of navigation transition after alignment completion. The second recording module records the gyroscope drift estimated by the alignment filter and the initial misalignment angle of the platform at the moment of navigation at the end of the alignment phase. The reverse-order calculation module, based on gyroscope drift and the platform's initial misalignment angle, performs navigation calculations on the original data in reverse time order to obtain reverse-order navigation results; The error estimation and compensation module estimates the gyroscope drift error based on the reverse navigation results and performs secondary compensation for the gyroscope drift and the platform's initial misalignment angle error. The navigation calculation module performs navigation calculations based on the compensated platform misalignment angle and gyroscope drift from the navigation moment and outputs the navigation results.

[0014] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of an inertial navigation error correction method based on reverse navigation calculation as described above.

[0015] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of an inertial navigation error correction method based on reverse navigation calculation as described above.

[0016] The above-described one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: This invention achieves secondary estimation and compensation of drift error by utilizing the acceleration measured after the inertial navigation system starts up and the estimated misalignment angle and initial gyroscope drift value already completed by the system at the navigation turn time. This can effectively improve the navigation accuracy of the inertial navigation system. This invention relies on the original inertial data measured from the start of the system to the start of navigation without adding additional observations or extending the start-up time. It can greatly optimize the estimation accuracy of the inertial navigation system's misalignment angle and gyroscope drift. The algorithm is simple and reliable and can meet the requirements of high-precision navigation.

[0017] The compensation method proposed in this invention can be extended to various types of inertial navigation systems and is applicable to both static and dynamic alignment processes, demonstrating good applicability.

[0018] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a flowchart illustrating an inertial navigation error correction method based on reverse navigation calculation provided by the present invention.

[0021] Figure 2 This is a schematic diagram of the structure of an inertial navigation error correction system based on reverse navigation calculation provided by the present invention.

[0022] Figure 3 This is a block diagram of the electronic device provided by the present invention.

[0023] Figure label: 101. First recording module; 102. Second recording module; 103. Reverse calculation module; 104. Error estimation and compensation module; 105. Navigation calculation module; 201. Processor; 202. Communication bus; 203. Communication interface; 204. Memory. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. The following embodiments are used to illustrate this invention but cannot be used to limit the scope of this invention.

[0025] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0026] The following is combined with Figures 1 to 3 This invention describes an inertial navigation error correction method, system, and device based on reverse navigation calculation.

[0027] like Figure 1 As shown, an inertial navigation error correction method based on reverse navigation calculation includes: S1: Record the raw data measured by the inertial navigation system from startup to the moment of navigation transition after alignment completion; Inertial navigation systems include space-stabilized platform-type inertial navigation systems and non-space-stabilized inertial navigation systems. The raw data measured by the system during the time from startup to the end of alignment and transition to navigation in a space-stabilized platform-type inertial navigation system includes the three-axis acceleration in the platform coordinate system. The raw data measured by the system during the time from startup to the end of alignment and transition to navigation in a non-space-stabilized inertial navigation system includes the acceleration in the platform coordinate system, the angular velocity or angular acceleration measured by the gyroscope, the temperature of the accelerometer, the temperature of the gyroscope, and the frame angle.

[0028] In some specific embodiments of the present invention, the inertial navigation system adopts a four-ring frame space-stabilized platform inertial navigation system. During the alignment process, the space-stabilized platform inertial navigation system only uses the accelerometer output results to estimate and correct gyroscope drift. Therefore, the data to be recorded mainly refers to the triaxial acceleration measured by the accelerometer in the platform coordinate system. At this time, the system switches from alignment mode to navigation mode.

[0029] Start the inertial navigation system and transmit the measurement results from the three-axis accelerometers in the platform coordinate system. Recorded into the navigation calculation computer. ,in, for The x-axis acceleration in the platform coordinate system at any given time. for The y-axis acceleration in the platform coordinate system at any given moment. for The acceleration along the z-axis in the platform coordinate system at any given time. The maximum sampling time, For the timestamp of the admission data sequence, For the transpose of a matrix, when At this time, the system switches from alignment mode to navigation mode.

[0030] S2: Record the gyro drift and the initial misalignment angle of the platform estimated by the alignment filter at the moment of navigation at the end of the alignment phase; The initial navigation state includes the gyroscope drift estimate, the platform's initial misalignment angle, the gyroscope zero bias, and the accelerometer zero bias.

