Satellite information source optimal point correction positioning method, device, equipment and storage medium

Abstract

The invention relates to a satellite information source optimal point correction positioning method and device, equipment and a storage medium. The method comprises the following steps: acquiring a gyroscopic drift estimation model of a sky-direction gyroscope, and constructing an optimization model by maximizing a denominator term of the gyroscopic drift estimation model so as to minimize a gyroscopic drift rounding error; solving the optimization model according to the earth rotation angular velocity and the Schula frequency of the inertial navigation system to obtain a maximum value point of a function corresponding to a denominator term; an initial value point set is obtained according to maximum value points in two earth periods before the voyage, accurate values of initial value points close to a single-point correction time period in the initial value point set are solved by adopting a Newton iteration method, and accurate maximum value points in the single-point correction time period are calculated according to the accurate values and the period of a first-order derivative function of a denominator term. Taking the accurate maximum value point as an optimal gyroscope correction point; and carrying out single-point correction by utilizing the optimal gyroscope correction point. By adopting the method, the navigation precision of the rotation modulation inertial navigation system can be improved.

Description

Technical Field

[0001] This application relates to the field of inertial navigation technology, and particularly to a method, device, equipment, and storage medium for correcting and positioning the optimal point of a satellite signal source. Background Art

[0002] With the development of inertial navigation technology, the rotation modulation inertial navigation technology has emerged. The rotation modulation inertial navigation periodically changes the sensitive axis direction of inertial devices, evenly modulating the errors of inertial devices to 0 within a certain period, which can effectively reduce the influence of errors on navigation accuracy, especially showing significant advantages in improving the navigation accuracy during long-term operation.

[0003] In a rotation modulation inertial navigation system, the drift of the vertical gyro is the main error source. The drift of the vertical gyro refers to the non-ideal rotation phenomenon of the gyro along the vertical axis direction. Due to the existence of disturbing torques, it is divided into two categories: systematic and random. Although its numerical magnitude is very small, due to the limited ability of rotation modulation to suppress it, the errors will accumulate continuously, thus having a significant impact on the navigation accuracy during long-term operation, such as causing the longitude error to slowly diverge over time.

[0004] Currently, for the processing of the drift of the vertical gyro, the traditional method is to obtain its approximate value through long-term filtering estimation. This method requires long-term collection of longitude and latitude observation values, using filtering algorithms to remove noise interference and extract the drift information of the vertical gyro. However, in practical applications, affected by factors such as task time limitations and changes in observation conditions (such as signal occlusion, equipment failures, etc.), it is difficult to continuously and stably obtain long-term longitude and latitude observation values. This makes the traditional method inefficient, unable to meet the actual needs, and difficult to accurately estimate the drift amount of the vertical gyro, thereby affecting the navigation accuracy of the rotation modulation inertial navigation system. Summary of the Invention

[0005] Based on this, it is necessary to provide a method, device, equipment, and storage medium for correcting and positioning the optimal point of a satellite signal source to address the above technical problems.

[0006] A method for correcting and positioning the optimal point of a satellite signal source, the method comprising: Obtain a gyro drift estimation model of a vertical gyroscope, and construct an optimization model by maximizing the denominator term of the gyro drift estimation model to minimize the gyro drift rounding error; Solve the optimization model according to the angular velocity of the Earth's rotation and the Schuler frequency of the inertial navigation system to obtain the maximum point of the function corresponding to the denominator term; An initial value point set is obtained based on the maximum value points within the first two Earth cycles of the voyage. The Newton iteration method is used to solve for the exact value of the initial value point in the initial value point set that is close to the single-point calibration time period. Based on the exact value and the period of the first derivative function of the denominator term, the exact maximum value point within the single-point calibration time period is calculated, and the exact maximum value point is used as the optimal gyro calibration point; Single-point calibration is performed using the optimal gyro calibration point to obtain calibrated navigation and positioning data.

[0007] In one embodiment, solving for the maximum value point of the function corresponding to the denominator term by solving the optimization model according to the Earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system includes: calculating the first derivative function of the denominator term of the gyro drift estimation model with respect to time, and substituting the Earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system into the first derivative function; calculating the maximum value point of the function corresponding to the denominator term based on the first derivative function.

