A method for processing GNSS / INS integrated data and an integrated navigation system

Abstract

The application relates to the navigation field and provides a method for processing GNSS / INS combined data and a combined navigation system, which comprises receiving data, data preprocessing, initial alignment judgment, data solving and optimization and promotion processing. The method for processing GNSS / INS combined data in the application needs to autonomously judge whether the combined navigation system has completed initial alignment, so that automatic alignment of the combined navigation system is realized, then the processed GNSS / INS combined data which has completed initial alignment is solved and processed and is subjected to optimization and promotion processing, the optimization and promotion processing is fully utilized according to the post-event characteristics, the success of alignment is ensured, and the use experience of navigation is improved.

Description

Technical Field

[0001] This invention relates to the field of navigation, and more particularly to a method and integrated navigation system for processing GNSS / INS combined data. Background Technology

[0002] GNSS (Global Navigation Satellite System) / INS (Inertial Navigation System) integrated navigation systems can provide high-precision positioning, attitude determination, and velocity measurement services, and are a relatively mature technology. By making good use of the combined characteristics of GNSS / INS and their post-event features, high-precision positioning can be achieved in all weather conditions and complex environments.

[0003] Existing technologies for processing GNSS / INS combined data typically suffer from the following problems: First, GNSS / INS combined systems require alignment before startup. Therefore, most existing technologies have stringent requirements for data acquisition during the alignment phase. Lack of strict standards often leads to alignment failure, preventing entry into navigation mode, or resulting in incorrect estimations after entering navigation with an incorrect attitude. For example, with UAVs, if static alignment is not performed during the initial alignment phase, or if dynamic alignment is performed when the forward direction is inconsistent with the inertial navigation northward direction, an incorrect initial attitude or alignment failure will result. Second, the "post-processing" characteristics are not fully utilized for data processing, ultimately impacting the user experience of navigation. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, one of the objectives of the present invention is to provide a method for processing GNSS / INS combined data, which can solve the problems in the prior art of easy alignment failure and failure to make full use of the "post-processing" characteristics of data processing during the processing of GNSS / INS combined data, ultimately affecting the user experience of navigation.

[0005] The second objective of this invention is to provide a combined navigation system for processing GNSS / INS combined data, which can solve the problems in the prior art where alignment is prone to failure and the data processing does not make full use of the "post-processing" characteristics, ultimately affecting the user experience of navigation.

[0006] One of the objectives of this invention is achieved through the following technical solution:

[0007] A method for processing combined GNSS / INS data includes the following steps:

[0008] Receive data, receive raw GNSS / INS combined data;

[0009] Data preprocessing: The original GNSS / INS combined data is preprocessed to obtain processed GNSS / INS combined data;

[0010] Initial alignment determination: Determine whether the processed GNSS / INS combined data has been initially aligned. If yes, execute the data processing step. If no, perform initial alignment using the processed GNSS / INS combined data and then execute the data processing step.

[0011] Data processing involves processing the already processed GNSS / INS combined data to obtain the processing results.

[0012] The optimization and enhancement process is applied to the solution results, and the final accuracy information is output.

[0013] Furthermore, the raw GNSS / INS combined data includes GNSS data and INS data, and the data preprocessing includes:

[0014] INS data preprocessing involves reading the INS data, identifying the inertial navigation type and data frequency in the INS data, judging the time interval of the INS data, detecting whether there is data loss, and determining whether the INS data needs data interpolation to achieve synchronization with the GNSS data.

[0015] GNSS data preprocessing involves reading the GNSS data, performing gross error checks on the satellite measurements corresponding to the GNSS data, and using inertial navigation to assist in cycle slip detection and repair of the GNSS data.

[0016] Furthermore, initial alignment using the processed GNSS / INS combined data includes:

[0017] The carrier type and inertial navigation type corresponding to the original GNSS / INS combined data are detected. If the carrier type is handheld mode or the inertial navigation type is low-precision inertial navigation, the first initial alignment scheme is executed. If the inertial navigation type is high-precision inertial navigation and the carrier type is not handheld mode, the second initial alignment scheme is executed.