[0031] For different navigation systems, the initial navigation state obtained at the end of the alignment phase and the transition to navigation is not limited to the gyroscope drift estimate. Initial misalignment angle of the platform It may also include parameters such as gyroscope zero bias and accelerometer zero bias; , ,in, The initial x-axis misalignment angle of the platform. The initial y-axis misalignment angle of the platform. The initial z-axis misalignment angle of the platform. The x-axis component of the gyroscope drift estimate. The y-axis component of the gyroscope drift estimate. The z-axis component of the gyroscope drift estimate. This is the transpose of the matrix; The inertial navigation system successfully completed the system alignment process during startup, and the estimated gyroscope drift values ​​obtained during the alignment process were transmitted. Initial misalignment angle of the platform Recorded in the navigation computer; S3: Based on gyroscope drift and the platform's initial misalignment angle, the original data is processed in reverse time order to obtain the reverse navigation result; S31: Based on the gyroscope drift estimate and the platform's initial misalignment angle, the real-time misalignment angle of the platform during the alignment process is calculated in reverse. The calculation expression is: in, for The x-axis misalignment angle of the time platform for The y-axis misalignment angle of the time platform for The z-axis misalignment angle of the time platform The sampling time interval, This is the maximum sampling time; S32: Calculate the rotation transformation matrix from the platform coordinate system to the Earth coordinate system based on the platform's real-time misalignment angle. The calculation expression is as follows: in, for The rotation transformation matrix from the platform coordinate system to the Earth coordinate system at any time; S33: Convert the triaxial acceleration measured in the platform coordinate system to the triaxial acceleration in the Earth coordinate system according to the rotation transformation matrix from the platform coordinate system to the Earth coordinate system; in, for The x-axis acceleration in the Earth coordinate system at any given moment. for Acceleration along the y-axis in the Earth coordinate system at any given moment. for The acceleration along the z-axis in the Earth coordinate system at time [time]. for The x-axis acceleration in the platform coordinate system at any given time. for The y-axis acceleration in the platform coordinate system at any given moment. for The acceleration along the z-axis in the platform coordinate system at any given time. for The rotation transformation matrix from the platform coordinate system to the Earth coordinate system at any time; S34: Calculate the gravitational acceleration vector in the Earth coordinate system based on the latitude of the inertial navigation system; in, for The x-axis component of the gravitational acceleration vector in the Earth coordinate system at any given moment. for The y-axis component of the gravitational acceleration vector in the Earth coordinate system at any given time. for The z-axis component of the gravitational acceleration vector in the Earth coordinate system at any given time. Local gravitational acceleration, Latitude; S35: Based on the triaxial acceleration and gravitational acceleration vector in the Earth coordinate system, the carrier's velocity and position in the Earth coordinate system are calculated in reverse order to obtain the reverse navigation results. The expression for calculating the velocity of the carrier in the Earth coordinate system by inversely solving for the triaxial acceleration and gravitational acceleration vector in the Earth coordinate system is as follows: in, for Download the x-axis component of the volumetric velocity in the Earth coordinate system at any given time. for Download the y-axis component of the velocity of the body in the Earth coordinate system at any given time. for Download the z-axis component of the volumetric velocity in the Earth coordinate system at any given time. This is the x-axis projection of the Earth's rotational angular velocity in the Earth coordinate system. This is the y-axis projection of the Earth's rotational angular velocity in the Earth coordinate system. This is the z-axis projection of the Earth's rotational angular velocity in the Earth coordinate system. for Download the x-axis component of the volumetric velocity in the Earth coordinate system at any given time. for Download the y-axis component of the velocity of the body in the Earth coordinate system at any given time. for Download the z-axis component of the volumetric velocity in the Earth coordinate system at any given moment; Reverse solution from Beginning, until Finish; The calculation expression for inversely calculating the position of the carrier in the Earth coordinate system based on the triaxial acceleration and gravitational acceleration vector in the Earth coordinate system is as follows: in, for Position on the x-axis in the Earth coordinate system at any given time. for Position on the y-axis in the Earth coordinate system at any given time. for Position of the z-axis in the Earth coordinate system at any given time. is the x-axis position in the Earth coordinate system at time is the y-axis position in the Earth coordinate system at time is the z-axis position in the Earth coordinate system at time ; The inverse-order calculation starts from and ends at ; S4: Estimate the gyro drift error based on the inverse-order navigation result, and perform secondary compensation on the gyro drift and the initial misalignment angle error of the platform; S41: Convert the carrier position in the Earth coordinate system to the local coordinate system to obtain the longitude and latitude sequence of the inverse-order navigation; After the navigation calculation is completed, convert the carrier position in the Earth coordinate system to the local coordinate system. The calculation formula is: where, is the latitude at time is the longitude at time is the horizontal height at time is the Earth eccentricity, is the radius of curvature of the prime vertical, is the arctangent function; The longitude and latitude sequence obtained through inverse-order navigation can be expressed as: where, is the longitude constant term coefficient, is the longitude cosine first-order term coefficient, is the longitude cosine second-order term coefficient, is the Earth's angular velocity of rotation in the Earth coordinate system, is the longitude sine first-order term coefficient, ]>is the longitude sine second-order term coefficient, is the latitude constant term coefficient, is the latitude cosine first-order term coefficient, is the latitude cosine second-order term coefficient, is the latitude sine first-order term coefficient, is the latitude sine second-order term coefficient, is the time corresponding to time ; ]>S42: Calculate the longitude error and latitude error of the inertial navigation based on the longitude and latitude sequence of the reverse navigation; The longitude error of the inertial navigation system is: in, for Longitude error at time This is the initial longitude; The latitude error of the inertial navigation system is: in, for Latitude error at any given time Initial latitude; S43: Perform curve fitting on the latitude error to obtain the objective function for latitude error fitting. The expression for the objective function for latitude error fitting is as follows: in, for Latitude error at any given time This represents the Earth's rotational angular velocity in the Earth coordinate system. The sampling time interval, The first coefficient for latitude error. The second coefficient for latitude error. The third coefficient for latitude error. The fourth coefficient for latitude error. The fifth coefficient for latitude error. The sixth coefficient for latitude error. This is the seventh coefficient for latitude error.