[0008] In one embodiment, using the Newton iteration method to solve for the exact value of the initial value point in the initial value point set that is close to the single-point calibration time period includes: obtaining the preset single-point calibration time period; using the initial value point in the initial value point set that is close to the single-point calibration time period as the initial solution, and using the Newton iteration method to iteratively solve the equation when the first derivative function is 0 until the iteration stop condition is met, and then outputting the exact solution.

[0009] In one embodiment, using the optimal gyro calibration point to perform single-point calibration to obtain calibrated navigation and positioning data includes: obtaining the real-time data of the celestial gyro at the optimal gyro calibration point, performing data validity judgment on the real-time data according to the preset data validity criterion. If the real-time data is valid, celestial gyro drift estimation is performed on the real-time data and the positioning error caused is compensated to obtain the output calibrated navigation and positioning data.

[0010] In one embodiment, the method further includes: performing data validity judgment on the real-time data according to the preset data validity criterion. If the real-time data is invalid, position reset is performed using satellite data.

[0011] In one embodiment, the validity criterion includes condition number judgment, latitude and longitude consistency check, and outlier detection.

[0012] In one embodiment, the gyro drift estimation model is: ; where, is the celestial gyro drift, is the latitude change amount, is the latitude, is the angular velocity of the Earth's rotation, is the time, is the change in longitude, is the longitude, is the Schuler frequency of the inertial navigation system.

[0013] A satellite signal source optimal point correction and positioning device, the device includes: An optimization model construction module, used to obtain the gyro drift estimation model of the celestial gyroscope, construct an optimization model by maximizing the denominator term of the gyro drift estimation model to minimize the gyro drift rounding error; An optimization model solving module, used to solve the optimization model according to the angular velocity of the Earth's rotation and the Schuler frequency of the inertial navigation system to obtain the maximum point of the function corresponding to the denominator term; A correction point optimization module, used to obtain an initial value point set according to the maximum points belonging to the first two Earth cycles of the voyage, use the Newton iteration method to solve the exact value of the initial value point in the initial value point set close to the single-point correction time period, calculate the exact maximum point within the single-point correction time period according to the exact value and the period of the first derivative function of the denominator term, and use the exact maximum point as the best gyro correction point; A positioning correction module, used to perform single-point correction using the best gyro correction point to obtain the corrected navigation and positioning data.

[0014] A computer device, including a memory and a processor, the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented: Obtain the gyro drift estimation model of the celestial gyroscope, construct an optimization model by maximizing the denominator term of the gyro drift estimation model to minimize the gyro drift rounding error; Solve the optimization model according to the angular velocity of the Earth's rotation and the Schuler frequency of the inertial navigation system to obtain the maximum point of the function corresponding to the denominator term; Obtain an initial value point set according to the maximum points belonging to the first two Earth cycles of the voyage, use the Newton iteration method to solve the exact value of the initial value point in the initial value point set close to the single-point correction time period, calculate the exact maximum point within the single-point correction time period according to the exact value and the period of the first derivative function of the denominator term, and use the exact maximum point as the best gyro correction point; Perform single-point correction using the best gyro correction point to obtain the corrected navigation and positioning data.

[0015] A computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented: Obtain the gyro drift estimation model of the celestial gyroscope, construct an optimization model by maximizing the denominator term of the gyro drift estimation model to minimize the gyro drift rounding error; Solve the optimization model according to the earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system to obtain the maximum point of the function corresponding to the denominator term; Obtain the set of initial points based on the maximum points within the first two earth periods of the voyage. Use the Newton iteration method to solve the exact value of the initial point in the set of initial points that is close to the single-point calibration time period. Calculate the exact maximum point within the single-point calibration time period according to the exact value and the period of the first derivative function of the denominator term, and use the exact maximum point as the optimal gyro calibration point; Perform single-point calibration using the optimal gyro calibration point to obtain the calibrated navigation and positioning data.

