An inertial navigation error correction method, system and device based on reverse sequence navigation solution

Abstract

The present application relates to the technical field of inertial navigation, and provides an inertial navigation error correction method, system and device based on reverse sequence navigation solution, which comprises the following steps: recording original data measured by an inertial navigation system from starting to the end of alignment and into navigation time; recording gyro drift and platform initial misalignment angle estimated by an alignment filter at the end of alignment and into navigation time; performing navigation solution on the original data based on time reverse sequence, estimating gyro drift error according to reverse sequence navigation result, and performing secondary compensation on gyro drift and platform initial misalignment angle error; and performing navigation solution based on compensated platform misalignment angle and gyro drift from navigation time. The present application performs reverse sequence navigation solution based on alignment parameters and data recorded in the alignment stage after the end of alignment, and realizes secondary estimation and compensation of drift and misalignment angle error after the alignment stage based on the solution result, so as to obtain higher navigation precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of inertial navigation, and in particular to an inertial navigation error correction method, system and device based on reverse sequence navigation solution. BACKGROUND

[0002] An inertial navigation system can provide a carrier with a series of navigation information such as position, speed and attitude. The inertial navigation system mainly consists of core inertial elements such as gyroscopes and accelerometers. Before navigation, the measurement coordinate system needs to be aligned with the navigation solution coordinate system through the alignment process, and the initial position, speed and attitude of the carrier are given. Especially for long-haul inertial navigation systems, the gyro drift needs to be estimated and compensated to further improve the navigation accuracy. The alignment process of the inertial navigation system generally uses a Kalman filter to estimate the initial state and drift. Due to the performance of the inertial element and the alignment time limit, the misalignment angle and gyro drift estimated in the alignment phase often have errors, which determine the accuracy of the final navigation result. Therefore, how to improve the alignment accuracy as much as possible is a core problem that needs to be solved for long-period inertial navigation systems. The space-stabilized platform inertial navigation system belongs to a platform inertial navigation system. Before navigation, a long alignment process is needed to complete the accurate estimation of the gyro drift and the platform misalignment angle. However, due to the influence of the stabilization process of the inertial element after startup, such as gyroscopes and accelerometers, there is still a certain degree of error in the alignment result, and these errors are the main factors affecting the long-period navigation accuracy.

[0003] Traditional technologies often fail to fully exploit and utilize the original measurement data from the startup to the end of the alignment phase, and only rely on the preliminary estimated parameters output by the alignment filter for subsequent navigation solution, resulting in the waste of effective information contained in the original data and the difficulty in achieving deep mining and accurate correction of system errors. The estimation and compensation of gyro drift and platform initial misalignment angle in the prior art are mostly completed once. Due to the measurement noise in the alignment phase, environmental interference and the limitations of the filter algorithm itself, the single estimation result often has a certain error. If it is directly used for navigation solution, the error will be accumulated in the subsequent forward navigation process, significantly reducing the long-term navigation accuracy and reliability. Especially in high-precision navigation demand scenarios, the error accumulation problem of traditional technologies is more prominent, and it is difficult to meet the stringent requirements of the carrier on navigation accuracy. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the related art. To this end, the present application provides an inertial navigation error correction method, system and device based on reverse sequence navigation solution, which performs reverse sequence navigation solution based on the alignment parameters and the data recorded during the alignment phase after the end of the alignment time, and realizes secondary estimation and compensation of the drift and misalignment angle error after the alignment phase based on the solution result, to obtain higher navigation accuracy.

[0005] The application provides an inertial navigation error correction method based on reverse sequence navigation solution, comprising:

[0006] S1: recording original data measured by the inertial navigation system from start to alignment end to navigation time;

[0007] S2: recording gyro drift and platform initial misalignment angle estimated by the alignment filter at the alignment end to navigation time;

[0008] S3: based on the gyro drift and the platform initial misalignment angle, performing navigation solution on the original data based on time reverse sequence to obtain reverse sequence navigation result;

[0009] S4: estimating gyro drift error according to the reverse sequence navigation result, and performing secondary compensation on the gyro drift and the platform initial misalignment angle error;

[0010] S5: performing navigation solution based on the compensated platform misalignment angle and the gyro drift from the navigation time to output navigation result.