[0032] S44: Solve for the coefficients of the latitude error fitting objective function to obtain the estimated values ​​of gyro drift error in the x-direction and gyro drift error in the y-direction; The latitude error fitting objective function is solved using the least squares method. Based on the latitude and longitude error sequences obtained from reverse navigation, the matrix form can be constructed as follows: in, for Latitude error at time for Latitude error at that time; Express it in matrix form as follows: in, The coefficient matrix, Let be the column vector of coefficients to be estimated. It is a constant vector; By using the least squares method, the coefficients to be estimated can be obtained: The obtained coefficients The estimated value of the gyroscope drift error in the y-direction , The estimated value of the gyroscope drift error in the x-direction ; S45: Perform curve fitting on the longitude error to obtain the longitude fitting objective function; the calculation expression of the longitude fitting objective function is: in, for Longitude error at time The first coefficient for longitude error. The second coefficient for longitude error. The third coefficient for longitude error. The fourth coefficient for longitude error. The fifth coefficient for longitude error. The sixth coefficient for longitude error. Latitude This represents the estimated gyroscope drift error in the x-direction. This is the estimated value of the gyroscope drift error in the y-direction.

[0033] S46: Solve for the coefficients of the longitude fitting objective function to obtain the estimated value of the gyroscope drift error in the z direction; The coefficients are obtained by solving the longitude fitting objective function using the least squares method. The estimated value of the gyroscope drift error in the z-direction The method is the same. and The solution will not be elaborated here.

[0034] Compensation is provided for gyroscope drift based on gyroscope drift error.

[0035] The platform's real-time misalignment angle is compensated based on the gyroscope drift error, and the estimation formula for the platform's real-time misalignment angle is updated as follows: in, for The x-axis misalignment angle of the time platform for The y-axis misalignment angle of the time platform for The z-axis misalignment angle of the time platform The initial x-axis misalignment angle of the platform. The initial y-axis misalignment angle of the platform. The initial z-axis misalignment angle of the platform. The sampling time interval, The maximum sampling time, The x-axis component of the gyroscope drift estimate. The y-axis component of the gyroscope drift estimate. The z-axis component of the gyroscope drift estimate. This represents the estimated residual error of the gyroscope drift in the x-direction. This represents the estimated gyroscope drift error in the y-direction. This is the estimated value of the gyroscope drift error in the z-direction.

[0036] S5: Based on the compensated platform misalignment angle and gyroscope drift, navigation calculation is performed starting from the navigation moment, and the navigation result is output.

[0037] By performing reverse navigation calculations based on the parameters obtained from alignment and the data recorded during the alignment phase after the alignment time has ended, and by calculating and compensating for the gyroscope drift estimation error after the alignment phase based on the calculation results, the alignment accuracy of the inertial navigation system can be improved.