[0016] The above satellite signal source optimal point calibration and positioning method, device, equipment, and storage medium construct an optimization model by maximizing the denominator term of the gyro drift estimation model, which can minimize the gyro drift rounding error from the calculation source, avoid accuracy loss caused by numerical processing, ensure the reliability of the estimated value, solve the optimization model in combination with the earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system, can accurately determine the maximum point of the denominator term function, get rid of the dependence on long-term observation data, select the maximum points within the first two earth periods of the voyage to determine the set of initial points, and use the Newton iteration method to accurately solve, which can quickly locate the optimal gyro calibration point, greatly improve the calibration efficiency, use the optimal gyro calibration point to implement single-point calibration, can effectively suppress the accumulation of celestial gyro drift error, avoid the divergence of longitude error, significantly improve the navigation accuracy of the rotation modulation inertial navigation system, and meet the actual needs of satellite long-term high-precision navigation. Description of the Drawings

[0017] Figure 1 It is a schematic flowchart of the satellite signal source optimal point calibration and positioning method in an embodiment; Figure 2 It is a schematic curve diagram of the first derivative function of the denominator term in an embodiment; Figure 3 It is a schematic curve diagram of the denominator term in an embodiment; Figure 4 It is a schematic flowchart of the positioning and calibration in an embodiment; Figure 5 It is a schematic diagram of the optimal point 1 calibration effect in the satellite signal source optimal point calibration in an embodiment, where Figure 5 (a) is the latitude error schematic diagram of the satellite signal source optimal point 1, Figure 5 (b) is the longitude error schematic diagram of the satellite signal source optimal point 1, Figure 5 (c) is the positioning error schematic diagram of the satellite signal source optimal point 1; Figure 6 Schematic diagram of the point distribution of the gyro drift estimation value in one embodiment; Figure 7 Schematic diagram of the effect of the gyro drift estimation mean point in the first paragraph in one embodiment, where Figure 7 (a) is the latitude error of the GNSS drift estimation mean point 1, Figure 7 (b) is the longitude error of the GNSS drift estimation mean point 1, Figure 7 (c) is the positioning error of the GNSS drift estimation mean point 1; Figure 8 Structural block diagram of the satellite signal source optimal point correction positioning device in one embodiment; Figure 9 Internal structure diagram of a computer device in one embodiment. Detailed implementation manners

[0018] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0019] For rotation modulation inertial navigation, the main error is the drift of the vertical gyro. The numerical magnitude of the vertical gyro drift is very small, and the resulting latitude and longitude errors are not large. The traditional method is to obtain an approximate value through long-term filtering estimation, which requires long-term latitude and longitude observation values and is difficult to meet in practice.

[0020] In one embodiment, as Figure 1 shown, a satellite signal source optimal point correction positioning method is provided, including the following steps: Step 102, obtain the gyro drift estimation model of the vertical gyroscope, and construct an optimization model by maximizing the denominator term of the gyro drift estimation model to minimize the gyro drift rounding error.

[0021] The rounding error is the error generated due to the rounding operation of numbers during the numerical calculation process. In the gyro drift estimation model, when the denominator term takes the maximum value, the denominator term becomes much larger relative to the numerator. The gyro drift estimation model is as follows: .

[0022] At this time, due to the small changes in the numerator and denominator terms caused by factors such as rounding operations, the influence on the entire fraction (i.e., the gyro drift estimation value) will be smaller. Therefore, the estimated gyro drift rounding error is minimized. Based on this, to minimize the rounding error during the estimation process, an optimization model is constructed, and its optimization objective is to maximize the denominator term of the gyro drift estimation model.

[0023] It can be understood that by optimizing the mathematical model, the rounding error is reduced at the calculation source, improving the accuracy of the gyro drift estimation value and providing a more reliable data basis for subsequent positioning correction.

[0024] Step 104: Solve the optimization model according to the angular velocity of the Earth's rotation and the Schuler frequency of the inertial navigation system to obtain the maximum point of the function corresponding to the denominator term.

[0025] By maximizing the denominator, the estimation error caused by finite-precision calculation can be significantly reduced, and the robustness of gyro drift parameter identification can be improved. From the gyro drift estimation model, the maximum value of the denominator can be approximately regarded as the optimal gyro correction point. In step 106, the optimal gyro correction point is further optimized to improve the correction accuracy.

[0026] Step 106: Obtain the set of initial value points based on the maximum points within the first two Earth cycles of the voyage. Use the Newton iteration method to solve the exact value of the initial value point in the set of initial value points that is close to the single-point correction time period. Calculate the exact maximum point within the single-point correction time period according to the exact value and the period of the first derivative function of the denominator term, and use the exact maximum point as the optimal gyro correction point.