[0011] Further, the inertial navigation system comprises a space-stabilized platform inertial navigation system and a non-space-stabilized inertial navigation system, the original data measured by the space-stabilized platform inertial navigation system from start to alignment end to navigation time comprises three-axis acceleration in the platform coordinate system, and the original data measured by the non-space-stabilized inertial navigation system from start to alignment end to navigation time comprises acceleration in the platform coordinate system, angular velocity or angular acceleration measured by the gyroscope, temperature of the accelerometer, temperature of the gyroscope and frame angle.

[0012] Further, S3 step comprises:

[0013] S31: inversely solving real-time misalignment angle of the platform in the alignment process according to the gyro drift estimation value and the platform initial misalignment angle;

[0014] S32: calculating rotation transformation matrix from the platform coordinate system to the earth coordinate system according to the real-time misalignment angle of the platform;

[0015] S33: converting three-axis acceleration measured in the platform coordinate system to three-axis acceleration in the earth coordinate system according to the rotation transformation matrix from the platform coordinate system to the earth coordinate system;

[0016] S34: calculating gravity acceleration vector in the earth coordinate system according to the latitude of the inertial navigation system;

[0017] S35: inversely solving carrier motion velocity in the earth coordinate system and carrier position in the earth coordinate system according to three-axis acceleration in the earth coordinate system and the gravity acceleration vector in the earth coordinate system to obtain reverse sequence navigation result.

[0018] Further, the S4 step comprises:

[0019] S41: converting the carrier position in the earth coordinate system into the local coordinate system to obtain a longitude and latitude sequence of reverse navigation;

[0020] S42: calculating the longitude error and the latitude error of the inertial navigation according to the longitude and latitude sequence of reverse navigation;

[0021] S43: performing curve fitting on the latitude error to obtain a latitude error fitting target function;

[0022] S44: solving the coefficients of the latitude error fitting target function to obtain the estimated value of the gyro drift error in the x direction and the estimated value of the gyro drift error in the y direction;

[0023] S45: performing curve fitting on the longitude error to obtain a longitude error fitting target function;

[0024] S46: solving the coefficients of the longitude error fitting target function to obtain the estimated value of the gyro drift error in the z direction.

[0025] Further, the coefficients of the latitude error fitting target function and the coefficients of the longitude error fitting target function are solved by the least square method.

[0026] Further, in the S43 step, the calculation expression of the latitude error fitting target function is:

[0027]

[0028] wherein, is the latitude error at the time t, is the earth rotation angular velocity in the earth coordinate system, is the sampling time interval, is the first coefficient of the latitude error, is the second coefficient of the latitude error, is the third coefficient of the latitude error, is the fourth coefficient of the latitude error, is the fifth coefficient of the latitude error, is the sixth coefficient of the latitude error, is the seventh coefficient of the latitude error, is the time stamp of the data sequence. Further, in the S45 step, the calculation expression of the longitude error fitting target function is:

[0029]

[0030] wherein,

[0031] is the longitude error at the time t, is the earth rotation angular velocity in the earth coordinate system, longitude error at time t, is a first coefficient of longitude error, is a second coefficient of longitude error, is a third coefficient of longitude error, is a fourth coefficient of longitude error, is a fifth coefficient of longitude error, is a sixth coefficient of longitude error, is latitude, is an estimated value of x-direction gyro drift error, is an estimated value of y-direction gyro drift error, is an angular velocity of earth rotation in the earth coordinate system, is a sampling time interval, is a time stamp of the recorded data sequence.

[0032] Further, the platform real-time misalignment angle estimation formula is updated as:

[0033]

[0034] wherein, is a platform x-axis misalignment angle at time t, is a platform y-axis misalignment angle at time t, is a platform z-axis misalignment angle at time t, is a platform x-axis misalignment angle at initial time, is a platform y-axis misalignment angle at initial time, is a platform z-axis misalignment angle at initial time, is a sampling time interval, is a maximum sampling time, is an x-axis component of gyro drift estimation value, is a y-axis component of gyro drift estimation value, is a z-axis component of gyro drift estimation value, is an estimated value of x-direction gyro drift residual error, is an estimated value of y-direction gyro drift error, is an estimated value of z-direction gyro drift error.