[0038] like Figure 2 As shown, an inertial navigation error correction system based on reverse navigation calculation is used to execute the aforementioned inertial navigation error correction method based on reverse navigation calculation, including: The first recording module 101 records the raw data measured by the inertial navigation system from startup to the moment of navigation transition after alignment completion. The second recording module 102 records the gyroscope drift and the initial misalignment angle of the platform estimated by the alignment filter at the moment of navigation after the alignment phase ends. The reverse-order calculation module 103 performs navigation calculations on the raw data in reverse time order based on gyroscope drift and the platform's initial misalignment angle to obtain reverse-order navigation results; The error estimation and compensation module 104 estimates the gyroscope drift error based on the reverse navigation results and performs secondary compensation for the gyroscope drift and the platform's initial misalignment angle error. The navigation calculation module 105 performs navigation calculations based on the compensated platform misalignment angle and gyroscope drift from the navigation moment and outputs the navigation results.

[0039] Through the coordinated work of the above modules, and by utilizing the acceleration measured after the inertial navigation system starts up and the initial values ​​of the misalignment angle and gyroscope drift estimated by the system at the turn navigation time, a secondary estimation and compensation of drift error is achieved, which can effectively improve the navigation accuracy of the inertial navigation system. This invention relies on the original inertial data measured from the start of the system to the start of navigation, without adding additional observations or extending the start-up time, which can greatly optimize the estimation accuracy of the inertial navigation system's misalignment angle and gyroscope drift. The algorithm is simple and reliable and can meet the requirements of high-precision navigation.

[0040] The compensation method proposed in this invention can be extended to various types of inertial navigation systems and is applicable to both static and dynamic alignment processes, demonstrating good applicability.

[0041] Figure 3 An example is a block diagram of an electronic device, such as... Figure 3 As shown, the electronic device may include a processor 201, a communication interface 203, a memory 204, and a communication bus 202. The processor 201, communication interface 203, and memory 204 communicate with each other via the communication bus 202. The processor 201 can call logical instructions from the memory 204 to execute an inertial navigation error correction method based on reverse navigation calculation.

[0042] Furthermore, the logical instructions in the aforementioned memory 204 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0043] On the other hand, the present invention also provides a computer program product, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, and when the program instructions are executed by a computer, the computer is able to execute an inertial navigation error correction method based on reverse navigation calculation provided by the above methods.

[0044] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements an inertial navigation error correction method based on reverse navigation calculation provided by the above methods.

[0045] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0046] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for correcting inertial navigation errors based on reverse navigation calculation, characterized in that, include: S1: Record the raw data measured by the inertial navigation system from startup to the moment of navigation transition after alignment completion; S2: Record the gyro drift and the initial misalignment angle of the platform estimated by the alignment filter at the moment of navigation at the end of the alignment phase; S3: Based on gyroscope drift and the platform's initial misalignment angle, the original data is processed in reverse time order to obtain the reverse navigation result; S4: Estimate the gyroscope drift error based on the reverse navigation results, and perform secondary compensation for the gyroscope drift and the platform's initial misalignment angle error; S5: Based on the compensated platform misalignment angle and gyroscope drift, navigation calculation is performed starting from the navigation moment, and the navigation result is output.

2. The inertial navigation error correction method based on reverse navigation solution according to claim 1, characterized in that, Inertial navigation systems include space-stabilized platform-type inertial navigation systems and non-space-stabilized inertial navigation systems. The raw data measured by the system during the time from startup to the end of alignment and transition to navigation in a space-stabilized platform-type inertial navigation system includes the three-axis acceleration in the platform coordinate system. The raw data measured by the system during the time from startup to the end of alignment and transition to navigation in a non-space-stabilized inertial navigation system includes the acceleration in the platform coordinate system, the angular velocity or angular acceleration measured by the gyroscope, the temperature of the accelerometer, the temperature of the gyroscope, and the frame angle.

3. The inertial navigation error correction method based on reverse navigation calculation according to claim 2, characterized in that, Step S3 includes: S31: Based on the gyroscope drift estimate and the platform's initial misalignment angle, calculate the platform's real-time misalignment angle during the alignment process in reverse. S32: Calculate the rotation transformation matrix from the platform coordinate system to the Earth coordinate system based on the platform's real-time misalignment angle; S33: Convert the triaxial acceleration measured in the platform coordinate system to the triaxial acceleration in the Earth coordinate system according to the rotation transformation matrix from the platform coordinate system to the Earth coordinate system; S34: Calculate the gravitational acceleration vector in the Earth coordinate system based on the latitude of the inertial navigation system; S35: Based on the three-axis acceleration and gravitational acceleration vector in the Earth coordinate system, the carrier's velocity and position in the Earth coordinate system are calculated in reverse order to obtain the reverse navigation results.