[0018] The first initial alignment scheme includes: selecting a large misalignment angle dynamic alignment method to perform initial alignment of the integrated navigation system;

[0019] The second initial alignment scheme includes:

[0020] The motion state of the target object is detected in real time. If the object is completely stationary, the analytical coarse alignment method is used to perform initial alignment of the integrated navigation system.

[0021] If the object is in a shaking state, the shaking base alignment method is used to perform initial alignment of the integrated navigation system.

[0022] If the object is in motion, the ground speed-assisted alignment method is used to perform initial alignment of the integrated navigation system.

[0023] Furthermore, the real-time detection of the target object's motion state includes:

[0024] The base is aligned by shaking according to the INS data in the processed GNSS / INS combined data corresponding to the preset time period, and the approximate attitude of the preset time period is obtained.

[0025] Calculate the difference between the measured value of the accelerator and the local gravity, and the difference between the measured value of the gyroscope and the Earth's rotation speed within the preset time period, and classify the magnitude of the difference into three levels: completely still, shaking, and moving;

[0026] Calculate the standard deviation of the measured values ​​of the accelerator and the gyroscope within the preset time period, and classify the standard deviation into three levels: completely still, jittering, and moving.

[0027] The percentage of the corresponding levels of the difference within the preset time period is statistically analyzed, and the motion state of the object is obtained based on the level corresponding to the standard deviation and the percentage of the corresponding levels of the difference.

[0028] Furthermore, the data processing includes:

[0029] The processed GNSS / INS combined data is processed according to the preset processing mode specified by the target user to obtain the processing result. The preset processing mode is one of the following: DGNSS processing mode, DGNSS / INS loose combination processing mode, DGNSS / INS tight combination processing mode, and DGNSS / INS semi-tight combination processing mode.

[0030] Furthermore, the optimization and improvement process includes:

[0031] The solution results are sequentially processed by RTS smoothing, bidirectional combination processing, and multi-channel processing to obtain the final accuracy information and output it.

[0032] Furthermore, the final accuracy information includes an accuracy time series diagram, an estimation result time series diagram, forward and reverse error diagrams, a multi-channel error diagram, a GNSS error diagram, and an INS error diagram.

[0033] The second objective of this invention is achieved by the following technical solution:

[0034] A combined navigation system for processing GNSS / INS combined data includes a data preprocessing module, an initial alignment module, a judgment module, a solution module, a post-processing module, and an accuracy output module.

[0035] The data preprocessing module receives raw GNSS / INS combined data and performs data preprocessing on the raw GNSS / INS combined data to obtain processed GNSS / INS combined data;

[0036] The judgment module determines whether the integrated navigation system has completed the initial alignment. If so, it sends the processed GNSS / INS combined data to the calculation module; otherwise, it sends the processed GNSS / INS combined data to the initial alignment module.

[0037] The initial alignment module performs initial alignment using the processed GNSS / INS combined data;

[0038] After the integrated navigation system has completed the initial alignment, the calculation module performs calculation on the processed GNSS / INS combined data to obtain the calculation result.

[0039] The post-processing module is used to optimize and improve the solution result to obtain the final accuracy information, and send the final accuracy information to the accuracy output module, which outputs the final accuracy information.

[0040] Furthermore, it also includes a system setting module, which is used to set the alignment mode of the initial alignment module and receive error information sent by the initial alignment module. The system setting module sends the error information to the calculation module for calculation processing of the processed GNSS / INS combined data that has completed the initial alignment.

[0041] Furthermore, it also includes a state detection module, which is used to detect the motion state of the target object in real time and send the motion state to the initial alignment module and the solution module.