[0035] The application also provides an inertial navigation error correction system based on reverse sequence navigation solution, which is used to execute the above-mentioned inertial navigation error correction method based on reverse sequence navigation solution, and comprises:

[0036] a first recording module, which records original data measured by the inertial navigation system from startup to alignment end and then to navigation time;

[0037] a second recording module, configured to record the gyro drift and the initial misalignment angle of the platform estimated by the alignment filter at the end of the alignment phase;

[0038] a reverse sequence solving module, configured to solve the original data based on time in reverse sequence based on the gyro drift and the initial misalignment angle of the platform, and obtain a reverse sequence navigation result;

[0039] an error estimation and compensation module, configured to estimate the gyro drift error based on the reverse sequence navigation result, and compensate the gyro drift and the initial misalignment angle of the platform error for a second time;

[0040] a navigation solving module, configured to solve the navigation from the navigation time based on the compensated misalignment angle of the platform and the gyro drift, and output a navigation result.

[0041] The application further provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the above-mentioned any one kind of inertial navigation error correction method based on reverse sequence navigation solving when executing the program.

[0042] The application further provides a non-transient computer readable storage medium, which stores a computer program, and the computer program implements the steps of the above-mentioned any one kind of inertial navigation error correction method based on reverse sequence navigation solving when executed by a processor.

[0043] The above-mentioned one or more technical solutions in the embodiments of the application have at least one of the following technical effects:

[0044] The application realizes the secondary estimation and compensation of the drift error by twice using the acceleration measured after the start of the inertial navigation system and the misalignment angle and the initial value of the gyro drift estimated by the system at the time of the turn navigation, can effectively improve the navigation precision of the inertial navigation system; the original inertial data measured from the start of the system to the start of the navigation is used in the application, and no additional observation or extended start time is added, which can greatly optimize the estimation precision of the misalignment angle and the gyro drift of the inertial navigation system, the algorithm is simple and reliable, and can meet the demand of high-precision navigation.

[0045] The compensation method proposed in the application can be popularized to various types of inertial navigation systems, and is applicable to the static alignment and dynamic alignment processes, and has good popularization applicability.

[0046] Additional aspects and advantages of the application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without any creative effort.

[0048] Figure 1 is a flowchart of a kind of inertial navigation error correction method based on reverse sequence navigation solution provided by the present application.

[0049] Figure 2 is the structure diagram of a kind of inertial navigation error correction system based on reverse sequence navigation solution provided by the present application.

[0050] Figure 3 is the block diagram of electronic equipment provided by the present application.

[0051] Reference signs:

[0052] 101, first recording module; 102, second recording module; 103, reverse sequence solution module; 104, error estimation and compensation module; 105, navigation solution module; 201, processor; 202, communication bus; 203, communication interface; 204, memory. DETAILED DESCRIPTION

[0053] So that the purpose, technical solutions and advantages of the present application are more clear, the technical solutions in the present application will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative effort are within the scope of protection of the present application. The following embodiments are used to illustrate the present application, but cannot be used to limit the scope of the present application.

[0054] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms is not necessarily for the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable way in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of different embodiments or examples without contradiction.

[0055] The following will be combined with Figures 1 to 3The application discloses an inertial navigation error correction method based on reverse sequence navigation solution, a system and equipment thereof.

[0056] As shown in the drawings, Figure 1 a kind of inertial navigation error correction method based on reverse sequence navigation solution, comprising:

[0057] S1: record the original data measured by inertial navigation system from start to end of alignment into navigation time system measurement;

[0058] Inertial navigation system includes space stable platform type inertial navigation system and non-space stable inertial navigation system, and the original data measured by space stable platform type inertial navigation system from start to end of alignment into navigation time system measurement includes three-axis acceleration in platform coordinate system, and the original data measured by non-space stable inertial navigation system from start to end of alignment into navigation time system measurement includes acceleration in platform coordinate system, angular velocity or angular acceleration measured by gyroscope, temperature of accelerometer, temperature of gyroscope and frame angle.