[0027] The maximum points within the first two Earth cycles of the voyage contain important information related to the initial operating state of the satellite. Selecting the set of initial value points from them can provide a suitable starting value for subsequent accurate solution. The Newton iteration method is an efficient numerical iteration algorithm used to solve the roots or extrema of a function. By using it to solve the exact value of the initial value point close to the single-point correction time period, and then combining the period of the periodic function to calculate the exact maximum point within the single-point correction time period.

[0028] It can be understood that the determined optimal gyro correction point is obtained by comprehensively considering the characteristics of the initial stage of satellite operation and the requirements of the single-point correction time period. Compared with traditional methods, it does not require long-term waiting for data accumulation to determine the correction point, and can quickly and accurately find the point that is most suitable for gyro correction in the current mission stage, greatly improving the efficiency and accuracy of positioning correction.

[0029] Step 108: Perform single-point correction using the optimal gyro correction point to obtain the corrected navigation and positioning data.

[0030] After determining the optimal gyro correction point, use the data at this point for single-point correction. By correcting the celestial gyro drift, the correction of satellite positioning is finally realized.

[0031] In the above satellite signal source optimal point calibration and positioning method, an optimization model is constructed by maximizing the denominator term of the gyro drift estimation model, which can minimize the gyro drift rounding error from the calculation source, avoid accuracy loss caused by numerical processing, ensure the reliability of the estimated value, solve the optimization model by combining the earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system, accurately determine the maximum point of the denominator term function, get rid of the dependence on long-term observation data, select the maximum points within the first two earth cycles of the voyage to determine the initial value point set, and use the Newton iteration method to accurately solve, which can quickly locate the optimal gyro calibration point, greatly improve the calibration efficiency, use the optimal gyro calibration point to implement single-point calibration, effectively suppress the accumulation of the celestial gyro drift error, avoid the divergence of the longitude error, significantly improve the navigation accuracy of the rotation modulation inertial navigation system, and meet the actual needs of high-precision navigation of the satellite during long-term flight.

[0032] In one embodiment, solving the optimization model according to the earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system to obtain the maximum point of the function corresponding to the denominator term includes: calculating the first-order derivative function of the denominator term of the gyro drift estimation model with respect to time, and substituting the earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system into the first-order derivative function; calculating the maximum point of the function corresponding to the denominator term according to the first-order derivative function.

[0033] In this embodiment, denote the denominator of the gyro drift estimation model as , Derive : ; Let , there is: ; It can be calculated that , let , that is: ; Its curve is as shown in Figure 2 , and the solution of the above formula needs to satisfy at the same time, and this solution can be considered as the maximum point. That is: ; Thus, the set of maximum points of the denominator is obtained.

[0034] In one embodiment, adopting the Newton iteration method to solve the exact value of the initial value point in the initial value point set that is close to the single-point calibration time period includes: obtaining the preset single-point calibration time period; taking the initial value point in the initial value point set that is close to the single-point calibration time period as the initial solution, and using the Newton iteration method to iteratively solve the equation when the first-order derivative function is 0 until the iteration stop condition is met, and then outputting the exact solution.

[0035] In this embodiment, through a series of steps, including obtaining an initial value point set based on the maximum points within the first two Earth cycles of the voyage, using the Newton iteration method to solve the exact value of the initial value point near the single-point correction time period, and then determining the optimal gyro correction point. The optimal correction time can be calculated online, and damping single-point calibration is performed at this time, which can make the correction effect reach the best, effectively reduce the influence of the celestial gyro drift error on the navigation accuracy of the rotation modulation inertial navigation system, and improve the accuracy and reliability of the positioning correction.

[0036] Specifically, the implementation single-point correction time period is 50% to 80% of the voyage, 150 hours to 220 hours. In order to calculate the optimal point of the single-point correction time period in advance, the optimal point is calculated within the first two Earth cycles of the voyage, and the period is approximated as , and the optimal point within 150 hours to 220 hours is deduced.

[0037] The first two Earth cycles of the voyage are 48 hours, and x is converted to 0 to 12.6. According to the curve, 4 initial value points are selected, and 2 minimum value points can be deleted from these four initial points by selecting those that satisfy the second derivative less than 0. Finally, the initial value points are 4.4 and 10.9.

[0038] Since the period is approximated as , the amplitude increases by every other period. The closer the initial value point is to 150 hours to 220 hours, the smaller the error in deducing the optimal point. Take the initial value point . In order to obtain the exact value of the initial value point, the Newton iteration method is used to solve the exact value: ; The solution is , where represents the number of iterations. The optimal points within 150 hours to 220 hours are obtained by adding to x respectively, and the converted times are . For the convenience of description, these three points are called the calculated optimal points 1, 2, and 3.