[0042] Compared with the prior art, the beneficial effects of the present invention are as follows: The method for processing GNSS / INS combined data in this application needs to autonomously determine whether the combined navigation system has completed initial alignment. By comprehensively considering the inertial navigation type, carrier type, and carrier motion mode, the most suitable initial alignment scheme is automatically selected, thereby realizing the automatic alignment of the combined navigation system. Then, the processed GNSS / INS combined data that has completed initial alignment is solved and optimized. The post-processing characteristics are fully utilized for optimization, ensuring the success of alignment and thus improving the user experience of navigation.

[0043] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Specific embodiments of the present invention are given in detail below with reference to the accompanying drawings. Attached Figure Description

[0044] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0045] Figure 1 This is a flowchart illustrating a method for processing GNSS / INS combined data according to the present invention.

[0046] Figure 2 This is a schematic diagram of the data flow of a combined navigation system for processing GNSS / INS combined data according to the present invention. Detailed Implementation

[0047] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0048] like Figure 1 As shown, a method for processing GNSS / INS combined data according to this application includes the following steps:

[0049] Receive data, specifically raw GNSS / INS combined data. In this embodiment, the raw GNSS / INS combined data includes GNSS data and INS data. The GNSS data is data transmitted by the Global Navigation Satellite System; the INS data is data transmitted by the Inertial Navigation System.

[0050] Data preprocessing involves preprocessing the raw GNSS / INS combined data to obtain processed GNSS / INS combined data. Specifically, this includes:

[0051] INS data preprocessing involves reading INS data, identifying the inertial navigation type and data frequency in the INS data, judging the time interval of the INS data, detecting whether there is data loss, and determining whether the INS data needs data interpolation to achieve synchronization with GNSS data.

[0052] GNSS data preprocessing involves reading GNSS data, performing gross error checks on the satellite measurements corresponding to the GNSS data, and using inertial navigation to assist in cycle slip detection and repair of GNSS data.

[0053] The initial alignment check determines whether the integrated navigation system has completed initial alignment. If so, the data processing step is executed; otherwise, initial alignment is performed using the processed GNSS / INS combined data before executing the data processing step. In this embodiment, initial alignment using the processed GNSS / INS combined data specifically involves: first, setting the carrier type and inertial navigation type. In this embodiment, the carrier type is handheld mode, vehicle-mounted mode, or UAV mode, and the inertial navigation type is low-precision inertial navigation or high-precision inertial navigation. Then, the carrier type and inertial navigation type corresponding to the original GNSS / INS combined data are detected. If the carrier type is handheld mode or the inertial navigation type is low-precision inertial navigation, a first initial alignment scheme is executed. If the inertial navigation type is high-precision inertial navigation and the carrier type is not handheld mode, a second initial alignment scheme is executed. The first initial alignment scheme includes: selecting a large misalignment angle dynamic alignment method to perform initial alignment of the integrated navigation system. The second initial alignment scheme includes: detecting the motion state of the target object in real time. If the object's motion state is completely stationary, an analytical coarse alignment method is used to perform initial alignment of the integrated navigation system. If the object's motion state is jittery, a shaking base alignment method is used to perform initial alignment of the integrated navigation system. If the object's motion state is in motion, a ground speed-assisted alignment method is used to perform initial alignment of the integrated navigation system. Upon completion of the initial alignment, a qualified initial attitude can be obtained, and the error information of the inertial navigation system can be roughly calibrated. This error information is used in subsequent calculation steps. The following explanations are provided regarding the selection of the above alignment modes: (1) For low-precision inertial navigation systems (INS), since they cannot be sensitive to the Earth's rotation, the initial attitude can only be obtained through dynamic alignment. The large misalignment angle mode does not require INS accuracy and can effectively help the INS obtain the initial attitude and roughly calibrate the INS error. At the same time, the large misalignment angle mode does not concern itself with whether the forward direction is consistent with the INS direction, and is also very suitable for handheld mode. (2) When the conditions of high INS accuracy, sufficient static time, and small interference are met, static analytical alignment can achieve better results. (3) When the INS is jittering, shaking the base alignment can achieve better results. (4) When the carrier speed is sufficient, the proportion of GNSS speed error to speed decreases, and the obtained ground heading accuracy is higher. At this time, ground speed is used to assist alignment. In this embodiment, after initial alignment, if the obtained initial attitude is only a usable state, afterward multi-channel smoothing, that is, repeated filtering, and further convergence through forward and reverse state transmission, a high-precision initial attitude at the beginning time can be obtained.