[0059] In some specific embodiments of the application, the inertial navigation system adopts four-ring frame space stable platform type inertial navigation system, and the space stable platform type inertial navigation system only applies accelerometer output results to estimate and correct gyroscope drift in the alignment process, so the data to be recorded mainly refers to three-axis acceleration measured by accelerometer in platform coordinate system. When

[0060] Start inertial navigation system, and record the measurement results of three-axis accelerometer in platform coordinate system into navigation solution computer, Wherein, When is x-axis acceleration in platform coordinate system at time, is y-axis acceleration in platform coordinate system at time, is z-axis acceleration in platform coordinate system at time, is the maximum sampling time, is the time stamp of data sequence, is the transpose of matrix, and When S2: record the gyroscope drift estimated by alignment filter and the initial misalignment angle of platform at the end of alignment into navigation time;

[0061] Navigation initial state includes gyroscope drift estimation value, initial misalignment angle of platform, gyroscope zero offset and accelerometer zero offset.

[0062]

[0063] ​​​For different navigation systems, the initial navigation state obtained at the end of the alignment stage is not limited to the estimated value of the gyro drift and the initial misalignment angle of the platform , and may also include the gyro zero offset, the accelerometer zero offset, and other parameters. , wherein, is the initial misalignment angle of the platform x-axis, is the initial misalignment angle of the platform y-axis, is the initial misalignment angle of the platform z-axis, is the x-axis component of the estimated value of the gyro drift, is the y-axis component of the estimated value of the gyro drift, is the z-axis component of the estimated value of the gyro drift, is the transpose of the matrix;

[0064] The inertial navigation system normally completes the system alignment process during the startup process, and records the estimated value of the gyro drift estimated in the alignment process and the initial misalignment angle of the platform in the navigation computer.

[0065] S3: Based on the gyro drift and the initial misalignment angle of the platform, the original data is inversely sequenced based on time for navigation calculation, and the inverse sequence navigation result is obtained.

[0066] S31: According to the estimated value of the gyro drift and the initial misalignment angle of the platform, the real-time misalignment angle of the platform in the alignment process is inversely calculated, and the calculation expression is:

[0067]

[0068] wherein, is the real-time misalignment angle of the platform x-axis, is the real-time misalignment angle of the platform y-axis, is the real-time misalignment angle of the platform z-axis, is the sampling time interval, is the maximum sampling time; S32: According to the real-time misalignment angle of the platform, the rotation transformation matrix from the platform coordinate system to the earth coordinate system is calculated, and the calculation expression is:

[0069]

[0070] wherein, is the rotation transformation matrix from the platform coordinate system to the earth coordinate system at the time t;

[0071]

[0072] ​​​​S33: converting the three-axis acceleration measured in the platform coordinate system to three-axis acceleration in the earth coordinate system according to the rotation transformation matrix from the platform coordinate system to the earth coordinate system;

[0073]

[0074] wherein, is the x-axis acceleration in the earth coordinate system at time t, is the y-axis acceleration in the earth coordinate system at time t, is the z-axis acceleration in the earth coordinate system at time t, is the x-axis acceleration in the platform coordinate system at time t, is the y-axis acceleration in the platform coordinate system at time t, is the z-axis acceleration in the platform coordinate system at time t, is the rotation transformation matrix from the platform coordinate system to the earth coordinate system at time t, is the x-axis acceleration in the platform coordinate system at time t, is the y-axis acceleration in the platform coordinate system at time t, is the z-axis acceleration in the platform coordinate system at time t, is the rotation transformation matrix from the platform coordinate system to the earth coordinate system at time t, is the x-axis acceleration in the platform coordinate system at time t, is the y-axis acceleration in the platform coordinate system at time t, is the z-axis acceleration in the platform coordinate system at time t,

[0075] S34: calculating the gravity acceleration vector in the earth coordinate system according to the latitude of the inertial navigation system;

[0076]

[0077] wherein, is the x-axis component of the gravity acceleration vector in the earth coordinate system at time t, is the y-axis component of the gravity acceleration vector in the earth coordinate system at time t, is the z-axis component of the gravity acceleration vector in the earth coordinate system at time t, is the local gravity acceleration, is the latitude; S35: inversely solving the carrier motion velocity in the earth coordinate system and the carrier position in the earth coordinate system according to the three-axis acceleration in the earth coordinate system and the gravity acceleration vector in the earth coordinate system, to obtain the inverse navigation result; The calculation expression for inversely solving the carrier motion velocity in the earth coordinate system according to the three-axis acceleration in the earth coordinate system and the gravity acceleration vector in the earth coordinate system is:

[0078]

[0079]

[0080]