[0039] In one embodiment, single-point calibration is performed using the optimal gyro correction point, and the corrected navigation and positioning data obtained includes: obtaining the real-time data of the celestial gyroscope at the optimal gyro correction point, performing data validity judgment on the real-time data according to the pre-set data validity criterion, and if the real-time data is valid, estimating the celestial gyro drift and compensating the positioning error caused, to obtain the output corrected navigation and positioning data.

[0040] In this embodiment, traditional filtering estimation requires continuous multi-frame long-time observations to accurately estimate the drift of the celestial gyroscope, while the present invention calculates an approximate value of the celestial gyroscope drift by obtaining an analytical solution. Compared with the traditional method, the calculation time is greatly shortened, and it can quickly complete the calculations related to gyroscope drift under the condition of limited satellite observation data (only the observation at one point and one moment), meeting the requirements for calculation speed in practical applications and improving the system response efficiency.

[0041] As Figure 4 shown in the schematic diagram of the positioning correction process, in the figure, the accelerometer is represented as the accelerometer table, and the gyroscope is represented as the gyroscope. is the external reference position, is the external reference velocity, is the external reference altitude, is the damping horizontal position, is the damping composite position, is the damping velocity, is the damping altitude, is the inertial navigation solution velocity, is the inertial navigation solution position, is the inertial navigation direction cosine matrix, is the positioning error caused by the estimated gyroscope drift calculated after substituting the estimated gyroscope drift into the inertial navigation error calculation model. is the estimated value closer to the true value obtained after deducting the positioning error caused by the estimated gyroscope drift from the inertial navigation positioning output. Specifically, using the optimal gyroscope correction point for damping single-point calibration, after the damping single-point calibration, according to the relevant data and models in the calibration process, the drift error of the celestial gyroscope is estimated, substituted into the inertial navigation error solution model, the positioning error caused by the drift error of the celestial gyroscope is calculated in real time, and output correction is used to compensate the navigation positioning parameters output by the inertial navigation solution to achieve positioning correction.

[0042] In one embodiment, the method further includes: judging the data validity of the real-time data according to the pre-set data validity criterion, and if the real-time data is invalid, using satellite data for position reset.

[0043] In this embodiment, this process reduces the influence of environmental interference on the data, provides a high-quality data basis for subsequent calculations of the theoretical and actual gyroscope drift estimates, and further ensures the accuracy and stability of the single-point calibration.

[0044] In one embodiment, the validity criterion includes condition number judgment, longitude and latitude consistency check, and outlier detection.

[0045] In one embodiment, the gyroscope drift estimation model is: ; Wherein, is the celestial drift of the gyroscope, is the change in latitude, is the latitude, is the angular velocity of the Earth's rotation, is the time, is the change in longitude, is the longitude, is the Schuler frequency of the inertial navigation system.

[0046] As Figure 3 shown by the curve of the denominator y, three maximum points can be selected within the range of 150 hours to 220 hours, and the optimal point obtained according to the drawing is called the actual optimal point. By comparing the specific times of the calculated optimal point and the actual optimal point, it is found that the differences between the two are , and the deviation is about 10 minutes. Taking the satellite navigation as the reference signal, the error statistical effects of the calculated optimal point and the actual optimal point are compared, as shown in Table 1.

[0047] Table 1 Comparison of the effects of the optimal correction points

[0048] It can be seen from Table 1 that the effects of the calculated optimal point and the actual optimal point are consistent. This shows that by using periodicity, the optimal point can be calculated in advance. For the sake of convenience of description, the calculated optimal points 1, 2, and 3 are simply referred to as optimal points 1, 2, and 3.

[0049] It can be understood that in addition to the widely used satellite signal sources, the signal sources used in the method of the present invention can also be semi-submerged buoy signal sources, radio signal sources or underwater acoustic signal sources. The present invention uses the ocean as the test environment, and the entire ocean test mainly includes acoustic positioning, satellite positioning, radio / acoustic positioning, satellite / underwater acoustic and semi-submerged buoy. Five signal sources are used to verify the correction effect at the pre-calculated optimal points. The accuracies of different signal sources are comparable and in the same order of magnitude. The smaller the signal source error, the better the accuracy improvement effect. Only the verification results of the satellite signal source are listed below. If there is no test data for a certain signal source at the optimal point, then satellite data plus noise is used for simulation, and the simulated optimal point is marked with ".