[0054] Preferably, real-time detection of the target object's motion state includes:

[0055] According to the preset time period, the base is shaken and aligned with the INS data in the processed GNSS / INS combined data to obtain the approximate attitude for the preset time period.

[0056] Calculate the difference between the measured value of the accelerator and the local gravity, and the difference between the measured value of the gyroscope and the Earth's rotation speed within a preset time period, and classify the magnitude of the difference into three levels: completely still, shaking, and moving;

[0057] Calculate the standard deviation of the measured values ​​of the accelerator and gyroscope within a preset time period, and categorize the standard deviation into three levels: completely stationary, jittering, and moving. Statistically calculate the percentage of each level corresponding to the difference within the preset time period. Based on the level corresponding to the standard deviation and the percentage of each level, the motion state of the object is obtained. This step specifically involves:

[0058] First, calculate the difference dv between the accelerometer reading and the local gravity, and the difference dw between the gyroscope reading and the Earth's rotation speed for each epoch within the preset time period. Based on inertial navigation accuracy information and the 3 sigma principle, set thresholds for two different differences corresponding to complete stillness θ1 and jitter θ2, representing two states. For complete stillness, the following conditions must be met simultaneously: and During shaking, the following conditions should be met simultaneously: and If either of the above two state judgments fails, the epoch is judged as motion and exits, without proceeding to the next step of standard deviation calculation.

[0059] Next, the standard deviations of the acceleration measurement (stdv) and gyroscope measurement (stdw) for each epoch within the preset time period are calculated. Based on the inertial navigation accuracy information and the 3 Sigma principle, thresholds are set for the two standard deviations corresponding to the two states: complete stillness (λ1), jitter (λ2), and [other conditions]. For complete stillness, the following conditions must be met simultaneously: and During shaking, the following conditions should be met simultaneously: and If either of the above two state judgments fails, the epoch is judged as motion.

[0060] The proportion of epochs in which an object is in motion within a preset time period is calculated to the total number of epochs. The object's motion state within the preset time period is then determined based on set threshold conditions. For example, the condition for motion is that the proportion of motion epochs should be greater than 0.1; the condition for jitter is that the combined proportion of motion and jitter should be greater than 0.3; and the condition for stillness is that the combined proportion of stillness should be greater than 0.7. Assuming there are twenty epochs in total, if seven epochs are judged as motion epochs, the proportion of motion epochs is 0.3, which is greater than the threshold of 0.1 for motion epochs. Therefore, the object is in motion epochs during this time period. If one epoch is judged as motion epochs and ten epochs are jitter epochs, the proportion of motion epochs is less than 0.3, and this time period is not considered a motion epoch. If the combined proportion of motion and jitter is greater than 0.3, this time period is considered a jitter epoch.