[0081] wherein, is the carrier motion velocity in the earth coordinate system at time t,​​​ the x-axis component of the body motion velocity in the earth coordinate system at time t, the y-axis component of the body motion velocity in the earth coordinate system at time t, the z-axis component of the body motion velocity in the earth coordinate system at time t, the x-axis projection of the earth rotation angular velocity in the earth coordinate system, the y-axis projection of the earth rotation angular velocity in the earth coordinate system, the z-axis projection of the earth rotation angular velocity in the earth coordinate system, the x-axis component of the body motion velocity in the earth coordinate system at time t, the y-axis component of the body motion velocity in the earth coordinate system at time t, the z-axis component of the body motion velocity in the earth coordinate system at time t;

[0082] the inverse sequence solution is solved from to ;

[0083] the calculation expression for inversely solving the body position in the earth coordinate system according to the three-axis acceleration in the earth coordinate system and the gravity acceleration vector in the earth coordinate system is:

[0084]

[0085] wherein, the x-axis position in the earth coordinate system at time t, the y-axis position in the earth coordinate system at time t, the z-axis position in the earth coordinate system at time t, the x-axis position in the earth coordinate system at time t, the y-axis position in the earth coordinate system at time t, the z-axis position in the earth coordinate system at time t;

[0086] the inverse sequence solution is solved from to ;

[0087] S4: estimating the gyro drift error according to the inverse sequence navigation result, and performing secondary compensation on the gyro drift and the platform initial misalignment angle error;

[0088] ​​​​​​​​​​​S41: Convert the carrier position in the earth coordinate system to the local coordinate system to obtain the longitude and latitude sequence for reverse navigation;

[0089] After the navigation solution is completed, convert the carrier position in the earth coordinate system to the local coordinate system. The calculation formula is:

[0090]

[0091] 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;

[0092] The longitude and latitude sequence obtained through reverse navigation can be expressed as:

[0093]

[0094] where, is the longitude constant term coefficient, is the longitude cosine first-order term coefficient, is the longitude cosine second-order term coefficient, is 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 ;

[0095] S42: Calculate the longitude error and latitude error of the inertial navigation according to the longitude and latitude sequence of the reverse navigation;

[0096] The longitude error of the inertial navigation is:

[0097]

[0098] where, is the longitude error at time is the initial longitude;

[0099] The latitude error of the inertial navigation is:

[0100]

[0101] wherein, is the latitude error at time t, is the latitude error at time t, is the initial latitude;

[0102] S43: curve fitting is performed on the latitude error to obtain a latitude error fitting target function, and a calculation expression of the latitude error fitting target function is:

[0103]

[0104] wherein, is the latitude error at time t, is the latitude error at time t, is the earth rotation angular velocity in the earth coordinate system, is the sampling time interval, is a first coefficient of the latitude error, is a second coefficient of the latitude error, is a third coefficient of the latitude error, is a fourth coefficient of the latitude error, is a fifth coefficient of the latitude error, is a sixth coefficient of the latitude error, is a seventh coefficient of the latitude error.

[0105] S44: coefficients of the latitude error fitting target function are solved to obtain an estimated value of the gyro drift error in the x direction and an estimated value of the gyro drift error in the y direction;

[0106] The latitude error fitting target function is solved by the least square method, and according to the latitude error and the longitude error sequence obtained by the inverse sequence navigation, a matrix form can be constructed as follows:

[0107]

[0108] wherein, is the latitude error at time t, is the latitude error at time t, is the latitude error at time t, is the latitude error at time t;

[0109] which is expressed as a matrix form is:

[0110]

[0111] wherein, is a coefficient matrix, is a coefficient column vector to be estimated, is a constant vector;

[0112] By using the least squares method, the coefficients to be estimated can be obtained:

[0113]

[0114] The obtained coefficients The gyroscope drift error estimate in the y-direction , The estimated value of the gyroscope drift error in the x-direction ;

[0115] 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:

[0116]

[0117] 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.

[0118] 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;

[0119] 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.

[0120] Compensation is provided for gyroscope drift based on gyroscope drift error.

[0121] 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:

[0122]

[0123] in, for The x-axis misalignment angle of the time platform for the platform x-axis misalignment angle at the initial time, is the platform y-axis misalignment angle at the initial time, is the platform y-axis misalignment angle at the initial time, is is is is is is is is is

[0124] S5: based on the compensated platform misalignment angle and the gyro drift, navigation calculation is performed from the navigation time, and a navigation result is output.