[0050] Based on the pre-calculated optimal points, the satellite signal source is used for verification. Through theoretical calculation, there are three optimal correction points in the time period of 150 hours - 220 hours. The correction effect of the optimal point 1 at the optimal point of the satellite signal source is as Figure 5 shown, where Figure 5 (a) is the schematic diagram of the latitude error of the optimal point 1 of the satellite signal source, Figure 5 (b) is the schematic diagram of the longitude error of the optimal point 1 of the satellite signal source, Figure 5 (c) is the schematic diagram of the positioning error of the optimal point 1 of the satellite signal source. From Figure 5It can be seen that the maximum value of the pure inertial navigation positioning error is 2.0 n mile. After calibration at calibration point 1, the maximum value of the damped inertial navigation positioning error is reduced from 1.71 n mile to 0.97 n mile. The root mean square (RMS) errors after calibration point 1 are calculated for pure inertial navigation, damped inertial navigation, and single-point damped calibration, which are 1.16 n mile, 1.14 n mile, and 0.46 n mile respectively. The statistical characteristics of the errors after calibration point 1 indicate that the accuracy of inertial navigation positioning can be effectively improved by implementing single-point damped calibration. The calibration effects at the second and third calibration points are similar to that at the first calibration point. The statistical results of the errors after calibration points are shown in Table 2: Table 2 Calibration Effect of the Optimal Point of Satellite Signal Source

[0051] The following verifies through measured data that the effect of the optimal point is better than that of other points. Since there are many points other than the optimal point, representative points are selected for comparison. Because the more accurate the gyro drift estimate value is, the better the calibration effect is, so points are selected according to the maximum, minimum, and mean values of the gyro drift estimate. For the satellite signal source, within each time period, points are selected according to the maximum, minimum, and mean values of the gyro drift estimate and compared with the optimal point. The distribution of each point is as Figure 6 shown. The effect of the mean point of the gyro drift estimate in the first segment is as Figure 7 shown. Among them, Figure 7 (a) is the latitude error of the mean point 1 of the satellite navigation drift estimate, Figure 7 (b) is the longitude error of the mean point 1 of the satellite navigation drift estimate, Figure 7 (c) is the positioning error of the mean point 1 of the satellite navigation drift estimate. It can be seen that the calibration effect of the point obtained according to the mean value of the drift estimate of satellite navigation is feasible, and the effects of the second and third segments are similar to that of the first segment. The effects of each point are shown in Table 3, verifying that the calibration effect of the optimal point is better than that of other points.

[0052] Table 3 Comparison of the Effects between the Representative Points of the Satellite Navigation Drift Estimate Value and the Optimal Point

[0053] Due to space limitations, only the satellite signal source is used for illustration. Measured data of different signal sources show that the calibration effect of the optimal point is better than that of other points.

[0054] In a specific embodiment, the single-point calibration algorithm is executed at three locations on the entire track to test the positioning error correction effect. The first single-point calibration is performed using the semi-submersible buoy radio positioning information; the second single-point calibration is performed using the semi-submersible buoy satellite positioning information; for the third point, satellite positioning information is used at the moment 48 hours before the end of the voyage for calibration. The improvement effects of the positioning errors of the three single-point calibrations are shown in Table 4. The positioning errors of the three single-point calibrations are improved by 50.6% compared with damped and pure inertial navigation.

[0055] Comparison of the improvement effects of the positioning errors in three single-point calibrations in Table 4

[0056] The object of the percentage increase in the table is the root mean square of the damped single-point calibration: Relative improvement compared to pure inertial navigation = (root mean square of pure inertial navigation - root mean square of damped single-point calibration) / root mean square of pure inertial navigation × 100%; Relative improvement compared to damping = (root mean square of damping - root mean square of damped single-point calibration) / root mean square of damping × 100%; The method of the present invention greatly improves the calibration efficiency compared with the traditional method. The index that the single-point calibration time is less than 10 seconds is verified. Here, the single-point calibration time can be divided into three parts: 1) Determine whether the moment corresponding to the single-point position signal can be used for calibration. This part takes about 0.1 second; 2) If the moment is available, use the data in the 8 seconds after this moment to judge the data validity, perform a consistency analysis on the 8-second data. If the consistency analysis is satisfied, it is considered that the position signal of this point is valid, and the last 1 second of the 8-second data is taken as the calibration data. This part takes about 8 seconds; 3) If the data meets the consistency requirements, estimate the drift of the vertical gyro according to the single-point position signal, and calculate the time from when the position signal enters the inertial navigation error estimation module to when the estimated value of the vertical gyro drift is calculated. This part takes about 0.2 second.