[0061] Data processing involves resolving the processed GNSS / INS combined data to obtain the solution results. In this embodiment, four solution modes are provided for the target user to choose from: DGNSS (Differential Global Navigation Satellite System, a type of GNSS positioning) solution mode, DGNSS / INS loose combination solution mode, DGNSS / INS tight combination solution mode, and DGNSS / INS semi-tight combination solution mode. Then, according to the preset solution mode specified by the target user, the processed GNSS / INS combined data that has completed initial alignment is processed to obtain the solution results. In addition, during the solution process, GNSS solution is used to continuously detect the attitude, velocity, and position of the inertial navigation system (INS). This includes using the heading towards the ground to detect the correctness of the object's attitude during high-speed movement; using GNSS velocity to detect the correctness of the INS velocity at high speed; and using GNSS position to verify the INS position when observation conditions are good. If any abnormalities are detected, they are corrected or reset in a timely manner. During data processing, it is also necessary to detect the motion state of the object. Under specific motion states, motion constraints can be used to improve estimation accuracy, such as zero velocity constraints, zero angular velocity constraints, and incompleteness constraints. The second part is the anomaly detection of the inertial navigation system by GNSS. In the solution stage, at each observation epoch, the estimation result of an independent GNSS filter can be used as a verification standard for the mechanical arrangement of the inertial navigation system to determine whether the inertial navigation state is within a reasonable range. In this embodiment, the user can set the solution parameters independently. The user sets the solution parameters according to their needs through the parameter setting interface on the system setting module. The solution parameters include not only the above-mentioned solution mode, but also the initial system state, inertial navigation noise model, and carrier motion model. If the user does not specify the above parameters, the system setting module will use the default parameters or automatically identify and set them. The aforementioned automatic identification is as follows: after the initial alignment of the integrated navigation system is completed, the initial alignment module can calibrate the system error of the integrated navigation system. At this time, the integrated navigation system automatically identifies the inertial navigation type, data frequency, and the aforementioned system error obtained during data preprocessing. The inertial navigation type, data frequency, and system error are the automatically identified solution parameters.

[0062] The optimization and enhancement process involves processing the solution results to improve their accuracy, ultimately outputting the final precision information. Specifically, the solution results are sequentially processed using RTS smoothing, bidirectional combined smoothing, and multi-channel smoothing to obtain and output the final precision information. RTS smoothing, short for Rauch-Tung-Striebel smoother, is a smoothing algorithm that utilizes epoch-time constraint information to recursively improve attitude and velocity accuracy. Bidirectional combined smoothing is a weighted combination of forward and backward solutions, essentially using future observations to constrain the current moment, significantly improving position accuracy. The combination of RTS and bidirectional combined smoothing algorithms can significantly improve attitude, velocity, and position accuracy. The aforementioned final precision information includes, but is not limited to, precision time series plots, estimation result time series plots, forward and reverse error plots, multi-channel error plots, GNSS error plots, and INS error plots.

[0063] like Figure 2As shown, the present invention also provides a combined navigation system for processing GNSS / INS combined data, including a system setting module, a status detection module, a data preprocessing module, an initial alignment module, a judgment module, a calculation module, a post-processing module, and an accuracy output module. The data preprocessing module receives the raw GNSS / INS combined data and performs data preprocessing on the raw GNSS / INS combined data to obtain processed GNSS / INS combined data. The judgment module determines whether the combined navigation system has completed initial alignment. If so, it sends the processed GNSS / INS combined data to the calculation module; otherwise, it sends the processed GNSS / INS combined data to the initial alignment module. The initial alignment module utilizes the processed GNSS / INS combined data... The system performs initial alignment of the integrated navigation system; the calculation module processes the processed GNSS / INS combined data that has completed initial alignment to obtain the calculation result; the post-processing module optimizes and improves the calculation result to obtain the final accuracy information, and sends the final accuracy information to the accuracy output module, which outputs the final accuracy information; the system setting module sets the alignment mode for the initial alignment module and receives the error information sent by the initial alignment module, and sends the error information to the calculation module for processing the processed GNSS / INS combined data that has completed initial alignment; the state detection module detects the motion state of the target object in real time and sends the object motion state to the initial alignment module and the calculation module. In this embodiment, the system setting module is also used to provide users with the function of setting solution parameters. Users can set the solution parameters they need through the system setting module. The solution parameters include not only the solution mode mentioned above, but also the initial system state, inertial navigation noise model, and carrier motion model. If the user does not specify the above parameters, the system setting module will use the default parameters or automatically identify and set them. The aforementioned automatic identification is specifically as follows: after the initial alignment of the integrated navigation system is completed, the initial alignment module can calibrate the system error of the integrated navigation system. At this time, the integrated navigation system automatically identifies the inertial navigation type, data frequency, and the aforementioned system error obtained during the data preprocessing. The inertial navigation type, data frequency, and system error are the automatically identified solution parameters.