4. The inertial navigation error correction method based on reverse navigation solution according to claim 1, characterized in that, Step S4 includes: S41: Transform the carrier's position in the Earth coordinate system to the local coordinate system to obtain the latitude and longitude sequence for reverse navigation; S42: Calculate the longitude and latitude errors of the inertial navigation system based on the latitude and longitude sequence of the reverse navigation. S43: Perform curve fitting on the latitude error to obtain the latitude error fitting objective function; S44: Solve for the coefficients of the latitude error fitting objective function to obtain the estimated values ​​of gyro drift error in the x-direction and gyro drift error in the y-direction; S45: Perform curve fitting on the longitude error to obtain the longitude error fitting objective function; S46: Solve for the coefficients of the longitude error fitting objective function to obtain the estimated value of the gyroscope drift error in the z direction.

5. The inertial navigation error correction method based on reverse navigation solution according to claim 4, characterized in that, The coefficients of the latitude error fitting objective function and the longitude error fitting objective function are obtained by using the least squares method.

6. The inertial navigation error correction method based on reverse navigation solution according to claim 4, characterized in that, In step S43, the calculation expression for the latitude error fitting objective function is as follows: in, for Latitude error at any given time This represents the Earth's rotational angular velocity in the Earth coordinate system. The sampling time interval, The first coefficient for latitude error. The second coefficient for latitude error. The third coefficient for latitude error. The fourth coefficient for latitude error. The fifth coefficient for latitude error. The sixth coefficient for latitude error. The seventh coefficient for latitude error. This is the timestamp for the admission data sequence.

7. The inertial navigation error correction method based on reverse navigation solution according to claim 4, characterized in that, In step S45, the calculation expression for the longitude error fitting objective function is as follows: in, for Longitude error at time The first coefficient for longitude error. The second coefficient for longitude error. The third coefficient for longitude error. The fourth coefficient for longitude error. The fifth coefficient for longitude error. The sixth coefficient for longitude error. Latitude This represents the estimated gyroscope drift error in the x-direction. This represents the estimated gyroscope drift error in the y-direction. This represents the Earth's rotational angular velocity in the Earth coordinate system. The sampling time interval, This is the timestamp for the admission data sequence.

8. The inertial navigation error correction method based on reverse navigation solution according to claim 1, characterized in that, The platform's real-time misalignment angle estimation formula has been updated to: in, for The x-axis misalignment angle of the time platform for The y-axis misalignment angle of the time platform for The z-axis misalignment angle of the time platform The initial x-axis misalignment angle of the platform. The initial y-axis misalignment angle of the platform. The initial z-axis misalignment angle of the platform. The sampling time interval, The maximum sampling time, The x-axis component of the gyroscope drift estimate. The y-axis component of the gyroscope drift estimate. The z-axis component of the gyroscope drift estimate. This is the estimated value of the residual error of the gyroscope drift in the x-direction. This represents the estimated gyroscope drift error in the y-direction. This is the estimated value of the gyroscope drift error in the z-direction.

9. An inertial navigation error correction system based on reverse navigation calculation, characterized in that, To perform an inertial navigation error correction method based on reverse navigation calculation as described in any one of claims 1 to 8, comprising: The first recording module records the raw data measured by the inertial navigation system from startup to the moment of navigation transition after alignment completion. The second recording module records the gyroscope drift estimated by the alignment filter and the initial misalignment angle of the platform at the moment of navigation at the end of the alignment phase. The reverse-order calculation module, based on gyroscope drift and the platform's initial misalignment angle, performs navigation calculations on the original data in reverse time order to obtain reverse-order navigation results; The error estimation and compensation module estimates the gyroscope drift error based on the reverse navigation results and performs secondary compensation for the gyroscope drift and the platform's initial misalignment angle error. The navigation calculation module performs navigation calculations based on the compensated platform misalignment angle and gyroscope drift from the navigation moment and outputs the navigation results.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the inertial navigation error correction method based on reverse navigation calculation as described in any one of claims 1 to 8.

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