[0057] The single-point calibration time is the sum of the times of these three parts. The calculation times of the three single-point calibrations during the actual flight are shown in Table 5. The times of the three single-point calibrations are all less than 10 seconds, meeting the technical indicators.

[0058] Table 5 Calibration Time

[0059] It should be understood that although Figure 1 the steps in the flowchart of Figure 1 are shown in sequence according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise clearly stated in this article, the execution of these steps has no strict order restriction, and these steps can be executed in other orders. Moreover,

[0060] In one embodiment, asFigure 8 As shown, a satellite signal source optimal point correction and positioning device is provided, including: An optimization model construction module 802, configured to obtain a gyro drift estimation model of a celestial gyroscope, construct an optimization model by maximizing the denominator term of the gyro drift estimation model, so as to minimize the gyro drift rounding error; An optimization model solving module 804, configured to solve the optimization model according to the earth's angular velocity of rotation and the Schuler frequency of an inertial navigation system, and obtain the maximum point of the function corresponding to the denominator term; A correction point optimization module 806, configured to obtain an initial value point set according to the maximum points belonging to the first two earth cycles of the voyage, use the Newton iteration method to solve the exact value of the initial value point close to the single-point correction time period in the initial value point set, calculate the exact maximum point in the single-point correction time period according to the exact value and the period of the first derivative function of the denominator term, and use the exact maximum point as the optimal gyro correction point; A positioning correction module 808, configured to perform single-point correction using the optimal gyro correction point to obtain corrected navigation and positioning data.

[0061] In one embodiment, solving the optimization model according to the earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system to obtain the maximum point of the function corresponding to the denominator term includes: calculating the first derivative function of the denominator term of the gyro drift estimation model with respect to time, and substituting the earth's angular velocity of rotation and the Schuler frequency of the inertial navigation system into the first derivative function; calculating the maximum point of the function corresponding to the denominator term according to the first derivative function.

[0062] In one embodiment, using the Newton iteration method to solve the exact value of the initial value point close to the single-point correction time period in the initial value point set includes: obtaining a preset single-point correction time period; using the initial value point close to the single-point correction time period in the initial value point set as the initial solution, and using the Newton iteration method to iteratively solve the equation when the first derivative function is 0 until the iteration stop condition is satisfied, and outputting the exact solution.

[0063] In one embodiment, performing single-point correction using the optimal gyro correction point to obtain corrected navigation and positioning data includes: obtaining the real-time data of the celestial gyroscope at the optimal gyro correction point, performing data validity judgment on the real-time data according to a preset data validity criterion, if the real-time data is valid, then performing celestial gyro drift estimation on the real-time data and compensating for the positioning error caused, so as to obtain the output corrected navigation and positioning data.

[0064] In one embodiment, it further includes: performing data validity judgment on the real-time data according to a preset data validity criterion, if the real-time data is invalid, then using satellite data for position reset.

[0065] In one embodiment, the validity criteria include condition number judgment, latitude and longitude consistency check, and outlier detection.

[0066] In one embodiment, the gyro drift estimation model is: ; Where, is the vertical gyro drift, is the change in latitude, is the latitude, is the angular velocity of the Earth's rotation, is the time, is the change in longitude, is the longitude, is the Schuler frequency of the inertial navigation system.

[0067] For the specific limitations of the satellite signal source optimal point correction positioning device, reference can be made to the limitations of the satellite signal source optimal point correction positioning method in the above text, which will not be elaborated here. Each module in the above satellite signal source optimal point correction positioning device can be implemented in whole or in part by software, hardware, and their combinations. The above modules can be embedded in the processor of the computer device in hardware form or be independent of it, or be stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to the above modules.