[0064] This invention provides a method for processing GNSS / INS combined data. It autonomously determines whether the integrated navigation system has completed initial alignment. By comprehensively considering the inertial navigation type, carrier type, and carrier motion mode, it automatically selects the most suitable initial alignment scheme, thereby achieving automated alignment of the integrated navigation system. It then processes and optimizes the pre-aligned GNSS / INS combined data, fully utilizing post-alignment characteristics for optimization, ensuring alignment success and improving the user experience. Automatic detection throughout the initial alignment process, coupled with continuous state monitoring and post-alignment multi-channel smoothing, ensures the system enters the navigation phase with the correct attitude. Post-alignment bidirectional combination and RTS smoothing guarantee high accuracy of the results.

[0065] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Those skilled in the art can readily implement the present invention based on the accompanying drawings and the description above. However, any modifications, alterations, or variations made by those skilled in the art without departing from the scope of the present invention, utilizing the disclosed technical content, are equivalent embodiments of the present invention. Furthermore, any equivalent changes, alterations, or variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. A method for processing GNSS / INS combined data, characterized in that, Includes the following steps: Receive data, receive raw GNSS / INS combined data; Data preprocessing: The original GNSS / INS combined data is preprocessed to obtain processed GNSS / INS combined data; Initial alignment judgment: Determine whether the integrated navigation system has completed initial alignment. If yes, execute the data processing step. If no, perform initial alignment using the processed GNSS / INS combined data and then execute the data processing step. The carrier type and inertial navigation type corresponding to the original GNSS / INS combined data are detected. If the carrier type is handheld mode or the inertial navigation type is low-precision inertial navigation, the first initial alignment scheme is executed. If the inertial navigation type is high-precision inertial navigation and the carrier type is not handheld mode, the second initial alignment scheme is executed. The first initial alignment scheme includes: selecting a large misalignment angle dynamic alignment method combined with a navigation system for initial alignment; The second initial alignment scheme includes: real-time detection of the target object's motion state; if the object is completely stationary, a coarse analytical alignment method is used to perform initial alignment of the integrated navigation system; if the object is jittering, a wobbling base alignment method is used to perform initial alignment of the integrated navigation system; if the object is in motion, a ground speed-assisted alignment method is used to perform initial alignment of the integrated navigation system. The real-time detection of the target object's motion state includes: aligning the swaying base according to the INS data in the processed GNSS / INS combined data corresponding to a preset time period to obtain a rough attitude for that time period; calculating the difference between the accelerator measurement value and the local gravity, and the difference between the gyroscope measurement value and the Earth's rotation speed within the preset time period, classifying the difference into three levels: completely stationary, jittering, and moving; calculating the standard deviation of the accelerator and gyroscope measurement values ​​within the preset time period, classifying the standard deviation into three levels: completely stationary, jittering, and moving; statistically analyzing the proportion of each level corresponding to the difference within the preset time period, and obtaining the object's motion state based on the level corresponding to the standard deviation and the proportion of each level corresponding to the difference. Data processing involves processing the already processed GNSS / INS combined data to obtain the processing results. The optimization and enhancement process is applied to the solution results, and the final accuracy information is output.

2. The method for processing GNSS / INS combined data as described in claim 1, characterized in that, The raw GNSS / INS combined data includes GNSS data and INS data, and the data preprocessing includes: INS data preprocessing involves reading the INS data, identifying the inertial navigation type and data frequency in the INS data, judging the time interval of the INS data, detecting whether there is data loss, and determining whether the INS data needs data interpolation to achieve synchronization with the GNSS data. GNSS data preprocessing involves reading the GNSS data, performing gross error checks on the satellite measurements corresponding to the GNSS data, and using inertial navigation to assist in cycle slip detection and repair of the GNSS data.