[0125] By performing reverse navigation calculation based on the parameters obtained in the alignment time and the data recorded in the alignment stage after the alignment time ends, and based on the calculation result, the calculation and compensation of the gyro drift estimation error after the alignment stage are realized, and the alignment accuracy of the inertial navigation system is improved.

[0126] As Figure 2 shown, an inertial navigation error correction system based on reverse navigation calculation is used to perform the above-mentioned inertial navigation error correction method based on reverse navigation calculation, comprising:

[0127] The first recording module 101 records the original data measured by the inertial navigation system from the start to the end of the alignment and the transition to the navigation time;

[0128] The second recording module 102 records the gyro drift and the platform initial misalignment angle estimated by the alignment filter at the end of the alignment stage and the transition to the navigation time;

[0129] The reverse calculation module 103 performs navigation calculation on the original data based on time in reverse based on the gyro drift and the platform initial misalignment angle, and obtains a reverse navigation result;

[0130] The error estimation and compensation module 104 estimates the gyro drift error according to the reverse navigation result, and performs secondary compensation on the gyro drift and the platform initial misalignment angle error;

[0131] The navigation calculation module 105 performs navigation calculation based on the compensated platform misalignment angle and the gyro drift from the navigation time, and outputs a navigation result.

[0132] Through the cooperative work of the above-mentioned modules, the secondary estimation and compensation of the drift error are realized by the secondary utilization of the acceleration measured after the start of the inertial navigation system and the misalignment angle and the initial value of the gyro drift estimated by the system at the navigation time, and the navigation precision of the inertial navigation system can be effectively improved; the original inertial data measured from the start of the system to the start of the navigation is relied on in the application, and no additional observation or extended start time is added, the estimation precision of the misalignment angle and the gyro drift of the inertial navigation system can be greatly optimized, the algorithm is simple and reliable, and the high-precision navigation demand can be met.

[0133] The compensation method provided by the application can be popularized to various types of inertial navigation systems and is applicable to static alignment and dynamic alignment processes, and has good popularization applicability.

[0134] Figure 3 An example of a block diagram of an electronic device is shown as Figure 3 As shown, the electronic device can include a processor 201, a communications interface 203, a memory 204 and a communications bus 202, wherein the processor 201, the communications interface 203 and the memory 204 complete mutual communication through the communications bus 202. The processor 201 can call the logic instructions in the memory 204 to execute an inertial navigation error correction method based on reverse sequence navigation solution.

[0135] In addition, the logic instructions in the memory 204 described above can be realized in the form of a software function unit and sold or used as an independent product, and can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product, and the computer software product stored in a storage medium includes a plurality of instructions for causing a computer device (which can be a personal computer, a server or a network device, etc.) to execute all or part of the steps of the method described in the embodiments of the application. The foregoing storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk and various program code storage media.

[0136] On the other hand, the application also provides a computer program product, which includes a computer program stored on a non-transitory computer readable storage medium, and the computer program includes program instructions, when the program instructions are executed by a computer, the computer can execute an inertial navigation error correction method based on reverse sequence navigation solution provided by the above-mentioned methods.

[0137] In yet another aspect, the present application also provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the above-mentioned method for correcting inertial navigation error based on inverse sequence navigation solution.

[0138] The device embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, i.e., can be located in one place or distributed on multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiment scheme according to actual needs. Those skilled in the art can understand and implement without creative labor.

[0139] From the above description of the embodiments, those skilled in the art can clearly understand that the embodiments can be realized by means of software plus necessary general hardware platforms, and of course can also be realized by hardware. Based on such understanding, the above technical solutions can be embodied in the form of software products, and the computer software products can be stored in a computer readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and include a plurality of instructions for making a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods described in each embodiment or some parts of the embodiments.

[0140] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

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; 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. 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 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.

4. The inertial navigation error correction method based on reverse navigation calculation according to claim 3, 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.

5. The inertial navigation error correction method based on reverse navigation calculation according to claim 3, 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. This is 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.

6. The inertial navigation error correction method based on reverse navigation solution according to claim 3, 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.

7. The inertial navigation error correction method based on reverse navigation calculation 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.

8. 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 7, 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.

9. 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 7.

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