[0068] In one embodiment, a computer device is provided. The computer device can be a terminal, and its internal structure diagram can be as Figure 9 shown. The computer device includes a processor, a memory, a network interface, a display screen, and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, it realizes a satellite signal source optimal point correction positioning method. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer covering the display screen, or a button, a trackball, or a touchpad set on the housing of the computer device, or an external keyboard, a touchpad, or a mouse, etc.

[0069] Those skilled in the art can understand, Figure 9The structure shown is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device to which the solution of this application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0070] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the method in the above embodiment are implemented.

[0071] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method in the above embodiment are implemented.

[0072] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the various embodiments provided in this application can include non-volatile and / or volatile memories. Non-volatile memories can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memories can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0073] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0074] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the appended claims.

Claims

1. A satellite signal source optimal point correction positioning method, characterized in that: The method comprises: Obtaining a gyro drift estimation model of the azimuth gyroscope, and constructing an optimization model by maximizing the denominator of the gyro drift estimation model to minimize the gyro drift rounding error; Solving the optimization model according to the angular velocity of the earth's rotation and the Shura frequency of the inertial navigation system to obtain the maximum point of the function corresponding to the denominator; A set of initial value points is obtained according to the maximum value points within the first two earth cycles of the voyage, and the precise value of the initial value points in the set of initial value points close to the single-point correction time period is solved by Newton iteration method, and the precise maximum value point in the single-point correction time period is calculated according to the precise value and the period of the first-order derivative function of the denominator term, and the precise maximum value point is used as the optimal gyro correction point; The optimal gyro correction point is used to perform single-point correction to obtain corrected navigation positioning data.

2. The method according to claim 1, characterized in that The optimization model is solved according to the angular velocity of the earth's rotation and the Shura frequency of the inertial navigation system to obtain the maximum value points of the function corresponding to the denominator term, including: Calculating the first-order derivative function of the denominator term of the gyro drift estimation model with respect to time, and substituting the earth's rotation angular velocity and the Shura frequency of the inertial navigation system into the first-order derivative function; The maximum point of the function corresponding to the denominator term is calculated according to the first-order derivative function.

3. The method according to claim 1, characterized in that The method of using Newton iteration method to solve the precise value of the initial value point in the initial value point set close to the single point correction time period includes: Get the preset single-point calibration time period; The initial value point in the initial value point set close to the single-point correction time period is taken as the initial solution, and the equation when the first-order derivative function is 0 is iteratively solved using the Newton iteration method until an iteration stop condition is met, and an exact solution is output.

4. The method according to claim 1, characterized in that: The single-point correction is performed using the optimal gyro correction point to obtain corrected navigation positioning data including: The real-time data of the celestial gyro at the optimal gyro correction point is obtained, and the data validity of the real-time data is judged according to a preset data validity criterion. If the real-time data is valid, the celestial gyro drift is estimated for the real-time data and the positioning error caused by compensation is compensated to obtain the navigation positioning data after output correction processing.

5. The method according to claim 4, characterized in that The method further comprises: The real-time data is judged for data validity according to a preset data validity criterion. If the real-time data is invalid, the position is reset using satellite data.

6. The method according to claim 4, characterized in that The validity criteria include condition number judgment, longitude and latitude consistency check and outlier detection.

7. The method according to claim 1, characterized in that The gyro drift estimation model is: in, Drifting towards the gyroscope for the sky, is the change in latitude, is the latitude, is the Earth's rotation angular velocity, For the moment, is the change in longitude, is the longitude, is the Shura frequency of the inertial navigation system.

8. A satellite signal source optimal point correction positioning device, characterized in that: The device comprises: An optimization model building module is used to obtain a gyro drift estimation model of the celestial gyroscope, and to build an optimization model by maximizing the denominator of the gyro drift estimation model to minimize the gyro drift rounding error; An optimization model solving module is used to solve the optimization model according to the angular velocity of the earth's rotation and the Shura frequency of the inertial navigation system to obtain the maximum value point of the function corresponding to the denominator; A correction point optimization module is used to obtain an initial value point set according to the maximum value points within the first two earth cycles of the voyage, use Newton iteration method to solve the precise value of the initial value point close to the single-point correction time period in the initial value point set, calculate the precise maximum value point within the single-point correction time period according to the precise value and the period of the first-order derivative function of the denominator term, and use the precise maximum value point as the optimal gyro correction point; The positioning correction module is used to perform single-point correction using the optimal gyro correction point to obtain corrected navigation positioning data.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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