3. The method for processing GNSS / INS combined data as described in claim 1, characterized in that, The data processing includes: The processed GNSS / INS combined data is processed according to the preset processing mode specified by the target user to obtain the processing result. The preset processing mode is one of the following: DGNSS processing mode, DGNSS / INS loose combination processing mode, DGNSS / INS tight combination processing mode, and DGNSS / INS semi-tight combination processing mode.

4. The method for processing GNSS / INS combined data as described in claim 1, characterized in that, The optimization and improvement process includes: The solution results are sequentially processed by RTS smoothing, bidirectional combination processing, and multi-channel processing to obtain the final accuracy information and output it.

5. A method for processing GNSS / INS combined data as described in claim 4, characterized in that, The final accuracy information includes an accuracy time series diagram, an estimation result time series diagram, forward and reverse error diagrams, a multi-channel error diagram, a GNSS error diagram, and an INS error diagram.

6. A combined navigation system for processing GNSS / INS combined data, characterized in that, It includes a data preprocessing module, an initial alignment module, a judgment module, a solution module, a post-processing module, and an accuracy output module. The data preprocessing module receives raw GNSS / INS combined data and performs data preprocessing on the raw GNSS / INS combined data to obtain processed GNSS / INS combined data; The judgment module determines whether the integrated navigation system has completed the initial alignment. If so, it sends the processed GNSS / INS combined data to the calculation module; otherwise, it sends the processed GNSS / INS combined data to the initial alignment module. The initial alignment module performs initial alignment using the processed GNSS / INS combined data; it detects the carrier type and inertial navigation type corresponding to the original GNSS / INS combined data; if the carrier type is handheld mode or the inertial navigation type is low-precision inertial navigation, it executes the first initial alignment scheme; if the inertial navigation type is high-precision inertial navigation and the carrier type is not handheld mode, it executes the second initial alignment scheme. The first initial alignment scheme includes: selecting a large misalignment angle dynamic alignment method combined with a navigation system for initial alignment; The second initial alignment scheme includes: real-time detection of the target object's motion state; if the object is completely stationary, a coarse analytical alignment method is used to perform initial alignment of the integrated navigation system; if the object is jittering, a wobbling base alignment method is used to perform initial alignment of the integrated navigation system; if the object is in motion, a ground speed-assisted alignment method is used to perform initial alignment of the integrated navigation system. The real-time detection of the target object's motion state includes: aligning the swaying base according to the INS data in the processed GNSS / INS combined data corresponding to a preset time period to obtain a rough attitude for that time period; calculating the difference between the accelerator measurement value and the local gravity, and the difference between the gyroscope measurement value and the Earth's rotation speed within the preset time period, classifying the difference into three levels: completely stationary, jittering, and moving; calculating the standard deviation of the accelerator and gyroscope measurement values ​​within the preset time period, classifying the standard deviation into three levels: completely stationary, jittering, and moving; statistically analyzing the proportion of each level corresponding to the difference within the preset time period, and obtaining the object's motion state based on the level corresponding to the standard deviation and the proportion of each level corresponding to the difference. After the integrated navigation system has completed the initial alignment, the calculation module performs calculation on the processed GNSS / INS combined data to obtain the calculation result. The post-processing module is used to optimize and improve the solution result to obtain the final accuracy information, and send the final accuracy information to the accuracy output module, which outputs the final accuracy information.

7. A combined navigation system for processing GNSS / INS combined data as described in claim 6, characterized in that, It also includes a system setting module, which is used to set the alignment mode of the initial alignment module and receive error information sent by the initial alignment module. The system setting module sends the error information to the calculation module for calculation processing of the processed GNSS / INS combined data that has completed the initial alignment.

8. A combined navigation system for processing GNSS / INS combined data as described in claim 6, characterized in that, It also includes a state detection module, which is used to detect the motion state of the target object in real time and send the motion state to the initial alignment module and the solution module.

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